RT Journal Article SR Electronic T1 Magnetization transfer study of HIV encephalitis and progressive multifocal leukoencephalopathy. Groupe d'Epidémiologie Clinique du SIDA en Aquitaine. JF American Journal of Neuroradiology JO Am. J. Neuroradiol. FD American Society of Neuroradiology SP 895 OP 901 VO 18 IS 5 A1 V Dousset A1 J P Armand A1 D Lacoste A1 S Mièze A1 L Letenneur A1 J F Dartigues A1 J M Caill YR 1997 UL http://www.ajnr.org/content/18/5/895.abstract AB PURPOSE To ascertain whether the use of magnetization transfer (MT) in MR imaging can characterize tissue destruction in human immunodeficiency virus (HIV)-positive patients with presumed progressive multifocal leukoencephalopathy (PML) or HIV encephalitis.METHODS Brain MR studies that included MT were obtained in three groups: 11 healthy control subjects, 10 HIV-positive patients with clinical and radiologic findings of PML, and 13 HIV-positive patients with HIV encephalitis. MT ratios (MTRs) were calculated in PML and HIV encephalitis lesions and in normal-appearing white matter in the patients and control subjects.RESULTS PML lesions revealed a dramatic decrease in MTR (22% +/- 2.3). HIV encephalitis lesions had statistically significantly higher MTR values (40% +/- 3.8) than PML lesions. The MTR of normal-appearing white matter was significantly higher in the control subjects (47% +/- 2.3) than in the PML group (46% +/- 3.3) or the HIV encephalitis group (44% +/- 2.6).CONCLUSION MTR determinations suggest the possibility of distinguishing PML from HIV encephalitis and of indicating whether HIV encephalitis is involved in white matter that appears normal on conventional MR images.