The contribution of cerebellar proton magnetic resonance spectroscopy in the differential diagnosis among parkinsonian syndromes

Abstract Introduction The in vivo differential diagnosis between idiopathic Parkinson's disease (PD) and atypical parkinsonian syndromes (PS), such as multiple system atrophy [MSA with a cerebellar (C) and parkinsonian (P) subtype] and progressive supranuclear palsy – Richardson's Syndrome (PSP-RS) is often challenging. Previous brain MR proton spectroscopy ( 1 H-MRS) studies showed biochemical alterations in PS, despite results are conflicting. Cerebellum plays a central role in motor control and its alterations has been already demonstrated in atypical PS. The main aim of this study was to evaluate diagnostic accuracy of cerebellar 1 H-MRS in the differential diagnosis between PD and atypical PS. Methods We obtained 1 H-MRS spectra from the left cerebellar hemisphere of 57 PS (21 PD, and 36 atypical PS) and 14 unaffected controls by using a 1.5 T GE scanner. N-acetyl-aspartate (NAA)/Creatine (Cr), choline-containing compounds (Cho)/Cr, myoinositol (mI)/Cr, and NAA/mI ratios were calculated. Results NAA/Cr and NAA/mI ratios were significantly lower (p  Conclusion Cerebellar biochemical alterations detected by using 1 H-MRS could represent an adjunctive diagnostic tool to improve the differential diagnosis of PS.