Featured Research

from universities, journals, and other organizations

Latest findings in CT radiation dose reduction efforts

Date:
August 4, 2010
Source:
Mayo Clinic
Summary:
In recent years, advances in CT scanner technology have made perfusion computed tomography imaging an important diagnostic tool for patients with suspected stroke. Now, researchers are working to reduce radiation dosages used to acquire perfusion and other CT images.

In recent years, advances in CT scanner technology have made perfusion computed tomography (CT) imaging an important diagnostic tool for patients with suspected stroke. Now, researchers at Mayo Clinic are working to reduce radiation dosages used to acquire perfusion and other CT images.

Related Articles


Mayo Clinic medical physicist Cynthia McCollough, Ph.D., and her group of researchers presented their findings related to CT dose reduction at the 52nd Annual Meeting of the American Association of Physicists in Medicine on July 20 in Philadelphia. The presentation was entitled "20-Fold Dose Reduction Using a Gradient Adaptive Bilateral Filter: Demonstration Using in Vivo Animal Perfusion CT."

"We believe in the clinical value of perfusion CT, and though there is no documented risk of injury at the currently prescribed radiation levels, we are trying to lower the dose for the benefit of patients," says Dr. McCollough, diagnostic radiologist, Mayo Clinic.

The As Low As Reasonably Achievable, or ALARA, principle has always guided Mayo Clinic's approach to the dosages of radiation used to acquire CT images. Dr. McCollough's team has been experimenting with a newly created image-processing algorithm that produces high-quality perfusion CTs with up to 20 times less the radiation used under existing protocols. Depending on the diagnostic application, a perfusion CT exam takes about 30 seconds to scan the tissue multiple times after iodine has been injected. This technique detects changes in blood volume and flow that reveal injuries to vessels or a tumor's response to treatment. Information from each consecutive scan is then digitally cross-referenced with other images taken during the exam to improve image quality and reduce distortions.

Thus far, the new perfusion CT algorithms have proved effective in animal models, and Dr. McCollough's team has begun looking at ways to introduce the methodologies into clinical practice.

"When we use very low doses of radiation to acquire a CT, image graininess can significantly decrease the value of the exam," says the study's first author, Juan Carlos Ramirez Giraldo, Mayo Clinic. "With this new algorithm, we are able to maintain the image quality by cross-referencing it with other images collected during the exam."

In related efforts, using one of the latest CT scanners on the market, Mayo Clinic already has other advanced algorithms as part of its clinical practice. A team of radiologists and physicists have recently implemented a new routine head CT protocol that cuts radiation dose by nearly 50 percent. While the American College of Radiology allows its accredited facilities to use head CT doses up to approximately 75 mGy, Mayo Clinic's newly introduced patient protocol uses a dose of only 38 mGy. This dose reduction is particularly significant as head CT exams are one of the most commonly performed CT procedures.

When asked how the new head CT protocol is changing clinical practice, neuroradiologist David DeLone, M.D., Mayo Clinic, says, "patients aren't aware that anything has changed, and as radiologists looking at a study, we don't know anything has changed. Yet, we are obtaining high-quality images, more consistently and in shorter times, while exposing patients to about half of the radiation dose. It's a win-win for everyone."


Story Source:

The above story is based on materials provided by Mayo Clinic. Note: Materials may be edited for content and length.


Cite This Page:

Mayo Clinic. "Latest findings in CT radiation dose reduction efforts." ScienceDaily. ScienceDaily, 4 August 2010. <www.sciencedaily.com/releases/2010/08/100803152821.htm>.
Mayo Clinic. (2010, August 4). Latest findings in CT radiation dose reduction efforts. ScienceDaily. Retrieved December 25, 2014 from www.sciencedaily.com/releases/2010/08/100803152821.htm
Mayo Clinic. "Latest findings in CT radiation dose reduction efforts." ScienceDaily. www.sciencedaily.com/releases/2010/08/100803152821.htm (accessed December 25, 2014).

Share This


More From ScienceDaily



More Matter & Energy News

Thursday, December 25, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Tech's Next Step: Social Change

Tech's Next Step: Social Change

Reuters - Business Video Online (Dec. 23, 2014) — Technology is constantly changing lives but 100 firms have done more than most. As Joel Flyn reports a malaria diagnosis app, do-it-yourself architecture and camera glasses have recently won awards for driving social change. Video provided by Reuters
Powered by NewsLook.com
Google Releases 'Fully Functional' Driverless Car Prototype

Google Releases 'Fully Functional' Driverless Car Prototype

Newsy (Dec. 23, 2014) — Google hopes to have a driverless car on the roads in California in 2015. Video provided by Newsy
Powered by NewsLook.com
Hopes Ride High for Classic Car Boom in Havana

Hopes Ride High for Classic Car Boom in Havana

Reuters - Business Video Online (Dec. 23, 2014) — Cuba's vintage cars may see new roads ahead as restored diplomatic relations with the U.S. raise hopes of an American tourist boom to see the 1950s 'yank tanks'. Deborah Lutterbeck reports. Video provided by Reuters
Powered by NewsLook.com
Heads Up for Touch-Free Smartphone

Heads Up for Touch-Free Smartphone

Reuters - Business Video Online (Dec. 23, 2014) — A touch-free phone developed in Israel enables the mobility-impaired to operate smart phones with just a movement of the head. Suzannah Butcher reports. Video provided by Reuters
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
 
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:  

Breaking News:

Strange & Offbeat Stories

 

Space & Time

Matter & Energy

Computers & Math

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:  

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile iPhone Android Web
Follow Facebook Twitter Google+
Subscribe RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins