gms | German Medical Science

Objective: Pharmacoresistant epilepsy is a devastating disease, severely influencing patients’ quality of life. In approximately one third of the adult patients, the epileptogenic focus is localized outside the temporal lobe. Surgical resection of extratemporal focal epilepsy is a widely accepted treatment option. However, seizure control is only achieved in about 50% of the cases and a considerable number of patients continue to suffer from seizures. In these cases, reoperation may be a useful option. It was the aim of this study to analyze clinical and epileptological results in patients, who underwent reoperation due to failed surgical treatment of extratemporal epilepsy.

Methods: This single-center study comprises a consecutive series of 49 patients with extratemporal epilepsy who underwent reoperation after failed first surgery. Comprehensive data including preoperative diagnostic modalities, surgical treatment, histopathological findings, and clinical as well as epileptological outcome were analyzed.

Results: Reoperations were performed for residual lesions (n=26), recurrence of the resected pathology (n=5), and new hypothesis regarding the epileptogenic focus (n=18). Surgeries were located as follows: frontal (n=19), parietal (n=5), occipital (n=7) and insular (n=1). In 17 cases resection included more than one lobe. In 37 cases an extended lesionectomy and in 9 patients a lobectomy was performed, while 3 patients had a hemispherectomy. Histopathological evaluation of the resective specimen revealed focal cortical dysplasia (n=22), tumors (n=13), and gliosis (n=14). After a mean follow-up of 51 months, 18 patients (37%) remained seizure free (Engel I), and 23 (48%) had favorable outcome (Engel I-II). Temporary morbidity was encountered in 13 cases (26%), while permanent morbidity occurred in 9 cases (18%). There was no perioperative death. Resections including more than one lobe had higher complication rates as compared to circumscribed resections within one lobe (p=0.02). Complete resection of the epileptogenic focus (p=0.04) and lack of epilepsy typical potentials after operation (p=0.02) were associated with favorable seizure outcome (Engel I), while gliosis was a negative prognostic factor with respect to postoperative seizure control (p=0.01).

Conclusion: Second resective procedure can be taken into consideration in patients with failed surgical treatment for extratemporal epilepsy and may provide satisfying epileptological results with an acceptable morbidity. Patients, in whom complete resection of the epileptogenic focus is possible, seem to be suitable candidates for reoperation, while patients with gliosis are less likely to benefit from second operation.