Pictures of the Future      Fall 2005

The Perfect Patient

A first-of-a-kind operation takes place—the product of knowledge-guided systems. The only question is: where was the patient?...

Hi. That’s me, Dr. Victoria Taft on the left with Dr. Elsa Pla, our country’s Minister of Health. We’re touring my hospital’s Integrated Diagnostics and Surgical Intervention Center (IDSIC). It’s the first to have a new generation of treatment centers to be designed in a hub-and-spoke configuration. Patient through-put simulations found that this arrangement maximizes utilization of all the new hybrid imaging and information systems. For radiologists like me, it’s the coolest thing since frozen margaritas.

In general, IDSIC works like this: A data integration program analyzes each patient’s diagnostic, medical and therapeutic needs based on tests and physician recommendations and suggests the best combination of imaging and interventional modalities. Then, during treatment, imaging data are automatically fused with the patient’s medical history, and a database of age-matched patients provides probabilistic advice on each patient’s expected outcome as intervention occurs. By the way, IDSIC is part of a larger medical and academic complex that includes the Center for Living Memory, which you may have read about before (see Pictures of the Future, Fall 2004,  Living Memory). Elsa and I go back a long way—in fact, we roomed together back in med school. But today Elsa’s here on official business and she’s about to see something quite remarkable. Below the observation dome behind us is Dr. Jean Boudrou. He’s the head of our interventional services. He’s from France. A real sweetie. Today he’s going to perform the firstever replacement of a mitral valve using remotely controlled catheters. Normally, the mitral valve allows blood to flow in only one direction from one atrium to the adjoining ventricle in the heart. But in some patients it leaks so badly that it has to be replaced. It’s still a fairly common condition. Up until now, valve replacement meant opening the chest and the heart—not exactly minor surgery. This patient will be different.

As I told Elsa, the patient is an interesting guy. He’s Prof. Alan Carnadine, the head of the Center for Living Memory. We even had lunch together a few times back when the Center was preparing for its grand opening.

Over the last few days Jean—I mean Dr. Boudrou—examined him thoroughly. Carnadine’s digital health card indicated that he had had a mild case of rheumatic fever as a child and was on anti-depressants following a recent "personal event." He was also suffering from dizzy spells.

A digital audio analysis of his heart picked up a murmur and identified the sound as a mitral valve defect. A clinical decision support application not only analyzed all of Carnadine’s available imaging data to quantify exactly how much blood was being regurgitated with each heart beat, but also provided treatment recommendations.

By the time I had finished explaining the clinical situation to Elsa, the patient had been sedated, prepped for catheterization, and had undergone a combined computed tomography, magnetic resonance, and positron emission tomography (PET) analysis. We could see on the observation deck monitors that the CT scan had turned up no anatomical abnormalities—except for the mitral valve defect—and that the PET scan had found the entire myocardium to be healthy. In both cases, intelligent software applications automatically ran through all the data and provided Dr. Boudrou—and the patient’s electronic file—with the results.

Dr. Boudrou proceeded to examine the patient’s 3D MR chest scan. Automated alignment of image planes taken between heartbeats, the magnet’s very high field strength, and multi-RF channel design made it possible to examine the patient’s heart with extraordinary resolution. Based on that scan, a program calculated the exact size and shape of the required replacement valve, ordered a customized prosthesis from our ultra sterile automated production center, and marked the route to be taken by the catheter. Minutes later the prosthetic valve was delivered and mounted in the catheter’s tip.

Then the procedure began. With the patient well inside the MR scanner, Dr. Boudrou began guiding the remotely controlled catheter to its target using precision joy sticks. Elsa and I watched in fascination as a virtual 3D view from the catheter’s tip showed the dark red inner walls of the patient’s arteries gliding by as it followed a bright yellow navigation stripe superimposed on the actual realtime images.

Finally, the catheter eased into place at the site of the compromised valve. A magnified view appeared showing a virtual target point with which Jean lined up the tip of the actual catheter using a micron guidance feature on his joy sticks.

"Magnifique!" we heard Jean say to himself over the loudspeaker. Satisfied that the valve was exactly on target, he directed the catheter to discharge an electric impulse that stopped the patient’s heart. A second later, the first part of the prosthesis unfolded, flattening the patient’s faulty valve firmly against the inner wall of the atrium. The umbrella valve then unfurled from within the catheter, its microscopic hooks clamping themselves firmly over the perimeter of the old valve.

"Superb!" Jean exclaimed in his rich Parisian accent as a display, based on an analysis of all imaging angles, indicated that the hooks had seamlessly sealed the prosthetic device into place. A moment later a signal restarted the patient’s heart, and from our displays we could see and hear the new valve opening and closing normally.

"Extraordinary," Elsa said, when she turned to me. "I will recommend…" But then she noticed that something had changed. "Where’s the patient?" she asked, a look of disbelief on her face as she looked at the empty scanner bay. "Oh, my dear Elsa," I said. "What you just experienced was a full-scale simulation. The patient in the bay was an augmented reality projection—essentially a demonstration of IDSIC’s leadership in data fusion. In a few moments, the real patient will arrive."
                                                                                                           Arthur F. Pease