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August 5, 2011

ARDMS Updates and Headlines in the News:

ARDMS: Important Testing Center Update

Treating Tremors with an Ultrasound

Predicting Perilous Plaque in Coronary Arteries via Fluid Dynamics

Feasibility Study Reports Use of a Tumor Maker and Targeted Endoscopic Ultrasound For Early Detection of Pancreatic Cancer

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ARDMS: Important Testing Center Update

Important Testing Center Update: Due to heightened security measures for admission to the test centers, previously accepted forms of ID will not be accepted if the name on the ID does not exactly match the name on your ARDMS examination-confirmation letter.  If the names are different in any way (including a middle initial that appears on the ID but not in your record or vice versa) on either form of identification, you must update your name of record with ARDMS immediately. Failure to present two forms of identification that exactly match the name reflected on your Examination Confirmation Letter will result in you being turned away from the test center and being marked absent for the appointment. Should this occur, you will be required to submit a new online application form and testing fee in order to obtain a new eligibility period within which to examine.

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Treating Tremors with an Ultrasound

Millions of Americans suffer from tremors. Patients with constant shaking can have trouble with some of life's everyday activities. Things like eating and drinking or holding a pen to write, are almost impossible. Now, learn about a breakthrough procedure that could help some patients get a steady hand.

"My hand shook constantly, as it's shaking now, it would never stop," Billy Williams, a tremor patient told Ivanhoe.

For the past 10 years, Billy Williams suffered from a tremor in his hand.

"Constantly, it never, never quit," Williams said.

No one knows why he shakes, but the tremor was so bad, Billy stopped eating out in public and his writing became illegible.

"I had trouble writing my name, I couldn't sign anything," Williams explained.

Now, neurosurgeons are using a new procedure called MRI guided focused ultrasound that stops some types of tremors.

"It involves high resolution MRI scanning as well as ultrasound technology," Jeff Elias, M.D., neurosurgeon at the University of Virginia Medical Center told Ivanhoe.

Other procedures involve invasive brain surgery, but the new scalpel-free surgery is the first to use ultrasound in the brain to treat tremors.

"We really have to be precise to within a millimeter to stop the tremor," Dr. Elias said.

The procedure is done in an MRI scanner that allows doctors to aim pulses of harmless ultrasound waves through a patient's skull to a targeted region within the brain known to be effective for treating some types of tremors. Thousands of ultrasound waves converge, heating up the area being treated, so that tremor-causing cells die.

"One of the real advantages of this technology is that it allows us the opportunity to test the patient during the treatment," Dr. Elias explained.

Billy and his doctors watched his tremor get better, and better during treatment. The end result?

"Almost immediately after the procedure my hand was as it is right now," Williams said.

It's an immediate fix to help get patient's back to a steady, normal life. Magnetic resonance guided focused ultrasound is currently in clinical trials at the University of Virginia Medical Center to treat patients with essential tremor – or ET, a progressive neurologic movement disorder. In the future, researchers plan to investigate the use of MRI guided focused ultrasound to treat other tremor disorders like Parkinson's, epilepsy and stroke.

View the article online.

Article written by staff at ivanhoe.com, and adapted for the purposes of this newsletter.

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Predicting Perilous Plaque in Coronary Arteries via Fluid Dynamics

Researchers at Emory and Georgia Tech have developed a method for predicting which areas of the coronary arteries will develop more atherosclerotic plaque over time, based on intracoronary ultrasound and blood flow measurements.

The method could help doctors identify "vulnerable plaque," unstable plaque that is likely to cause a heart attack or stroke. It involves calculating shear stress, or how hard the blood tugs on the walls of the arteries, based on the geometry of the arteries and how fast the blood is moving.

The results were posted online in the journal Circulation, published by the American Heart Association. The lead author is Habib Samady, MD, professor of medicine and director of interventional cardiology at Emory University School of Medicine.

Most people who have heart attacks do not have plaques in their arteries that bulge out and obstruct blood flow beforehand. Instead, the plaques in their arteries crack and spill open, leading to a clot. Samady says his team's ultimate aim is to try to figure out where that will happen.

Cardiology researchers studying arteries in isolation or in animals have long seen a link between branches in the arteries, disturbances in blood flow, and where atherosclerosis develops. The challenge was to translate observations from the laboratory to imaging the heart within a live person, he says.

"It's like looking at a river and predicting where sediment will accumulate," he said. "It sounds obvious, but it's hard to do it for every nook and cranny in the coronary arteries."

The Emory/Georgia Tech study was the largest published investigation of shear stress and plaque progression in humans so far, and the first to examine people with significant coronary artery disease. Doctors examined 20 patients in Emory University Hospital's catheterization laboratory between December 2007 and January 2009. They were being examined because they had abnormal exercise EKGs or stable chest pain. The patients' coronary arteries were examined by intracoronary ultrasound and Doppler guide wire before and after six months of therapy with atorvastatin (Lipitor).

To model shear stress, Samady, assistant professor Michael McDaniel, MD, and postdoctoral fellow Parham Eshtehardi, MD, teamed up with Jin Suo and Don Giddens, experts in fluid mechanics at Georgia Tech. The patients' arteries were divided into more than 100 segments each, and the shear stress was calculated for each one. Ultrasound allowed the researchers to estimate the size and composition of the plaques in each segment before and after the six month period.

"Some atherosclerotic plaque appears to develop in a steady progression, and in other places, it develops in fits and spurts. These areas exist within the same patient and the same artery," Samady said. "Our thinking is that the places where plaque develops in more fits and spurts may lead to the rupture of plaque, leading to a clot that blocks blood flow. In contrast, the places where you have steady progression may be more stable, as long as there is a fibrous covering that is thick enough."

Analyzing each segment, the overall area of the plaque increased and the core of the plaque grew larger in places where shear stress was especially low. In places where the shear stress was high, there was shrinking of the fibrous covering of the plaque and expansion of lipid necrotic core and dense calcified areas.

"High shear stress leads to regression, which you might think is good, but there are some bad actors that may lead to plaque rupture," he said. "What's new here is that we're seeing the detrimental effects of both low and high shear stress."

The data also shows that arterial plaques can grow despite anti-cholesterol therapy with statins, the current standard of care. To really gauge whether plaque in a certain spot is going to be dangerous, Samady says doctors would need to look at outcomes in more patients over a longer time frame.

"The dream is to predict which spot is vulnerable, and use that to guide treatment with drugs and interventions like stents," he said. For the present, the shear stress-based method can be used to monitor patients' progress and determine how well treatment is working. Samady said "Ultrasound and blood flow measurements could be combined with a newer technique called optical coherence tomography for better resolution and more information".

View the article online.

Article written by staff at sciencedaily.com and adapted for the purposes of this newsletter.

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Feasibility Study Reports Use of a Tumor Maker and Targeted Endoscopic Ultrasound for Early Detection of Pancreatic Cancer

Researchers from New England report in a new study that using a tumor marker, serum CA 19-9, combined with an endoscopic ultrasound if the tumor marker is elevated, is more likely to detect stage 1 pancreatic cancer in a high-risk population than by using the standard means of detection. The study appears in the July issue of GIE: Gastrointestinal Endoscopy, the monthly peer-reviewed scientific journal of the American Society for Gastrointestinal Endoscopy (ASGE).

Pancreatic cancer is the fourth leading cause of cancer death in the United States. Advanced disease at diagnosis correlates directly with worse overall survival. Symptoms of abdominal pain, jaundice, and/or weight loss often do not appear until the tumor is locally advanced or metastatic, at which point effective treatment options are very limited. By contrast, detection and resection of pancreatic cancer, when it is confined to the pancreas (stage 1 disease), improves overall survival. An effective screening protocol is urgently needed to detect earlier stage tumors. Imaging methods that have been used for pancreatic cancer screening include endoscopic ultrasound (EUS), CT, endoscopic retrograde cholangiopancreatography (ERCP) and magnetic resonance imaging/MRCP.

There has been limited success in screening younger populations using the tumor marker CA19-9, so more recent pancreatic cancer screening protocols have focused on high-risk populations. It is estimated that 10 percent of patients in whom pancreatic cancer develops have at least one first-degree relative with the disease. Multiple cohort and case-control studies have demonstrated that a family history of a first-degree relative with pancreatic cancer significantly increases a patient's risk of the development of pancreatic cancer, approximately two to five-fold. The risk of the development of pancreatic cancer increases significantly as the number of affected family members increases. Advanced age is also a significant risk factor, and 93 percent of patients with pancreatic cancer present after the age of 50.

"Our hypothesis was that a high-risk population identified by age and at least one first-degree relative with pancreatic cancer can be successfully screened. Our objective was to determine whether early pancreatic neoplasia can be detected in a high-risk population by using tumor marker CA 19-9 followed by targeted endoscopic ultrasound. We also sought to determine whether this protocol was more likely to detect early stage pancreatic cancer than standard means of detection," said study lead author Richard Zubarik, MD, Fletcher Allen Health Care, University of Vermont. "Our results showed that potentially curative pancreatic adenocarcinoma can be identified with this screening protocol. Stage 1 pancreatic cancer is more likely to be detected by using this screening protocol than by using standard means of detection."

Methods

This prospective cohort study was conducted at the University of Vermont (UVM) and the Dartmouth-Hitchcock Medical Center (DHMC). Patients were enrolled from September 2006 to July 2009. Patients included were between the ages of 50 and 80 and had at least one first-degree relative (parent, sibling, or child) with pancreatic cancer. Enrollment was initiated at age 45 if a patient had two first-degree relatives with pancreatic cancer and at age 40 if the person had a BRCA2 mutation or Peutz-Jeghers syndrome.

Serum CA 19-9 testing was performed on all patients. It was chosen as the initial screening method because it is acceptable to patients, easily obtainable, widely available, inexpensive, and relatively sensitive for the disease. Endoscopic ultrasound was performed only in patients with an elevated CA 19-9 level (a CA 19-9 value greater than 37 U/mL was considered elevated) regardless of whether only one or more than one family member was affected with pancreatic cancer.

Patients who were diagnosed with pancreatic cancer at UVM (but were not enrolled in the CA 19-9/EUS study) during the same period were prospectively identified and used as the comparison group. These patients were identified by the Cancer Data Registry at the University of Vermont. Charts were then reviewed to verify tumor type, staging data and survival.

Results

A total of 546 patients were enrolled in the study. CA 19-9 was elevated in 27 patients (4.9 percent). Neoplastic or malignant findings were detected in five patients (0.9 percent), and pancreatic cancer in one patient (0.2 percent). The patient with pancreatic cancer detected as part of this study was one of two patients presenting to the University of Vermont with stage 1 cancer. One-year follow-up contact was performed by telephone in 519 patients (95 percent), by chart review in 24 patients (four percent), and by review of the social security death index in three patients (less than one percent). Pancreatic cancer was not detected at the one-year follow-up in any additional patients.

In the comparison group, a total of 124 patients received a diagnosis of pancreatic cancer between September 2006 and July 2009. Staging of the comparison group at the time of presentation was as follows: stage 1, one patient (0.9 percent); stage 2, 52 patients (45.6 percent); stage 3, 20 patients (17.5 percent); stage 4, 41 patients (36 percent). The patient detected in the CA 19-9/EUS study had stage 1 disease, whereas only 0.9 percent of patients in the comparison group presented with stage 1 disease. This difference was statistically significant despite only having one patient with pancreatic cancer detected in the study group because the detection of stage 1 cancer in the comparison group was so rare. Median survival for the 122 subjects in the comparison group was seven months, with a 2-year survival rate of 10 percent.

The results conclude that potentially curative pancreatic cancer can be identified with CA 19-9 and targeted EUS. Stage 1 pancreatic cancer is more likely to be detected by using this screening protocol than by using standard means of detection. Potential advantages include acceptable rates of disease diagnosis and exclusion as well as acceptable costs (cost to detect 1 pancreatic neoplasia was $8,431, while the cost to detect 1 pancreatic cancer was $41,133). In particular, the patient with pancreatic cancer detected with this screening protocol is alive without evidence of recurrence three years after surgical resection and is the longest survivor of pancreatic cancer detected in a published screening protocol. Also, evidence of pancreatic cancer did not develop in subjects with negative screening studies, at least in short-term follow-up.

The researchers note that the sample size is adequate only to demonstrate the feasibility of this approach, but summarized that this trial successfully screened a high-risk patient population for pancreatic cancer based on age and genetic predisposition. Early pancreatic cancer, associated with prolonged disease-free survival, can be detected as part of this pancreatic screening protocol. Stage 1 pancreatic cancer was more likely to be detected with CA 19-9 and targeted EUS, and it appears to be superior to the standard means of pancreatic cancer detection.
View the article online.

Article written by staff at medicalnewstoday.com and adapted for the purposes of this newsletter.

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