Ultrasound Changes of the Vagus Nerve in Patients With Parkinsonism

The patients and controls will be scanned at the Neurophysiology unit of the Department of Neurology, Neurology, psychiatry and Neurosurgery hospital, Assiut university hospital. The acquisition of ultrasound images was performed using a Philips HD11XE imaging system with an L12-8 linear array probe. Cross-sectional area (CSA) of the right and left Vagus nerves in each subject, perimeter, echogenicity, and fascicular structure will be assessed and measured by tracing the nerve just inside its hyperechoic rim. The nerve will be seen on ultrasound B-mode near the bifurcation of the carotid artery, dorsal to the internal and common carotid arteries, as a structure that is hypoechogenic in the centre and more hyperechogenic on the periphery (24, 25). Both the carotid artery and the internal jugular vein served as anatomical landmarks (25). Two separate CSA measurements, with the probe repositioned for each measurement, will be taken and they will be averaged.