Magnetic resonance spectroscopy, a form of magnetic resonance imaging technology that generates spectrums rather than images, could be the definitive tool for diagnosing bipolar disorder, according to a study presented Tuesday at the annual meeting of the Radiological Society of North America in Chicago.
Using MR spectroscopy, researchers at the Mayo Clinic in Rochester, Minn., detected significant differences between the brain chemistries of 21 people already diagnosed with bipolar disorder, which is characterized by extreme swings in emotions, and a control group of 21 people without the disorder. Preliminary findings indicated that in four areas of the brain that control behavior, certain metabolite levels differed significantly.
With luck, MR spectroscopy could become the gold standard for diagnosis of the disorder in two to three years, said John Port, M.D., assistant professor of radiology and consultant at the Mayo Clinic. Bipolar disorder, which affects approximately 2.3 million Americans, is now diagnosed by psychiatrists on the basis of symptoms and family history; patients often go undiagnosed for years.
In other RSNA news, radiologists reported an alarming increase in the number of diagnostic imaging tests performed by nonradiologists. After analyzing procedure, specialty and location codes from Medicare between 1997 and 2002, they found that utilization rates rose 11.6% among radiologists, 23.5% among all nonradiologists, and 42.2% among cardiologists.
Meanwhile, the proportion of noninvasive diagnostic imaging tests performed in hospitals fell to 28.4% from 33.6% while it rose to 32.6% from 28.1% in private offices and imaging centers.
Medicare reimbursement for MRI services increased six times the rate (599%) for orthopedic surgeons than for radiologists (99%) during the same period, it was reported.
