A comparison of indirect and direct targeted STN DBS in the treatment of Parkinson's disease-surgical method and clinical outcome over 15-year timespan.

BACKGROUND: Deep brain stimulation (DBS) in the subthalamic nucleus (STN) is used in advanced Parkinson's disease (PD) for reducing motor fluctuations and the side effects of antiparkinsonian medication (APM). The development of neuroimaging has enabled the direct targeting of the STN. The aim of this study is to evaluate the outcome in patients with PD using STN DBS when changing from atlas-based indirect targeting method (iTM) to direct MRI-based targeting (dTM) assuming dTM is superior. METHODS: Twenty-five consecutive PD patients underwent dTM STN DBS surgery from 2014 to 2017 with follow-up for 1 year. The neuroimaging, surgical method, outcome in Unified Parkinson's Disease Rating Scale (UPDRS) scores, and reduction of APM are described and compared with the results of an earlier iTM STN DBS study. RESULTS: Twelve months after a dTM STN DBS, significant improvement (p < 0.001) was seen in six out of seven parameters of UPDRS when patients had medication (medON) and stimulation (stimON). The activities of daily living (UPDRSII) and motor scores (UPDRSIII) improved by 41% and 62%, respectively. Dyskinesias and fluctuations were both reduced by 81%. In dTM STN DBS group, the levodopa equivalent dose (LED) and the total daily levodopa equivalent dose (LEDD) were significantly decreased by 62% and 55%, respectively, compared with the baseline (p < 0.001). Five patients (20%) were without levodopa medication 12 months after the operation. CONCLUSIONS: The development of surgical technique based on advanced neuroimaging has improved the outcome of PD STN DBS.

Stereotactic operations using the o-arm.

BACKGROUND: In stereotactic operations, intraoperative imaging is crucial in several stages of the procedure. The aim was to utilize the O-arm intraoperatively for (1) planning the trajectories of stereotactic instruments, (2) calculating the coordinates of the targets, (3) identification of normal intracranial structures, (4) verification of the trajectories of the stereotactic instruments, and (5) visualization of intracranial hematoma. This is the first study using the O-arm for calculations of the target coordinates in frame-based stereotaxy. METHODS: Utilization of the O-arm as a full-scale intraoperative imaging system in stereotactic surgery required a new concept. The concept consists of the O-arm as an intraoperative imaging system and the Leksell stereotactic system with a modified CT coordinate indicator box, with the idea to widen limited imaging volume. The accuracy and feasibility of the concept were studied. RESULTS: The use of O-arm imaging was found to be clinically feasible, enabling the achievement of adequate technical accuracy for stereotactic operations with submillimeter errors in the calculation of target coordinates, and for multiple intraoperative control images when required. CONCLUSIONS: The O-arm could be used alone, with high accuracy, as an intraoperative imaging system for planning and controlling in stereotactic operations. In addition, it can be used to exclude serious complications, especially intracerebral hematoma.