TOPSS: TOlerability of transcranial direct current stimulation in Pediatric Stroke Survivors.

Background: Transcranial direct current stimulation is a non-invasive neuromodulation technique with emerging therapeutic potential in neurodevelopmental conditions. While childhood-onset stroke survivors frequently experience long-term motor impairment, there are very few studies examining the safety and feasibility of transcranial direct current stimulation in this population. Objective: To evaluate the safety, feasibility, and tolerability of bihemispheric transcranial direct current stimulation paired with occupational therapy in children and adolescents with chronic hemiparesis following childhood-onset arterial ischemic stroke or intracranial hemorrhage. Methods: In this single-arm, open-label pilot study, five participants aged 6-19 years of age received five daily sessions of transcranial direct current stimulation (sham on day 1, then 0.5-1.5 mA) during structured occupational therapy. Safety and tolerability were assessed through side effect questionnaires, pre-and post-stimulation vital signs, and study completion rates. Secondary exploratory outcomes included arm function measures (Fugl-Meyer Assessment of Upper Extremity, perceived performance and satisfaction) (Canadian Occupational Performance Measure), and gross manual dexterity (Box and Blocks Test). Results: All participants completed the study with no major adverse events. Mild, self-limited itching or tingling occurred in 40% of sessions and did not limit participation. Four of five participants demonstrated clinically significant improvement on the Fugl-Meyer Assessment of the Upper Extremity at 3-month follow up. Improvements were also observed in the Canadian Occupational Performance Measure and satisfaction scores. One participant with a prior craniectomy tolerated stimulation without adverse events. Conclusion: tDCS was well-tolerated in children and adolescents with chronic hemiparesis from childhood-onset stroke. These findings support the feasibility of transcranial direct current stimulation in this population and provide early-stage evidence to guide future randomized controlled trials exploring therapeutic applications of neuromodulation in childhood-onset stroke recovery. Clinical trial registration: https://clinicaltrials.gov/study/NCT05812794?term=AREA%5BBasicSearch%5D(pediatric%20stroke)&rank=10, ID: NCT05812794.