THE VIRGINIAN-PILOT
Copyright (c) 1995, Landmark Communications, Inc.
DATE: Tuesday, March 28, 1995 TAG: 9503280289
SECTION: FRONT PAGE: A6 EDITION: FINAL
SOURCE: ASSOCIATED PRESS
DATELINE: NEW ORLEANS LENGTH: Medium: 53 lines
Millions of Americans know they should have their colons checked for cancer but can't stand the thought of it. So doctors are developing a decidedly less unpleasant alternative - a colon exam without the tube.
Dr. David J. Vining of Wake Forest University, the principal developer of the new method, calls it ``virtual colonoscopy,'' a way to combine X-rays and computers to examine the entire colon without actually putting anything into it except air.
Colon cancer is the No. 2 killer of men and women after lung cancer. This year, an estimated 55,300 Americans will die from it.
The mainstay of screening for this disease is a skinny, flexible tube that is inserted through the rectum into the colon. The doctor looks through the tube for growths called polyps that may be cancerous.
The American Cancer Society and other health organizations recommend that people over 50 be checked with sigmoidoscopy, an exam of the lower third of the colon, every three to five years. If this reveals any possible problems, the next step is colonoscopy, which uses a longer tube to view the entire 4 to 6 feet of the colon.
Vining's idea, which he said was inspired by computer games, involves a relatively new form of X-ray technology called spiral CT. Ordinary CT scanners slowly take cross-sectional images of the body one picture at the time. The new machine spins around the patient and snaps 400 to 500 pictures in half a minute.
Vining uses two commercially available software programs to process the spiral CT data and turn it into a 3-D image.
Vining has tested it on 20 patients who were about to undergo regular colonoscopy. It accurately found the four who turned out to have cancer.
Before undergoing the test, patients must have their bowels flushed out. Then air is pumped into the colon. The exam itself takes just 30 seconds, and unlike colono-scopy, no sedation is required.
``Afterward, the patient gets off the table, passes wind and goes home,'' Vining said.
The new approach should also be cheaper. Vining estimated that an exam will cost $450 to $650, compared with $900 to $1,800 for colonoscopy.
However, even if further testing shows it can accurately find suspicious polyps, it will not eliminate the need for colonoscopy. That will still be necessary to remove polyps after doctors spot them with virtual colonoscopy.
Vining described his work this week at a science writers seminar sponsored by the cancer society. by CNB