REGRESSION OF HIV ENCEPHALOPATHY AND BASAL GANGLIA SIGNAL INTENSITY ABNORMALITY AT MR-IMAGING IN PATIENTS WITH AIDS AFTER THE INITIATION OFPROTEASE INHIBITOR THERAPY

PURPOSE: To determine whether protease inhibitors cause regression of periventricular white matter signal intensity abnormalities in patient s with human immunodeficiency virus (HIV) encephalopathy and whether t he changes on magnetic resonance (MR) images correlate with cognitive improvement. MATERIALS AND METHODS: MR images were retrospectively and prospectively analyzed in 16 adult patients with HIV encephalopathy. White matter and basal ganglia signal intensity abnormalities on initi al long repetition time (TR) images were compared with those on subseq uent long TR images in patients who received and in patients who did n ot receive protease inhibitors. Clinical correlation was obtained. RES ULTS: Of the nine patients receiving protease inhibitors, four showed nearly complete regression, four showed interval stability, and one sh owed slight progression. Thus, eight patients (89%) demonstrated eithe r stability or improvement in white matter disease, which correlated w ith cognitive improvement. Of the seven patients not receiving proteas e inhibitors, six (86%) showed marked progression with a decline in co gnitive function and one had no interval change. The difference betwee n the two groups was statistically significant. Of the two patients re ceiving protease inhibitors who initially had basal ganglia signal int ensity abnormalities, one demonstrated resolution and one nearly compl ete resolution subsequently. CONCLUSION: Although the patient populati on is small, protease inhibitors may cause regression of periventricul ar white matter and basal ganglia signal intensity abnormalities in HI V encephalopathy and may have a role in treatment.