Introduction: Partial preservation of sensory and motor functions in the contralateral extremities after hemispherectomy is likely secondary to cortical reorganization of the remaining hemisphere and can be improved by rehabilitation. This study aims to investigate behavioral and structural cerebral cortical changes that may occur after a 2-week novel robotic rehabilitation program in children with prior anatomic hemispherectomy.Methods: Five patients with prior anatomic hemispherectomy (average age 10.8 years; all female) participated in a 2-week novel robotic rehabilitation program. Pre-and post-treatment (2 time points) highresolution structural 3D FSPGR (fast spoiled gradient echo) magnetic resonance images were analyzed to measure cortical thickness and gray matter volume using a locally designed image processing pipeline.Results: Four of the ve patients showed improvement in the Fugl-Meyer score (average increase 2.5 + 2.1 SD. Individual analyses identi ed small increases in gray matter volume near the hand knob area of the primary cortex in three of the ve patients. Group analyses identi ed an increase in cortical thickness near the hand knob area of the primary motor cortex, in addition to other sensorimotor regions.Conclusion: This small pilot study demonstrates that potentially rehabilitation-associated cortical changes can be identi ed with MRI in hemispherectomy patients.