Radiologist Dr. Jeffrey Dardinger is opening images of a heart — looking as real as the human specimens on display at the “Bodies” exhibit — on one of several huge flat-screen monitors lined up in his office at St. Elizabeth Medical Center in Edgewood.

Using specialized software, Dardinger guides his cursor to rotate the heart, which is visible in full dimensions from all angles. Clicking on a major artery, he gets an interior view that reveals an alarming amount of blockage.

These images from a computed tomography (CT) system — often called CAT scanning — represent one example of the advanced medical imaging technology now being employed in the Tristate.

“It used to take a tech sitting at a work station over an hour to cut out a usable image of the heart,” Dardinger notes. “Now the computer does it by itself in under one minute.”

The ability to see color three-dimensional pictures of a heart, brain, muscle or bone allows doctors to see the insides of patients without having to cut anything open.

Dardinger opens another file to show a heart beating, with blood flowing in the ventricles highlighted in neon green. “This is called 4D technology,” he explains with obvious excitement. “In the old paradigm we were looking at anatomy, which is static. In the new design, we’re able to look at physiology — the body in motion.”
IMAGING ARMS RACE

As with most metro regions in the U.S., Greater Cincinnati is witnessing an arms race in medical imaging. Hospitals try to out-do each other with the latest technology. Independent imaging centers, often started by physicians, add to the competitive mix. (See a primer on what’s new, page 60). Atruistically, these healthcare providers want to deliver better care. Business-wise, they want to capture and hold market share.
Patients may not shop around and compare 1.5 and 3.0-Tesla magnetic resonance imaging (MRI) systems, but physicians do — and the operators of the advanced, expensive systems seek to lure those doctors, who place the imaging orders.

There’s seemingly no end to the debates over cost-benefit analysis of these imaging systems. No doubt, in many instances the early detection of disease — especially cancer — not only saves or extends lives, but also saves the stressed healthcare system millions of dollars.

The competition is especially evident with advanced in CT technology. The recent advent of so-called 64-slice CT, which refers to the number of X-ray detectors in the unit, was especially exciting to cardiologists. The increased imaging speed allows the visualization of the inside condition of coronary arteries, in what is now called CT angiography.

What does that mean to the person who is rushed to the hospital with a suspected heart attack? A typical angiogram requires inserting a catheter into an artery to inject a contrast chemical, then using more conventional X-rays to see what’s going on — the process called cardiac catheterization. CT angiography — also called CCTA — is faster, can produce superior images and is less invasive. No contrast agent has to be injected in some cases.

“CCTA can detect plaque inside arteries much easier,” says Rod Willis of ProScan Imaging. “It can detect soft spots that can break loose from artery walls and may lead to heart attacks. There have been some young, seemingly healthy people who have been diagnosed this way.”

Dr. Wojciech Mazur, a cardiologist for Ohio Heart & Vascular Center who serves on the Christ Hospital staff, sees many life-saving applications for advanced CT. “It’s the first non-invasive technique that allows a complete visualization of coronary arteries,” he notes.
“There are three potential fatal causes of chest pain,” Mazur continues. “An aortic dissection, a pulmonary embolism and a blocked artery. With a CT scan, you can rule out all three. They call it a triple rule-out. In some ERs, it is common practice to do a CT scan on a patient presenting with chest pain. However, you have to have a 64-slice scanner, which not all hospitals have.”

The next generation of computed tomography takes a huge leap to a scanner that can capture 250 to 320 image slices.

Cincinnati is on the cutting edge of this technology. St. Elizabeth Hospital has been approved to buy a 320-slice scanner. The system is slated to be installed in late summer. The cost to the hospital is $2.5 million dollars, although the list price is closer to $3 million.

There are only five 320-slice scanners currently installed worldwide. “We’ll be in the top 20 in the world, and the first in the Cincinnati area,” Dardinger says.

Christ Hospital also is looking into investing in a 320-slice CT system.

“The progress that’s been made in this technology is truly amazing,” Dardinger observes. “The first single-slice scanner came onto the market in the 1980s. The four-slice scanner came out in the late 90s.”

Radiation exposure remains a big concern about advanced imaging like computed tomography that still relies on X-rays. As Mazure notes, a CT session can deliver the equivalent of 50 to 100 chest X-rays. That’s why doctors tend to avoid ordering CT scans for younger patients, except in the most critical cases.

With faster scanners, however, the process takes less time and lowers the total radiation dose.

“In the old days, the CT scans would image 1 centimeter at a time,” Dardinger explains. “Things were kind of blurry. Now we’re doing 5 centimeters at a time — so it’s basically twenty-fold better. Before, it could take two to three hours before someone said, ‘Yes, you had a stroke’ with the old system. Now you can do in less than 30 minutes what used to take three hours.”