Temporal Lobectomy for Refractory Epilepsy in the U.S. Military

Military Medicine, Mar 2005 by Erickson, Jay C, Ellenbogen, Richard G, Khajevi, Kaveh, Mulligan, Lisa, Et al

Neuropathological findings of resected tissue were available for 80 (95%) of 84 patients. The most common pathological diagnosis was mesial temporal sclerosis-gliosis (38 of 80 patients, 47.5%), followed by neoplasm (18 of 80 patients, 22.5%; 9 astrocytomas, 4 gangliogliomas, 3 dysembryonic neuroepithelial tumors, 1 oligodendroglioma, and 1 hamartoma), vascular malformation (9 of 80 patients, 11.3%; 5 cavernous angiomas, 3 arteriovenous malformations, and 1 unspecified venous anomaly), dysplasia (5 of 80 patients, 6.3%), and ischemia (2 of 80 patients, 2.5%). No pathology was identified in 8 (10%) of 80 cases. Seizure outcomes according to pathology are summarized in Table III. Mesial temporal sclerosis correlated with postoperative seizure remission (p

Quality-of-life indicators are summarized in Table IV. Driving and employment rates significantly increased after surgery, whereas anticonvulsant use significantly decreased. Postoperative driving status was strongly associated with seizure outcomes, with 23 (96%) of 24 driving having favorable seizure outcomes compared with only 5 (31%) of 16 not driving (p

No deaths occurred in the perioperative period or during the follow-up period. Significant long-term adverse effects occurred for 4 (5%) of 84 patients, including hemiparesis for 2 patients, disabling memory impairment for 1 patient, and dysphasia for 1 patient. Both cases of postoperative hemiparesis occurred with en bloc resections.

As summarized in Table V, there were several differences between active duty patients and non-active duty patients. Active duty patients had a later onset of epilepsy and a shorter latency to surgery. No active duty patients had seizure onset in infancy or childhood. The proportion of patients with lesional epilepsy (i.e., epilepsy attributable to a tumor or vascular anomaly) was greater in the active duty group (6 of 10 patients, 3 with low-grade neoplasms and 3 with vascular malformations). No active duty members had mesial temporal sclerosis.

All 10 of the active duty patients were in the process of being medically discharged from the military at the time of surgery, in accordance with military retention standards pertaining to epilepsy. However, 5 (50%) of 10 military members achieved complete postoperative seizure remission without adverse effects and were therefore retained on active duty. Their duty restrictions were gradually reduced over a 2-year period. We are not aware of any adverse effects of epilepsy surgery on their military duty performance. In contrast, the 5 (50%) of 10 active duty patients who had incomplete seizure remission, and were therefore incapable of full military duty, were discharged from the military for failure to meet medical retention standards.

Discussion

This is the first report of epilepsy surgery outcomes in a military population. We found that 2 years after partial temporal resection, 66% of patients experienced seizure remission and an additional 26% experienced seizure improvement. Surgery also improved several quality-of-life indicators. The seizure outcomes, complication rates, and quality-of-life outcomes were similar to those reported in contemporary studies from nonmilitary centers.1-7