ABSTRACT
Anterior temporal lobectomy (ATL) is the most commonly used and the most successful surgical treatment for intractable epilepsy. It is designed to treat a specific surgically remediable epilepsy syndrome: unilateral medial temporal lobe epilepsy. The specific characteristics of medial temporal lobe epilepsy were outlined in two papers from Yale University [1,2]. They include antecedent febrile convulsions in childhood, auras (abdominal/visceral, autonomic, emotional, and olfactory sensations are most common), partial complex seizures, characteristic memory deficits, and seizure onsets in the anterior temporal region. Hippocampal sclerosis is the pathological substrate of medial temporal lobe epilepsy and is present in about 80% of surgical specimens from ATL if foreign tissue lesions are excluded. It consists of a characteristic pattern of neuronal loss that is most severe in area CA1 with relative sparing of the dentate granule cells and area CA2. Axonal sprouting of the mossy fibers of the dentate granule cells into the dentate inner molecular layer is also seen. The etiology of hippocampal sclerosis and the
exact relationship between the structural changes and seizure initiation remain to be completely understood. Other surgical resections for epilepsy may take place in the temporal lobe, such as foreign tissue lesionectomy or neocortical resections of the temporal cortex, but this chapter will describe the standard ATL for medial temporal lobectomy as modified by Spencer [3].
