3T MRI-SWI based volumetric analysis of the subthalamic and red nuclei in advanced Parkinson's disease

Parkinson's disease (PD) is a neurodegenerative disease mainly involving the dopaminergic neurons of the substantia nigra. The subthalamic nucleus (STN) also plays an important role in the disease process and now is an important target for the surgical management of the disease. However, not much is known about its morphology as the disease progresses. The aim of this study was to evaluate the volume of STN and red nucleus (RN) on 3T MRI SWI and its possible correlation with the disease in patients with advanced Parkinson's disease.

A total of 30 patients were enrolled. They were evaluated by analysis of symptomatology, UPDRS III, MOCA. Radiological evaluation included volumetric SWI images in 3T MRI. The volumes of the STN and RN were measured on SWI coronal images.

There were 24 (80%) males and 6 (20%) females. The mean volumes of STN and RN were 118.66 mm³ (80-170 mm³) and 379.66 mm³ (270-500 mm³). There was no significant difference between right and left STN volumes and RN volumes. There was a significant positive correlation between the disease duration and RN volumes (P=0.015) and STN volumes (in 6-13 years) (P=0.001). STN and RN volumes were negatively correlated with MOCA scores in males (P=0.008 and P=0.017), with no such correlation in females. In late-onset PD, there was a significant positive correlation between RN volume and UPDRS OFF and ON scores (P=0.028 and P=0.03).

STN volumes show a positive trend as the disease duration increases and cognition declines. RN volumes also increase as the disease progresses.