Navigation Links
Noninvasive screening test may detect narrowing in intracranial stents
Date:2/11/2009

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.


'/>"/>

Contact: Kim Waterman
Kimberly_Waterman@rush.edu
312-942-7820
Rush University Medical Center
Source:Eurekalert

Related medicine news :

1. Noninvasive tests for cirrhosis may help to avoid liver biopsy
2. Breaking Study: Masimo Pleth Variability Index (PVI) Shown Effective in Noninvasive Detection of Changes in Ventricular Preload and Fluid Volume
3. Noninvasive ways to assess liver disease
4. Noninvasive Procedures Show Promise for Esophageal Bleeding
5. Masimo Receives FDA Clearance for Noninvasive Total Hemoglobin
6. PET/CT scan could be valuable noninvasive tool for determining stages of ovarian cancer
7. U.S. Air Force Awards Noninvasive Medical Technologies $2.4 Million Contract
8. FDA Approves New Roche West Nile Virus Blood Screening Test
9. New lung cancer guidelines oppose general CT screening
10. New Lung Cancer Guidelines Oppose General CT Screening
11. Lung Cancer Alliance Stands Behind CT Screening for Lung Cancer
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:6/26/2016)... Battle Creek, Michigan (PRWEB) , ... June 26, 2016 , ... ... abuse, joined as sponsor of the 2016 Cereal Festival and World’s Longest Breakfast Table ... held in honor of the city’s history as home to some of the world’s ...
(Date:6/26/2016)... ... June 26, 2016 , ... PawPaws brand pet supplements ... was developed to enhance the health of felines. The formula is all-natural and is ... herbs in the PawPaws Cat Kidney Support Supplement Soft Chews are Astragalus ...
(Date:6/26/2016)... Birmingham, Lake Orion, Clarkston, Michigan (PRWEB) , ... ... ... their direction with respect to fertility once they have been diagnosed with endometriosis. ... for tolerable intercourse but they also require a comprehensive approach that can help ...
(Date:6/25/2016)... ... June 25, 2016 , ... Austin residents seeking Mohs surgery services, ... Mohs Surgery and to Dr. Russell Peckham for medical and surgical dermatology. , Dr. ... skin cancer. The selective fellowship in Mohs Micrographic Surgery completed by Dr. Dorsey was ...
(Date:6/25/2016)... ... June 25, 2016 , ... "With 30 hand-drawn hand gesture ... said Christina Austin - CEO of Pixel Film Studios. , ProHand Cartoon’s package ... Final Cut Pro X . Simply select a ProHand generator and drag it ...
Breaking Medicine News(10 mins):
(Date:6/24/2016)... June 24, 2016  Collagen Matrix, Inc., ("Collagen ... and manufacturing of collagen and mineral based medical ... that Bill Messer has joined the ... further leverage the growing portfolio of oral surgery, ... Bill joins the Collagen Matrix executive team ...
(Date:6/24/2016)... June 24, 2016 Research ... "Structural Electronics 2015-2025: Applications, Technologies, Forecasts" ... In-Mold Electronics, Smart Skin, Structural Health ... Structural electronics involves electronic and/or electrical ... structures, replacing dumb structures such as vehicle bodies ...
(Date:6/24/2016)... Research and Markets has announced the addition of the ... to their offering. ... World Market for Companion Diagnostics covers the world market for ... report includes the following: , World IVD ... (N. America, EU, ROW), 2015-2020 , World IVD Companion ...
Breaking Medicine Technology: