The new diagnostics

February 05, 2002

The new diagnostics

State-of-the-art ways of seeing into the body make it possible to know more, sooner, about illness


Gail Croft is an old pro at being poked, prodded and otherwise investigated by diagnostic machines.


Since April 2000, the cancer survivor - cervical and liver - has undergone two magnetic resonance imaging tests (MRIs), three positron emission tomography (PET) scans and eight computed tomography (CT) scans.

Enduring the procedures is no sweat now, but there was a time, leading up to her first scan, when she was less than enthused about taking a trip through the cumbersome, imposing diagnostic machines.

"I was scared, because I didn't know what to expect," says Croft, who is a Washington County Hospital emergency department patient advocate. "They gave me two big bottles of contrast to drink; they gave me a consent form to sign ... it kind of surprised me because I didn't know all of those things were going to be done."


Visiting the hospital is hard enough. Toss in a trip through a large, bulky machine taking pictures of the body and the experience can be downright frightening.

Yet, those same mammoth machines make it easier to diagnose health problems as diverse as a sprained knee or brain tumor.

And what once was science fiction is quickly becoming science fact as technology improves and creates faster scanners capable of taking more pictures that are more detailed than ever before. The result is a constant stream of improvements akin to the rapid evolution of computers, and hospital technicians working exclusively with one type of scanner must take part in ongoing education.

"The technology is to the point where there is a lot we can see," says Dr. Paul Marinelli, chief of the radiology department at Washington County Hospital. "But there are still a lot of things we can't see."

Where no one has gone before

Where X-rays take a single, two-dimensional picture of the abdomen, CT scans - basically a more advanced X-ray - take cross-sectional images that can create a three-dimensional model of the organ.

While CT scans are excellent for detecting bones and providing a general picture of the body, MRIs - which use giant magnets to take pictures - provide a more detailed look at soft tissue such as the brain.

The next generation of tests include the PET scan, which trumps its diagnostic cousin by detecting abnormal activity even before cancerous tumors would appear on a CT scan. It does this by taking scans that can isolate unusual levels of glucose metabolism in the body after the patient has been injected with a specially-treated glucose solution that outlines problem areas.

Each machine, Croft says, might look imposing to the uninitiated, but the scans themselves are simple. Patients need only lie still and let the machines do the work.

"They're not unpleasant," she says. "You just kind of lay there. If you can fall asleep, you can, if you can't you can't. I just try to let my mind wander."

And she can be in constant contact with the technicians overseeing her scans since each machine is outfitted with microphones.

Like the DVD player or computer that becomes cheaper over time, diagnostic tests are steadily becoming more affordable. Marinelli says cost varies but standard CTs can be as little as $250, MRIs up to $1,000.

At the same time, technology has improved to the point of taking faster, more in-depth pictures. Ten years ago, when MRIs first came on the scene, Lead MRI Technician Matt Compher says routine exams would last an hour. Today, the same test can be completed in half the time, with more images taken.

In time, noninvasive CTs and MRIs may replace colonoscopys to screen for colon cancer or be used to detect heart disease. Right now, in contrast, doctors insert a tube into the colon to find polyps or tumors and run a tube, usually from a patient's hip, up to the heart to determine if arteries are blocked. Conventional procedures would still be needed if a polyp, tumor or blockage is discovered.

Later this year, new and more efficient CT and MRI scanners will be introduced at Washington County Hospital and Robinwood Diagnostic Imaging Services. The equipment will be quicker and take more pictures, though results will not be instantaneous, Marinelli says.

Diagnosis is still an art

"There can be 525 pictures with one scan, and I have to read each one of those pictures," he says of the process of interpreting data.

"People have got the McDonald's mentality to it, and people need to realize it's as much art as science."

Having grown accustomed to the scans, Croft says the most aggravating part of the process is pre-scan preparation, drinking contrast fluid and waiting to enter the machines.

The scans themselves? Piece of cake. MRIs give her a little trouble - she feels claustrophobic - but her sister sits with her during the process.

Regardless of the test, Croft recommends asking as many questions as are necessary to put the mind at ease.

"Anything you don't know about you're going to be scared," she says. "It's important to maintain some sense of control because when you're already sick you've already lost some of your control. ... We as patients want information and it makes us feel better when we have that information."

The Herald-Mail Articles