The efficacy and clinical impact of brain imaging in neurologically symptomatic AIDS patients: a prospective CT/MRI study.

The relative efficacies of cranial magnetic resonance imaging (MRI) and computed tomography (CT) brain scans for the detection of intracranial pathology in patients with the acquired immune deficiency syndrome (AIDS) were evaluated prospectively. Fifty homosexual or bisexual men with AIDS and neurologic symptoms were evaluated using both modalities. In 24 patients, MR images and CT scans provided the same diagnostic information (within normal limits in 16, cerebral atrophy only in 6, and similar lesions in 2 patients). In only one instance did CT show the presence of a lesion not seen on MRI. In the 25 remaining patients, MRI was the more sensitive modality. MRI also reflected more consistently the histopathologically documented extent and distribution of central nervous system disease. The greater sensitivity of MRI suggested significant alterations in the diagnostic evaluation and therapeutic management of 20 patients. Thus, MRI was as good or better than CT for the detection of intracranial pathology in 49 of 50 neurologically symptomatic AIDS patients and significantly affected the diagnosis and treatment of 40% of these patients. Although MRI does not appear to be more specific than other modalities in the differentiation of human immunodeficiency virus (HIV)-related neurologic diseases, its greater sensitivity suggests that MRI may be the best neuroimaging procedure for the initial radiologic evaluation of AIDS patients with neurologic illness.