Second Operation after the Failure of Previous Resection for Epilepsy

Abstract

We present our surgical experience with second operations in 15 patients with recurrent intractable partial seizures after resection for epilepsy. The interval from the first operation until the first recurrence of seizures ranged from 1 day to 7 months (mean, 62 days);. The interval between the first and second operations ranged from 3 months to 12 years (mean, 38 months);. Detailed video-electroencephalographic interictal and ictal recording was performed in all patients (invasive electrodes were used in 11 patients);. Ictal onset was shown to be remote from the zone of previous resection in 3 of 15 cases (all 3 extratemporal and in the ipsilateral hemisphere);. Recurrent seizures arose from the area of previous extratemporal resection in 2 of 15 patients, and from the area of previous temporal resection in 10 of 15 patients. Both cases of extratemporal recurrences and 3 of the 10 cases of temporal lobe recurrences in the area of previous resection were associated with residual unresected structural lesion. Of the 10 patients with local temporal recurrence, 6 had proven epileptogenicity in the residual mesial structures, and 4 had residual epileptogenicity in the unresected lateral temporal lobe. The patients have been monitored for 8 to 82 months (mean, 18 months); after the second operation: 7 patients (47%); have remained seizure-free and another 5 (33%); have achieved a reduction in seizure frequency of more than 90%. There was no mortality or significant morbidity in this series. We conclude that the extent and distribution of residual epileptogenicity after failed epilepsy surgery are highly variable. Recurrent intractable seizures usually (but not always); arise from the area of previous resection, and reflect residual structural lesions or epileptogenic foci. Individualized second operations can be safe and effective, and may provide selected patients with “failed cases” another chance at seizure control. Patient selection and the technical aspects of remapping and second operations are discussed.

Natural History of Recurrent Seizures After Resective Surgery for Epilepsy

“…We believe that this information allows rational prognostication and counseling of patients with recurrent postoperative seizures. It will assist in decision making regarding possible reoperation (Awad et al, 1991).…”

Placement of subdural grids in pediatric patients: technique and results

“…Sometimes, an invasive evaluation fails to localize seizure origin. In selected patients where invasive monitoring fails to identify the site of seizure origin, reinvestigation can achieve localization of the seizure onset and allow a successful surgical treatment [44][45][46]. Due to the relatively prolonged period of reduced activity in these patients, other serious complications such as deep venous thrombosis, pulmonary embolism, pneumonia, and other sequelae of immobility can develop.…”

Magnetoencephalography in presurgical epilepsy evaluation

“…Shifting of normal brain into resection cavities may cause gross distortions of topographic anatomy in these patients [108]. MEG should be superior to scalp EEG in this specific situation, because magnetic fields are not distorted by skull and dura defects, which may cause false localization on scalp EEG.…”