BRAIN-LESIONS IN PATIENTS WITH AIDS - H-1 MR SPECTROSCOPY

PURPOSE: To evaluate the role of proton (Hydrogen-1) magnetic resonanc e (MR) spectroscopy in the differential diagnosis of focal brain lesio ns in patients with acquired immunodeficiency syndrome (AIDS). MATERIA LS AND METHODS: Twenty-six men with 35 AIDS-related brain lesions unde rwent MR imaging and localized H-1 MR spectroscopy. Lesions consisted of 11 toxoplasmic abscesses, 12 progressive multifocal leukoencephalop athic lesions, eight lymphomas, and four cryptococcomas. Metabolite pe ak areas in the lesions were compared with those in the contralateral hemisphere in each patient RESULTS: H-1 MR spectroscopic findings show ed significantly different biochemical profiles for each diagnostic gr oup (P = .0001) with regard to N-acetyl compounds, total creatine pool , choline-containing compounds, myo-inositol, and lactate. H-1 MR spec troscopy alone helped correctly diagnose 94% (84% with jackknifed clas sification) of the brain lesions, without overlap between toxoplasmosi s and lymphoma. CONCLUSION: H-1 MR spectroscopy is a sensitive and pot entially specific noninvasive adjunctive method for differential diagn osis of focal brain lesions in AIDS.