MR imaging of the brain in patients with AIDS: value of routine use of i.v. gadopentetate dimeglumine.

OBJECTIVE A prospective study was conducted to explore the value of routine administration of IV gadopentetate dimeglumine for MR imaging of the brain in patients with AIDS. SUBJECTS AND METHODS Over a 19-month period, MR images of the brain in 51 consecutive AIDS patients were obtained routinely both with and without IV gadopentetate dimeglumine. Unenhanced and contrast-enhanced images from the resulting 63 studies were viewed together. Findings were classified into one or more of three categories: normal, mass or focal lesions, or white matter disease. The number of focal or mass lesions was recorded. Lesion conspicuity on the unenhanced and enhanced images was compared. Ventricular enlargement was also graded. Available medical records and laboratory data of the patients were reviewed. RESULTS Of the 63 MR studies reviewed, 39 (62%) were abnormal. In no case was a normal unenhanced MR study rendered abnormal after the administration of gadopentetate dimeglumine. Overall, T2-weighted images showed twice as many focal or mass lesions than contrast-enhanced T1-weighted images did. Most lesions detected on the T2-weighted images did not show enhancement with contrast material. White matter disease was the most common abnormality detected. The group of patients with white matter disease also had the highest occurrence of ventriculomegaly. CONCLUSION Our study does not support the routine use of gadopentetate dimeglumine for MR imaging of the brain in patients with AIDS. Our experience emphasizes the importance of a normal T2-weighted image.