RSS Feeds

Earth Science

Space Science

Life Science

Fields of Scientific Study

Nanotechnology

Cancer

Definitions of The Fields of Scientific Study

Noninvasive Screening Test May Detect Narrowing in Intracranial Stents According to Study by Rush University Medical Center

February 12, 2009

Great advances have been made in treating blockages in the arteries of the brain using angioplasty to widen the narrowed artery and a stent to hold the artery open. However, in-stent stenosis, or a re-blockage of the artery within the stent due to scar tissue or blood clots, is estimated to occur in up to 30 percent of patients and can cause a stroke or death.

A new study by researchers at Rush University Medical Center has found that quantitative magnetic resonance angiography (QMRA) is a promising screening tool to detect in-stent stenosis with high sensitivity and specificity. The study is available early online and will appear in the March issue of Stroke: Journal of the American Heart Association.

Noninvasive imaging such as magnetic resonance angiography (MRA) and computerized tomography angiography often can not provide an accurate diagnosis of in-stent stenosis because the image is distorted by the reflection of metal stents or coils. Due to this problem, conventional angiography continues to be used routinely after stent placement to screen for in-stent stenosis. However, conventional angiography requires threading a catheter from the arteries in the groin to the brain and carries a slight risk of neurological and non-neurological procedural complications.

Quantitative MRA (QMRA) is a flow analysis system that uses traditional MRI to produce a 3D model of the vasculature and quantify vessel blood flow. The procedure is completely non-invasive and no contrast is needed. Recent studies have established this technology's use in the measurement of arterial blood flow in various cerebrovascular conditions and carotid bypass surgery; however, this is the first study to assess the use of QMRA in the detection of intracranial in-stent stenosis.

The study authors conducted a retrospective review of 14 patients who underwent stent placement for cerebral aneurysm or intracranial stenosis. All patients had a QMRA scan performed within one year after stent placement and a follow-up diagnostic angiography study performed within one month of the QMRA scan. An interventional neurologist reviewed all angiograms for presence of greater than 50 percent in-stent stenosis.

The study found that low blood flow as measured by QMRA at sites of intracranial stent placement was significantly associated with in-stent stenosis by catheter-based angiography. As a screening tool to predict greater than 50 percent in-stent stenosis, QMRA was 100% sensitive. In other words, QMRA was able to detect narrowing of stented arteries in all cases where invasive angiography showed greater than 50 percent stenosis.

"Given the potentially deadly consequences of in-stent stenosis, a test with high sensitivity and an acceptably low false-positive rate is desirable," said Dr. Shyam Prabhakaran, section head of Cerebrovascular Disease and Neurological Critical Care at Rush. "In addition, none of the patients with normal QMRA results had stenosis on angiography, suggesting that patients with normal QMRA results may not require follow-up catheter-based angiography."

Due to the small sample size of the study, the authors suggest larger prospective studies to confirm their findings.

Rush University Medical Center is certified by the Joint Commission as Primary Stroke Center. The Comprehensive Stroke Program at Rush includes a multi-disciplinary team of neurologists, cerebrovascular neurosurgeons, neuro-radiologists, stroke-trained nurses, rehabilitation services, and physical therapists. Rush is ranked 15th in the nation in neurology and neurosurgery, according to 2008 U.S. News and World Report "America's Best Hospitals" rankings.

Rush University Medical Center

Related Stenosis Current Events and Stenosis News Articles

Stenosis Current Events and Stenosis News RSS

Higher carotid arterial stenting rates associated with poorer clinical outcomes
Among eligible Medicare beneficiaries, increased use of carotid arterial stenting (CAS) procedures to treat carotid stenosis-the narrowing of the carotid artery-is associated with higher rates of mortality and adverse clinical outcomes, including heart attack and stroke, according to researchers from the University of Pennsylvania School of Medicine.

Study questions need for routine intervention in patients with renovascular disease
Some invasive procedures that are becoming increasingly common as a first line of treatment for patients diagnosed with narrowed arteries in and around the kidneys may not be necessary.

Few complications 1 year after aortic valve implantation
Research presented at the 21st annual Transcatheter Cardiovascular Therapeutics (TCT) scientific symposium, sponsored by the Cardiovascular Research Foundation (CRF), demonstrated an "exceptionally low" rate of complications one year after implantation of transcatheter aortic valve prostheses.

Comprehensive cardiac CT scan may give clearer picture of significant heart disease
A team of researchers led by Massachusetts General Hospital (MGH) radiologists has developed a computed-tomography-based protocol that identifies both narrowing of coronary arteries and areas of myocardial ischemia - restricted blood flow to heart muscle tissue - giving a better indication of clinically significant coronary artery disease.

Study finds women slightly more likely to die than men in the 30 days following a heart attack
A new study from NYU School of Medicine found that women may have a slightly higher risk of death than men in the thirty days following an acute coronary syndrome (ACS), but that these differences appear to be attributable to factors such as severity and type of ACS.

Back to normal: Surgery improves outcomes for spine patients
People with the spine disease called degenerative spondylolisthesis -- who choose surgical treatment -- experience substantially greater relief from pain over time compared to those who do not have surgery.

Combination of aspirin and an anti-clotting drug reduces risk of dialysis access failure
For the first time, a combination of aspirin and the anti-platelet drug dipyridamole has been shown to significantly reduce blockages and extend the useful life of new artery-vein access grafts used for hemodialysis, according to a study by the Dialysis Access Consortium (DAC).

Combination of ASA and clopidogrel reduces heart attack risk in patients with acute coronary syndrome
In order to better prevent blood clots, clopidogrel can be prescribed to patients with acute ischaemia of the heart muscle, in addition to acetylsalicylic acid (ASA). The Institute for Quality and Efficiency in Health Care (IQWiG) has now investigated whether the combination of clopidogrel and ASA actually has a higher benefit for patients than ASA alone.

Valve implantation on the beating heart
Transcatheter valve implantation is a newly developed technique for the curative treatment of high-grade aortic stenosis. It is likely to be of benefit especially to elderly, multimorbid patients for whom the risk of open heart surgery would be too great.

Radiologists Can Dramatically Lower Cardiac CT Radiation Dose in Some Patients
Radiologists can now lower the radiation dose delivered by cardiac CT angiography by 39% in adult patients weighing 185 pounds or less, according to a study performed at the University of Erlangen in Erlangen, Germany.

More Stenosis Current Events and Stenosis News Articles

	The Official Patient's Sourcebook on Spinal Stenosis by James N. Parker (Editor), Philip M. Parker (Editor) This book has been created for patients who have decided to make education and research an integral part of the treatment process. Although it also gives information useful to doctors, caregivers and other health professionals, it tells patients where and how to look for information covering virtually all topics related to spinal stenosis (also Cervical Spinal Stenosis; Degenerative Lumbar Spinal Stenosis; Familial Lumbar Stenosis; Lumbar Canal Stenosis; Lumbar Spinal Stenosis; Lumbosacral Spinal Stenosis), from the essentials to the most advanced areas of research. The title of this book includes the word official. This reflects the fact that the sourcebook draws from public, academic, government, and peer-reviewed research. Selected readings from various agencies are reproduced to give...
	Conquer Back and Neck Pain: Walk It Off! A Spine Doctor'sProven Solutions For Finding Relief Without Pills or Surgery by Mark Brown (Author) Every human being suffers from back pain at some point in life. In an effort to find relief, people turn to a wide variety of treatments, and to doctors who will prescribe narcotic painkillers. What they don t realize is that many of these treatments -- especially narcotic drugs -- actually interfere with their body s own ability to heal and overcome pain. When these treatments fail to help, they desperately conclude that surgery is their only option for relief. In his new book Conquer Back and Neck Pain: Walk It Off!, renowned spine surgeon Dr. Mark Brown, MD, PhD, explains exactly what causes back pain and why humans are so predisposed to spinal problems. He provides a detailed questionnaire that allows you to identify which of seven types of back pain you are experiencing, and then...
	Low Back Pain (Medical Student Coach) by Medical Student Coach Low back pain is a common presentation of patients to the Internal Medicine clinic, Emergency Department, and other types of clinics. In preparation for the USMLE Step 1, USMLE Step 2 CK, USMLE Step 2 CS, and USMLE Step 3, medical students need to know the differential diagnosis, history and physical, assessment, and treatment for this common chief complaint. The Medical Student Coach series is here to help you tackle this. If you are a patient, this will give you great insight into what your doctors are thinking and the empowerment you need to ask questions. This book covers low back pain, lumbar pain, sacral pain, nerve root compression, nerve root disease, radiculopathy, cauda equina syndrome, spondylosis, disk herniation, spinal stenosis, spondylolisthesis , etc.
	Cardiac Cath, 90% Stenosis Main Coronary Artery Photographic Poster Print, 40x30 by Art.com Art.com is the world's largest retailer of art prints, posters, photographs, and framed artwork. With our huge selection of over 400,000 prints, you'll easily find the perfect piece for your home, office, or classroom. Our art is printed on quality paper. When you order framed artwork, the piece is built by our team of in-house professionals. Visit our Amazon store today at www.amazon.com/artdotcom to find Special Offers and search for products based on 'Artist Name' and 'Subject Categories' such as Movie, Music, Vintage, TV, Children, Travel, Kitchen, Museum Art, Animals, Floral, Motivational, and Sports. Art.com is dedicated to providing you with high quality products and service by offering you 100% satisfaction guaranteed. We ship internationally to over 80 countries. Decorate your...
	Lumbar Spinal Stenosis by Marek Szpalski (Editor), Robert Gunzburg (Editor) Centenary Clinic, Antwerp, Belgium. Comprehensive and illustrated text presenting basic sciences, clinical presentation, physiopathology, and diagnosis, to conservative and surgical treatment modalities. Also discusses economic and ethical considerations and management of LSS. For clinicians, researchers, and manipulation therapists. DNLM: Spinal Stenosis--diagnosis.
	Drug-eluting Stents: Are they Safe? Drug-eluting stents are metal mesh tubes coated with medication that keep arteries from re-blocking after angioplasty. These devices have been the solution for millions of people around the world. However, recent studies have raised concerns about associated risks. Join Dr. Yeung and colleagues as they discuss the safety of these popular devices This product is manufactured on demand using DVD-R recordable media. Amazon.com's standard return policy will apply.
	Modern Diagnostic and Surgical Therapy of Recurrent Urethral Stenosis [VHS] Starring: Walter Merkle
	Digital Svelte Surpass Sauna Belt by Svelte The Svelte Surpass Sauna Belt ANP56G is our top-of-the-line belt, featuring low-voltage operation and digital temperature and time controls (up to 95 minutes). At 52 inches (end to end) it is also the longest of our belts, with a continuous 9-inch width. Low-voltage operation means the greatest efficiency in producing Far Infrared Radiant heat, and it is safe even from accidental contact with fingernails or water. Like our other highest quality products, the Svelte Surpass Sauna Belt ANP56G has solid, one-piece construction, of nylon and space carbon fiber. Its size ensures ample coverage and a comfortable fit for any wearer. The improved digital controls are operated by a microprocessor, housed in a sturdy, stand-alone control box.
	MAGNETIC THERAPY Power Pad for BACK PAIN RELIEF by Magnetic Products International Our Magnetic Therapy, for daytime and nighttime PAIN RELIEF has been Medically test proven, at major Medical Centers, to effectively increase blood circulation and provide outstanding pain relief These therapeutic magnets reduce swelling and pain, expediting the healing process for chronic and acute conditions. Our magnetic therapy provides excellent results whether the conditions are acute or chronic.
	Lumbar Spinal Stenosis by Gunnar B. J. Andersson (Author), Thomas W. McNeill (Author) Written by internationally renowned experts in orthopaedics, neurosurgery, anatomy and neuroradiology, this book presents a comprehensive approach to the etiology, diagnosis and treatment of stenosis of the lumbar spine - a condition that is seen in most humans by the age of 70 or before. Organized into five sections, this multi-contributed book covers the basic science, pathology, diagnosis, non-operative treatment, operative treatment, and post-operative management of stenosis of the lumbar spine. It is comprehensive in its coverage and provides many answers to the major problems in the treatment of spinal stenosis of how to decompress adequately and still maintain stability.