Dr. Theodore Rasmussen was a Canadian neurosurgeon, neurologist, and neuropathologist who primarily specialized in the treatment and histopathology of epilepsy. In addition to his eponym, "Rasmussen syndrome", a chronic form of encephalitis accompanied by epilepsy, his contributions included the refinement of neurosurgical techniques, thoroughly cataloguing outcomes following surgery for epilepsy, and cortical mapping studies conducted with Dr. Wilder Penfield.