Factors Affecting Stereotactic Accuracy in Image-Guided Deep Brain Stimulator Electrode Placement

Abstract

Background/Aims: Intraoperative imaging allows near-real-time assessment of stereotactic accuracy during implantation of deep brain stimulation (DBS) electrodes. Such technology can be used to examine factors impacting stereotactic error. Methods: Intraoperative CT imaging was reviewed in patients undergoing DBS placement at Oregon Health and Sciences University. Coordinates of the target electrode were compared to the operative plan to characterize the magnitude and direction of stereotactic error with respect to side of implantation, target, and electrode approach angles. Results: One hundred sixty-nine leads in 94 patients were examined. Targets were GPi (n = 86), STN (n = 31), and Vim (n = 52). The average Euclidean error was 1.63 mm (SD 0.87). The error magnitude was higher for Vim (1.95 mm) than for GPi (1.44 mm), while STN (1.65 mm) did not differ from either Vim or GPi (ANOVA: F = 6.15, p = 0.003). Electrodes targeting Vim and STN were significantly more likely to deviate medially compared to those targeting GPi (ANOVA: F = 9.13, p < 0.001). The coronal approach angle affected the error when targeting Vim (ρ = 0.338, p = 0.01). These findings were confirmed during multivariate analyses. Conclusions: This study shows a significant effect of target on the accuracy of electrode placement for DBS. Targeting Vim results in a greater Euclidean error and a greater medial deviation off target. These systematic deviations should be taken into account during electrode implantation.

Comparison of Awake and Asleep Deep Brain Stimulation for Parkinson’s Disease: A Detailed Analysis Through Literature Review

“…The intended targets were GPi ( n = 86), STN ( n = 31), and Vim ( n = 52). The results indicated that the average Euclidean error was 1.63 mm (SD = 0.87) . However, the error magnitude was higher for Vim (1.95 mm, greater Euclidean error and greater medial deviation off target) than for GPi (1.44 mm), while STN (1.65 mm) did not differ from either Vim or GPi (ANOVA: F = 6.15, p = 0.003) .…”

“…The main advantage of placing DBS electrodes using iMRI is the ability to visualize the intended target and this allows for precise implantation and adjustment of electrode trajectories before final placement . One study evaluated the effect of target selection on the accuracy of electrode placement in asleep DBS for the treatment of movement disorders . The study examined 169 leads in 94 patients using intraoperative imaging.…”

Bilateral Subthalamic Nucleus Deep Brain Stimulation under General Anesthesia: Literature Review and Single Center Experience

“…In a large-scale study of DBS patients who underwent surgery using iCT, there were greater Euclidean error and greater medial deviation in the trajectory targeting Vim. The authors found that there are systematic tendencies in stereotactic error that differ with respect to the structure targeted [70]. In the study analyzing stereotactic accuracy of iMRI, the DBS lead placement using iMRI guidance showed a radial targeting error of 0.6-1.2 mm, while the error using iCT was 0.8-1.24 mm [22,25,27,28,31,37,71].…”

Frameless stereotactic brain biopsy: A prospective study on robot‐assisted brain biopsies performed on 32 patients by using the RONNA G4 system

“…Linear regression done on our data has shown statistical significance between the TPE and the trajectory angle on the bone surface, and the EPE and the trajectory angle on the bone surface. Previous research just stated that the direction of the trajectory or the angle of the trajectory had a great influence on the accuracy of the procedure, without giving an adequate description of the methodology and measurements 3,38–41 . We noticed that a larger size angle on the bone caused greater displacement of the drill bit due to a greater magnitude of shear force, which increased the EPE.…”

“…Bleeding originating from superficial vessels may be the cause of EPE and that originating from vessels on the trajectory path and on the biopsy site may be the cause of TPE. Several papers report the correlation between the EPE or TPE and the angle of trajectory on the skull; however, the angle of the trajectory is defined as the deviation of the angle on the coronal or the sagittal plane 40–42 . We made a multiplanar reconstruction through the entry point on the skull and measured the largest deviation of the angle (Figure 3).…”