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Archive for the ‘Medical Imaging Technology, Image Processing/Computing, MRI, CT, Nuclear Medicine, Ultra Sound’ Category


That is the question…

Anyone who follows healthcare news, as I do , cannot help being impressed with the number of scientific and non-scientific items that mention the applicability of Magnetic Resonance Imaging (‘MRI’) to medical procedures.

A very important aspect that is worthwhile noting is that the promise MRI bears to improve patients’ screening – pre-clinical diagnosis, better treatment choice, treatment guidance and outcome follow-up – is based on new techniques that enables MRI-based tissue characterisation.

Magnetic resonance imaging (MRI) is an imaging device that relies on the well-known physical phenomena named “Nuclear Magnetic Resonance”. It so happens that, due to its short relaxation time, the 1H isotope (spin ½ nucleus) has a very distinctive response to changes in the surrounding magnetic field. This serves MRI imaging of the human body well as, basically, we are 90% water. The MRI device makes use of strong magnetic fields changing at radio frequency to produce cross-sectional images of organs and internal structures in the body. Because the signal detected by an MRI machine varies depending on the water content and local magnetic properties of a particular area of the body, different tissues or substances can be distinguished from one another in the scan’s resulting image.

The main advantages of MRI in comparison to X-ray-based devices such as CT scanners and mammography systems are that the energy it uses is non-ionizing and it can differentiate soft tissues very well based on differences in their water content.

In the last decade, the basic imaging capabilities of MRI have been augmented for the purpose of cancer patient management, by using magnetically active materials (called contrast agents) and adding functional measurements such as tissue temperature to show internal structures or abnormalities more clearly.

 

In order to increase the specificity and sensitivity of MRI imaging in cancer detection, various imaging strategies have been developed. The most discussed in MRI related literature are:

  • T2 weighted imaging: The measured response of the 1H isotope in a resolution cell of a T2-weighted image is related to the extent of random tumbling and the rotational motion of the water molecules within that resolution cell. The faster the rotation of the water molecule, the higher the measured value of the T2 weighted response in that resolution cell. For example, prostate cancer is characterized by a low T2 response relative to the values typical to normal prostatic tissue [5].

T2 MRI pelvis with Endo Rectal Coil ( DATA of Dr. Lance Mynders, MAYO Clinic)

  • Dynamic Contrast Enhanced (DCE) MRI involves a series of rapid MRI scans in the presence of a contrast agent. In the case of scanning the prostate, the most commonly used material is gadolinium [4].

Axial MRI  Lava DCE with Endo Rectal ( DATA of Dr. Lance Mynders, MAYO Clinic)

  • Diffusion weighted (DW) imaging: Provides an image intensity that is related to the microscopic motion of water molecules [5].

DW image of the left parietal glioblastoma multiforme (WHO grade IV) in a 59-year-old woman, Al-Okaili R N et al. Radiographics 2006;26:S173-S189

  • Multifunctional MRI: MRI image overlaid with combined information from T2-weighted scans, dynamic contrast-enhancement (DCE), and diffusion weighting (DW) [5].

Source AJR: http://www.ajronline.org/content/196/6/W715/F3

  • Blood oxygen level-dependent (BOLD) MRI: Assessing tissue oxygenation. Tumors are characterized by a higher density of micro blood vessels. The images that are acquired follow changes in the concentration of paramagnetic deoxyhaemoglobin [5].

In the last couple of years, medical opinion leaders are offering to use MRI to solve almost every weakness of the cancer patients’ pathway. Such proposals are not always supported by any evidence of feasibility. For example, a couple of weeks ago, the British Medical Journal published a study [1] concluding that women carrying a mutation in the BRCA1 or BRCA2 genes who have undergone a mammogram or chest x-ray before the age of 30 are more likely to develop breast cancer than those who carry the gene mutation but who have not been exposed to mammography. What is published over the internet and media to patients and lay medical practitioners is: “The results of this study support the use of non-ionising radiation imaging techniques (such as magnetic resonance imaging) as the main tool for surveillance in young women with BRCA1/2 mutations.”.

Why is ultrasound not mentioned as a potential “non-ionising radiation imaging technique”?

Another illustration is the following advert:

An MRI scan takes between 30 to 45 minutes to perform (not including the time of waiting for the interpretation by the radiologist). It requires the support of around 4 well-trained team members. It costs between $400 and $3500 (depending on the scan).

The important question, therefore, is: Are there, in the USA, enough MRI  systems to meet the demand of 40 million scans a year addressing women with radiographically dense  breasts? Toda there are approximately 10,000 MRI systems in the USA. Only a small percentage (~2%) of the examinations are related to breast cancer. A

A rough calculation reveals that around 10000 additional MRI centers would need to be financed and operated to meet that demand alone.

References

  1. Exposure to diagnostic radiation and risk of breast cancer among carriers of BRCA1/2 mutations: retrospective cohort study (GENE-RAD-RISK), BMJ 2012; 345 doi: 10.1136/bmj.e5660 (Published 6 September 2012), Cite this as: BMJ 2012;345:e5660 – http://www.bmj.com/content/345/bmj.e5660
  1. http://www.auntminnieeurope.com/index.aspx?sec=sup&sub=wom&pag=dis&itemId=607075
  1. Ahmed HU, Kirkham A, Arya M, Illing R, Freeman A, Allen C, Emberton M. Is it time to consider a role for MRI before prostate biopsy? Nat Rev Clin Oncol. 2009;6(4):197-206.
  1. Puech P, Potiron E, Lemaitre L, Leroy X, Haber GP, Crouzet S, Kamoi K, Villers A. Dynamic contrast-enhanced-magnetic resonance imaging evaluation of intraprostatic prostate cancer: correlation with radical prostatectomy specimens. Urology. 2009;74(5):1094-9.
  1. Advanced MR Imaging Techniques in the Diagnosis of Intraaxial Brain Tumors in Adults, Al-Okaili R N et al. Radiographics 2006;26:S173-S189 ,

http://radiographics.rsna.org/content/26/suppl_1/S173.full

  1. Ahmed HU. The Index Lesion and the Origin of Prostate Cancer. N Engl J Med. 2009 Oct; 361(17): 1704-6
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Digital Therapeutics: A threat or opportunity to pharmaceuticals


Reporter and Curator: Dr. Sudipta Saha, Ph.D.

 

Digital Therapeutics (DTx) have been defined by the Digital Therapeutics Alliance (DTA) as “delivering evidence based therapeutic interventions to patients, that are driven by software to prevent, manage or treat a medical disorder or disease”. They might come in the form of a smart phone or computer tablet app, or some form of a cloud-based service connected to a wearable device. DTx tend to fall into three groups. Firstly, developers and mental health researchers have built digital solutions which typically provide a form of software delivered Cognitive-Behaviour Therapies (CBT) that help patients change behaviours and develop coping strategies around their condition. Secondly there are the group of Digital Therapeutics which target lifestyle issues, such as diet, exercise and stress, that are associated with chronic conditions, and work by offering personalized support for goal setting and target achievement. Lastly, DTx can be designed to work in combination with existing medication or treatments, helping patients manage their therapies and focus on ensuring the therapy delivers the best outcomes possible.

 

Pharmaceutical companies are clearly trying to understand what DTx will mean for them. They want to analyze whether it will be a threat or opportunity to their business. For a long time, they have been providing additional support services to patients who take relatively expensive drugs for chronic conditions. A nurse-led service might provide visits and telephone support to diabetics for example who self-inject insulin therapies. But DTx will help broaden the scope of support services because they can be delivered cost-effectively, and importantly have the ability to capture real-world evidence on patient outcomes. They will no-longer be reserved for the most expensive drugs or therapies but could apply to a whole range of common treatments to boost their efficacy. Faced with the arrival of Digital Therapeutics either replacing drugs, or playing an important role alongside therapies, pharmaceutical firms have three options. They can either ignore DTx and focus on developing drug therapies as they have done; they can partner with a growing number of DTx companies to develop software and services complimenting their drugs; or they can start to build their own Digital Therapeutics to work with their products.

 

Digital Therapeutics will have knock-on effects in health industries, which may be as great as the introduction of therapeutic apps and services themselves. Together with connected health monitoring devices, DTx will offer a near constant stream of data about an individuals’ behavior, real world context around factors affecting their treatment in their everyday lives and emotional and physiological data such as blood pressure and blood sugar levels. Analysis of the resulting data will help create support services tailored to each patient. But who stores and analyses this data is an important question. Strong data governance will be paramount to maintaining trust, and the highly regulated pharmaceutical industry may not be best-placed to handle individual patient data. Meanwhile, the health sector (payers and healthcare providers) is becoming more focused on patient outcomes, and payment for value not volume. The future will say whether pharmaceutical firms enhance the effectiveness of drugs with DTx, or in some cases replace drugs with DTx.

 

Digital Therapeutics have the potential to change what the pharmaceutical industry sells: rather than a drug it will sell a package of drugs and digital services. But they will also alter who the industry sells to. Pharmaceutical firms have traditionally marketed drugs to doctors, pharmacists and other health professionals, based on the efficacy of a specific product. Soon it could be paid on the outcome of a bundle of digital therapies, medicines and services with a closer connection to both providers and patients. Apart from a notable few, most pharmaceutical firms have taken a cautious approach towards Digital Therapeutics. Now, it is to be observed that how the pharmaceutical companies use DTx to their benefit as well as for the benefit of the general population.

 

References:

 

https://eloqua.eyeforpharma.com/LP=23674?utm_campaign=EFP%2007MAR19%20EFP%20Database&utm_medium=email&utm_source=Eloqua&elqTrackId=73e21ae550de49ccabbf65fce72faea0&elq=818d76a54d894491b031fa8d1cc8d05c&elqaid=43259&elqat=1&elqCampaignId=24564

 

https://www.s3connectedhealth.com/resources/white-papers/digital-therapeutics-pharmas-threat-or-opportunity/

 

http://www.pharmatimes.com/web_exclusives/digital_therapeutics_will_transform_pharma_and_healthcare_industries_in_2019._heres_how._1273671

 

https://www.mckinsey.com/industries/pharmaceuticals-and-medical-products/our-insights/exploring-the-potential-of-digital-therapeutics

 

https://player.fm/series/digital-health-today-2404448/s9-081-scaling-digital-therapeutics-the-opportunities-and-challenges

 

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The Role of Advanced Imaging in Structural Heart Interventions – Watch a Video

Reporter: Aviva Lev-Ari, PhD, RN

 

 

VIDEO: The Role of Advanced Imaging in Structural Heart Interventions

Robert Quaife, M.D., director of advanced cardiac imaging,…

WATCH VIDEO

 

VIDEOS | CATH LAB NAVIGATION AIDS | JANUARY 08, 2019

VIDEO: The Role of Advanced Imaging in Structural Heart Interventions

Robert Quaife, M.D., director of advanced cardiac imaging, University of Colorado Hospital, explains why advanced imaging techniques are required to tackle complex transcatheter procedures and structural heart interventions. The University of Colorado Hospital helped develop the Philips EchoNavigator live image fusion technology, and this video offers an overview of how it came to be and where the technology is going.

Watch the related VIDEO: Evolution of Transcatheter Mitral Valve Repair at the University of Colorado, which shows exaplmes of the navigation technology is use during a MitraClip procedure.

 

Additional videos and coverage of the University of Colorado Hospital

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2019 Trends in Cardiology

Reporter: Aviva Lev-Ari, PhD, RN

 

BLOG | DAVE FORNELL, DAIC EDITORDECEMBER 11, 2018

A 40,000 Foot View of Trends in Cardiology

A 40,000 Foot View of Trends in Cardiology

 

I was recently asked about my thoughts on the big picture, over arching trends effecting cardiology. Here is the outline I gave them.

 

Cardiology Cost Drivers

Reimbursements from Centers for Medicare and Medicaid Services (CMS) and insurance providers drive trends for the adoption of new technologies. However, new technologies that can show empirical evidence for being able to improve outcomes at lower costs are being moved up for better payments. CMS and other insurers are also using a carrot and stick approach with increased use of CMS bundled payments. These give a flat fee for diagnosing and treating a heart attack or heart failure, rather than hospitals being paid for all the tests and procedures they did. This approach makes the hospitals want to find new ways to be more cost effective to increase their bottom lines to capture more of the bundled payment as revenue.

 

Heart failure makes up about a third or more of the costs to Medicare. This has caused CMS to look closely at what is driving costs, and really high readmission rates are mainly to blame. There are penalties or no reimbursements for patients who come back for repeat treatments because they were not managed properly the first time. New technologies to address heart failure and other chronic diseases are of major interest to DAIC readers. Many of these include information technology (IT) solutions, rather than treatment device technologies.

 

Other conditions like atrial fibrillation (AF) also drive up costs, so vendors are attempting to find better ways to diagnose and treat this condition. Current treatments are only effective in the first attempt in about 60 percent of patients.

 

Consolidation of Hospitals and Outside Physicians

This is a continuing trend where single hospitals or smaller hospital systems are being bought up by bigger fish to create economy of scale with larger healthcare systems. These often cover specific geographic areas and often cast a wide net to include some luminary hospitals, smaller community hospitals, immediate care centers and minute clinics inside drug partner pharmacies. Duplicate staff and services are sometimes eliminated after mergers and consolidation. Outside physicians, including cardiologists and radiologists, are also being brought into the fold as employees of the health systems, rather than the old model as outside contractors who have access to the hospital’s amenities.

 

While there is fear about consolidation, it can also offer advantages in many cases. This includes faster access to the newest technologies and devices through the system’s luminary hospitals, which can train staff at other hospitals, and more complex cases can be referred to the larger hospital. Read about this in more detail in the article “Hospital Consolidation May Increase Access to TAVR, New Cardiac Technologies.”
Trends in Cardiovascular Technologies

Any techniques and technologies that can improve outcomes, cut costs, reduce hospital length of stay or prevent readmissions can capture hospital and cardiologist attention in today’s healthcare environment. There has been a massive movement over the past two decades away from traditional open heart or vascular surgical procedures to catheter-based interventional procedures. This includes improvements in the durability and complexity of percutaneous coronary intervention (PCI), reopening chronic total occlusions (CTOs)endovascular aortic repair (EVAR), expanded interest in treating peripheral artery disease (PAD), and structural heart cases that used to be the realm of the cardiac surgeon.

 

There is a major revolution and rapid uptake in transcatheter valve technologies to replace open heart surgery. Structural heart procedures to repair or replace failing heart valves have had positive clinical trial after positive trial over the last several years. Several key cardiac surgeons in the field say catheter based interventions will likely be the way of the future and surgical case volumes will see stead declines over the next decade.

 

The Role of Information Technology and AI in Cardiology

IT solutions are now increasingly being leveraged in more sophisticated ways since most hospitals have converted to integrated electronic medical records (EMRs) over the past decade. These allow all patient and departmental data to be accessible in one location. Analytics software is now being used to mine this data to identify workflow inefficiencies and areas to cut costs or improve charge capture. Clinical decision support (CDS) software to help hospitals and doctors better meet guideline-based care in all specialties is being introduced to help clinicians make better care decisions. This includes choosing appropriate tests and procedures in an effort to reduce costs or avoid tests that will not be reimbursed.

 

Artificial intelligence (AI) will be taking over many of the manual tasks for monitoring data and to answer questions more quickly. AI will also be used to alert administrators or doctors when it autonomously identifies a problem. Applications to watch also include AI to monitor population health in the background. This can identify patients at risk for various cardiovascular diseases before they present with any symptoms. The software also can identify patients who need extra care and counseling because of the high likelihood they will not be compliant with discharge orders and be readmitted. AI also will offer a second set of eyes on cardiac imaging to help identify anomalies or greatly reduce time by performing all the measurements automatically without human intervention.

 

This use of IT also includes patient portals to engage with patients and allow better access to their records and care. This is already starting to filter down to apps on smart phones to improve care, compliance with doctor’s orders and to aid diagnosis of conditions before they become problematic, such as heart failure and AF.

 

Cardiac Imaging Trends

Cardiac ultrasound (echo) remains the No.1 imaging modality in cardiology because of its broad availability, low cost and no radiation. However, computed tomography (CT) is poised to become the front-line imaging test for acute chest pain patients in the emergency department. It is also the gold standard for structural heart procedure planning, and the number of these cases is rapidly rising. CT fractional flow reserve (CT-FFR) technology is widely expected to become the main test for chest pain in the next decade, since it has the potential to save both time and money. CT-FFR also will become the primary gate-keeper to the cath lab to significantly lower, or possibly eliminate, the need for diagnostic catheter angiograms.

 

Cardiac MRI has seen numerous advances in recent years that cut imaging times by 50 percent and automate quantification, cutting the time to read and process these exams. MRI is expected to see and increase for cardiac exams in the coming years. MRI and CT-FFR may greatly reduce the number of nuclear exams, which are currently the gold standard for cardiac perfusion imaging.

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Reporter and Curator: Dr. Sudipta Saha, Ph.D.

 

MRI-guided focused ultrasound (MRgFUS) surgery is a noninvasive thermal ablation method that uses magnetic resonance imaging (MRI) for target definition, treatment planning, and closed-loop control of energy deposition. Ultrasound is a form of energy that can pass through skin, muscle, fat and other soft tissue so no incisions or inserted probes are needed. High intensity focused ultrasound (HIFU) pinpoints a small target and provides a therapeutic effect by raising the temperature high enough to destroy the target with no damage to surrounding tissue. Integrating FUS and MRI as a therapy delivery system allows physicians to localize, target, and monitor in real time, and thus to ablate targeted tissue without damaging normal structures. This precision makes MRgFUS an attractive alternative to surgical resection or radiation therapy of benign and malignant tumors.

 

Hypothalamic hamartoma is a rare, benign (non-cancerous) brain tumor that can cause different types of seizures, cognitive problems or other symptoms. While the exact number of people with hypothalamic hamartomas is not known, it is estimated to occur in 1 out of 200,000 children and teenagers worldwide. In one such case at Nicklaus Children’s Brain Institute, USA the patient was able to return home the following day after FUS, resume normal regular activities and remained seizure free. Patients undergoing standard brain surgery to remove similar tumors are typically hospitalized for several days, require sutures, and are at risk of bleeding and infections.

 

MRgFUS is already approved for the treatment of uterine fibroids. It is in ongoing clinical trials for the treatment of breast, liver, prostate, and brain cancer and for the palliation of pain in bone metastasis. In addition to thermal ablation, FUS, with or without the use of microbubbles, can temporarily change vascular or cell membrane permeability and release or activate various compounds for targeted drug delivery or gene therapy. A disruptive technology, MRgFUS provides new therapeutic approaches and may cause major changes in patient management and several medical disciplines.

 

References:

 

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4005559/

 

https://www.mayoclinic.org/tests-procedures/focused-ultrasound-surgery/about/pac-20384707

 

https://www.mdtmag.com/news/2017/04/nicklaus-childrens-hospital-performs-worlds-first-focused-ultrasound-surgery-hypothalamic-hamartoma?et_cid=5922034&et_rid=765461457&location=top&et_cid=5922034&et_rid=765461457&linkid=https%3a%2f%2fwww.mdtmag.com%2fnews%2f2017%2f04%2fnicklaus-childrens-hospital-performs-worlds-first-focused-ultrasound-surgery-hypothalamic-hamartoma%3fet_cid%3d5922034%26et_rid%3d%%subscriberid%%%26location%3dtop

 

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3097768/

 

https://stanfordhealthcare.org/medical-treatments/m/mr-guided-focused-ultrasound.html

 

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Comparison of four methods in diagnosing acute myocarditis: The diagnostic performance of native T1, T2, ECV to LLC

 

Reporter: Aviva Lev-Ari, PhD, RN

 

Abstract

Background:

The Lake Louise Criteria (LLC) were established in 2009 and are the recommended cardiac magnetic resonance imaging criterion for diagnosing patients with suspected myocarditis. Subsequently, newer parametric imaging techniques which can quantify T1, T2, and the extracellular volume (ECV) have been developed and may provide additional utility in the diagnosis of myocarditis. However, whether their diagnostic accuracy is superior to LLC remains unclear. In this meta-analysis, we compared the diagnostic performance of native T1, T2, ECV to LLC in diagnosing acute myocarditis.

Methods and Results:

We searched PubMed for published studies of LLC, native T1, ECV, and T2 diagnostic criteria used to diagnose acute myocarditis. Seventeen studies were included, with a total of 867 myocarditis patients and 441 control subjects. Pooled sensitivity, specificity, and diagnostic odds ratio of all diagnostic tests were assessed by bivariate analysis. LLC had a pooled sensitivity of 74%, specificity of 86%, and diagnostic odds ratio of 17.7. Native T1 had a significantly higher sensitivity than LLC (85% versus 74%, P=0.025). Otherwise, there was no significant difference in sensitivity, specificity, and diagnostic odds ratio when comparing LLC to native T1, T2, or ECV.

Conclusions:

Native T1, T2, and ECV mapping provide comparable diagnostic performance to LLC. Although only native T1 had significantly better sensitivity than LLC, each technique offers distinct advantages for evaluating and characterizing myocarditis when compared with the LLC.

SOURCE

https://www.ahajournals.org/doi/10.1161/CIRCIMAGING.118.007598

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Stanford University researchers have developed a scanner that unites optical, radioluminescence, and photoacoustic imaging to evaluate for Thin-Cap Fibro Atheroma (TCFA)

Reporter: Aviva Lev-Ari, RN

 

Early diagnosis and treatment could save lives by preventing the progression, and subsequent rupture, of these plaques. That is precisely why researchers designed the Circumferential-Intravascular-Radioluminescence-Photoacoustic-Imaging (CIRPI) system, which allows not just high-acuity optical imaging via beta-sensitive probe, but also radioluminescent marking inside the artery to determine the extent of inflammation. Photoacoustic imaging also provides information about the often-complex biological makeup of the plaques (how much is calcified or comprised of cholesterol or triglycerides).

SOURCE

https://www.mdtmag.com/news/2017/06/pet-imaging-atherosclerosis-reveals-risk-plaque-rupture?cmpid=horizontalcontent

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