Comparison of subthalamic nucleus borders determined by high-resolution MRI and microelectrode recording

Abstract

Background . Deep brain stimulation (DBS) of the subthalamic nucleus (STN) is an acknowledged efficient and safe method of treatment of advanced stages of Parkinson’s disease. The traditional way of intraoperative target verification is a combination of microelectrode recording (MER) and intraoperative macrostimulation. The appearance of high-field tomographs, new sequences, and methods of computer processing of the obtained images raises the question whether it’s necessary to use intraoperative verification of the target. Objective . The aim of the study was to analyze the comparability of 3T MRI data and microelectrode registration data in determining the boundaries of the subthalamic nucleus in patients with Parkinson's disease. Material and methods . 20 patients who have been undergone 3T MRI for preoperative planning for STN-DBS were included in the study. We determined the upper and lower boundaries of 40 subthalamic nuclei in high-resolution T2 and SWAN modes and compared these data with the data obtained during surgery using the MER. Results . The discrepancy between the MED and 3T MRI data when determining the upper STN border was 1.2 mm in SWAN mode and 1 mm in high-resolution T2 mode. The lower border of the subthalamic nucleus could be determined with an accuracy of 0.85 in SWAN mode and 0.75 mm in T2 mode. The groups didn’t have significant differences (Wilcoxon sign-rank test, p > 0.05). Conclusion . 3T MRI in high-resolution T2 and SWAN modes demonstrated high comparability with microelectrode data in determining the upper boundary, lower boundary and middle of the subthalamic nucleus, which makes it possible to use it as a method for direct STN imaging.