Rafał Rola, Marcin Tutaj, Henryk Koziara, Dariusz Koziorowski, Bogdan Brodacki, Michał Karliński, Tomasz Tykocki, Bartosz Krolicki and Tomasz Mandat
Background and purpose: Target point identification based solely on MRI and CT of subthalamic nucleus (STN) in deep brain stimulation procedures (DBS) for Parkinson’s disease (PD) might have suboptimal clinical effects. The authors analyse alterations of permanent electrode location depending on neurophysiological evaluation compared to an anatomically based calculated target. Materials and methods: The group comprised 66 patients (32 females and 34 males) aged 57.6 (38–76) years, in whom 131 electrodes were implanted. The patients were qualified for the surgery according to the CAPSIT-PD criteria. STN was identified using the direct and indirect methods, based on 1.5 T MRI and CT. The surgery was performed under local anesthesia. Two to 5 microelectrodes were used for microrecording and macrostimulation. Results: Anterior (49.2%), central (35.6%) and lateral (13.6%) trajectories were most frequently used for permanent electrode placement. The electrode was most frequently placed at a depth of +2/+3 (58.3%) or +1 and +5 mm (36.4%) with regard to the planned target point. Differences in selecting the trajectory and depth of the final electrode position were statistically significant (p<0.05). Conclusion: DBS implantation based only on anatomical identification of STN can lead to suboptimal results. Additional application of intrasurgical neurophysiological analysis may increase the effectiveness of the STN DBS therapy for PD.