Monday, May 22, 2006

Image Rx

By Keith Regan

Massachusetts General Hospital pioneered the technology of digital tomosynthesis. The alternative to traditional mammograms uses technology similar to a CT-scan to create a 3-D image that is far easier to read than the two-dimensional mammogram.

One of the drawbacks of the technology was that it took a large bank of computers to synthesize the images and create something a radiologist can read.

Thanks to advances in video-game technology, that's no longer the case.

Recently, however, working with Mercury Computer Systems Inc. of Chelmsford and Calif.-based video chip maker Nvidia Corp., Mass General devised a system that enables a single personal computer to do that same level of work and produce images that are clear enough to avoid a high percentage of callbacks, in which women undergo follow-up mammograms.

Rick Moore, research director in the Avon Comprehensive Breast Health Care Center at Mass General, said mammograms have been proven to save women's lives, but still pose challenges for doctors.

"Reading a two-dimensional mammogram is like trying to read a book with transparent pages," he said. Tomosynthesis enables separation of those pages, so that tumors can be spotted earlier and with more clarity.

With the video image-processing chip in place, Moore said, a PC can produce in three minutes the results that once took three hours.

The advance is just one example of how advances in other fields -- from technology to nanotechnology to broadband communications -- are helping doctors to more quickly and accurately spot health problems, which in turn can help save lives since early detection of many illnesses, particularly cancer, has been proven to reduce mortality.

Just across the river from Mass General, at MIT, researchers hope nanoparticles can help speed detection of cancerous tumors, by alerting doctors to tumors long before they are visible to the naked eye.

The approach being tested by Sangeeta Bhatia, associate professor of the Harvard-MIT Division of Health Sciences and Technology, uses certain nanoparticles -- in this case, those made of iron oxide -- that group together around cancerous tumors in their early stages of formation. If they can be focused on a nascent tumor, the particles could then become a mass themselves that is large enough to be detected.

Researchers say nanotechnology holds additional promise in the medical field, with those particles one day being capable of not only locating but attacking tumors as they form.

Enhanced imaging is also the goal of Brain Saving Technologies Inc., a Wellesley startup that seeks to use telecommunications and the ability to instantly send CT scans and live images, to help bring early diagnosis of stroke and other brain ailments, especially to remote areas where specialized doctors often are not located.

Founder Dr. Colin McDonald said vast areas of the country are not served by a qualified stroke-treatment center, yet treatment for stroke is most effective when administered rapidly after a patient arrives at a hospital.

"Communications and imaging technology have evolved to the point where remote diagnosis is possible in some cases," he said.

Despite still-evolving rules about insurer reimbursements, demand is strong for diagnostic imaging solutions, said Frost & Sullivan analyst Martin Bryant, with health care companies willing to invest heavily in technologies that can detect disease early.

"Patients are demanding more accurate diagnoses and that's driving the search for better solutions," he said.

Moore said benefits of the tomosynthesis breast-screening technique include fewer callbacks for women whose initial mammograms have uncertain readings and help persuade more doctors to enter the radiology field. The field has some of the highest lawsuit rates, which has helped drop the number of applicants for residencies in the field at Mass General from 20 a year to one.

"With this technique, tumors that can't quite be seen on mammograms are easy to see," he said. Preliminary data from the trial shows a dramatic reduction in call-back tests, enough to eliminate the need for between 1 million and 3 million secondary exams annually. "Mammograms already save women's lives and this can do even more," he added.

Keith Regan is a freelance writer based in Grafton.