Evaluation of White Matter and Cerebellum Structures of Essential Tremor and Parkinson's Patients by Diffusion Tensor Imaging and Volbrain Method

Essential tremor (ET) and Parkinson's disease (PD) are the two most commonly encountered tremor disorders in movement disorders. Diffusion tensor imaging (DTI) is one of the best in vivo ways of mapping white matter pathways in the human brain. The aim of our study was to investigate diffusion variables and cerebellum volume in ET and PD using parcellation methods. Our study included 20 ET, 20 PD and 20 healthy controls. Fraction Anisotropy (FA) and Mean Diffusivity (MD) values were obtained with DTI, while the volume of each lobe of the cerebellum was obtained with T1 images. One-way ANOVA was used for intergroup analysis and Scheffe test was used for post-hoc analysis. Significant differences were found in the diffusion values of the pedunculus cerebellaris, fornix stria, superior longitudinal fasciculus, sagittal stratum, cerebral pedunculus, tapatum and thalamus of ET and PD. Lobule V, Lobule IX, Lobule X volumes of the cerebellum showed significant differences between the groups. Stria thermialis shows involvement of mesolimbic dopaminergic system in PD and it is thought that disruption of strial networks leads to changes in the activity of cerebellar networks and reveals the role of the cerebellum in tremor. It is obvious that cerebellar thalamocortical pathways are affected in Parkinson's disease. In Parkinson's disease, patients should be evaluated for visual processing, conceptualisation, postural instability and gait disturbance to clarify the diagnosis or to differentiate from essential tremor.