From lateral to mesial: The quest for a surgical cure for temporal lobe epilepsy

Abstract

SUMMARYPurpose: A gap of more than a hundred years occurred between the first accounts of mesial temporal sclerosis and recognition of its role in the pathogenesis of psychomotor seizures. This paper reviews how the understanding and surgical treatment of temporal lobe epilepsy developed, particularly from the work of Penfield, Jasper, and their associates at the Montreal Neurological Institute (MNI). Methods: Publications on EEG and surgery for temporal lobe seizures from 1935 to 1953 were reviewed and charts of selected patients operated on at the MNI in the same period were examined. Attention was focused on the evolution of surgical techniques for temporal lobe epilepsy. Results: In the late 1930s, some EEG findings suggested deep-lying disturbances originating in the temporal lobe. However, it took another two decades before the correlation of clinical, neurophysiological, and anatomical findings provided evidence for the involvement of the mesial structures in psychomotor or temporal lobe seizures. From 1949 and onward, Penfield and his associates applied this evidence to extend the surgical resections to include the uncus and the hippocampus. Conclusion: The collaborative work of a team led by Penfield and Jasper at the MNI helped to define the role of neurophysiological studies in epilepsy surgery. As a result, the importance of removing the mesial structures in order to obtain better seizure control in patients with temporal lobe epilepsy became firmly established.

The neurobiology of cognitive disorders in temporal lobe epilepsy

“…Understanding of the neurobiology of disordered cognition and memory in epilepsy was accelerated by the development of organized epilepsy surgery programs. Collaboration with neuropsychology was key from the inception of these programs which involved Donald Hebb and Brenda Milner at the Montreal Neurological Institute, Ward Halstead at the University of Illinois in Chicago, and Victor Meyer at the Guy’s-Maudsley Hospital in London 4–8 .…”

“…As resection of the mesial temporal structures became a standard practice, the principal function of the hippocampus was elucidated 8, 12, 13 due to two factors.…”

Introduction

“…The surgical treatment of temporal lobe epilepsy initially was confined to resection to the temporal neocortex, but within a few years, it was fully recognized that the mesial structures needed to be resected to effect a cure (see de Almeida et al 2008;Moran and Shorvon 2009) and the work of Penfield and Murray Falconer reported at the 1953 congress showed how far knowledge had advanced. By 1953, Jasper could write that, from the physiological point of view, "the periamygdaloid and rhinencephalic portions of the temporal lobe, including the extent of the hippocampal gyri and often the pes hippocampi, are nearly always severely affected in patients with temporal lobe seizures."…”

A more balanced and inclusive view of the history of temporal lobectomy

“…I wish to make some observations on the paper “From lateral to mesial: The quest for a surgical cure for temporal lobe epilepsy” (Almeida et al, 2007). The paper arguably overemphasized the place of the work of Penfield and Jaspers at the MNI at the expense of under‐recognition of other workers.…”