Transcranial magnetic stimulation mapping of motor and language systems in populations for which fMRI is not feasible

Brisbane Convention & Exhibition Centre 

Accurate presurgical mapping of motor, speech, and language cortices, while crucial for neurosurgical planning and minimizing post-operative functional deficits, is challenging in young children with neurological disease. In such children, both invasive (cortical stimulation mapping) and non-invasive functional mapping imaging methods (MEG, fMRI) have limited success, often leading to delayed surgery or adverse post-surgical outcomes. Transcranial magnetic stimulation (TMS) is a safe, reliable, and effective tool to map eloquent cortices in young children. In this talk I will review the experience of our and other centres with regards to the clinical utility of TMS in young children with refractory epilepsy or brain tumors. Using TMS, both normal motor, speech, and language developmental patterns and apparent disease induced reorganization have been demonstrated in this young cohort. The successful localization of motor, speech, and language cortices in young children improves the understanding of the risk-benefit ratio prior to surgery and facilitates surgical planning aimed at preserving motor, speech, and language functions.