Multimodal Localization of Electrodes in Deep Brain Stimulation: Comparison of Stereotactic CT and MRI with Teleradiography

Abstract

Objective: In cross-sectional imaging, like CT or MRI, electrodes for deep brain stimulation are visualized by an artifact, which can differ from the real physical size of the electrode and even have an asymmetric appearance on MRI. The accuracy of such artifact-based estimation of the real position of the electrode using CT or MRI is investigated here. Stereotactic teleradiography was used as the gold standard. Methods: Twenty-three patients with implanted electrodes in the subthalamic nucleus (DBS type 3389; Medtronic, Minneapolis, Minn., USA) were included in a retrospective study on multimodal estimation of electrode position by 2 raters. Short spoiled gradient echo MRI (n = 10) and multi-row CT (n = 13) data were compared with teleradiography. Results: Mean radial differences between CT and X-ray for both raters were 0.6 ± 0.2 and 0.7 ± 0.3 mm, with maximum values of 1.0 and 1.2 mm, respectively. Both raters showed quite similar assessments in their ratings. Mean radial differences between MRI and X-ray were 1.2 ± 0.4 and 1.1 ± 0.4 mm, with maximum values of 1.7 and 2.2 mm. Concordance of the assessment was lower compared to CT. Conclusion: Spoiled gradient echo MR imaging cannot be recommended for visual localization of the quadripolar macroelectrode type 3389 from Medtronic. In contrast, CT imaging in absolute terms and with quite similar assessments by both raters is intra- and postoperatively a satisfactory alternative to teleradiography.

Non-motor outcomes of subthalamic stimulation in Parkinson's disease depend on location of active contacts

“…We screened 88 consecutive patients from our database and included 65 patients with all necessary valid baseline and 6 months follow-up assessments in the analysis. Of these, fourteen patients from Cologne were excluded as postoperative CT imaging was not available because the final position of stimulation leads as per clinical routine was confirmed with intraoperative teleradiography before August 2012 [26]. One patient was excluded due to a clinically relevant lateral deviation of the stimulation lead.…”

Review on Factors Affecting Targeting Accuracy of Deep Brain Stimulation Electrode Implantation between 2001 and 2015

“…The fused image inherits MRI's high anatomical resolution and CT's high geometric accuracy, but this method increases technical and procedural complexity and may introduce image fusion error. Advanced image fusion algorithms are needed to minimize this error [56,57,59,60]. Another effective strategy is to develop MRI-compatible devices or high-resolution MRI systems, which has become a trend in recent years [12,13,15,25,35,41,54,61,62].…”

Determining the orientation angle of directional leads for deep brain stimulation using computed tomography and digital x‐ray imaging: A phantom study

“…To facilitate determination of the lead angle, a passive directional marker is added close to the electrodes by the manufacturers. This directional marker can be imaged with computed tomography (CT) and stereoscopic radiography, two standard imaging procedures used during and after stereotactic surgery to aid probe placement and to determine anatomical placement of the electrodes . Since the diameter of DBS leads is only 1.3 mm, the detailed structure of directional markers can hardly be visualized on CT‐images due to limitations in spatial resolution and disturbing image artifacts around the lead .…”

“…This directional marker can be imaged with computed tomography (CT) and stereoscopic radiography, two standard imaging procedures used during and after stereotactic surgery to aid probe placement and to determine anatomical placement of the electrodes. [11][12][13][14] Since the diameter of DBS leads is only 1.3 mm, the detailed structure of directional markers can hardly be visualized on CT-images due to limitations in spatial resolution and disturbing image artifacts around the lead. 15 Therefore, we followed an approach similar to Motevakel and Medvedev 16 and used the artifacts themselves to obtain indications on the lead orientation.…”