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Recently, Stony Brook University Medical Center became the first on Long Island to have a 320-slice CT scanner installed in its Emergency Department (ED) for use, in particular, with patients who have chest pain or a suspected heart attack. World-renowned cardiologist and imaging specialist Michael Poon, MD, explains what this means for both individuals and the community.

What is a 320-slice CT scanner and how does it differ from other CT scanners?
In essence, a 320-slice CT scanner is a faster and more accurate CT scanner. Where typical CT scanners take 10 to 20 seconds to get an image of the heart, this state-of-the-art technology acquires it in less than one second - in a single heartbeat. In addition, an extremely low dose of radiation is delivered due to the way we are using these machines at Stony Brook.

Why is this speed so important?
Speed is important for several reasons. One is that the longer you scan someone, the more radiation he or she is exposed to, making a faster imaging technique a safer one. Second, because the scan takes just one second, it will obtain a more accurate image. During a scan, a patient must not breathe, blink, or swallow. It is a lot easier to do this for just one second's duration than for the typical 10 to 20 seconds that less advanced machines take. If a patient moves, we have to repeat the scan, which exposes them to more radiation.

What is the reason for placing this equipment in the Emergency Department?
This is the perfect location because chest pain is one of the most common reasons people come to the emergency room. In fact, there are almost six million visits to the ED across the country each year by people with chest pain symptoms. In many cases, heart attacks are difficult to diagnose, but with the 320-slice CT scanner we can tell if a patient has had a heart attack or not, then treat that patient immediately and appropriately.

To illustrate what a difference this technology makes, I need to first explain how emergency rooms typically treat chest pain. Most take what I call a "one-size-fits-all" approach, which can keep someone at the hospital for up to 24 hours. Typically, patients who complain of chest pain will first have an EKG (electrocardiogram). If a blockage is revealed, the patient will be sent to the cardiac catheterization lab for treatment. If the EKG is normal, patients then have a blood test that looks for evidence of heart damage through the presence of certain enzymes. If this test is inconclusive, patients are kept at the hospital in order to repeat the blood test six hours later. If that is still inconclusive, doctors will schedule a stress test, which is done only during business hours. This may mean an overnight stay at the hospital, then more blood work. It can be a long, stressful, and disruptive process.

At Stony Brook, however, after the first blood test, patients can have the CT scan. If it is negative, they can go home knowing that they did not have a heart attack. The CT scan can also reveal other conditions, such as blockages and the presence of soft plaque that hasn't yet hardened. This provides patients information about the early signs of disease that they can then work to control. In addition, the entire process from admittance to the ED to discharge typically takes about six hours, which is more than two-thirds less time than the more conventional approach, and it also involves less stress and less disruption to a patient's life.

Why is Stony Brook the only ED in Suffolk County to have this technology?
It comes down to a couple of key things: The Hospital's focus on staying on the cutting edge of technology, Stony Brook's commitment to being a community resource, and the expertise of the people who run the program and operate the equipment. When I was recruited to Stony Brook a year ago, I began building a program - training nurses, technologists, physician assistants, and other support staff, and putting protocols in place - so we could maximize the CT scanner technology. We started performing cardiac CT scans every day and documented the difference it made in patient care, outcomes, and costs. We purchased a 320-slice CT scanner for the ED because of the vast benefits it offers, and it has changed the way the ED assesses chest pain.

So you are saying the real Stony Brook difference in this case is the expertise behind the equipment?
Absolutely. At Stony Brook University Medical Center, every cardiac scan is either done by me or in the presence of a physician trained by me in low-dose cardiac imaging. Since I joined Stony Brook, I have been available 12 hours a day, 7 days a week to either perform or oversee and read every scan.

It is critically important to have an experienced physician perform and read the scan versus a technologist. It takes years of study to perfect the precise nuances of delivering the lowest dose possible for each individual patient. It is a very particular specialization that takes into account a number of factors. A trained eye and extensive experience are necessary for optimal results.

Since January 2009, more than 600 scans have been performed at Stony Brook University Medical Center for evaluation of acute chest pain, with no adverse outcomes to our patients.