Postoperative Lead Movement after Deep Brain Stimulation Surgery and the Change of Stimulation Volume

Abstract

Introduction: Lead movement after deep brain stimulation may occur and influence the affected volume of stimulation. The aim of the study was to investigate differences in lead position between the day after surgery and approximately 1 month postoperatively and also simulate the electric field (EF) around the active contacts in order to investigate the impact of displacement on affected volume. Methods: Twenty-three patients with movement disorders underwent deep brain stimulation surgery (37 leads). Computed tomography at the 2 time points were co-fused respectively with the stereotactic images in Surgiplan. The coordinates (x, y, and z) of the lead tips were compared between the 2 dates. Eleven of these patients were selected for the EF simulation in Comsol Multiphysics. Postoperative changes of EF spread in the tissue due to conductivity changes in perielectrode space and due to displacement were evaluated by calculating the coverage coefficient and the Sørensen-Dice coefficient. Results: There was a significant displacement (mean ± SD) on the left lead: x (0.44 ± 0.72, p < 0.01), y (0.64 ± 0.54, p < 0.001), and z (0.62 ± 0.71, p < 0.001). On the right lead, corresponding values were: x (−0.11 ± 0.61, ns), y (0.71 ± 0.54, p < 0.001), and z (0.49 ± 0.81, p < 0.05). The anchoring technique was a statistically significant variable associated with displacement. No correlation was found between bilateral (n = 14) versus unilateral deep brain stimulation, gender (n = 17 male), age <60 years (n = 8), and calculated air volume. The simulated stimulation volume was reduced after 1 month because of the perielectrode space. When considering perielectrode space and displacement, the volumes calculated the day after surgery and approximately 1 month later were partly overlapped. Conclusion: The left lead tip displayed a tendency to move lateral, anterior, and inferior and the right a tendency to move anterior and inferior. The anchoring technique was associated to displacement. New brain territory was affected due to the displacement despite considering the reduced stimulated volume after 1 month. Postoperative changes in perielectrode space and small lead movements are reasons for delaying programming to 4 weeks following surgery.

Deep Brain Stimulation: Emerging Tools for Simulation, Data Analysis, and Visualization

“…During surgery, a small burr hole (about 14 mm in diameter) is created for insertion of the lead at the planned entry point. Immediately after opening of the dura, Tisseel glue (Baxter Medical AB, Sweden) is applied to avoid cerebrospinal fluid (CSF) leak and air entry and can thus help reduce the brain shift ( Göransson et al, 2021 ). During surgery, various intraoperative techniques can help guide the surgeon to the pre-planned target.…”

“…Quantitative measures of wrist movements with accelerometers ( Figure 5A ) were automatically linked to intraoperative test stimulations to find a threshold with the clinical effect ( Hemm et al, 2016 ). Patient-specific electric field studies have been applied for both movement disorders such as PD and ET ( Åström et al, 2010 ; Alonso et al, 2018 ; Göransson et al, 2021 ; Stenmark Persson et al, 2021 ) and in relation to psychiatric indication such as GTS ( Wårdell et al, 2015 ; Akbarian-Tefaghi et al, 2017 ) and OCD ( Naesstrom et al, 2021 ).…”

Deep brain stimulation: Challenges at the tissue‐electrode interface and current solutions

“… 27 . Other causes for postoperative displacement include technical errors, failure of lead fixation, twiddler syndrome, and pneumocephalus 28 . The STN is approximately 8 mm long by 6 mm wide with three regions.…”

“…These changes, along with shifting of the brain over time, contribute to the electrode migration.. 27 Other causes for postoperative displacement include technical errors, failure of lead fixation, twiddler syndrome, and pneumocephalus. 28 The STN is approximately 8 mm long by 6 mm wide with three regions. Displacement of electrodes by even a few millimeters could migrate the lead off its intended target.…”

DBSim and ELMA - Freeware for Simulations of Deep Brain Stimulation

“…Patient-specific FEM simulations require tissue-specific electric conductivity assignment [26]. We have previously presented a software package for tissue classification and conductivity assignment named ELMA [27] (Figure 1) which we have used in our previous studies [21,23,[28][29][30]. ELMA, however, only provides the conductivity classification and requires other, often expensive, software for the patientspecific simulations.…”