Long-Term Outcomes of Deep Brain Stimulation for Pediatric Dystonia

Abstract

Background Deep brain stimulation (DBS) has been utilized for over two decades to treat medication refractory dystonia in children. Short-term benefit has been demonstrated for inherited, isolated and idiopathic cases, with less efficacy in heredodegenerative and acquired dystonias. The ongoing publication of long-term outcomes warrants a critical assessment of available information as pediatric patients are expected to live most of their lives with these implants. Summary We performed a review of the literature for data describing motor and neuropsychiatric outcomes, in addition to complications, five or more years after DBS placement in patients undergoing DBS surgery for dystonia at an age younger than 21. We identified 20 articles including individual data on long-term motor outcomes after DBS for a total of 78 patients. In addition, we found five articles reporting long-term outcomes after DBS in nine patients with status dystonicus. The majority of patients were implanted within the globus pallidus internus, with only a few cases targeting the subthalamic nucleus and ventrolateral posterior nucleus of the thalamus. The average follow-up was 8.5 years, with a range up to 22 years. Long-term outcomes showed a sustained motor benefit, with median Burke-Fahn-Marsden dystonia rating score improvement ranging from 2.5% to 93.2% in different dystonia subtypes. Patients with inherited, isolated and idiopathic dystonias had greater improvement than those with heredodegenerative and acquired dystonias. Sustained improvements in quality of life were also reported, without the development of significant cognitive or psychiatric co-morbidities. Late adverse events tended to be hardware-related, with minimal stimulation-induced effects. Key Messages While data regarding long-term outcomes is somewhat limited, particularly with regards to neuropsychiatric outcomes and adverse events, improvement in motor outcomes appear to be preserved more than 5 years after DBS placement.

Deep Brain Stimulation for Refractory Status Dystonicus in Children: Multicenter Case Series and Systematic Review

“…Our study confirms that DBS targets for SD are not particularly different from those for elective DBS insertion for severe, but stable, dystonia 69–71 . This is not surprising given that dystonia presents with a continuum of severity, with SD being the severe and life‐threatening form.…”

“…Our study confirms that DBS targets for SD are not particularly different from those for elective DBS insertion for severe, but stable, dystonia. [69][70][71] This is not surprising given that dystonia presents with a continuum of severity, with SD being the severe and life-threatening form. Based on our results, we recommend primarily targeting the posterior ventrolateral GPi, but we note that there are cases where other targets might be considered (specifically, the STN).…”

Neurosurgical and pharmacological management of dystonia

“…Other hardware related adverse events include infection of the skin or implant, malfunction related to internal pulse generator erosion of failure, and electrode or extension wire damage[ 68 ]. Battery life is an additional challenge of DBS, presenting with the most difficulty in pediatric cases where many battery changes are required over the course of their life and thus a higher risk of surgical complications is apparent[ 69 , 70 ]. The advent of rechargeable devices has somewhat alleviated this problem in both pediatric and adult populations, demonstrating lower complication rates and higher patient satisfaction[ 71 , 72 ].…”

“…In pediatric patients, benefits following DBS have been reported 5 or more years following implantation[ 69 ]. The anatomical changes depending on the age of the child also pose difficulties as the anatomical structure is growing rapidly and altering the surgical target site.…”

Deep Brain Stimulation in a Patient with TSPOAP1‐Biallelic Variant of Autosomal‐Recessive Dystonia

“…3 Because drug therapies are often limited, deep brain stimulation (DBS) has been used with varying success in different forms of dystonia. 4,5 In October 2021, we examined an 11-year-old girl with dystonia of yet-unknown origin. Prenatal period and early childhood were unobtrusive.…”