BENIGN VERSUS SECONDARY-PROGRESSIVE MULTIPLE-SCLEROSIS - THE POTENTIAL ROLE OF PROTON MR SPECTROSCOPY IN DEFINING THE NATURE OF DISABILITY

PURPOSE: We determined the clinical utility of proton MR spectroscopy in defining the extent of disability in benign versus secondary-progre ssive multiple sclerosis (MS). METHODS: Thirty patients with clinicall y definite MS, including 16 patients with benign MS and 14 with second ary-progressive MS, and a group of 13 healthy volunteers were studied with combined stimulated-echo acquisition mode proton MR spectroscopy and MR imaging (all patients received contrast material). RESULTS: Acu te enhancing lesions of benign and secondary-progressive MS were chara cterized by a reduction in N-acetylaspartate (NAA)/choline and NAA/cre atine and an increase in inositol compounds/creatine as compared with normal white matter. Such variations were also detected in chronic une nhancing lesions in patients with secondary-progressive MS, although t hey were not found in chronic unenhancing lesions in patients with ben ign MS. Chronic lesions of the two forms of the disease have significa tive differences in NAA and inositol signals. CONCLUSION: Proton MR sp ectroscopy is able to show metabolic changes occurring in the white ma tter of patients with MS. Such changes differ according to the phase ( acute versus chronic) and the clinical form (benign versus secondary-p rogressive) of the disease.