Posts Tagged ‘X-ray’

North Star Imaging and Instron is in Southern California for Helping the Industry, Academia, and Research

Reporter: Danut Dragoi, PhD

Today I visited North Star Imaging and Instron companies for their Open House in Irvine, California. I believe this is the first in California. Knowing some of their products very well I realized, after professional presentations and live demos that these machines can help Californian industry, Department of Homeland Security, as well as the research in many aspects of it, from nondestructive evaluation of key industrial products, medical devices inspections, aeronautic composites, as well as new applications in actual research such as Laser Metal Printing, Mechanical Engineering, bio-implants, etc. I found very interesting the presentation on imaging a 3D Printed object with an internal complex topology. For the quality of their pictures, cross sections and resolution I congratulate the team that put these breakthroughs together. The picture below is an X5000 x-ray machine capable  of producing high quality computed tomography pictures (CT) of various objects from many domains of industry and research.


Image SOURCE: http://4nsi.com/events/open-house

The famous STL files for 3D printing are produced here in a X5000 machine. A definition of STL file is given here. The STL (STereoLithography) is a file format native to the stereolithography CAD software created by 3D Systems. STL has several after-the-fact backronyms such as “Standard Triangle Language” and “Standard Tessellation Language”. This file format is supported by many other software packages; it is widely used for rapid prototyping, 3D printing and computer-aided manufacturing. STL files describe only the surface geometry of a three-dimensional object without any representation of color, texture or other common CAD model attributes. The STL format specifies both ASCII and binary representations. Binary files are more common, since they are more compact. An STL file describes a raw unstructured triangulated surface by the unit normal and vertices (ordered by the right-hand rule) of the triangles using a three-dimensional Cartesian coordinate system. STL coordinates must be positive numbers, there is no scale information, and the units are arbitrary. Once the 3D object is scanned, the STL file can be downloaded to the 3D printer machine and a copy of the original can be produced. For people working on Medical 3D Printing this machine is extremely useful.

Before a product is tested with Instron, the 3D pictures are important to be produced. In this way a complete analysis can be done in a very convenient time-machine and time-operator way. The next Figure below shows an Instron machine taken from here 


Image SOURCE: http://www.renishaw.com/en/instron-equips-its-new-electropuls-linear-torsion-tester-with-advanced-renishaw-encoders–29004

According with the information released, link in here, Instron, headquartered in Massachusetts, USA, is a global market leader in the materials testing industry. It manufactures and services a comprehensive range of materials testing equipment and accessories for the research, industrial and academic sectors. A variety of Instron systems test samples ranging from components for jet engines to medical syringes.

Instron has just launched an advanced bi-axial variant of the ElectroPuls E3000 All-Electric test instrument. The E3000 is a compact table-top instrument comprising: a load frame, crosshead with combined linear/torsion actuator, Dynacell load cell and T-slot table for fixing samples.

The state-of-the-art ElectroPuls series includes the E1000, E3000 and E10000 fatigue test systems. These are suited for biomedical / biomechanical research applications and feature a wide dynamic performance range and low force characteristics. ElectroPuls is all-electric and utilises linear motor technology, which eliminates the need for ball / lead-screws and enables slow-speed static tests through to high-frequency dynamic tests at over 100 Hz.

The new E3000 linear-torsion is a smaller-scale equivalent of the E10000 linear-torsion system and includes a rotation axis with a standard range of ±135° as well as optional multi-turn capability for applications such as orthopaedic bone-screw testing. An ElectroPuls bi-axial linear-torsion test can be conducted on most materials and has found applications in testing inter-vertebral disc prostheses, various bio-materials, athletic footwear and elastomeric components.

The Open House of the two companies, NSI and Instron, was very well organized and it was a great success for Californian industry, Academia, Medical testing, and Research.




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Reporter: Aviva Lev-Ari, PhD, RN

CT Scanner Delivers Less Radiation

Faster, more sensitive scans and better image processing may reduce the risk of x-ray-related cancers.


A new CT scanner exposes patients to less radiation while providing doctors with clearer images to help with diagnoses, according to researchers at the National Institutes of Health.

“CT” stands for Computerized Tomography, which involves combining lots of x-ray images taken from different angles into a three-dimensional view of what’s inside the body. The technology can be especially useful for diagnoses in emergency situations, and the number of CT scans in recent years has increased dramatically, says Marcus Chen, a cardiovascular imager at the National Heart, Lung and Blood Institute, in Bethesda, Maryland.  But the increase in the use of CT scans raises concerns about the amount of radiation to which patients are exposed, says Chen.

The risk of developing cancer from the radiation delivered by one CT scan is low, but the large number of scans performed each year—more than 70 million—translates to a significant risk. Researchers at the National Cancer Institute estimated that the 72 million CT scans performed in the U.S. in 2007 could lead to 29,000 new cancers. On average, the organ studied in a CT scan of an adult receives around 15 millisieverts of radiation, compared with roughly 3.1 millisieverts of radiation exposurefrom natural sources each year.

This concern has led researchers to seek ways to reduce the amount of radiation exposure a patient receives in a scan. They are working to improve both hardware, to make the scans go faster and need less repetition, and software, to process the x-ray data better (see “Clear CT Scans with Less Radiation”).

The new CT scanning system, from Toshiba Medical, combines several improvements to reduce radiation exposure. The overall body of a CT scanner is shaped like a large ring. An x-ray tube and a detector spin separately in the ring, opposite one another, and a patient lies in the center.  X-rays travel through the patient as they are delivered by the tube and captured by the detectors. The new Toshiba machine has five times as many detectors as most machines, which means that more of an organ can be captured at a time, decreasing the number of passes of the scanner required.

The x-ray components in the new system also spin faster—it takes only 275 milliseconds for them to complete a rotation, instead of 350 millisesconds—which means a patient gets irradiated for less time. In cases where doctors are looking at a moving organ such as the heart, the faster spinning also reduces the number of times a doctor may need to try to get a good image. “It’s like having faster film in your camera,” says Chen.  Changes to the way the system generates x-rays and computes the images also mean patients spend less time getting hit with radiation.

Chen and colleagues at the National Heart Lung and Blood Institute used the Toshiba system to examine 107 adult patients of different ages and sizes for plaque buildup and cardiovascular problems. Patient size matters because more x-rays are required to image a larger person. “A lot of imaging centers will use one setting for all patients,” says Chen. “You get beautiful image quality on everybody, but the downside is that some patients get more radiation than they probably should.” In his study, the system takes a quick preliminary scan that uses low-dose x-rays to figure out how big a patient is and how much radiation will be needed for the diagnostic image.

Most patients who got a scan in the new Toshiba machine received 0.93 millisieverts of radiation, and almost every patient received less than 4 millisieverts. Radiation exposure was decreased by as much as 95 percent relative to other CT scanners currently in use.


The reader is advised to review Alternative #3 in the following article, published on 3/10/2013, including the Editorial in NEJM by Dr. Redberg, UCSF, included in the article, prior to reading the content, below — as background on this important topic having the potential to change best practice and standard of care in the ER/ED.

Acute Chest Pain/ER Admission: Three Emerging Alternatives to Angiography and PCI – Corus CAD, hs cTn, CCTA

CCTA for Chest Pain Cuts Costs, Admissions

By Eric Barnes, AuntMinnie.com staff writer

May 14, 2013 — One of the largest studies yet comparing medical resource use and outcomes among chest pain patients found that coronary CT angiography (CCTA) reduced medical resource utilization compared to standard care, generating fewer hospital admissions and shorter emergency room stays, researchers reported in the Journal of the American College of Cardiology.

The retrospective study compared matched cohorts of nearly 1,000 patients presenting with chest pain before and after implementation of routine CCTA evaluation. The study team from Stony Brook, NY, and two other institutions found that patients receiving the standard workup for chest pain — which is to say, mostly observation — were admitted to the hospital almost five times as frequently as patients receiving CT. The standard workup patients also had significantly longer stays when admitted.

The rates of invasive angiography without revascularization and recidivism were also much higher for patients receiving standard care (JACC, May 14, 2013).

“I think the take-home message is that CT done correctly by experts with the resources to do it correctly on a routine basis is not only safe and feasible, but reduces healthcare resource utilization,” said lead author Dr. Michael Poon, from Stony Brook Medical Center, in an interview with AuntMinnie.com.

More than $10 billion in costs

Caring for chest pain is an expensive proposition in the U.S., costing upward of $10 billion a year for some 6 million emergency department (ED) visits. To reduce the problem of overcrowded emergency rooms, some hospitals have implemented chest pain evaluation units, but the care isn’t comprehensive or necessarily all that helpful, Poon said.

“It has been a problem and a major dilemma for emergency rooms because for most patients, it’s a false alarm,” he said. “I would say nine out of 10 are false alarms, but how to pick out that one is very tricky and costly. So what most hospitals tend to do is a one-size-fits-all policy where everybody gets blood tests and an electrocardiogram, and they keep patients in the ED for an extended period of time. So if you come in Friday, you may stay until Monday.”

Coronary CTA has been shown to be safe and cost-effective for acute chest pain evaluation in several smaller studies and in three smaller multicenter trials, but those studies have been limited by a lack of CT availability outside of weekdays and office hours, while EDs must operate 24/7, Poon said.

“All of those studies were done in a randomized, controlled fashion and in an artificial environment,” where each patient was randomized to either a stress test or CT during weekday office hours, Poon said. “But in real life, there is no such thing; it cannot be done.”

More often, chest pain patients get a couple of tests and several hours of observation before they are sent home.

Poon and colleagues from Stony Brook, William Beaumont Hospital, and the University of Toronto wanted to do a “real-world” observational study to show that CT remained cost-effective and efficient for triaging chest pain patients.

The study sought to compare the overall impact of CT on clinical outcomes and efficacy, when comparing CCTA and the hospital’s standard evaluation for the triage of chest pain patients, with CCTA available 12 hours a day, seven days a week.

From a total of 9,308 patients with a chest pain diagnosis upon admission, the study used a matched sample of 894 patients without a history of coronary artery disease and without positive troponin or ischemic changes on an electrocardiogram.

Patients undergoing CT were scanned on a 64-detector-row scanner (LightSpeed VCT, GE Healthcare) following administration of iodinated contrast and metoprolol as a beta-blocker for those with heart rates faster than 65 beats per minute (bpm).

Those with a body mass index (BMI) less than 30 were scanned at 100 kV, while those with a BMI between 30 and 50 were scanned at 120 kV. Retrospective gating was reserved for patients whose heart rates remained above 65 bpm. Obstructive stenosis was defined as 50% or greater lumen narrowing.

CT choice faster, more efficient

The results showed a lower overall admission rate of 14% for CCTA, compared with 40% for the standard of care (p < 0.001). In fact, patients undergoing standard evaluation were 5.5 times more likely to be admitted (p < 0.001) than CCTA patients.

The length of stay in the ED was 1.6 times longer for standard care (p < 0.001) than for CCTA. For patients undergoing CCTA, the median radiation dose was 5.88 mSv.

“We also showed that the recidivism rate is higher for standard of care, meaning that they come back within one month with recurrent chest pain,” Poon said. The odds of returning to the ED within 30 days were five times greater for patients in the standard evaluation group (odds ratio, 5.06; p = 0.022).

“In the era of Obamacare, this is a penalty to the hospital; you don’t want the patient returning within one month with the same diagnosis,” he said. When that happens, “you’re not only not getting paid, you have to pay a penalty. It’s a double whammy. We also show that downstream invasive coronary angiography is significantly less in the CCTA arm.”

More invasive angiography

Patients receiving standard care were seven times more likely to undergo invasive coronary angiography without revascularization (odds ratio, 7.17; p ≤ 0.001), while neither patient group was significantly more likely to undergo revascularization.

“Many physicians use [catheterization] as a way of getting patients in and out of the hospital,” Poon said. However, the cost is more than $10,000 per procedure.

The high rate of angiography without revascularization in the standard care group was not seen in the Rule Out Myocardial Infarction/Ischemia Using Computer Assisted Tomography (ROMICAT) I and II trials, where all patients in the standard care group underwent stress testing before angiography was considered, he said.

Poon credited the ROMICAT trials’ routine use of stress tests with diminishing CT’s relative advantage in resource use. “In the real world, that is not available,” he said. The present study, in which only about 20% of the standard care patients underwent stress tests, is more realistic.

Finally, Poon and colleagues showed no difference in rates of myocardial infarction between CT and the standard of care within the first 30 days of follow up. However, that is changing as patients are followed for longer time periods, he noted.

“We see a trend starting to diverge in our next report, which follows [patients] for six months,” he said. “You see a lot more acute myocardial infarction in the standard care arm, and we’re going to extend it for a year.”

The authors concluded that using CCTA to rule out acute coronary syndromes in low-risk chest pain patients is likely to improve doctors’ ability to triage patients with the common presentation of chest pain. The result of this approach appears to be fewer hospital admissions, shorter stays, less recidivism, less invasive angiography, and better patient outcomes.

In any case, Poon said, the study method is permanent at Stony Brook University, where the standard of care now incorporates CCTA.

“We didn’t stop doing it after the study,” he said. “If you look at some of the randomized, controlled studies, they actually went back to the standard of care.” They had to because those kinds of protocols are only practical with a grant.

Related Reading

CORE 320 study evaluates CCTA and SPECT for CAD diagnosis, March 25, 2013

Study affirms CCTA’s value to rule out myocardial infarction, March 19, 2013

CCTA predicts heart attack in people without risk factors, February 19, 2013

Study: Use CCTA 1st for lower-risk chest pain patients, February 4, 2013

2010 CCTA appropriateness criteria yield mixed results, January 31, 2013
Copyright © 2013 AuntMinnie.com


Other related articles on this Open Access Online Scientific Journal include the following:

Economic Toll of Heart Failure in the US: Forecasting the Impact of Heart Failure in the United States – A Policy Statement From the American Heart Association

Aviva Lev-Ari, PhD, RN, 4/25/2013


Diagnosis of Cardiovascular Disease, Treatment and Prevention: Current & Predicted Cost of Care and the Promise of Individualized Medicine Using Clinical Decision Support Systems

Larry H Bernstein, MD, FACP and Aviva Lev-Ari, PhD, RN, Curator, 5/15/2013


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