Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

CT angiography may be unnecessary in patients with suspected pulmonary embolism

15.06.2010
A new study suggests that computed tomography (CT) angiography might be unnecessary in many patients suspected of having pulmonary embolism (PE), based on the results of risk assessment analysis. PE risk assessment could help reduce radiation exposure and costs associated with CT angiography. The results of the study appear in the online edition and August print issue of the journal Radiology.

"Our study suggests that the frequency of ordering CT angiograms can be markedly reduced with resultant cost-savings and decreased radiation exposure," said lead author Mark D. Mamlouk, M.D., radiology resident at the University of California, Irvine in Orange, Calif.

Pulmonary embolism occurs when a blood clot, usually from the leg, travels through the bloodstream and gets lodged in a pulmonary artery. The condition can be fatal, so prompt diagnosis is critical.

CT angiography's high sensitivity and specificity has made it the preferred modality for diagnosing PE. However, the increasing use of the examination has fueled concerns over procedure costs and radiation exposure to patients, along with risks associated with the use of contrast agents.

For the study, the researchers assessed the possibility of using risk factors associated with thromboembolism, or blood clot formation, to reduce the number of CT angiograms for PE. They reviewed the electronic medical records of 2,003 patients who underwent CT angiography for possible PE between July 2004 and February 2006. Among the risk factors assessed were age, history of immobilization and cancer. Other risk factors included excess estrogen state, a history of venous thromboembolism, gender and disorders that cause blood to clot more easily than normal.

Overall, CT angiograms were negative for PE in 1,806 of 2,003 patients, or 90.2 percent. Among the 197 patients with CT angiograms positive for PE, 192, or 97.5 percent, had one or more risk factors.

All of the risk factors except gender were determined to be statistically significant. Age of 65 years or older and immobilization were the most common risk factors in positive PE patients.

Of the 1,806 patients with CT angiograms negative for PE, 520 (28.8 percent) had no risk factors. Furthermore, excluding age and gender, 1,119 (62 percent) had no risk factors. Risk factor assessment had a sensitivity of 97.5 percent and a negative predictive value of 99 percent in all patients.

Without any thromboembolic risk factors, there was only a 0.95 percent chance of a CT angiogram positive for PE, according to Dr. Mamlouk.

"Thromboembolic risk factor assessment is an effective clinical method to determine when to perform CT angiography for PE," Dr. Mamlouk said. "Risk assessment can be performed when clinicians acquire their patients' history. It takes only a few minutes, and there's no cost."

Dr. Mamlouk and colleagues also concluded that the combination of no risk factors and a negative D-dimer, a blood test that helps in the diagnosis of blood clots, yielded an extraordinarily low risk for a positive CT angiogram for PE.

"Pulmonary Embolism at CT Angiography: Implications for Appropriateness, Cost, and Radiation Exposure in 2,003 Patients." Collaborating with Dr. Mamlouk were Eric vanSonnenberg, M.D., Rishi Gosalia, M.D., David Drachman, Ph.D., Daniel Gridley, M.D., Jesus G. Zamora, M.D., Giovanna Casola, M.D., and Sanford Ornstein, M.D.

Radiology is edited by Herbert Y. Kressel, M.D., Harvard Medical School, Boston, Mass., and owned and published by the Radiological Society of North America, Inc. (http://radiology.rsnajnls.org/)

RSNA is an association of more than 44,000 radiologists, radiation oncologists, medical physicists and related scientists committed to excellence in patient care through education and research. The Society is based in Oak Brook, Ill. (RSNA.org)

For patient-friendly information on CT angiography, visit RadiologyInfo.org.

Linda Brooks | EurekAlert!
Further information:
http://www.rsna.org
http://RadiologyInfo.org

More articles from Studies and Analyses:

nachricht Study relating to materials testing Detecting damages in non-magnetic steel through magnetism
23.07.2018 | Technische Universität Kaiserslautern

nachricht Innovative genetic tests for children with developmental disorders and epilepsy
11.07.2018 | Christian-Albrechts-Universität zu Kiel

All articles from Studies and Analyses >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Unraveling the nature of 'whistlers' from space in the lab

A new study sheds light on how ultralow frequency radio waves and plasmas interact

Scientists at the University of California, Los Angeles present new research on a curious cosmic phenomenon known as "whistlers" -- very low frequency packets...

Im Focus: New interactive machine learning tool makes car designs more aerodynamic

Scientists develop first tool to use machine learning methods to compute flow around interactively designable 3D objects. Tool will be presented at this year’s prestigious SIGGRAPH conference.

When engineers or designers want to test the aerodynamic properties of the newly designed shape of a car, airplane, or other object, they would normally model...

Im Focus: Robots as 'pump attendants': TU Graz develops robot-controlled rapid charging system for e-vehicles

Researchers from TU Graz and their industry partners have unveiled a world first: the prototype of a robot-controlled, high-speed combined charging system (CCS) for electric vehicles that enables series charging of cars in various parking positions.

Global demand for electric vehicles is forecast to rise sharply: by 2025, the number of new vehicle registrations is expected to reach 25 million per year....

Im Focus: The “TRiC” to folding actin

Proteins must be folded correctly to fulfill their molecular functions in cells. Molecular assistants called chaperones help proteins exploit their inbuilt folding potential and reach the correct three-dimensional structure. Researchers at the Max Planck Institute of Biochemistry (MPIB) have demonstrated that actin, the most abundant protein in higher developed cells, does not have the inbuilt potential to fold and instead requires special assistance to fold into its active state. The chaperone TRiC uses a previously undescribed mechanism to perform actin folding. The study was recently published in the journal Cell.

Actin is the most abundant protein in highly developed cells and has diverse functions in processes like cell stabilization, cell division and muscle...

Im Focus: Lining up surprising behaviors of superconductor with one of the world's strongest magnets

Scientists have discovered that the electrical resistance of a copper-oxide compound depends on the magnetic field in a very unusual way -- a finding that could help direct the search for materials that can perfectly conduct electricity at room temperatur

What happens when really powerful magnets--capable of producing magnetic fields nearly two million times stronger than Earth's--are applied to materials that...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

Within reach of the Universe

08.08.2018 | Event News

A journey through the history of microscopy – new exhibition opens at the MDC

27.07.2018 | Event News

2018 Work Research Conference

25.07.2018 | Event News

 
Latest News

Staying in Shape

16.08.2018 | Life Sciences

Diving robots find Antarctic seas exhale surprising amounts of carbon dioxide in winter

16.08.2018 | Earth Sciences

Protein droplets keep neurons at the ready and immune system in balance

16.08.2018 | Life Sciences

VideoLinks
Science & Research
Overview of more VideoLinks >>>