Abstracts

Rationale: Robotic trajectory guidance devices for stereotactic neurosurgery have become common-place for deep brain stimulation, brain biopsy and stereoelectroencephalography (SEEG). Despite these devices having associated learning curves and significant cost implications, there is no level 1 evidence showing improved operative outcomes or safety. Methods: Thirty-two patients from a tertiary referral epilepsy center consented for inclusion in the study comparing conventional frameless SEEG electrode insertion utilizing the precision aiming device (PAD) versus the iSYS1 robotic trajectory guidance system. The primary outcome measure was operative time (minutes) for insertion of the cranial bolt. Secondary outcomes were the accuracy of implantation (entry point, angle and target point), postoperative haemorrhage rate, infection rate and postoperative neurological deficit rate. Randomization was by sealed envelope. The patients and trial statistician were blinded to the intervention arm. The surgical team could not be blinded. The study was approved by the regional ethics committee, REC reference: 17/EE/0016. The trial protocol was prospectively registered and published: ISRCTN172090256. Results: The trial completed with 32 patients recruited and analyzed for the primary and secondary outcome measures. The iSYS1 robotic trajectory guidance arm resulted in a significantly shorter operative time for intracranial bolt insertion, 7.1±3.9 versus 10.1±6.3 (mean±SD), p<0.0001. The PAD resulted in a comparatively better target point accuracy of 1.4±1.0 versus 1.9±1.1 (mean±SD), p<0.004. There was no statistically significant difference in any of the other outcome measures. Three patients had small asymptomatic hemorrhages noted on post-operative imaging that did not require any intervention; two of these were in the PAD arm. Conclusions: Operative time for individual SEEG bolt insertion was significantly shorter with the iSYS1 robotic trajectory guidance system compared to the PAD. Target point accuracy was significantly better with the PAD. There was no significant difference in the entry point accuracy, overall operative time, post-operative neurological deficit, infection or intracranial hemorrhage rates. Funding: Wellcome Trust (Grant number: WT106882)