Electronic Thesis and Dissertation Repository


Master of Science


Medical Biophysics


Dr. Ravi Menon


Hemiplegic cerebral palsy is characterized by unilateral upper limb impairment and patients often compensate by performing most tasks with their unaffected arm. Constraint-induced movement therapy (CIMT) directly combats this learned non-use by casting the unaffected arm and forcing the patient to repetitively practice skills with the hemiplegic limb. Subjects with hemiplegic cerebral palsy were recruited from Holland Bloorview Kids Rehabilitation Hospital, Thames Valley Children’s Centre and McMaster Children’s Hospital. MRI acquisitions and clinical evaluations were collected at baseline, 1 and 6-months later. The case group participated in a CIMT camp after baseline evaluations and was compared to an untreated control group. Resting state functional magnetic resonance imaging (fMRI) and diffusion tensor imaging (DTI) acquisitions quantify global network organization and neural integrity, respectively, and found alterations in multiple resting state network connectivity patterns and significantly different fractional anisotropy and mean diffusivity in the affected corticospinal tract. Asymmetric baseline sensorimotor network organization was predictive of a positive and continuous functional response to CIMT. Clinically correlated network reorganization provides further evidence of neuroplastic mechanisms related to CIMT.