Olfactory Bulb Volume, Olfactory Sulcus Depth in Parkinson's Disease, Atypical Parkinsonism
Debayan Dutta, Karthik Kulanthaivelu, Vikram V. Holla, Nitish Kamble, Ravi Yadav, Pramod Kumar Pal, Rohan Mahale
Abstract
Background: About 70-90% of Parkinson's disease (PD) patients have olfactory deficits which is considered as pre-motor symptom of PD. Lewy bodies have been demonstrated in the olfactory bulb (OB) in PD. Objective: To assess the OB volume (OBV), olfactory sulcus depth (OSD) in PD and compare with progressive supranuclear palsy (PSP), multiple system atrophy (MSA) and vascular parkinsonism (VP) patients and determine the cut-off volume of OB that will aid in the diagnosis of PD. Methods: This was a cross-sectional, hospital based, single-center study. Forty PD, 20 PSP, 10 MSA, 10 VP patients and 30 controls were recruited. OBV and OSD was assessed using 3-T magnetic resonance imaging (MRI) brain. Olfaction was tested using Indian Smell Identification test (INSIT). Results: = 0.41) with no difference. The mean total OBV was significantly lower in PD as compared to that of PSP, MSA and VP patients. There was no difference in the OSD among the groups. The total OBV in PD had no association with age at onset, duration of disease, dopaminergic drugs dosage, motor and non-motor symptoms severity but had positive correlation with cognitive scores. Conclusion: OBV is reduced in PD patients as compared to PSP, MSA, VP patients and controls. OBV estimation by MRI adds to the armamentarium in the diagnosis of PD.