PROTON MRS AND QUANTITATIVE MRI ASSESSMENT OF THE SHORT-TERM NEUROLOGICAL RESPONSE TO ANTIRETROVIRAL THERAPY IN AIDS

Objective-To investigate MRI and proton spectroscopy changes in five p atients with HIV associated dementia complex (HADC) treated with antir etroviral therapy. Methods Three markers were evaluated: (1) CSF/intra cranial volume ratio; (2) T2 weighted signal ratio between parietoocci pital white and subcortical grey matter; and (3) metabolite ratios fro m long echo time (TE=135 ms) single voxel proton spectra of parieto-oc cipital white matter. Results-Spectroscopic changes indicated initial increases in N-acetyl/(N-acetyl + choline + creatine) ratio (NA/(NA+ C ho+Cr)) and progression of atrophy after initiation of antiretroviral therapy in four of five patients. When the neurological status of the patients subsequently deteriorated (two of five patients), the NA/(NACho+Cr) ratio also declined. Conclusions-spectroscopic changes mirror reversible neuronal dysfunction. These objective, non-invasive techniq ues may be used for monitoring the neurological effects of antiretrovi ral drug therapy in patients with HADC.