New Technology
Leading-Edge CT And MRI Scanners Aid Diagnosis, Treatment
Significant groups of patients - ranging from those with suspected heart disease or brain tumors to larger patients - will benefit from two leading-edge imaging technologies acquired by the University of Virginia Health System.
UVa's new dual source CT and 3T MRI provide higher-quality images and do so faster, enabling radiologists and cardiovascular specialists to diagnose more complex and difficult cases.
Here's a look at how patients benefit from individualized care made possible by each piece of state-of-the-art technology.
Dual Source CT
UVa is one of the first hospitals in the U.S. to purchase the dual source CT, which combines two 64-slice CT scanners into a single scanner. This CT is capable reducing scan time from 160 milliseconds to 80 milliseconds, says Klaus Hagspiel, M.D., chief of UVa's Division of Noninvasive Cardiovascular Imaging and a professor of radiology.
The machine's speed, Hagspiel says, means a CT scan can be performed regardless of a patient's heart rate, eliminating the need to give patients beta blockers to bring their heart rate to the 50 to 70 beats per minute range. Currently, patients whose hearts are beating faster than 70 beats per minute, or whose hearts have arrhythmias, produce blurry CT images.
"You can still get good images at high heart rates with the dual source CT," he says. The dual source scanner's speed can also significantly reduce patients' radiation exposure, he says.
Finally, the machine's high table weight and significant power boost provided by the dual source technology enables large patients to receive higher-quality imaging than would otherwise be possible.
The dual source scanner's primary application is for cardiac imaging, Hagspiel says. The images obtained on the CT directly benefit patients by ruling out heart disease in low- to medium-risk patients who are symptomatic, such as people who come into the emergency department or UVa's Chest Pain Center with chest pain, says Christopher Kramer, M.D., a professor of radiology and medicine. Those patients will be spared the potential risks from a cardiac catheterization. It also could substitute for a cardiac catheterization for pre-operative heart valve patients who need to rule out pre-existing coronary disease.
"It will likely reduce the number of negative invasive catheterizations over time," says Kramer, a cardiologist.
The dual source scanner provides excellent detail of the heart structure such as in congenital heart disease patients. The scanner also provides detail on the heart's function by measuring its ejection fraction.
The dual source scanner can also produce higher-quality joint imaging. For the first time, a single scan will be able to show both strong bone images as well as strong ligament and tendon images in one picture. Michael Dake, M.D., chairman of UVa's Department of Radiology, says doctors will be able to provide more information to patients, for example, who have arthritis, joint trauma and sports injuries.
3T MRI
The magnet in the 3T MRI is twice the strength of the typical MRI now in use, helping produce higher-quality, more detailed images, says C. Douglas Phillips, M.D., UVa's director of neuroradiology. The 3T MRI can also image very small structures that previously could not be done, Phillips says, such as cranial nerves. The ability to perform MR angiography is also improved because the 3T MRI is better able to identify small blood vessels.
Stroke patients and patients undergoing brain surgeries are among the chief beneficiaries of the scanner, Phillips says. Patients about to undergo resections of brain benefit from the improved ability of the 3T MRI to do functional MRI. The new scanner precisely locates brain tumors while simultaneously identifying key functional areas of the brain, such as the areas that control speech and motor functions. That allows surgeons to better pinpoint their approaches to target diseased or damaged areas of the brain while sparing healthy tissue, helping create better outcomes for patients.
"It helps us plan our surgeries better," says Mark Shaffrey, M.D., chair of the Department of Neurosurgery.
The new MRI will also aid in Diffusion Tensor Imaging (DTI), allowing better mapping of white matter tracts in the brain and elsewhere. For stroke patients, Phillips says, evaluation of the involved white matter tracts may aid in rehabilitation decisions, helping physicians plot an appropriate treatment course for each patient. DTI also helps detail how tumors, lesions or other masses may have displaced those white matter tracts, helping surgeons plan safer approaches.
The 3T MRI scanner is set up in a state-of-the-art room designed to maximize the magnetic purity of its setting and improve the signal-to-noise ratio, Phillips says, creating the clearest images possible.
To refer a patient for imaging with the dual source CT or 3T MRI, call UVa Physician Direct at 800-552-3723.