Radiology in Minnesota

CT Scanner Provides Enhanced Medical Imaging Capabilities

The Sensation 64 scanner takes more "slices" of the human body in a shorter scan time.

The new scanner produces images with incredible detail, as in this image of a patient's neck.

A new generation computed tomography (CT) scanner is helping Mayo Clinic researchers break new ground in the field of medical imaging by providing highly detailed images of small or moving structures, such as the inner ear, heart, arteries and veins.

Installed in July 2004, the SOMATOM Sensation 64 takes more "slices" of the human body (64 instead of the typical 16) in a shorter scan time. "There is a dramatic increase in the amount of information we can acquire from a single scan with this new system," says Mayo Clinic medical physicist, Cynthia McCollough, Ph.D. Mayo Clinic is the first medical facility in the U.S. to acquire a 64-slice scanner.

"We can image incredibly small details in a matter of seconds, without having to make compromises in spatial resolution (the amount of detail in an image), scan time or image quality. We expect the system to allow us to take CT imaging to new levels of performance and clinical utility," says Dr. McCollough.

With this new tool, researchers hope to move CT scanning beyond routine clinical imaging to explore advanced applications. Researchers will examine smaller areas and detect more diseases — including some that could not be imaged previously — throughout the body, including the complex neurological, cardiac, gastrointestinal and genitourinary systems. The tool also will allow researchers to detect diseases in their early stages and measure the severity of the disease.

Mayo Clinic radiologist, Dr. Joel Fletcher says the scanner will benefit some specific patient groups, such as severely overweight individuals. Current CT scanners cannot accommodate patients weighing more than 450 pounds, and can't image the entire body of obese patients because X-ray tubes often overheat. Because of a stronger scanner table (where the patient lies during the scan) and improved X-ray tubes, Sensation 64 expands the weight limit of patients who can be scanned to 615 pounds.

Patients will also benefit from the increased scanner speed. Depending on the area of the body being imaged, a conventional CT scan can take up to several minutes. A Sensation 64 scan takes only seconds. A child, for example, can be imaged in less than four seconds. The increased speed allows for the imaging of fast-moving structures, capturing pulsations of the heart's coronary arteries as well as cerebral aneurysms (enlarged arteries or blood vessels in the brain). It also uses less radiation during the imaging process, reducing patient radiation doses.

Mayo is working cooperatively with Siemens Medical Solutions, developers of the SOMATOM Sensation 64, in testing this new product. Siemens also provides funding to support research using Sensation 64. Mayo Clinic plans to acquire four 64-slice scanners for routine patient use in 2005.