Targeting accuracy of robot-assisted deep brain stimulation surgery in childhood-onset dystonia: a single-center prospective cohort analysis of 45 consecutive cases

Abstract

Objective: Deep brain stimulation (DBS) is an established treatment for pediatric dystonia. The accuracy of electrode implantation is multifactorial and remains a challenge in this age group, mainly due to smaller anatomical targets in very young patients compared to adults, and also due to anatomical abnormalities frequently associated with some etiologies of dystonia. Data on the accuracy of robot-assisted DBS surgery in children are limited. The aim of the current paper was to assess the accuracy of robot-assisted implantation of DBS leads in a series of patients with childhood-onset dystonia.

Methods: Forty-five children with dystonia undergoing implantation of DBS leads under general anesthesia between 2017 and 2019 were included. Robot-assisted stereotactic implantation of the DBS leads was performed. The final position of the electrodes was verified with an intraoperative 3D scanner (O-arm). Coordinates of the planned electrode target and actual electrode position were obtained and compared, looking at the radial error, depth error, absolute error, and directional error, as well as the euclidean distance. Functional assessment data prospectively collected by a multidisciplinary pediatric complex motor disorders team were analyzed with regard to motor skills, individualized goal achievement, and patients' and caregivers' expectations.

Results: A total of 90 DBS electrodes were implanted and 48.5% of the patients were female. The mean age was 11.0 ± 0.6 years (range 3-18 years). All patients received bilateral DBS electrodes into the globus pallidus internus. The median absolute errors in x-, y-, and z-axes were 0.85 mm (range 0.00-3.25 mm), 0.75 mm (range 0.05-2.45 mm), and 0.75 mm (range 0.00-3.50 mm), respectively. The median euclidean distance from the target to the actual electrode position was 1.69 ± 0.92 mm, and the median radial error was 1.21 ± 0.79. The robot-assisted technique was easily integrated into the authors' surgical practice, improving accuracy and efficiency, and reducing surgical time significantly along the learning curve. No major perioperative complications occurred.

Conclusions: Robot-assisted stereotactic implantation of DBS electrodes in the pediatric age group is a safe and accurate surgical method. Greater accuracy was present in this cohort in comparison to previous studies in which conventional stereotactic frame-based techniques were used. Robotic DBS surgery and neuroradiological advances may result in further improvement in surgical targeting and, consequently, in better clinical outcome in the pediatric population.

Keywords: accuracy; deep brain stimulation; dystonia; functional neurosurgery; pediatric; robot-assisted surgery.