New CZT-based cardiac nuclear imaging system now at Mount Sinai Medical Center

Apr 12 2010

The Mount Sinai Medical Center has become the first in the United States to commercially use a new cardiac nuclear imaging system by GE Healthcare, a cadmium zinc telluride (CZT)-based high-speed, high-resolution camera that drastically reduces imaging time for patients while also reducing radiation exposure compared to previously used technologies.

"The device provides detailed pictures of the heart that enable Mount Sinai physicians to quickly and more accurately assess the location, extent, and severity of heart disease," said Milena J. Henzlova, MD, Professor of Medicine (Cardiology), Mount Sinai School of Medicine. "The new CZT-based nuclear cameras have already made a big difference in evaluating our patients for coronary artery disease. In addition to significantly reducing patient radiation exposure and increasing the number of patients we can examine each day, this technology provides a cost-effective way for us to diagnose heart disease quickly and with confidence so that patients receive treatment sooner."

With conventional nuclear cardiac imaging, patients must hold their arms above their head for two cardiac scans that take between 15-20 minutes each. With the Discovery NM 530c, the scanning time is reduced to 3-5 minutes for each scan. This reduction can be more comfortable for a patient, and it can possibly reduce imaging artifacts caused by patient movement. A shorter, more comfortable scan has the opportunity to improve image quality, allowing Mount Sinai clinicians to be more confident in their diagnosis.

At the recent American College of Cardiology annual scientific session in Atlanta (ACC.10), Dr. Henzlova and colleagues presented data showing that the new CZT camera technology also improves cardiac imaging while reducing radiation exposure. Patients in their study were divided into three groups based on the type of test they received to evaluate their heart health: a cardiac stress test with a low isotope dose, a cardiac stress test with a high isotope dose, and the traditional two part test where the patient is given a low dose of radiation while resting and a high dose during a stress test. Researchers compared the image quality using all 3 different isotope doses using the Discovery camera.

Results showed that the proportion of patients with excellent or good image quality was similar in all 3 groups (91-98 percent). However, compared to the traditional testing in the rest-stress group, radiation was decreased on average by 70 percent in the low dose stress-only group and by 30 percent in the high dose stress-only group.

Alcyone technology consists of four elements:

• CZT (cadmium zinc telluride) detectors - For improved image resolution;

• Focused pin-hole collimation - For improved detection efficiency, resulting in greater image clarity and speed;

• Stationary data acquisition - All views are acquired simultaneously during a fully stationary SPECT acquisition. This huge decrease in moving parts virtually eliminates the risk of motion artifacts and significantly shortens scan times;

• 3D reconstruction - To generate accurate and easily interpretable images of the myocardial region.

Nuclear cardiology studies are an important diagnostic test for detecting the presence of cardiovascular disease (CVD), the single leading cause of death in the U.S. today. According to the American Heart Association (AHA), approximately 1 in 3 deaths are attributed to CVD and, as the baby boomer generation ages, it is expected that these statistics will continue to rise. Yet CVD is a disease of all ages. In 2005, the AHA reported that approximately 151,000 Americans under the age of 65 died from CVD.

The Mount Sinai Medical Center is the first laboratory in the United States to receive accreditation for the use of the camera from the Intersocietal Accreditation Commission. Mount Sinai currently has two Discovery NM 530c units in use.