Beyond the Globus Pallidus: A Systematic Review of Deep Brain Stimulation of Extrapallidal Targets for Pediatric...

Deep brain stimulation (DBS) is increasingly prevalent in the management of pediatric movement disorders. The globus pallidus interna (GPi) is the most common target; however, anatomical factors (eg, structural damage) may preclude GPi stimulation. Given that movement disorders represent network-based disorders, there may be additional targets for stimulation. We performed a systematic review to investigate the efficacy of extrapallidal targets in pediatric movement disorders.

We performed a systematic electronic literature search. Data were extracted to include pediatric patients (aged 0-18 years) with movement disorders who underwent extrapallidal DBS. We excluded adults and those treated for psychiatric indications, including Tourette syndrome.

Overall, 112 participants were identified from 48 references. Dystonia was the most commonly reported movement disorder treated with DBS targeting extrapallidal structures, followed by tremor, juvenile parkinsonism, and chorea. The subthalamic nucleus was the most frequent extrapallidal DBS target for dystonia, with reported improvement observed mostly in dystonia of genetic nondegenerative cases. The ventral intermediate nucleus of the thalamus was the second most implanted target in patients with dystonia and tremor. Other targets, including other thalamic nuclei, were often combined with GPi stimulation in patients with dystonia.

Alternative targets beyond the GPi, or in combination with pallidal stimulation, hold promise as potentially efficacious and safe for DBS as the treatment of pediatric movement disorders, particularly if limited benefit, contraindications, or complications exist in GPi stimulation. Future studies are required to further validate their effectiveness and safety.