Anatomic hemispherectomy: historical perspective.

The history of surgical treatment for hemispheric epilepsy is rich with colorful twists and turns. The authors trace the evolution of the surgical treatment of hemispheric epilepsy from radical anatomic resections to current less invasive disconnection procedures. Anatomic hemispherectomy (AH) was first described by Dandy in 1928 as a treatment for gliomas. The first report of this technique to control seizures was by McKenzie in 1938. AH gained wide popularity but began to fall out of favor after the description of superficial cerebral hemosiderosis in 1966. To reduce the morbidity and mortality associated with AH, Rasmussen introduced functional hemispherectomy in 1974. The technique of hemispherotomy was introduced in the 1990 s to minimize the extent of brain removal while maximizing the white matter disconnections. Thus, surgery for hemispheric epilepsy has undergone dramatic transformation since the technique was first introduced. Less invasive techniques have been developed to reduce surgical morbidity. Although optimal seizure control is best achieved with radical AH, the newer less invasive disconnection techniques appear to achieve near-comparable postoperative seizure control with a significantly lower rate of complications.