STN and GPi-Deep Brain Stimulation for Primary Cervical Dystonia

OBJECTIVE: To evaluate the safety and efficiency of deep brain stimulation (DBS) in the treatment of primary cervical dystonia (CD) and to compare the difference between the STN (subthalamic nucleus)-DBS and GPi (Globus Pallidus internus)-DBS. STUDY DESIGN: Experimental study. Place and Duration of the Study: Department of Neurosurgery, Beijing Tiantan Hospital, Capital Medical University, Beijing, China, from January 2012 to December 2021. METHODOLOGY: This study analysed the effects of DBS on 34 patients with primary cervical dystonia (CD) based on the Toronto Western Spasmodic Torticollis Rating Scale (TWSTRS). It included 15 STN-DBS and 19 GPi-DBS cases, with TWSTRS scores collected at baseline and the final follow-up. Stimulation parameters and adverse events were also recorded. RESULTS: The mean follow-up time was 42.77 ± 27.46 months. A significant improvement in TWSTRS total scores was observed in all patients (p <0.001), with no significant difference between STN-DBS and GPi-DBS groups (p = 0.481). The amplitude of stimulation in the GPi group was found to be higher than that in the STN group (p <0.001). Adverse events included one case of electrode breakage in the STN-DBS group, mild dyskinesias in 14 patients (twelve from the STN-DBS group and two from the GPi-DBS group), and other stimulation-related complications in four patients (one from the STN-DBS group and three from the GPi-DBS group). All stimulation-related complications were manageable with parameter adjustments. CONCLUSION: DBS can significantly improve the symptoms of primary CD patients, with no significant difference in outcomes between STN-DBS and GPi-DBS. It has a good long-term therapeutic effect and surgical safety. KEY WORDS: Cervical dystonia, Deep brain stimulation, Globus pallidus internus, Subthalamic nucleus.