Cerebral hemispherectomy: sensory scores before and after intensive mobility training.

Purpose: It is unclear whether sensory modalities can be modified by rehabilitation and if sensory functions vary on the affected side many years after cerebral hemispherectomy. This pilot, proof-of-concept study assessed light touch and proprioception before and after 10 days of intensive mobility training in individuals after hemispherectomy.

Methods: Light touch and proprioception of the upper and lower extremity was measured using the Fugl-Meyer sensory subtest on the paretic side in 18 individuals with hemispherectomy before and after mobility training. Sensory scores and differences related to mobility training were compared with clinical variables.

Results: Patients were 7.1±5.7 years from time of surgery to sensory assessment and mobility training. Light touch scores were 81±22% and proprioception values were 64±23% of normal (p=0.0022). Light touch did not correlate with proprioception scores, and differences comparing after with before mobility training did not correlate. In multivariate analysis, younger age at seizure onset correlated with better light touch scores, and older age at onset correlated with improvements in light touch scores with mobility training. By comparison, proprioception scores were better in individuals with perinatal infarcts compared with Rasmussen encephalitis and Sturge-Weber. Post-training, proprioception scores were better in Sturge-Weber cases.

Conclusion: Light touch was less affected than proprioception on the paretic side after cerebral hemispherectomy. Improvements with mobility training correlated with older age at seizure onset and etiology. These findings suggest that many years after epilepsy surgery sensory functions are not static supporting the notion of existing developmental neuroplasticity of the remaining cerebral cortex along with brain stem and spinal cord pathways.