Abstract
INTRODUCTION: Cardiac sympathetic denervation is specific to Lewy body disease (LBD). In Parkinson's disease (PD), sympathetic denervation in the major salivary glands (parotid glands [PG] and submandibular glands [SMG]) has been demonstrated by (123)I-metaiodobenzylguanidine (MIBG) scintigraphy. We compared sympathetic denervation in the MSG between PD, dementia with Lewy bodies (DLB), and progressive supranuclear palsy (PSP). METHODS: We recruited 81 patients with PD, 12 with DLB, 13 with PSP and 25 with control subjects. We evaluated MIBG uptake in the major salivary glands and heart using a quantitative semi-automatic method. We compared MIBG uptake between PD, DLB, and PSP patients and controls, and we evaluated disease sensitivity and specificity. We compared olfactory function with MIBG uptake between PD and PSP patients. RESULTS: MIBG uptake in the PG and SMG in the delayed phase was significantly lower in PD and DLB patients than in PSP patients and controls. Conversely, MIBG uptake in the major salivary glands and heart was comparable between PD and DLB. Between LBD and non-LBD, MIBG uptake showed 56-100 % specificity in the PG, while it had 55.6-87.5 % sensitivity in the SMG. Between PD and PSP, MIBG uptake in the PG and SMG had higher disease specificity than olfactory function, while the sensitivity of SMG MIBG uptake was comparable to olfactory function. CONCLUSION: PD and DLB patients showed lower MIBG uptake in the major salivary glands than PSP patients, especially in the delayed phase. MIBG uptake in the major salivary glands may differentiate PD from hyposmic PSP.