Reported February 2007

BACKGROUND: A new software tool developed by computer scientists at Brigham Young University in Provo, Utah, will allow surgeons to instantly visualize any part of a patient's anatomy by extracting a 3-D computer image from an MRI, CT scan, 3-D ultrasound, or similar data with just a few clucks of the mouse. Called Live Surface, the software peel away body layers and extract specific types of tissue, bones and organs. It can also be used to extract a single actor's performance or inanimate objects from video clips.

HOW IT WORKS: The user identifies the object he wishes to extract by clicking and dragging the mouse, and then identifies those portions of the data that surround the object to extract it from the data. The program does this much more quickly than other similar software tools because it uses a hierarchical algorithm, or set of mathematical rules, that tells the computer to eliminate irrelevant information in broad, coarse cuts. Once the bulk of unwanted data is gone, the computer can make more refined calculations more quickly. After a surgeon has extracted a 3-D image of a person's heart or brain, for example, the image could then be projected onto the patient's body, fitted to create a road map for the surgeon as s/he operates.

BENEFITS: Instead of just showing patients the usual MRI, CT or ultrasound images in a few segmented slices, a physician can now show the patient exactly where the problem is, how big the tumor is, or rotate specific organs to get a view from all angles. Apart from helping radiologists and other physicians analyze patients' anatomy in better detail -- including locating hidden tumors -- the software tool can also help clinicians to better explain what is going on to patients

ABOUT CAT SCANS: CAT (Computerized Axial Tomography) scans are similar to conventional X-ray imaging, but instead of imaging the outline of bones and organs, a CAT scan machine forms a full 3-D computer model of the inside of a patient's body. Doctors can even examine the body one narrow slice at a time. The X-ray beam moves all around the patient, scanning from hundreds of different angles, and the computer takes all that information to compile a 3-D image of the body.

HOW MRI WORKS: Magnetic resonance imaging uses radiofrequency waves and a strong magnetic field instead of X-rays to provide clear and detailed pictures of internal organs and tissues. These radio waves are directed at protons in hydrogen atoms -- one of the most abundant atoms in the human body, because of the body's high water content. The waves "excite" the protons, and when they "relax," they emit strong radio signals. A computer can turn those signals into a high-contrast image showing differences in the water content and distribution in various bodily tissues.

The American Association of Physicists in Medicine contributed to the information contained in the TV portion of this report.

If you would like more information, please contact:

William Barrett, Ph.D.
Medical Biophysicist and Computer Scientist
Department of Computer Science
Brigham Young University
Provo, UT
(801) 422-7430
barrett@cs.byu.edu

Ben Stein
American Institute of Physics
(for the American Association of Physicists in Medicine)
(301) 209-3088
http://www.aip.org
bstein@aip.org

ON THE WEB...

Live Surface Images

Live Surface News Release