MRI technique for measuring blood volume helps distinguish between abscesses and tumors in the brain

Dynamic susceptibility contrast (DSC) MRI allows physicians to differentiate between cerebral abscesses—inflamed areas in the brain caused by infection—and malignant brain tumors without surgery, says a new preliminary study by researchers from Duke University Medical Center in Durham, NC.

For the study, the researchers analyzed eight patients who underwent DSC MRI—four with cerebral abscesses and four with malignant brain tumors. DSC MRI is used to measure blood volume in brain tumors. Malignant brain tumors have high blood volume because they need new blood vessels in order to grow, while abscesses have the same blood volume as healthy tissue. On analyzing maps produced by DSC MRI of cerebral blood volume in these eight patients, the researchers found no overlap in the blood volume between the group of abscesses and the group of tumors .

According to the researchers, DSC MRI and traditional MRI are fundamentally different in the types of information they provide. “Regular MRI scans show the size and shape of a muscle or organ very well, but they don’t tell us much about how it is functioning. As we get more sophisticated in imaging organs, we want to know more than simply their size and the shape. DSC MRI gives us that additional necessary information, letting us know the vascular needs of the tissue ,” said James M. Provenzale, MD, one of the authors of the study.

Distinguishing between abscesses and tumors is a frequent problem for radiologists. “The distinction between abscess and tumor can be made by surgically removing tissue from the brain, but one would rather make the diagnosis by a noninvasive measure. The treatments for the two entities are also different: antibiotics for abscesses and surgical removal, chemotherapy or radiation therapy for tumors. A worst-case scenario would be one in which the wrong treatment is given for weeks or months due to a misdiagnosis,” said Dr. Provenzale.

The article appears in the November 2004 issue of the American Journal of Roentgenology.

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