Hemispherotomy or lobectomy? The role of presurgical neuroimaging in a young case of a large porencephalic cyst with intractable epilepsy.

A young patient with a large left hemisphere porencephalic cyst underwent neuroimaging investigation (functional magnetic resonance imaging (fMRI), EEG-fMRI, DTI tractography) during presurgical evaluation for intractable epilepsy. The functional workup showed that (a) the healthy hemisphere had undertaken language processing, primary and secondary sensory functions of bilateral upper and lower extremities, and bilateral feet motion, and (b) the porencephalic hemisphere had retained contralateral arm and shoulder motion. EEG-fMRI localized the epileptogenic area occipitally. Tractography anatomically supported the above. Neuroimaging tailored surgery into selective lobectomy, thereby preserving all sensorimotor functionality and strongly supporting its use for presurgical evaluation of patients with large hemispheric lesions.