Posts Tagged ‘ultrasound imaging’

Ultrasound in Radiology – Results of a European Survey

Reporter and Curator; Dror Nir, PhD

Ultrasound is by far, the most frequently used imaging modality in patient’s pathway being used by office-based clinicians and in most of hospitals’ departments. This is also true for cancer patients. As the contribution of imaging to the clinical assessment of patients becomes more substantial, the argument around “who is qualified” to perform such assessment is becoming louder and definitely more relevant!

Both the European and the North America Radiology societies are pushing towards establishment of centralized ultrasound services within the hospitals radiology department, still most ultrasound machines are spread between the different departments and being used by all practitioners. ESR’s working group on ultrasound published a report on the status of ultrasound-practice in European hospitals. Quite a shame; only 13% of the hospital addressed for participation in the survey reacted positively. I would like to highlight the most relevant conclusion from this survey, which is valid no matter which hand is holding the probe: Technique-oriented teaching, time and examinations are necessary to learn how to use Ultrasound properly within the framework of organ-oriented and disease training. Personally, I would support the idea that when it comes to management of cancer patients, this will become a “quality requirement” by law, similar to rules applicable to using radio-active substances.

 Here below is the full report:

Organisation and practice of radiological ultrasound in Europe: a survey by the ESR Working Group on Ultrasound

European Society of Radiology (ESR) 

Neutorgasse 9/2, AT-1010 Vienna, Austria

European Society of Radiology (ESR)

Email: communications@myesr.org

URL: http://www.myESR.org

Received: 25 April 2013Accepted: 26 April 2013Published online: 29 May 2013



To gather information from radiological departments in Europe assessing the organisation and practice of radiological ultrasound and the diagnostic practice and training in ultrasound.


A survey containing 38 questions and divided into four groups was developed and made available online. The questionnaire was sent to over 1,000 heads of radiology departments in Europe.


Of the 1,038 radiologists asked to participate in this survey, 123 responded. Excluding the 125 invitations to the survey that could not be delivered, the response rate was 13 %.


Although there was a low response rate, the results of this survey show that ultrasound still plays a major role in radiology departments in Europe: most departments have the technical capabilities to provide patients with up-to-date ultrasound examinations. Although having a centralised ultrasound laboratory seems to be the way forward, most ultrasound machines are spread between different departments. Ninety-one per cent of answers came from teaching hospitals reporting that training is regarded as an art and is needed in order to learn the basics of scanning techniques, after which working in an organ-oriented manner is the best way to learn how to integrate diagnostic US within the clinical context and with all other imaging techniques.

Main Messages

• Hospitals should introduce centralised ultrasound laboratories to allow for different competencies in US under the same roof, share human and technological resources and reduce the amount of equipment needed within the hospital.

• Technique-oriented teaching, time and examinations are necessary to learn how to use US properly within the framework of organ-oriented training.

• A time period of about 6 months dedicated solely to learning US scanning techniques is deemed sufficient in most cases.


The Working Group on ultrasound (US) of the European Society of Radiology was founded in 2009 with the aim of supporting increased quality and visibility of US within radiological departments as well as strengthening the position of US within the radiology community.

Among the many practical goals assigned to the group, one of the most important has been to gather information about the organisation and practice of radiological US in Europe.

This article reports the results of a survey assessing how diagnostic US is practiced and how training in US is organised in radiological departments of European hospitals. Questions were also aimed at evaluating the practice of US within both radiology and other hospital departments in order to understand the relationships among the different users of this technique. A comparison with the results of a previous survey on the US activities within 17 academic radiological departments throughout Europe published in 1999 by Schnyder et al. [1] was also attempted.


A questionnaire was developed to obtain data about the practice of diagnostic US within radiology departments in Europe.

The survey contained 38 questions that were divided into four groups:


Related to the hospital: location; dimensions; presence or absence of teaching duties.


Related to the workload of US: number of US examinations/year, amount of US equipment available; state of available technology; types of most frequent examinations; organisation of the US laboratory; presence of sonographers; methods of reporting and archiving US examinations.


Related to the teaching of US to radiology residents: organisation and duration of training programmes; number of examinations to be performed before completion of the training period; presence of training programmes dedicated to sonographers or other non-radiology residents.


Related to the US examinations performed outside radiology in each hospital; clinical specialists most often involved in performing directly US; availability of special techniques, such as contrast-enhanced ultrasound (CEUS); methods of reporting and archiving US examinations.

The questionnaire was made available online and an invitation to fill it in was sent to all 1,038 heads of radiology departments throughout Europe within the database of the European Society of Radiology. The invitation was repeated three times over a period of 3 months, between June and August 2011.


There were 123 responses to the questionnaire. Considering that 125/1,038 e-mail messages were reported as “undelivered”, the response rate to the invitation was 13 %. Many responders did not answer all the questions presented in the questionnaire, and some answers and comments were somewhat difficult to understand and evaluate.

First group of questions

Answers were gathered from different parts of Europe; 63.4 % were from five nations (Germany, Austria, France, Spain and Italy). The distribution according to countries is presented in Table 1.

Table 1

Nationality of responders

Germany (DE)


Austria (AT)


France (FR)


Spain (ES)


Italy (IT)


Hungary (HU)


Switzerland (CH)


The Netherlands (NL)


Turkey (TR)




Czech Rep (CZ)


Poland (PL)


Denmark (DK)


Romania (RO)


Norway (NO)


Croatia (HR)


Portugal (PT)


Belgium (BE)


Greece (GR)


Montenegro (ME)


Lithuania (LT)


Ireland (IE)


Serbia (RS)


Sweden (SE)


There were 25 responses (20.3 %) from hospitals with fewer than 400 beds, 52 (42.3 %) from hospitals with between 400 and 1,000 beds and 46 (37.4 %) from hospitals with more than 1,000 beds. Most answers were from teaching hospitals (91.1 %).

Second group of questions

Most radiology departments (77 %) have fewer than 10 working US units; 22 % have between 10 and 20 US machines; only 0.8 % have more than 20 machines. Small, portable units are available in 64.5 % of departments, 3D/4D capabilities are present in 52 % and elastography in 48.2 %, and 67.3 % have the possibility to perform CEUS examinations.

Up to 57.6 % of radiology departments perform more than 10,000 examinations per year; between 3,000 and 10,000 examinations per year are performed in 33.1 % of cases; only 9.3 % of departments perform fewer than 3,000 examinations.

Abdominal US is the most frequent exam (51.51 %), followed by breast (14.46 %), musculoskeletal (11.59 %), pelvic (10.88 %) and vascular (10.42 %) US examinations. Contrast-enhanced US (CEUS) studies constitute about 4.39 %. US is used by radiologists in emergency in 96.6 % of cases and in paediatrics in 74.6 %. Comments indicate that most of those who answered “no” did not have a paediatric section in their hospital.

Transvaginal US is used in obstetric examinations by 15.8 % of responders and in gynaecological studies by 50.7 %. Endoscopic US is used by radiologists in 13.4 % and intravascular US in 14.6 %; radiologists are called by surgeons for intraoperative US in 64.2 % of cases.

There were 49 responders who indicated the actual number of US examinations performed/year. The characteristics of hospitals in which the radiology department performs more than 20,000 ultrasound examinations/year are presented in Table 2.

Table 2

Characteristics of the hospitals in which the radiology department performs more than 20,000 US examinations/year (nationality, presence/absence of teaching duties, number of inpatients, number of US machines available, ratio between number of US examinations performed by non-radiology specialists vs. radiologists)


Those who reported fewer than 5,000 US examinations/year are reported in Table 3.

Table 3

Characteristics of the hospitals in which the radiology department performs less than 5,000 US examinations/year (nationality, presence/absence of teaching duties, number of inpatients, number of US machines available, ratio between number of US examinations performed by non-radiology specialists vs. radiologists)


Third group of questions

The first question in this group was whether the hospital was organised with a centralised US laboratory where physicians from all specialties work together.

There were 13/110 positive answers (11.8 %) from Germany (5), Spain (3), Austria (2), Hungary (2) and Croatia (1). All other hospitals have US machines scattered throughout the different radiological and non-radiological departments. The centralised US laboratory is organised together by the radiology and the internal medicine departments in three cases; it is truly multidisciplinary, with all specialties concurring, in three others; it is run by radiology in two. The remaining two positive answers did not provide further detail about their organisation.

The second question related to the role of sonographers. Only 15/110 (13.6 %) department heads stated they work with sonographers. They are located in Spain (3), Germany (2), UK (2), The Netherlands (2), Austria (1), Belgium (1), Ireland (1), Lithuania (1) and Montenegro (1). In all others, US examinations are done directly by the radiologists. There were 12 comments describing how the work of sonographers is organised. Sonographers do both the examination and the report, with the radiologist checking difficult cases only in four hospitals; sonographers do the studies and the radiologist takes a final look and writes the reports in six; two departments state they use sonographers for vascular examinations only.

The third question related to the organisation of training programmes in US. Radiology residents are trained in 91.1 % of responders. Some centres organise a theoretical course on basic principles of US before starting practical activity. Then, clinical practice is usually performed according to organ/systems training schemes. Residents work under close supervision of a senior radiologist: they approach the patient, perform a preliminary examination and issue a first report, which is then checked by the expert. The aim is to obtain progressive growth of competences: from scanning capabilities, to reporting capabilities, to complete independence.

The length of the period of training within the US laboratory in the various teaching hospitals and the minimum number of US examinations required before the end of the residency period are summarised in Tables 4 and5.

Table 4

Length of the period of training within the US laboratory in the 84 teaching hospitals that reported it

No. of teaching hospitals

Length of training


<4 months


4–6 months


6–12 months


>1 year

Table 5

Minimum number of US examinations to be performed before the end of the residency period in the 75 teaching hospitals that reported it

No. of teaching hospitals

Minimum no. of US examination









There was a direct correlation between the number of US exams performed in the department and the depth of US involvement during training: training programmes in the two hospitals where the lowest number of US examinations/year is performed indicate a period of 3 months and 250 and 500 examinations. However, a hospital with a workload of 45,000 US studies per year (in which, however, the examinations are performed by sonographers) suggested only 2–3 months of training and 100 exams before the end of the residency period.

Training is also provided for non-radiology residents in 37 hospitals. It is most frequently offered to internal medicine, gastroenterology, surgery, anesthesiology, vascular surgery and paediatrics. Comments indicate that these radiology courses allow only theoretical teaching, since observation, but not direct contact with patient, is provided for non-radiologists.

All 15 departments working with sonographers provide, or are planning to provide, starting in 2012, training courses for these professionals. These include both theory and practice; the theoretical part is done, in some cases, together with radiology residents.

As an important technical point, it must be noted that US images performed by radiologists are recorded into PACS systems in 85.6 % of cases. Comments on this question indicated that not all equipment is linked to PACS and that only selected images or videos are often archived; furthermore, technical problems in archiving videos have been reported.

A final group of questions pertained to the US examinations performed outside the radiology department in each hospital.

One question asked about the proportion of US examinations performed by radiologists vs. those performed by non-radiologists. European radiologists, as a whole, still perform a higher number of examinations (61.27 %) than non-radiologists (38.32 %). Differences in the percentage of studies performed in the different hospitals are presented in Table 6.

Table 6

Proportion of US examinations performed by radiologists vs. non-radiologists. Although radiologists, as a whole, perform more US examinations than non-radiologists, the table shows there are differences among different departments, with slightly more than 50 % performing more than 70 % of the studies

% of hospital US exams performed by radiologists

No. of radiology departments

≥90 %

25 (20.32 %)

70–90 %

37 (30.08 %)

10–70 %

57 (46.35 %)

<10 %

4 (3.25 %)

Comments indicate that most OB/GYN, neurology, vascular, urology, internal medicine, anaesthesiology and gastroenterology departments run their own US units in their wards. CEUS is used in 35.1 % of gastroenterology departments, in 15.1 % of internal medicine, in 10.6 % of transplant units and in 10.4 % of nephrology departments.

The examinations performed out of the radiology department are formally reported in 64.4 % of cases only. Comments indicate that reports are fully stored within the Hospital Information System (HIS) in 31 cases; storage is only partial in 24; no HIS storage is used in 5 cases.

US images obtained outside of the radiology department are recorded into the PACS system of the hospital in 18.3 % of cases only.


Several considerations are raised from the results of this survey.

First, there was a low response rate to the survey itself. There were only 123 answers to the 913 received messages asking for information from radiology department heads (a mere 13 %). It is hoped that this low response rate relates to the many committments on their side and not to low interest in the role of US within radiology [23].

Second, most responders indicated that US is still an important part of the activities of the radiology department. Only 9.3 % report fewer than 3,000 examinations/year. It must be noted that there may be a bias in these figures, since it is conceivable that responders were more interested in US than those who did not answer the questionnaire (even if there were responders who indicated that, in their hospital, US is done mostly outside of the radiology department). Most of the workload is due to abdomino-pelvic exams, followed by breast, musculoskeletal and vascular applications. Furthermore, state-of-the-art equipment is used in about 50 % and CEUS can be performed in 64.2 %. Portable machines are available in 64.5 %, transvaginal US examinations of the pelvis are used in 50.7 %, and radiologists are still involved in intraoperative US examinations in 64.2 % of cases. Most departments still have the technical capabilities to provide up-to-date US answers to the requests they receive.

Another consideration relates to the organisation of US within the hospital. In most cases US machines are scattered throughout the different departments, and only 13 hospitals have organised a centralised US laboratory where all physicians from different specialities come to examine their patients. Although centralisation seems the best way to run a US service, there are several factors that can explain why this is not the case, many of which stem from tradition. US laboratories, in fact, commonly arose separately from one another, following the initiatives of the different specialists who started introducing this technique in their practice. Then, there is a disposition to maintain independence and separate departmental income from the activities as well as the desire to control all aspects of patients’ care.

Only 15 departments reported they are working with sonographers. Although it is known that in Europe most radiologists perform US examinations directly, it is believed that this figure underestimates the real contribution of these professionals. A possible explanation is that only three hospitals from the UK answered the questionnaire; in the UK sonographers play a major role in dealing with the US workload.

Most answers to the questionnaire came from teaching hospitals (91.1 %). Comments on how training is organised state that US scanning is commonly regarded as an art, taught from maestro to pupil, with progressive growth in scanning and reporting capabilities. In addition, most report that US is taught within an organ-/system-oriented training system. The “art” of US is highly dependent on the operator’s dedication and technical ability, and this has to be properly taught. Additionally, a period of training within a dedicated US laboratory is probably needed to learn the basics of scanning techniques. After learning the technique, working in an organ-oriented manner is surely the best way to learn how to integrate diagnostic US within the clinical context and with all other imaging techniques.

There were 13 teaching hospitals in which fewer than 4 months is deemed sufficient, and in 20 cases having fewer than 500 examinations before the end of the residency is regarded as complete training.

The low number of US examinations performed in some training centres can jeopardise teaching. The recruitment of patients for adequate training can be impossibile to obtain in low-volume practices, leading to a further decrease of radiological US for future generations of radiologists. Furthermore, the use of sonographers can make teaching the practical skills of US scanning difficult. In a hospital with high-volume US practice (45,000 cases/year) in which the examinations are performed by sonographers, residents are asked to remain in the US laboratory only for 2–3 months and to perform only 100 examinations before the end of training. When in clinical practice in a hospital without sonographers, these radiologists would not be able to carry out even routine diagnostic US examinations. On the contrary, the role of expert sonographers as a resource to provide practical training to radiology residents has not been considered and can be explored.

The results of this survey show a large heterogeneity in the use of US within radiology throughout Europe. There are hospitals in which the majority of US examinations are still performed by radiologists, and others in which radiologists are left with only a small proportions of studies.

Similar findings were observed by Schnyder et al. in 1999 [1]. From their survey in 17 academic radiology departments throughout Europe, these authors reported that in some nations radiologists had full control of US, while this was not the case in Germany, Austria and Switzerland. The situation seems somewhat worse today, since there are 22 hospitals (18.2 %) in different nations (Austria, Poland, Germany, France, UK, Norway, Switzerland and Italy) in which radiologists perform less than 70 % of all US examinations and 5 (4 %) who answered they do less than 10 % of the studies. Since the answers to the questionnaire were provided by radiology departments, the figures for radiological activity can be considered as precise. On the contrary, it is possible that those answers on the US activities out of radiology can be regarded as an estimate. However, to the best of our knowledge, the data in the survey of Schnyder et al. were also obtained in a similar way, and a comparison can thus be made.

The percent decrease in the number of US examinations done in radiology vs. those performed outside radiology is probably related to a marked increase of the use of US by non-radiology clinicians rather than to a decreased attention to this technique by radiologists. In fact, new specialists, such as emergency physicians and anesthesiologists, are now using this technique as a complement to their visit or as a guide to therapeutic manoeuvres, and the so-called “point-of-care US” philosophy, in which US equipment accompanies the physician at the patient’s bedside to guide his/her therapeutic decision making, is gaining popularity.

An additional point to be considered relates to the recording of US reports and images into the hospital informations system and PACS. US examinations performed by radiologists are archived within the PACS system in 85.6 %, while those performed by non-radiologists are stored in only 18.3 % of cases. Furthermore, radiologists provide a formal report in virtually all cases, while examinations performed out of radiology are formally reported in 64.4 %. Costs and technical difficulties in connecting all equipment to PACS and RIS are described as reasons for not recording US images, and this is especially the case for recording of video clips. The use of “point-of-care US” is a further difficulty for connecting equipment to PACS, and, within this framework, the US exam is not regarded as a separate study but as part of the physician visit. However, to have all US images and reports of the patient recorded and available for consultation could greatly help during subsequent studies, and efforts have to be made to develop consensus with clinical colleagues to increase connectivity and to report all US studies, at least as a description within the patients’ charts. Within the framework of the relationships established by the ESR WG in US with the European Federation of Societies for Ultrasound in Medicine and Biology (EFSUMB), it has been agreed to prepare and publish a recommendation about the necessity, for all US examinations, of a formal report and proper archiving of both report and images.


Two points of action can be suggested.

The first relates to the centralisation of the US laboratory. Although at the moment only a small number of hospitals are working according to this model, radiologists should take the lead in proposing such organisation [4]. This would allow the gathering of all the different competencies in US under the same roof, to share human and technological resources and to reduce the amount of equipment needed within the hospital. In an era of cost containments, a centralised US laboratory can allow each US scanner operate for longer hours and with higher numbers of examinations, resulting in an optimisation of resources. Furthermore, requests to upgrade and/or renovate equipment would possibly be easier if coming from a large laboratory and shared by different hospital departments. Another advantage would be having people with different backgrounds work in the same environment, thus promoting exchange and integration of their knowledge and possibly resulting in better patient care. It would be easier, in this respect, to prepare institutional guidelines and protocols that place US in the correct perspective towards all other imaging modalities and, most importantly, towards patients’ needs. It is not clear from the survey how this way of working is organised on a day-to-day basis, and especially how emergency services are provided (i.e. if all specialists concur in the emergency or if this is left to radiologists only), but an integrated management and organisational infrastructure bears numerous advantages for cost containment, quality standards and efficiency.

The second point of action relates to training in US within radiology residency programmes. In the opinion of the ESR Working Group on US, radiologists need to develop consensus on how many examinations under tutorship residents have to perform and on how much time they have to spend in ultrasound before the end of the training period. The results of the survey vary widely. However, out of 75 training centres that reported on the number of examinations, there were 39 (52 %) providing figures between 1,000 and 2,000 or higher. Therefore, approximately 2,000 seems to be a figure on which consensus can be reached. This figure also complies with what is suggested by the EFSUMB [5]. This federation provides recommendations about the number of examinations for training in the different subspeciality areas of US: the sum of studies for abdomen, breast, musculoskeletal and vascular training is 1,500, while figures for head and neck are not provided. The length of training is more complex to decide. A distinction has to be made here between the time needed to learn the technique of US scanning and the time needed to learn how to use US properly, to integrate it with other imaging techniques and to provide useful reports. In order to perform US, both approaches are needed. Technique-oriented teaching is necessary to learn how to perform the studies and to identify anatomy and pathology. Time and exams are needed to learn how to use US properly within the framework of organ-oriented training. A period of time of about 6 months dedicated solely to learning the US scanning technique can possibly be considered sufficient, as suggested by 76.2 % of responders. The capabilities of residents to perform US examinations have to be assessed during the training period, especially during and at the end of the technique-oriented part. It is known that the learning curve can vary widely among trainees, and longer times and higher numbers of examinations may be needed in some cases [6]. Additional time should be spent, and exams taken, during organ-oriented training. It must be underlined that organ-oriented teaching needs to include the proper role of US in each subspeciality and also take into account technical advances such as CEUS, 3D/4D and elastography and to use them when needed.


This article was kindly prepared by the ESR Working Group on US (M. Bachmann-Nielsen, M. Claudon, L. E. Derchi, S. Elliott, G. Mostbeck, C. Nicolau, S. Yarmenitis, A. Zubarev, Y. Menu–Chair of the ESR Professional Organisation Committee and J.A. Reekers–Chair of the ESR Subspecialty Societies Committee) on behalf of the European Society of Radiology. It was approved by the ESR Executive Council in April 2013.

Open Access This article is distributed under the terms of the Creative Commons Attribution License which permits any use, distribution, and reproduction in any medium, provided the original author(s) and the source are credited.



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Ultrasound imaging as an instrument for measuring tissue elasticity: “Shear-wave Elastography” VS. “Strain-Imaging”

Writer and curator: Dror Nir, PhD

In the context of cancer-management, imaging is pivotal. For decades, ultrasound is used by clinicians to support every step in cancer pathways. Its popularity within clinicians is steadily increasing despite the perception of it being less accurate and less informative than CT and MRI. This is not only because ultrasound is easily accessible and relatively low cost, but also because advances in ultrasound technology, mainly the conversion into PC-based modalities allows better, more reproducible, imaging and more importantly; clinically-effective image interpretation.

The idea to rely on ultrasound’s physics in order to measure the stiffness of tissue lesions is not new. The motivation for such measurement has to do with the fact that many times malignant lesions are stiffer than non-malignant lesions.

The article I bring below; http://digital.studio-web.be/digitalMagazine?issue_id=254 by Dr. Georg Salomon and his colleagues, is written for lay-readers. I found it on one of the many portals that are bringing quasi-professional and usually industry-sponsored information on health issues; http://www.dieurope.com/ – The European Portal for Diagnostic Imaging. Note, that when it comes to using ultrasound as a diagnostic aid in urology, Dr. Georg Salomon is known to be one of the early adopters for new technologies and an established opinion leader who published many peer-review, frequently quoted, papers on Elastography.

The important take-away I would like to highlight for the reader: Quantified measure of tissue’s elasticity (doesn’t matter if is done by ShearWave or another “Elastography” measure implementation) is information that has real clinical value for the urologists who needs to decide on the right pathway for his patient!

Note: the highlights in the article below are added by me for the benefit of the reader.

Improvement in the visualization of prostate cancer through the use of ShearWave Elastography


Dr Georg Salomon1 Dr Lars Budaeus1, Dr L Durner2 & Dr K Boe1

1. Martini-Clinic — Prostate Cancer Center University Hospital Hamburg Eppendorf Martinistrasse 52, 20253 Hamburg, Germany

2. Urologische Kilnik Dr. Castringius Munchen-Planegg Germeringer Str. 32, 82152 Planegg, Germany

Corresponding author; PD Dr. Georg Salomon

Associate Professor of Urology

Martini Clinic

Tel: 0049 40 7410 51300



Prostate cancer is the most common cancer in males with more than 910,000 annual cases worldwide. With early detection, excellent cure rates can be achieved. Today, prostate cancer is diagnosed by a randomized transrectal ultrasound guided biopsy. However, such randomized “blind” biopsies can miss cancer because of the inability of conventional TRUS to visualize small cancerous spots in most cases.

Elastography has been shown to improve visualization of prostate cancer.

The innovative ShearWave Elastography technique is an automated, user-friendly and quantifiable method for the determination of prostatic tissue stiffness.

The detection of prostate cancer (PCA) has become easier thanks to Prostate Specific Anti­gen (PSA) testing; the diagnosis of PCA has been shifted towards an earlier stage of the disease.

Prostate cancer is, in more than 80 % of the cases, a heterogeneous and multifocal tumor. Conventional ultra­sound has limitations to accurately define tumor foci within the prostate. This is due to the fact that most PCA foci are isoechogenic, so in these cases there is no dif­ferentiation of benign and malignant tissue. Because of this, a randomized biopsy is performed under ultrasound guidance with at least 10 to 12 biopsy cores, which should represent all areas of the prostate. Tumors, however, can be missed by this biopsy regimen since it is not a lesion-targeted biopsy. When PSA is rising — which usually occurs in most men — the originally negative biopsy has to be repeated.

What urologists expect from imag­ing and biopsy procedures is the detection of prostate cancer at an early stage and an accurate description of all foci within the prostate with different (Gleason) grades of differentiation for best treatment options.

In the past 10 years a couple of new innovative ultrasound techniques (computerized, contrast enhanced and real time elastography) have been introduced to the market and their impact on the detection of early prostate cancer has been evaluated. The major benefit of elastography compared to the other techniques is its ability to provide visualization of sus­picious areas and to guide the biopsy needle, in real time, to the suspicious and potentially malignant area.

Ultrasound-based elastography has been investigated over the years and has had a lot of success for increasing the detection rate of prostate cancer or reducing the number of biopsy sam­ples required. [1-3]. Different compa­nies have used different approaches to the ultrasound elastography technique (strain elastography vs. shear wave elastography). Medical centers have seen an evolution in better image qual­ity with more stable and reproducible results from these techniques.

One drawback of real time strain elastography is that there is a sig­nificant learning curve to be climbed before reproducible elastograms can be generated. The technique has to be performed by compressing and then decompressing the ultrasound probe to derive a measurement of tissue displacement.

Today there are ultrasound scanners on the market, which have the ability to produce elastograms without this “manual” assistance: this technique is called shear-wave elastography. While the ultrasound probe is being inserted transrectally, the “elastograms” are generated automatically by the calcu­lation of shear wave velocity as the waves travel through the tissue being examined, thus providing measure­ments of tissue stiffness and not dis­placement measurements.

There are several different tech­niques for this type of elastography. The FibroScan system, which is not an ultrasound unit, uses shear waves (transient elastography) to evaluate the advancement of the stiffness of the liver. Another technique is Acous­tic Radiation Force Impulse or ARF1 technique, also used for the liver. These non-real-time techniques only provide a shear wave velocity estimation for a single region of interest and are not currently used in prostate imaging.

A shear wave technology that pro­vides specific quantification of tissue elasticity in real-time is ShearWave Elastography, developed by Super-Sonic Imagine. This technique mea­sures elasticity in kilopascals and can provide visual representation of tis­sue stiffness over the entire region of interest in a color-coded map on the ultrasound screen. On a split screen the investigator can see the conven­tional ultrasound B-mode image and the color-coded elastogram at the same time. This enables an anatomi­cal view of the prostate along with the elasticity image of the tissue to guide the biopsy needle.

In short, ShearWave Elastography (SWE) is a different elastography technique that can be used for several applications. It automatically gener­ates a real-time, reproducible, fully quantifiable color-coded image of tissue elasticity.

QUANTIFICATION OF TISSUE STIFFNESS Such quantification can help to increase the chance that a targeted biopsy is positive for cancer.

It has been shown that elastography-targeted biopsies have an up to 4.7 times higher chance to be positive for cancer than a randomized biopsy [4J. Shear-Wave Elastography can not only visual­ize the tissue stiffness in color but also quantify (in kPa) the stiffness in real time, for several organs including the prostate. Correas et al, reported that with tissue stiffness higher than 45 to 50 kPa the chance of prostate cancer is very high in patients undergoing a pros­tate biopsy. The data from Gorreas et al showed a sensitivity of 80 % and a high negative predictive value of up to 9096. Another group (Barr et A) achieved a negative predictive value of up to 99.6% with a sensitivity of 96.2% and specific­ity of 962%. With a cut-off of 4D kPa the positive biopsy rate for the ShearWave Elastography targeted biopsy was 50%, whereas for randomized biopsy it was 20.8 95. In total 53 men were enrolled in this study.

Our group used SWE prior to radical prostatectomy to determine if the Shear-Wave Elastography threshold had a high accuracy using a cutoff >55 kPa. (Fig 1)

We then compared the ShearWave results with the final histopathological results. [Figure I], Our results showed the accuracy was around 78 % for all tumor foci We were also able to verify that ShearWave Elastography targeted biopsies were more likely to be posi­tive compared to randomized biopsies. [Figures 2, 3]




SWE is a non-invasive method to visualize prostate cancer foci with high accuracy, in a user-friendly way. As Steven Kaplan puts it in an edi­torial comment in the Journal of Urology 2013: “Obviously, large-scale studies with multicenter corroboration need to be performed. Nevertheless, SWE is a potentially promising modality to increase our efficiency in evaluating prostate diseases:’



  1. Pallweln, L. et al-. Sonoelastography of the prostate: comparison with systematic biopsy findings in 492 patients. European journal of radiology, 2008. 65(2): p. 304-10.
  2. Pallwein, L., et al., Comparison of sono-elastography guided biopsy with systematic biopsy: Impact on prostate cancer detecton. European radiology, 2007_ 17.(9) p. 2278-85.
  3. Salomon, G., et al., Evaluation of prostate can cer detection with ultrasound real-time elas-tographyl a companion with step section path­ological analysis after radical prostatectomy. European urology, 2008. 5446): p. 135462-
  4. Aigner, F., at al., Value of real-time elastography targeted biopsy for prostate cancer detection in men with prostate specific antigen 125 ng/mi or greater and 4-00 ng/ml or Lass. The Journal of urology, 2010. 184{3): p. 813.7,

Other research papers related to the management of Prostate cancer and Elastography were published on this Scientific Web site:

Imaging: seeing or imagining? (Part 1)

Early Detection of Prostate Cancer: American Urological Association (AUA) Guideline

Today’s fundamental challenge in Prostate cancer screening

State of the art in oncologic imaging of Prostate.

From AUA2013: “HistoScanning”- aided template biopsies for patients with previous negative TRUS biopsies 

On the road to improve prostate biopsy

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Ultrasound-based Screening for Ovarian Cancer

Author: Dror Nir, PhD

Occasionally, I check for news on ovarian cancer screening. I do that for sentimental reasons; I started the HistoScanning project aiming to develop an effective ultrasound-based screening solution for this cancer.

As awareness for ovarian cancer is highest in the USA, I checked for the latest news on the NCI web-site. I found that to-date: “There is no standard or routine screening test for ovarian cancer. Screening for ovarian cancer has not been proven to decrease the death rate from the disease.

Screening for ovarian cancer is under study and there are screening clinical trials taking place in many parts of the country. Information about ongoing clinical trials is available from the NCI Web site.”

I also found that:

Estimated new cases and deaths from ovarian cancer in the United States in 2013:

  • New cases: 22,240
  • Deaths: 14,030

To get an idea on the significance of these numbers, lets compare them to the numbers related to breast cancer:

Estimated new cases and deaths from breast cancer in the United States in 2013:

  • New cases: 232,340 (female); 2,240 (male)
  • Deaths: 39,620 (female); 410 (male)

Death rate of ovarian cancer patients is almost 4 times higher than the rate in breast cancer patients!

Therefore, I decided to raise awareness to the results achieved for ovarian HistoScanning in a double-blind multicenter European study that was published in European Radiology three years ago. The gynecologists who recruited patients to this study used standard ultrasound machines of GE-Medical. I would like as well to disclose that I am one of the authors of this paper:

A new computer-aided diagnostic tool for non-invasive characterisation of malignant ovarian masses: results of a multicentre validation study, Olivier Lucidarme et.al., European Radiology, August 2010, Volume 20, Issue 8, pp 1822-1830



To prospectively assess an innovative computer-aided diagnostic technology that quantifies characteristic features of backscattered ultrasound and theoretically allows transvaginal sonography (TVS) to discriminate benign from malignant adnexal masses.


Women (n = 264) scheduled for surgical removal of at least one ovary in five centres were included. Preoperative three-dimensional (3D)-TVS was performed and the voxel data were analysed by the new technology. The findings at 3D-TVS, serum CA125 levels and the TVS-based diagnosis were compared with histology. Cancer was deemed present when invasive or borderline cancerous processes were observed histologically.


Among 375 removed ovaries, 141 cancers (83 adenocarcinomas, 24 borderline, 16 cases of carcinomatosis, nine of metastases and nine others) and 234 non-cancerous ovaries (107 normal, 127 benign tumours) were histologically diagnosed. The new computer-aided technology correctly identified 138/141 malignant lesions and 206/234 non-malignant tissues (98% sensitivity, 88% specificity). There were no false-negative results among the 47 FIGO stage I/II ovarian lesions. Standard TVS and CA125 had sensitivities/specificities of 94%/66% and 89%/75%, respectively. Combining standard TVS and the new technology in parallel significantly improved TVS specificity from 66% to 92% (p < 0.0001).

table 3

table 4

An example of an ovary considered to be normal with TVS.

An example of an ovary considered to be normal with TVS.

The same TVS false-negative ovary with OVHS-detected foci of malignancy. The presence of an adenocarcinoma was confirmed histologically.

The same TVS
false-negative ovary with OVHS-detected foci of malignancy. The presence of an
adenocarcinoma was confirmed histologically.


Computer-aided quantification of backscattered ultrasound is  highly sensitive for the diagnosis of malignant ovarian masses.

 Personal note:

Based on this study a promising offer for ultrasound-based screening method for ovarian cancer was published in:  Int J Gynecol Cancer. 2011 Jan;21(1):35-43. doi: 10.1097/IGC.0b013e3182000528.: Mathematical models to discriminate between benign and malignant adnexal masses: potential diagnostic improvement using ovarian HistoScanning. Vaes EManchanda RNir RNir DBleiberg HAutier PMenon URobert A.

Regrettably, the results of these studies were never transformed into routine clinical products due to financial reasons.

Other research papers related to the management of Prostate cancer were published on this Scientific Web site:

Beta-Blockers help in better survival in ovarian cancer

Ovarian Cancer and fluorescence-guided surgery: A report

Role of Primary Cilia in Ovarian Cancer

Squeezing Ovarian Cancer Cells to Predict Metastatic Potential: Cell Stiffness as Possible Biomarker

BRCA1 a tumour suppressor in breast and ovarian cancer – functions in transcription, ubiquitination and DNA repair

Warning signs may lead to better early detection of ovarian cancer


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Author – Writer: Dror Nir, PhD

To those of you who did not know, 2013 is the year of the ultrasound: http://www.ultrasound2013.org/. This initiative was launched by AIUM and its objectives:

  • Raise awareness of the value and benefits of ultrasound among patients, health care providers, and insurers
  • Provide ultrasound education and evidence-based guidelines for health care providers
  • Educate insurers about the cost savings and patient benefits associated with performing an ultrasound study when scientific evidence supports its potential effectiveness compared to other imaging modalities
  • Educate patients about the benefits of ultrasound as the appropriate imaging modality for their care
  • Encourage the incorporation of ultrasound into medical education

 Quoting from the ultrasound first web-site:

The initiative is designed to call attention to the safe, effective, and affordable advantages of ultrasound as an alternative to other imaging modalities that are more costly and/or emit radiation. For a growing number of clinical conditions, ultrasound has been shown to be equally effective in its diagnostic capability, with a distinct advantage in safety and cost over computed tomography and magnetic resonance imaging. Despite this advantage, evidence suggests that ultrasound is vastly underutilized. Ultrasound First focuses on educating health care workers, medical educators, insurers, and patients of the benefits of ultrasound in medical care. “There is growing support and public awareness for the need to reduce and carefully monitor patients’ exposure to radiation during medical imaging. The use of ultrasound as an alternative imaging modality will help achieve that goal while reducing cost,” states AIUM President Alfred Abuhamad, MD. “Many health care workers and insurers are unacquainted with the range of conditions for which ultrasound has been shown to have superior diagnostic capabilities. Disseminating this knowledge to health care workers and incorporating ultrasound in medical protocols where scientific evidence has shown its diagnostic efficacy will undoubtedly improve patient safety and reduce cost. The time to act is now.”

 A primary component of Ultrasound First is providing clinical evidence for the use of ultrasound. To that aim, the Journal of Ultrasound in Medicine has launched a special feature, the Sound Judgment Series, consisting of invited articles highlighting the clinical value of using ultrasound first in specific clinical diagnoses where ultrasound has shown comparative or superior value. Clinical conditions that will be addressed in the series include postmenopausal bleeding, right lower quadrant pain, pelvic pain, right upper quadrant pain, and shoulder pain, among others. This series will serve as an important educational resource for health care workers and educators.  On the clinical evidence page one can find reasoning for why ultrasound first. Not much related to cancer diagnosis and management. The only interesting claim is:Ultrasound-guided surgery: Its use to remove tumors from women who have palpable breast cancer is much more successful than standard surgery in excising all the cancerous tissue while sparing as much healthy tissue as possible.”

In support of this initiative The Journal of Ultrasound in Medicine has launched a special series, Sound Judgment, comprised of invited articles highlighting the clinical value of using ultrasound first in specific clinical diagnoses where ultrasound has shown comparative or superior value. So far it includes only two items related to management of cancer: Sonography of Facial Cutaneous Basal Cell Carcinoma, A First-line Imaging Technique; by Ximena Wortsman, MD, and Quantitative Assessment of Tumor Blood Flow Changes in a Murine Breast Cancer Model After Adriamycin Chemotherapy Using Contrast-Enhanced Destruction-Replenishment Sonography; by Jian-Wei Wang, MD et. al. The devoted readers of our Open Access Scientific Journal might find the article by Dr. Wortsman, MD bringing complementary information to a previous post of mine: Virtual Biopsy – is it possible?. Qouting from this article: “Cutaneous basal cell carcinoma is the most common cancer in human beings, and the face is its most frequent location. Basal cell carcinoma is rarely lethal but can generate a high degree of disfigurement. Of all imaging techniques, sonography has proven to support the diagnosis and provide detailed anatomic data on extension in all axes, the exact location, vascularity, and deeper involvement. This information can be used for improving management and the cosmetic results of patients.”

 The article gives clear presentation of the problem and includes demonstrative pictures:


Figure: Basal cell carcinoma with dermal involvement (transverse view, nasal tip). Grayscale sonography (A) and 3-dimensional reconstruction (B, 5- to 8-second sweep) show a 10.1-mm (wide) × 1.4-mm (deep) well-defined hypoechoic oval lesion (between markers in A and outlined in B) that affects the dermis (d) of the left nasal wing. Notice the hyperechoic spots (arrowheads) within the lesion. The nasal cartilage (c) is unremarkable; asterisk indicates basal cell carcinoma.

Basal cell carcinoma with dermal and subcutaneous involvement (transverse view, frontal region). A, Grayscale sonography shows a 11.4-mm (wide) × 6.6-mm (deep) well-defined oval hypoechoic lesion that involves the dermis (d) and subcutaneous tissue (st). There are hyperechoic spots (arrowheads) within the tumor. B, Color Doppler sonography shows increased vascularity within the tumor (asterisk). C, Three-dimensional sonographic reconstruction (5- to 8-second sweep) highlights the lesion (asterisk, outlined); b indicates bony margin of the skull.

Basal cell carcinoma with dermal and subcutaneous involvement (transverse view, frontal region). A, Grayscale sonography shows a 11.4-mm (wide) × 6.6-mm (deep) well-defined oval hypoechoic lesion that involves the dermis (d) and subcutaneous tissue (st). There are hyperechoic spots (arrowheads) within the tumor. B, Color Doppler sonography shows increased vascularity within the tumor (asterisk). C, Three-dimensional sonographic reconstruction (5- to 8-second sweep) highlights the lesion (asterisk, outlined); b indicates bony margin of the skull.


Figure: Pleomorphic presentations of basal cell carcinoma lesions on grayscale sonography (transverse views). Notice the variable shapes of the tumors.


Figure: Frequently, blood flow can be detected within the tumor and its periphery, with slow-flow arteries or veins. The latter vascular data can orient the clinician about the distribution and amount of blood flow that he or she will face during surgery. Despite the fact that basal cell carcinomas usually do not present high vascularity, it should be kept in mind that many of basal cell carcinoma operations are performed in the offices of clinicians and not in the main operating rooms of large hospitals. Nevertheless, the finding of high vascularity within a clinically diagnosed basal cell carcinoma may suggest another type of skin cancer that could occasionally mimic basal cell carcinoma, such as squamous cell carcinoma, Merkel cell carcinoma, or a metastatic tumor. The above figure presents variable degrees of vascularity in basal cell carcinoma lesions going from hypovascular to hypervascular on color and power Doppler sonography (transverse views)


Figure: The depth correlation between sonography (variable frequency) and histologic analysis in facial basal cell carcinoma has been reported to be excellent. Thus, the intraclass correlation coefficient for comparing thickness for the two methods (sonography and histologic analysis) that has been described in literature is 0.9 (intraclass correlation coefficient values ≥0.9 are very good; 0.70–0.89 are good; 0.50–0.69 are moderate; 0.30–049 are mediocre; and ≤0.29 are bad). Two rare sonographic artifacts have been described in basal cell carcinoma. One is the “angled border” that is produced by an inflammatory giant cell reaction underlying the tumor, which may falsely increase the apparent size of the tumor. The other is the “blurry border,” which is produced by large hypertrophy of the sebaceous glands surrounding the lesion. According to the literature, both artifacts can be recognized by a well-trained operator. The figure above presents the sonographic involvement of deeper layers such as the nasal cartilage and orbicularis muscles in the face is of critical importance and may change the decision about the type of surgery. Basal cell carcinoma with nasal cartilage involvement (3-dimensional reconstruction, 5- to 8-second sweep, transverse view, left nasal wing). Notice the extension of the tumor (asterisk, outlined) to the nasal cartilage region (c); d indicates dermis.

Basal cell carcinoma with involvement of the orbicularis muscle of the eyelid (m). Grayscale sonography (transverse view, right lower eyelid) shows that the tumor (asterisk) affects the muscle layer (arrows).

Basal cell carcinoma with involvement of the orbicularis muscle of the eyelid (m). Grayscale sonography (transverse view, right lower eyelid) shows that the tumor (asterisk) affects the muscle layer (arrows).

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Many feedbacks to my last post reflected radiologists’ perception of ultrasound as a low-tech, unreliable imaging device.

Ultrasounds most manifested limitation by radiologists is that its performance is too-much user-dependent. This opinion finds support in numerous clinical studies concluding that ultrasound-based assessment of a cancer patient varies with the operator.

How come that an imaging technology that is not only  low-cost, simple to operate and risk-free to the patient, but has also gained a leading position in certain domain, like obstetrics,  is perceived as the underdog when it comes  to cancer assessment? Could it be because of its positioning as a “multi-purpose” system, which requires only very basic training?

If indeed this is the case, it doesn’t require “rocket-science” to turn it around. It only needs designing dedicated ultrasound machines who offer a comprehensive solution to one specific clinical need. Using such machines will require highly skilled operators who will enjoy a superior workflow, reporting tools and proven clinical guidelines.

The unsatisfactory reality of mammography-based breast cancer screening, as evident by epidemiology data and expert-panels’ reports, opens the opportunity to transform ultrasound into a winner in the niche-market of breast cancer screening and diagnosis. It’s a significant market that justifies the investment in ultrasound systems dedicated to detection and characterisation of breast cancer lesions.

No doubt, that the ability to provide accurate and standardized interpretation of such ultrasound systems’ scans is a pre-requisite. Ultrasound-based tissue characterisation is a must for any application aiming at standardized image interpretation. A sample out-of present ultrasound-based technologies aiming at providing some level of tissue-characterisation are listed below. Recent clinical studies show promising results using these technologies. It is worth watching carefully to see if any of those could be part of a future ultrasound-based solution to breast cancer screening.

Solid Breast Lesions: Clinical Experience with US-guided Diffuse Optical Tomography Combined with Conventional US

Results: Of the 136 biopsied lesions, 54 were carcinomas and 82 were benign. The average total hemoglobin concentration in the malignant group was 223.3 μmol/L ± 55.8 (standard deviation), and the average hemoglobin concentration in the benign group was 122.5 μmol/L ± 80.6 (P = .005). When the maximum hemoglobin concentration of 137.8 μmol/L was used as the threshold value, the sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of DOT with US localization were 96.3%, 65.9%, 65.0%, 96.4%, and 76.5%, respectively. The sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of conventional US were 96.3%, 92.6%, 89.7%, 97.4%, and 93.4%, respectively. The sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of conventional US combined with DOT were 100%, 93.9%, 91.5%, 100%, and 96.3%, respectively.

Conclusion: US-guided DOT combined with conventional US improves accuracy compared with DOT alone.

Breast Lesions: Quantitative Elastography with Supersonic Shear Imaging—Preliminary Results



Results: All breast lesions were detected at Supersonic Shear Imaging. Malignant lesions exhibited a mean elasticity value of 146.6 kPa ± 40.05 (standard deviation), whereas benign ones had an elasticity value of 45.3 kPa ± 41.1 (P < .001). Complicated cysts were differentiated from solid lesions because they had elasticity values of 0 kPa (no signal was retrieved from liquid areas).

Conclusion: Supersonic Shear Imaging provides quantitative elasticity measurements, thus adding complementary information that potentially could help in breast lesion characterization with B-mode US.

 Distinguishing Benign from Malignant Masses at Breast US: Combined US Elastography and Color Doppler US—Influence on Radiologist Accuracy

Results: The Az of B-mode US, US elastography, and Doppler US (average, 0.844; range, 0.797–0.876) was greater than that of B-mode US alone (average, 0.771; range, 0.738–0.798) for all readers (P = .001 for readers 1, 2, and 3; P < .001 for reader 4; P = .002 for reader 5). When both elastography and Doppler scores were negative, leading to strict downgrading, the specificity increased for all readers from an average of 25.3% (75.4 of 298; range, 6.4%–40.9%) to 34.0% (101.2 of 298; range, 26.5%–48.7%) (P < .001 for readers 1, 2, 4, and 5; P = .016 for reader 3) without a significant change in sensitivity.

Conclusion: Combined use of US elastography and color Doppler US increases both the accuracy in distinguishing benign from malignant masses and the specificity in decision-making for biopsy recommendation at B-mode US.

Evaluation of breast lesions by contrast enhanced ultrasound: Qualitative and quantitative analysis

A 57-year-old woman with a no-palpable lesion in the outer upper quadrant of left breast. (a) Gray scale image show an indistinct, hypo-echoic lesion. (b) Contrast enhanced image obtained 35 s after contrast agent injection showing a homogeneously and hyper-enhanced lesion. (c) Micro flow image obtained 38 s after contrast agent injection showing the enhanced mass with several radial vessels (arrow). (d) The time-intensity curve analysis show the peak intensity is 145.69 (intensity/1000), time to peak is 15.08 s, ascending slope is 8.98, descending slope is 1.03, the area under the curve is 7783.34. Pathologic analyses show this is an invasive ductal carcinoma.

Results: Histopathologic analysis of the 91 lesions revealed 44 benign and 47 malignant. For qualitative analysis, benign and malignant lesions differ significantly in enhancement patterns (p < 0.05). Malignant lesions more often showed heterogeneous and centripetal enhancement, whereas benign lesions mainly showed homogeneous and centrifugal enhancement. The detectable rate of peripheral radial or penetrating vessels was significantly higher in malignant lesions than in benign ones (p < 0.001). For quantitative analysis, malignant lesions showed significantly higher (p = 0.031) and faster enhancement (p = 0.025) than benign ones, and its time to peak was significantly shorter (p = 0.002). The areas under the ROC curve for qualitative, quantitative and combined analysis were 0.910 (Az1), 0.768 (Az2) and 0.926(Az3) respectively. The values of Az1 and Az3 were significantly higher than that for Az2 (p = 0.024 and p = 0.008, respectively). But there was no significant difference between the values of Az1 and Az3 (p = 0.625).

Conclusions: The diagnostic performance of qualitative and combined analysis was significantly higher than that for quantitative analysis. Although quantitative analysis has the potential to differentiate benign from malignant lesions, it has not yet improved the final diagnostic accuracy.

 Breast HistoScanning: the development of a novel technique to improve tissue characterization during breast ultrasound

Results: In 17 normal testing volumes, 3% of isolated voxels were classified as abnormal. In 15 abnormal testing volumes, the subclassifiers differentiated between malignant and benign tissue. BHS in benign tissue showed <1% abnormal voxels in cyst, hamartoma, papilloma and benign fibrosis. The fibroadenomas differed showing <5% and <24% abnormal voxels. Abnormal voxels in cancers increased with the volume of cancer at pathology.

Conclusions: HistoScanning reliably discriminated normal from abnormal tissue and could distinguish between benign and malignant lesions.

Written by: Dror Nir, PhD

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Automated Breast Ultrasound System (‘ABUS’) for full breast scanning: The beginning of structuring a solution for an acute need!

Writer: Dror Nir, PhD

GE Healthcare announced this week the acquisition of U-Systems, Inc. U-systems has developed the first and only Automated Breast Ultrasound System (ABUS) on the market – somo•v®, to receive FDA approval as an adjunct to mammography screening for breast cancer of; “asymptomatic women, with greater than 50 percent dense breast tissue and no prior breast interventions.”

somo•v® screen shot, showing mass in upper-outer quadrant of the left breast. Image courtesy of U-Systems.

I became aware of somo•v® already in 2004, when Prof. André Grivegnée, head of the breast screening unit at Jules Bordet – European oncology center in Brussels, Belgium, invited me to participate in a technology assessment of U-Systems’ somo•v® product. On that occasion, I also shared with U-System’s developers the idea of incorporating tissue characterisation into their product, an idea which they did not take on board. There is nothing more vivid to fully understand the meaning of this acquisition for breast cancer screening then the following quote from AuntMinnie’s report “GE taps interest in ABUS with U-Systems acquisition”:  “You know you’re onto something when the big boys come calling. GE Healthcare today announced its acquisition of automated breast ultrasound (ABUS) developer U-Systems, a move that highlights the rapid evolution of ABUS from a niche technology into a promising adjunct to screening mammography. “ First savvy: The reality of medical device startups is that it doesn’t matter how real and large is the need for your technology. Until one of the big boys will adopt it, it is prone to be considered as niche technology. I discussed the potential role of ABUS in future breast screening in my recent posts: Closing the Mammography gap; Introducing smart-imaging into radiologists’ daily practice.  As noted, in recent years, several ABUS systems were developed. An intriguing question is; why did GE choose to buy the somo•v® and not one of the other systems? Why now and not 2 or 3 years ago? The answer must have to do with the fact that in September 2012, somo•v® became the first ABUS system to receive premarket approval (PMA) for its application to use the system in a breast cancer screening environment. Until then, somo·v was indicated for use as an adjunct to mammography for B-mode ultrasonic imaging of a patient’s breast when used with an automatic scanning linear array transducer or a handheld transducer. The PMA has extended somo·v’s Indication For Use (IFU) allowing a claim that it increases breast cancer detection in a certain patients population. Second savvy: Having a PMA approval for a compelling indication for use, in a significant enough patient group, will dramatically increase “big boys” interest in your product. From the information available on the FDA site, one can get an insight into U-System’s regulatory strategy. They were smart enough to be satisfied with achieving a small step; increasing the detection rate of mammography-based screening. Therefore, the same radiologist who read the mammograms also read the ultrasound image. This increases the probability that your device’s sensitivity will not be worse than that of mammography. U-Systems did not try to go all the way to become an alternative to mammography. A claim that would significantly increase the complexity of the required clinical study; e.g. will require comparison of cancer detection-rates between modalities by independent, blinded-readers. Therefore, “the device is not intended to be used as a replacement for screening mammography”.   Third savvy: The most expensive component, in time and money, in a regulatory pathway are the clinical studies. A cost-effective regulatory strategy is linked to good understanding of the market segmentation. Identifying what kind of IFU differentiates your products from its competition in a large enough niche-market is key. It will also lead to the simplest clinical-study design possible. As an entrepreneur, I cannot help congratulating U-Systems’ team for pulling through continuous hurdles to reach the point all medical device startups are hoping for. They certainly picked up the right item to focus their efforts on: i.e. PMA approval for breast cancer screening. Finally, I will reiterate my vision that embedding real-time tissue characterization in an ultrasound system, capable of performing fast and standardized full breast scanning is: a. Technologically achievable; and b. in the long-term, will be an excellent alternative to mammography for breast cancer screening. Additional readings: Two studies related to  somo•v® will be discussed at the 2012 RSNA meeting: “ A study led by Dr. Rachel Brem of George Washington University Medical Center: ABUS plus mammography finds cancer early in women with dense tissue  Brem’s study found that ABUS enabled detection of early-stage cancers in women with dense breasts, giving healthcare providers time to start early treatment. In all, 88% of cancers found by ABUS alone in a group of 15,000 women were grade 1 or 2.” “A study presented by Maryellen Giger, PhD, of the University of Chicago: ABUS boosts mammography’s performance  this study results showthat adding ABUS to mammography for women with dense breast tissue improved sensitivity by 23.3 percentage points, from 38.8% for mammography alone to 63.1% for mammography plus ABUS.” As I mentioned already, there are other ultrasound modalities out there, some are ABUS and some are not. All are adjunct to mammography screening. Related studies will also be presented during that same meeting.

UPDATE (04-Aug-2013)

Here below is a recent publication on  the use of ABUS for better detection of breast cancer in patients presented with mammographically dense breast.

Improved breast cancer detection in asymptomatic women using 3D-automated breast ultrasound in mammographically dense breasts

  • Breast Cancer Research Institute, Nova Southeastern University College of Medicine, 5732 Canton Cove, Winter Springs, FL 32708, USA


Automated breast ultrasound (ABUS)was performed in 3418 asymptomatic women with mammographically dense breasts. The addition of ABUS to mammography in women with greater than 50% breast density resulted in the detection of 12.3 per 1,000 breast cancers, compared to 4.6 per 1,000 by mammography alone. The mean tumor size was 14.3 mm and overall attributable risk of breast cancer was 19.92 (95% confidence level, 16.75 – 23.61) in our screened population. These preliminary results may justify the cost-benefit of implementing the judicious us of ABUS in conjunction with mammography in the dense breast screening population.


  • Breast ultrasound;
  • 3-dimensional sonography;
  • Breast screening;
  • Dense breast;
  • Breast cancer;
  • Cancer detection

1. Introduction

Mammographic density as an independent risk factor for developing breast cancer has been documented since the 1970’s [1]. The appearance of breast tissue is variable among women. The appearance of density on mammography is the result of the relative proportion of breast stroma, which is less radiolucent compared to fat, accounting for increased breast density. Wolfe classified breast density as an independent risk factor for breast cancer in women [2] and [3]. Approximately 70 to 80% of breast cancers occur in women with no major predictors [4][5] and [6]. Population-based screening for early detection of breast cancer is therefore the primary strategy for reducing breast cancer mortality. Mammography has been used as the standard imaging method for breast cancer screening, with reduction in breast cancer mortality [7]. Breast density significantly reduces the ability to visualize cancers on mammography. The number of missed cancers is substantially increased in mammographically dense breasts, where the sensitivity is reported as low as 30 to 48%. [8]; and the odds of developing breast cancer 17.8 times higher [9]. Hand held ultrasound (HHUS) has been used to optimize the detection of cancers in mammographically dense breasts, but is limited due to technical factors, such as breast size, considerable user variability and reproducibility, technical skill, and time constraints, precluding HHUS as an effective screening modality for breast cancer [10][11] and [12]. Kelly described the use of 3D-automated breast ultrasound (ABUS) as an adjunct to mammography in the evaluation of non-palpable breast cancers in asymptomatic women. ABUS with mammography resulted in an increase in diagnostic yield from 3.6 per 1,000 with mammography alone, to 7.2 per 1,000 by adding ABUS, resulting in a mammography miss rate of 3.6 per 1,000 [13]. However, one of the limitations of the study was that it did not isolate dense breasts as an independent risk factor for developing breast cancer, where the detection rate should be expected to be higher. ABUS is FDA-approved in the United States for screening of women with dense breast parenchyma [14]. The purpose of this study was to demonstrate that ABUS increases the detection of non-palpable breast cancers in mammographically dense breasts when used as an adjunct diagnostic modality in asymptomatic women. This resulted in the subsequent detection of cancers missed by mammography of smaller size and stage, justifying the basis for the judicious use of implementing ABUS in conjunction with mammography in the dense breast screening population. The tabulated data was extrapolated based on known mammography screening utilization to show a cost-benefit of additional ABUS as a population based screening method.

2. Methods

2.1. Selection of participants

This study and the use of patient electronic health records were approved by an ethics committee appointed by the institute Board of Directors. The study design included two study groups, the control and test groups, in successive years. Each group was followed prospectively for 1 year. The control group consisted of women screened by digital mammography alone and stratified for breast density based on a Wolf classification of 50% or greater breast density (defined as the ‘mammographically dense breast’ for the purpose of this study). The second group consisted of women initially screening by digital mammography as having mammographically dense breasts, followed by automated breast ultrasound (ABUS). Each group was carefully selected on the basis of breast density and having no major pre-existing predictors of breast cancer, such personal or family history of breast cancer, or BRCA gene positive. In addition, the test group patients were not included in the screening group so as to eliminate impact on the results of the test group patients. The control group consisting of 4076 asymptomatic women designated as Wolf classification of 50% or greater breast density underwent stand-alone screening digital mammography between January 2009 and December 2009 using digital mammography (Selenia, Hologic Inc., Bedford, MA USA). The sensitivity, specificity, positive predictive value, and negative predictive value for biopsy recommendation were determined, in addition to data collection regarding the size and stage of cancers missed by mammography. The test group, consisting of 3418 asymptomatic women designated as Wolf classification of 50% or greater breast density, underwent stand-alone screening digital mammography between January 2010 and May 2011 using digital mammography (Selenia, Hologic Inc., Bedford, MA USA). This was followed by automated whole breast ultrasound (Somo-V. U-Systems, Sunnyvale, CA USA). The mammography-alone results were not used as control results in order to eliminate potential bias introduced by ABUS results on the mammography interpretations. In addition, mammography results were interpreted independently from ABUS results so as not to introduce bias. The sensitivity, specificity, positive predictive value, and negative predictive value for biopsy recommendation were determined, in addition to derived statistical data regarding the relative risk, and odds ratio for developing breast cancer.

2.2. Assessment of mammographic density

Mammographic density was assessed independently by radiologists on a dedicated mammography viewing workstation equipped with 5-Megapixel resolution. The radiologists were FDA-qualified in mammography, with at least 10 years experience in breast ultrasound, 24 months of which included ABUS. Two radiologists interpreted both the mammography and ABUS examinations under identical viewing conditions of 5-Megapixel resolution. The mammograms and ABUS studies were double read by two radiologists, with final consensus determination for each case. Mammograms were evaluated according to one of five categories of density (0%, 1 to 24%, 25 to 49%, 50 to 74%, and 75 to 100%) and only mammograms with breast density of 50% or greater were included in the control and test study groups.

2.3. 3D-Automated breast ultrasound evaluation

3D-Automated Breast Ultrasound (ABUS) is a computer-based system for evaluating the whole breast. The whole breast ultrasound system (Somo-V, U-Systems, Sunnyvale, CA USA) was used in combination with a 6 to 14 MHz broadband mechanical transducer attached to a rigid compression plate and arm, producing over 300 images per image acquisition obtained as coronal sweeps from the skin to the chest wall. The mechanical arm controls transducer speed and position, while a trained ultrasound technologist maintains appropriate contact pressure and vertical orientation to the skin. Interpretation and reporting time for an experienced radiologist is approximately 10 minutes per examination. The radiologist has cine functionality to simultaneously view breast images in the coronal, sagittal, and axial imaging planes.

2.4. Data collection

ABUS scan data was collected for location and size of breast masses and recorded in a radial or clock orientation consistent with American College of Radiology reporting lexicon. Studies were reported according to the American College of Radiology Breast Imaging Reporting and Data System (BI-RADS) six-point scale (0=incomplete, needs additional assessment; 1=normal; 2=benign; 3=probably benign; 4=suspicious; 5=highly suggestive of malignancy) [15] and [16]. For BI-RADS scores of 1, 2, and 3 on ABUS, patients were followed prospectively for 1 year to exclude cancers missed on both mammography and ABUS. For BI-RADS scores of 4 and 5, stereotactic hand held ultrasound (HHUS) biopsy was performed using 14 gauge or larger percutaneous biopsy. HHUS was employed because ABUS is presently not equipped with biopsy capability. If a benign non-high risk lesion was diagnosed, such as simple breast cysts, no further tissue sampling was performed. All non-cystic lesions were biopsied. Cystic lesions were identified as anechoic, thin walled lesions with posterior acoustic enhancement. All pathology proven breast malignancies were further staged using contrast volumetric/whole breast MR imaging (1.5T HDe Version 15.0/M4 with VIBRANT software, GE Medical Systems, Waukesha, WI USA.) with computer assisted detection (CADStream software, Merge Healthcare, Belleview WA USA). A final pathological stage was assigned by the pathologists in the usual manner in accordance with the American Joint Committee on Cancer (AJCC) TNM system guidelines. The pathologists were blinded to patient participation in the study and the method of cancer detection.

2.5. Statistical analysis

Calculations were made of the sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), relative risk, odds risk, and attributable risk of breast cancer using MedCal version 12.2.1 software. Exact 95% confidence intervals (CI) were calculated for diagnostic yield. Statistical methods involved the Chi-square test statistic, which was used to compare the number of cancers detected by ABUS, based on the size of cancer. P-values of less than .05 were considered to indicate statistical significance. Attributable risk (AR) was calculated according to the following formula: AR=(RR − 1)Pc ÷ RR, where RR denotes relative risk of greater than 50%, and Pc prevalence of density of greater than 50% in case patients[17][18] and [19].

3. Results

Comparable interobserver diagnostic reliability (Kappa value of 0.98) was observed with mammography and ABUS examinations. In the control group (N=4076), the median age of participants with breast cancer (N=19) at the time of biopsy was 54 years, distributed as follows: 26% (5 out of 19) cancers occurred in women younger than age 50; 63% (12 out of 19) in women 50 to 69 years; and 11% (2 out of 19) over the age of 70 years. All cancers (N=19) were biopsy proven invasive ductal carcinoma. The sensitivity and specificity of stand-alone digital mammography were 76.00% (95% CI: 54.87% – 90.58%) and 98.2% (95% CI: 97.76% – 98.59%). The positive predictive value was 20.43% (95% CI: 12.78% – 30.05%) with a breast cancer prevalence rate of 0.60% (95% CI: 12.78% – 30.05%). The cancer detection rate was 4.6 per 1,000, with mean tumor size detected by mammography (N=19) of 21.3 mm. The average size of missed breast cancer (N=6) was 22.3 mm. The node positivity rate was 5% (1 of 19 cases). In the ABUS study group (N=3418), the median age of participants with breast cancer (N=42) at the time of biopsy was 57 years, distributed as follows: 17% (7 out of 42) cancers occurred in women younger than age 50; 64% (27 out of 42) in women 50 to 69 years; and 19% (8 out of 42) over the age of 70 years. The sensitivity and specificity of ABUS were 97.67% (95% CI: 87.67% – 99.61%) and 99.70%, (95% CI=99.46% – 99.86%), respectively, in mammographically dense breasts. The positive predictive value of ABUS was 80.77% (95% CI=67.46% – 90.36%), with a breast cancer prevalence rate of 1.25% (95% CI: 0.91% – 1.69%). The odds ratio of breast cancer in mammographically dense breasts determined by ABUS was 2.65 (95% CI: 1.54 – 4.57; P=0.0004). The cancer detection rate was 12.3 per 1,000. A 2.6-fold increase in cancer detection rate was observed between ABUS added to digital screening mammography compared to stand-alone digital screening mammography. Invasive breast cancer accounted for 81% (42 out of 52) solid breast masses detected by ABUS, of which 93% (39 out of 42) were invasive ductal carcinomas, and 7% (3 out of 42) were invasive lobular carcinomas. The mean tumor size detected by ABUS in patients with breast cancer (N=42) was 14.3 mm, distributed as follows: Stage 1A disease accounted for 83% (35 out of 42) of cases; 12% were Stage 2A (5 out of 42), and 5% were Stage 3A (2 out of 42). Stage 3A disease was associated with multifocal disease in both cases, one of which also was Level 1 axillary lymph node positive. The node positivity rate was 2% (1 in 42) of cases. The false positive rate of ABUS was 19.3%, with a negative predictive value of 99.97% (95% CI 99.83% – 100.00%). The pathologies associated with false positive results (N=10) were fibroadenomas and atypical epithelial neoplasms. We also used our data to extrapolate the theoretical cost-benefit of ABUS screening applied to a large screening population in the United States. Our analysis relied on the following assumptions: (1) Global Centers for Medicare and Medicaid reimbursement rate of breast ultrasound of $71 [20]; and (2) Estimated mean doubling time of a missed cancer of 250 days at the 95th percentile [21] and [22]. According to previously cited cancer kinetics models, a missed breast cancer should be clinically evident within 9 months[23]. When we considered the mean breast cancer size in our positive test subject group, 14.3 mm (N=42), we extrapolated a theoretical missed cancer size of 29.2 mm at 9 months in mammographically dense breasts, representative of Stage 2 or greater disease. In control subjects, a mean breast cancer size of 22.3 mm was consistent with stage 2 breast cancer. Incremental treatment cost assumptions, based on the global Centers for Medicare and Medicaid reimbursement rate between Stage 1 and Stage 2 breast cancer, were $24,002 and $34,469, respectively, for a cost differential of $10,467 [24]. Accordingly, the aggregate costs of screening 3418 ABUS patients in this study were $239,260, compared to the estimated aggregate costs of additional treatment in 26 potentially missed cancers (based on previously noted theoretical assumptions) of $275,557 based on a cancer miss rate of 0.77% (or 7.7 per 1,000).

4. Discussion

Table 1 shows the clinical indications for ordering an ABUS examination. Table 2 shows the distribution of breast cancer size according to age in the control and test study groups. The test group showed no statistical difference between size of the cancer and patient age at presentation. A significant increase in tumor size in the over 70 patients in control subjects was attributed to the more advanced tumor stage at presentation.Table 3 shows that stand-alone digital mammography was less sensitive than ABUS in breast cancer detection, with a 4-fold increase in positive predictive value of ABUS compared to stand-alone mammography in dense breasts. Our results showed that mammographic density of 50% or more was associated with an increased risk of breast cancer and resulted in a significant miss rate in asymptomatic women. Table 4 shows a statistically significant age-related attributable risk of developing breast cancer for mammographic density of 50% or greater. These observations are consistent with other studies which have shown an increased risk of breast cancer in dense breasts following negative mammography screening [2],[3][8] and [9]. We observed that breast cancer risk was highest in patients over age 70, where increased breast density was associated with an attributable risk of 29.6 (95% CI, 21.5 – 40.8). Fig. 1 shows box plots comparing case patients and control subjects according to age, with tumor sizes shown as a function of the odds ratio, relative risk, and attributable risk for each age category.

Table 1. Clinical criteria for ABUS screening
• As a supplement to mammography, screening for occult cancers in certain populations of women (such as those with dense fibroglandular breasts and/or with elevated risk of breast cancer);
• Imaging evaluation of non-palpable masses in women under 30 years of age who are not at high risk for development of breast cancer, and in lactating and pregnant women; and
• BI-RADS (American College of Radiology Breast Imaging Reporting and Data System) scoring classification class III, heterogeneously dense, with 50% to 74% or 75% to 100% breast density on mammography, without palpable mass.
Table 2. Breast cancer size according to method detection


Table 3. Detection of breast cancer according to method

Table 4. Risk of breast cancer according to method detection


Fig. 1. Breast Cancer Staging and Risk Assessment by Screening Method Detection. Box plots comparing case patients and control subjects according to age (boxes A through D). Tumor sizes are shown as a function of the odds ratio, relative risk, and attributable risk for each age category. Bars represent the highest and lowest observed values with respect to individual variables (individually labeled with arrows).


Our study also showed that 3D-Automated Breast Ultrasound (ABUS) was an effective screening modality in mammographically dense breasts. Our extrapolated data suggest a breast cancer miss rate of 7.7 per 1,000 in mammographically dense breasts in asymptomatic women, which is higher compared to the cancer miss rate of 3.6 per 1,000 reported by Kelly using ABUS [13]. We attribute the increased breast cancer miss rate due to breast density, which was isolated as the principal risk factor in our study. Other studies have shown that the attributable risk of breast cancer for a mammographic density of 50% or greater was 40% for all cancers detected less than 12 months after a negative screening mammogram, and as high as 50% in women less than the age of 50. This marked increase in the risk of breast cancer associated with mammographic density of 50% or greater up to 12 months following screening directly reflects cancers that were present at the time of screening but went undetected due to masking by dense breast parenchyma [25],[26][27][28] and [29]. In the final analysis, there is the issue of the theoretical cost-benefit of adding ABUS screening to mammography in an otherwise healthy population. The importance of screening mammographically dense breasts with ABUS has particular relevance based on the small size and early stage of breast cancers. Our study showed a mean tumor size of 14.3 mm, representing stage 1 disease, which was present in 81% of patients. From our data, we derived theoretical population-based costs as a basis for the cost-benefit of ABUS in the United States population. Our study compared the incremental costs of screening versus the costs of added treatment related to a change in the staging of missed cancers from Stage 1 to Stage 2. The costs of additional treatment outweighed the costs of screening by $32,808, which calculated to $9.60 added healthcare cost per patient in the 3418 participants in the study. In the United States, 48 million mammograms were performed annually, with a reported estimated miss rate of 10% [30]. When comparing control versus test patients, our study suggests a theoretical miss rate of 7.7 cancers per 1,000 mammograms, or 0.77%, which is considerably lower than the reported missed rate of 10%. Based on these theoretical assumptions, annual added ABUS screening of the entire U.S. population would cost $3.40-billion. However, in actual practice, ABUS would be used only in the mammographically dense breast, which would potentially reduce the screening costs by at least a factor of 0.8, bringing the cost closer to $2.72-billion. By contrast, the incremental costs of added treatment associated with stage 2 compared to stage 1 breast cancer in the U.S. population would be $3.82-billion, assuming a conservative cost basis of $10,467 per patient.. The cost-benefit of early detection of stage 1 disease results in a theoretical per capital annual cost savings of $22.75 per screened patient in the U.S. population, according to our model. However, we have no actual or derived data to support improved breast cancer mortality with the addition of ABUS as a universal screening modality. This is one of the major limitations of our study because actuarial analyses used to justify screening modalities are typically based on mortality statistics. With respect to five year survival statistics between stage 1 and stage 2 breast cancers, of 98% and 80%, respectively, one could construe the potential for a theoretical quality-of-life benefit based on judicious ABUS screening. Another limitation of our study is the relatively small screening population used in our study, emphasizing the need for continued research in order to validate ABUS as a viable and cost-effective population-based screening modality, which should be stratified for other risk factors for breast cancer, such as: personal or family history of breast cancer, BRCA genetic results, environmental factors (late parity, previous exposure to ionizing radiation, exogenous estrogen, smoking, and alcohol use), early menarche/late menopause, and ethnic/racial differences. At most imaging centers, mammography is the only screening method for breast cancer detection. Our study corroborates with the data derived from other studies that the principal mechanism for breast cancer in dense breast parenchyma is not rapid growth, but rather, the masking of coincident cancers that are missed on screening mammograms [9]. These findings further suggest that the addition of mammographic screening in patients with dense breast parenchyma is likely not to increase diagnostic yield in the detection of breast cancers. Therefore, emphasis should be placed on alternative imaging techniques for such women. To conclude, our study of a small representative dense breast screening population showed that the addition of ABUS was more effective than digital mammography alone. This study provides a platform for using ABUS as cost-effective approach to breast cancer detection in the judicious screening of asymptomatic women with excessive mammographic density, in whom the greatest risk is between screening mammography examinations.


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Corresponding author. Breast Cancer Research Institute, Nova Southeastern University College of Medicine, 5732 Canton Cove, Winter Springs, FL 32708, USA. Tel.: 1 407 699 7787.

Copyright © 2013 Elsevier Inc. All rights reserved.

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The unfortunate ending of the Tower of Babel construction project and its effect on modern imaging-based cancer patients’ management

The story of the city of Babel is recorded in the book of Genesis 11 1-9. At that time, everyone on earth spoke the same language.

Picture: Pieter Bruegel the Elder: The Tower of Babel_(Vienna)

It is probably safe to assume that medical practitioners at that time were reporting the status of their patients in a standard manner. Although not mentioned, one might imagine that, at that time, ultrasound or MRI scans were also reported in a standard and transferrable manner. The people of Babel noticed the potential in uniform communication and tried to build a tower so high that it would  reach the gods. Unfortunately, God did not like that, so he went down (in person) and confounded people’s speech, so that they could not understand each another. Genesis 11:7–8.

This must be the explanation for our inability to come to a consensus on reporting of patients’ imaging-outcome. Progress in development of efficient imaging protocols and in clinical management of patients is withheld due to high variability and subjectivity of clinicians’ approach to this issue.

Clearly, a justification could be found for not reaching a consensus on imaging protocols: since the way imaging is performed affects the outcome, (i.e. the image and its interpretation) it takes a long process of trial-and-error to come up with the best protocol.  But, one might wonder, wouldn’t the search for the ultimate protocol converge faster if all practitioners around the world, who are conducting hundreds of clinical studies related to imaging-based management of cancer patients, report their results in a standardized and comparable manner?

Is there a reason for not reaching a consensus on imaging reporting? And I’m not referring only to intra-modality consensus, e.g. standardizing all MRI reports. I’m referring also to inter-modality consensus to enable comparison and matching of reports generated from scans of the same organ by different modalities, e.g. MRI, CT and ultrasound.

As developer of new imaging-based technologies, my personal contribution to promoting standardized and objective reporting was the implementation of preset reporting as part of the prostate-HistoScanning product design. For use-cases, as demonstrated below, in which prostate cancer patients were also scanned by MRI a dedicated reporting scheme enabled matching of the HistoScanning scan results with the prostate’s MRI results.

The MRI reporting scheme used as a reference is one of the schemes offered in a report by Miss Louise Dickinson on the following European consensus meeting : Magnetic Resonance Imaging for the Detection, Localisation, and Characterisation of Prostate Cancer: Recommendations from a European Consensus Meeting, Louise Dickinson a,b,c,*, Hashim U. Ahmed a,b, Clare Allen d, Jelle O. Barentsz e, Brendan Careyf, Jurgen J. Futterer e, Stijn W. Heijmink e, Peter J. Hoskin g, Alex Kirkham d, Anwar R. Padhani h, Raj Persad i, Philippe Puech j, Shonit Punwani d, Aslam S. Sohaib k, Bertrand Tomball,Arnauld Villers m, Jan van der Meulen c,n, Mark Emberton a,b,c,


Image of MRI reporting scheme taken from the report by Miss Louise Dickinson

The corresponding HistoScanning report is following the same prostate segmentation and the same analysis plans:

Preset reporting enabling matching of HistoScanning and MRI reporting of the same case.

It is my wish that already in the near-future, the main radiology societies (RSNA, ESR, etc..) will join together to build the clinical Imaging’s “Tower of Babel” to effectively address the issue of standardizing reporting of imaging procedures. This time it will not be destroyed…:-)

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Knowing the tumor’s size and location, could we target treatment to THE ROI by applying imaging-guided intervention?

Knowing the tumor’s size and location, could we target treatment to THE ROI by applying imaging-guided intervention?

Author: Dror Nir, PhD


Advances in techniques for cancer lesions’ detection and localisation [1-6] opened the road to methods of localised (“focused”) cancer treatment [7-10].  An obvious challenge on the road is reassuring that the imaging-guided treatment device indeed treats the region of interest and preferably, only it.

A step in that direction was taken by a group of investigators from Sunnybrook Health Sciences Centre, University of Toronto, Ontario, Canada who evaluate the feasibility and safety of magnetic resonance (MR) imaging–controlled transurethral ultrasound therapy for prostate cancer in humans [7]. Their study’s objective was to prove that using real-time MRI guidance of HIFU treatment is possible and it guarantees that the location of ablated tissue indeed corresponds to the locations planned for treatment. Eight eligible patients were recruited.


The setup


Treatment protocol


The result


“There was excellent agreement between the zone targeted for treatment and the zone of thermal injury, with a targeting accuracy of ±2.6 mm. In addition, the temporal evolution of heating was very consistent across all patients, in part because of the ability of the system to adapt to changes in perfusion or absorption properties according to the temperature measurements along the target boundary.”


Technological problems to be resolved in the future:

“Future device designs could incorporate urinary drainage during the procedure, given the accumulation of urine in the bladder during treatment.”

“Sufficient temperature resolution could be achieved only by using 10-mm-thick sections. Our numeric studies suggest that 5-mm-thick sections are necessary for optimal three-dimensional conformal heating and are achievable by using endorectal imaging coils or by performing the treatment with a 3.0-T platform.”

Major limitation: “One of the limitations of the study was the inability to evaluate the efficacy of this treatment; however, because this represents, to our knowledge, the first use of this technology in human prostate, feasibility and safety were emphasized. In addition, the ability to target the entire prostate gland was not assessed, again for safety considerations. We have not attempted to evaluate the effectiveness of this treatment for eradicating cancer or achieving durable biochemical non-evidence of disease status.”


  1. SIMMONS (L.A.M.), AUTIER (P.), ZATURA (F.), BRAECKMAN (J.G.), PELTIER (A.), ROMICS (I.), STENZL (A.), TREURNICHT (K.), WALKER (T.), NIR (D.), MOORE (C.M.), EMBERTON (M.). Detection, localisation and characterisation of prostate cancer by Prostate HistoScanning.. British Journal of Urology International (BJUI). Issue 1 (July). Vol. 110, Page(s): 28-35
  2. WILKINSON (L.S.), COLEMAN (C.), SKIPPAGE (P.), GIVEN-WILSON (R.), THOMAS (V.). Breast HistoScanning: The development of a novel technique to improve tissue characterization during breast ultrasound. European Congress of Radiology (ECR), A.4030, C-0596, 03-07/03/2011.
  3. Hebert Alberto Vargas, MD, Tobias Franiel, MD,Yousef Mazaheri, PhD, Junting Zheng, MS, Chaya Moskowitz, PhD, Kazuma Udo, MD, James Eastham, MD and Hedvig Hricak, MD, PhD, Dr(hc) Diffusion-weighted Endorectal MR Imaging at 3 T for Prostate Cancer: Tumor Detection and Assessment of Aggressiveness. June 2011 Radiology, 259,775-784.
  4. Wendie A. Berg, Kathleen S. Madsen, Kathy Schilling, Marie Tartar, Etta D. Pisano, Linda Hovanessian Larsen, Deepa Narayanan, Al Ozonoff, Joel P. Miller, and Judith E. Kalinyak Breast Cancer: Comparative Effectiveness of Positron Emission Mammography and MR Imaging in Presurgical Planning for the Ipsilateral Breast Radiology January 2011 258:1 59-72.
  5. Anwar R. Padhani, Dow-Mu Koh, and David J. Collins Reviews and Commentary – State of the Art: Whole-Body Diffusion-weighted MR Imaging in Cancer: Current Status and Research Directions Radiology December 2011 261:3 700-718
  6. Eggener S, Salomon G, Scardino PT, De la Rosette J, Polascik TJ, Brewster S. Focal therapy for prostate cancer: possibilities and limitations. Eur Urol 2010;58(1):57–64).
  7. Rajiv Chopra, PhD, Alexandra Colquhoun, MD, Mathieu Burtnyk, PhD, William A. N’djin, PhD, Ilya Kobelevskiy, MSc, Aaron Boyes, BSc, Kashif Siddiqui, MD, Harry Foster, MD, Linda Sugar, MD, Masoom A. Haider, MD, Michael Bronskill, PhD and Laurence Klotz, MD. MR Imaging–controlled Transurethral Ultrasound Therapy for Conformal Treatment of Prostate Tissue: Initial Feasibility in Humans. October 2012 Radiology, 265,303-313.
  8. Black, Peter McL. M.D., Ph.D.; Alexander, Eben III M.D.; Martin, Claudia M.D.; Moriarty, Thomas M.D., Ph.D.; Nabavi, Arya M.D.; Wong, Terence Z. M.D., Ph.D.; Schwartz, Richard B. M.D., Ph.D.; Jolesz, Ferenc M.D.  Craniotomy for Tumor Treatment in an Intraoperative Magnetic Resonance Imaging Unit. Neurosurgery: September 1999 – Volume 45 – Issue 3 – p 423
  9. Medel, Ricky MD,  Monteith, Stephen J. MD, Elias, W. Jeffrey MD, Eames, Matthew PhD, Snell, John PhD, Sheehan, Jason P. MD, PhD, Wintermark, Max MD, MAS, Jolesz, Ferenc A. MD, Kassell, Neal F. MD. Neurosurgery: Magnetic Resonance–Guided Focused Ultrasound Surgery: Part 2: A Review of Current and Future Applications. October 2012 – Volume 71 – Issue 4 – p 755–763
  10. Bruno Quesson PhD, Jacco A. de Zwart PhD, Chrit T.W. Moonen PhD. Magnetic resonance temperature imaging for guidance of thermotherapy. Journal of Magnetic Resonance Imaging, Special Issue: Interventional MRI, Part 1, Volume 12, Issue 4, pages 525–533, October 2000

Writer: Dror Nir, PhD


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Author and Curator: Dror Nir, PhD


That is the question…

We are all used to clichés such as “seeing is believing”, “seeing is knowing”, “don’t be blind” and so on. Out of our seven (natural and supernatural) senses we tend to use and trust our eyes the most. Especially, when it comes to learning, accumulation of experience and acceptance of information as correct. On the other hand, we are taught from childhood to be aware of illusions and not to judge according to looks but rather according to matter. The problem is, does one recognise the substance inside an image? To answer this, a wide-ranging discipline of image interpretation was developed alongside with imaging technology. In order not to fatigue the innocent reader, I’ll review the state of the art of imaging in medicine in subsequent posts, each dedicated to a specific modality. This post is dedicated to…

Current main trends in ultrasound imaging in cancer patients’ management;

The most used imaging modality in medicine is ultrasound. This is due to the fact that it is noninvasive, practically harmless, relatively inexpensive and fairly accessible; i.e. everyone can operate it, even a layman! No formal training or certification is required!

Interesting enough, ultrasound is labeled by the regulatory agencies, FDA and CE, as a diagnostic medical device! This is real demonstration of the aforementioned tendency to believe our eyes, even if these eyes do not see well or the brain behind them is lacking the experience required for ultrasound image interpretation.

Since “ultrasound imaging in medicine” is the subject of many text books and articles I found it  appropriate, for the sake of this post, simply  to refer the reader to Wikipedia’s page (http://en.wikipedia.org/wiki/Medical_ultrasonography) on ultrasound in medicine: “Diagnostic Sonography (ultrasonography) is an ultrasound-based diagnostic imaging technique used for visualizing subcutaneous body structures including tendonsmuscles, joints, vessels and internal organs for possible pathology or lesionsObstetric sonography is commonly used during pregnancy and is widely recognized by the public. In physics, the term “ultrasound” applies to all sound waves with a frequency above the audible range of normal human hearing, about 20 kHz. The frequencies used in diagnostic ultrasound are typically between 2 and 18 MHz.”

When it comes to cancer patients’ management, ultrasound provides real-time imaging of body organs at a relatively cost effective workflow. However, it suffers from lack of sensitivity and specificity, especially if the investigator is still fairly inex­perienced. Therefore, no diagnosis is confirmed without biopsy of the suspected lesion discovered during the ultrasound scan. As mentioned in my previous post; identification of suspicious lesions in the prostate during TRUS is so inconclusive that in order to reach diagnosis biopsies are taken randomly.

Did we hit the target?

To improve prostate cancer detection, various biopsy strategies to increase the diagnostic yield of prostate biopsy have been devised: sampling of visually abnormal areas; more lateral placement of biopsies; anterior biop­sies; and obtaining an increased number of cores, with up to 45 biopsy cores [1-5].

In recent years, new features such as 3D and contrast-enhanced sonography, elastography and HistoScanning were added to the basic video image in order to improve the quality of ultrasound based investiga­tion of cancer patients.

3-D Sonography.

3-D ultrasound allows si­multaneous biplanar imaging of the organ with com­puter reconstructions providing a coronal plane as well as a rendered 3-D image. This promises to improve the detection and pre-clinical grading of cancer lesions. Still, the interpretation is very much “image quality” and “user experience” dependent.

3D imaging of breast using ABUS by Siemens; using the coronal view to better investigate a lesion.



3D imaging of breast using Voluson 730 by GE; three planes are presented for review by the radiologist.



 Contrast-Enhanced Sonography.

Using intravenous micro-bubble agents in combination with color and pow­er Doppler imaging contributes to increase in the signal obtained in areas of increased vascularity. The underlying assumption is that vascularization in the tumor’s area will be more pronounced than in normal tissue. Hot off the press: The UK National Institute for Health and Clinical Excellence (NICE) has published guidance that supports the use of contrast-enhanced ultrasound with Bracco’s SonoVue ultrasound contrast agent for the diagnosis of liver cancer [6].  The main use of contrast-enhanced ultrasound is directing biopsies to the “most suspicious” areas; i.e. those who presents higher vascularity. Never­theless, in reported clinical studies [7] targeted biopsies’ sensitivity on contrast-enhanced ultrasound was only 68%.



Elastography is an imaging technique that evaluates the elasticity of the tissue. The underlying assumption is that tumors present greater stiffness than normal tissue and therefore will be characterized by limited compressibility. The first person to introduce this concept was  Professor Jonathan Ophir, University of Huston, Texas [http://www.uth.tmc.edu/schools/med/rad/elasto/]:
Estimation of differences in lesions’ stiffness relies  on computing the level of correlation between consecutive imaging frames while the tissue that is being imaged is subjected to changing compression, usually applied by the sonographer who manipulates the ultrasound probe. Since malignant and benign lesions exhibit similar elasticity, elastography is not suitable for lesion characterisation. Therefore, as in the previous example, elastography’s main use is identifying suspicious areas in which to take biopsies [8, 9].  Furthermore, users’ experiences related to elastography reveal a lot of controversy.  For example, according to Prof. Bruno Fornage of MD. Anderson [http://www.auntminnie.com/index.aspx?sec=sup&sub=wom&pag=dis&ItemID=99028]; “current commercially available scanners are confounded by a lack of intraobserver reliability, so that it’s not unusual to produce an opposite result on repeat testing a few seconds later”. “There are very few evidence-based non-industry sponsored studies reporting substantial superiority [of elastography] over standard grayscale ultrasound,” he said. “In fact, a sensitivity of 82% in the diagnosis of breast cancer has been reported for elastography, versus 94% for conventional grayscale ultrasound. More disturbing is that even if the technology of elastography worked flawlessly, the huge overlap in breast pathology between very firm solid benign lesions and less firm malignancies gives this technology no practical place in the differential diagnosis of solid breast masses.”



HistoScanning™ is a novel ultrasound-based software technology that utilizes advanced tissue characterization algorithms to address the clinical requirements for tissue characterization. It visualizes the position and extent of tissue suspected of being malignant in the target organ. In this respect its design is unique and superior to other ultrasound based-technologies [10, 11]. HistoScanning’s first clinically available application (since 2009) is in the management of prostate cancer patients.



HistoScanning indicating suspicious lesions superimposed on 3-D ultrasound of the prostate. The three imaging plans and 3D reconstruction of the segmented prostate are presented.



 To conclude; if we are looking to improve the current state of the art in ultrasound-based cancer patients’ management we should strive to introduce systems which will enable the medical practitioners to rule in or rule out suspicious lesions at imaging before they biopsy them. Using ultrasound just as a tool for directing biopsies as done today is not enough. Indeed, this requires capability of ultrasound-based tissue characterisation in addition to detection of ultrasound-based abnormality (i.e. circumstantial evidence for cancer). To-date, the only available system that bears the promise to provide such improvement is HistoScanning. Obviously, the level of confidence in the Negative Predictive Value of HistoScanning and future systems alike must be built to become high enough to provide the medical practitioner the reassurance and comfort that he is not missing any significant cancer by not taking a biopsy. Such confidence can only be built by subjecting these systems (i.e. HistoScanning and alike) to properly designed clinical studies and, not less important, by reporting the experience of early adopters who will test them in a controlled routine use.



  1. Flanigan RC, Catalona WJ, Richie JP, Ah-mann FR, Hudson MA, Scardino PT, de-Kernion JB, Ratliff TL, Kavoussi LR, Dalkin BL: Accuracy of digital rectal examination and transrectal ultrasonography in localiz­ing prostate cancer: results of a multicenter clinical trial of 6,630 men. J Urol 1994; 152: 1506–1509.
  2. Eichler K, Hempel S, Wilby J, Myers L, Bach­mann LM, Kleijnen J: Diagnostic value of systematic biopsy methods in the investiga­tion of prostate cancer: a systematic review. J Urol 2006; 175: 1605–1612.
  3. Delongchamps NB, de la Roza G, Jones R, Jumbelic M, Haas GP: Saturation biopsies on autopsied prostates for detecting and charac­terizing prostate cancer. BJU Int 2009; 10: 49–54.
  4. Rifkin MD, Dähnert W, Kurtz AB: State of the art: endorectal sonography of prostate gland. AJR Am J Roentgenol 1990; 154: 691– 700.
  5. Chrouser KL, Lieber MM: Extended and sat­uration needle biopsy. Curr Urol Rep 2004; 5: 226–230.
  6. http://www.auntminnieeurope.com/index.aspx?sec=nws&sub=rad&pag=dis&ItemID=607068&wf=284
  7. Yi A, Kim JK, Park SH, Kim KW, Kim HS, Kim JH, Eun HW, Cho KS: Contrast-en­hanced sonography for prostate cancer de­tection in patients with indeterminate clini­cal findings. Am J Roentgenol 2006; 186: 1431–1435.
  8. König K, Scheipers U, Pesavento A, Lorenz A, Ermert H, Senge T: Initial experiences with real-time elastography guided biopsies of the prostate. J Urol 2005; 174: 115–117.
  9. 32 Pallwein L, Mitterberger M, Struve P, Hor-ninger W, Aigner F, Bartsch G, Gradl J, Schurich M, Pedross F, Frauscher F: Com­parison of sonoelastography guided biopsy with systematic biopsy: impact on prostate cancer detection. Eur Radiol 2007; 17: 2278– 2285.
  10. SALOMON (G.), SPETHMANN (J.), BECKMANN (A.), AUTIER (P.), MOORE (C.), DURNER (L.), SANDMANN (M.), HASE (A.), SCHLOMM (T.), MICHL (U.), HEINZER (H.), GRAFEN (M.), STEUBER (T.).Accuracy of HistoScanning for the prediction of a negative surgical margin in patients undergoing radical prostatectomy. Published online in British Journal of Urology International (BJUI). 09/08/2012.
  11. SIMMONS (L.A.M.), AUTIER (P.), ZATURA (F.), BRAECKMAN (J.G.), PELTIER (A.), ROMICS (I.), STENZL (A.), TREURNICHT (K.), WALKER (T.), NM (D.), MOORE (C.M.), EMBERTON (M.).  Detection, localisation and characterisation of prostate cancer by Prostate Hist°Scanning; Published in British Journal of Urology International (BJUI). Issue 1 (July). Vol 110, P 28-35.


 Written by Dror Nir

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