Objective: Patients with intractable focal epilepsy due to intracranial tumors are excellent
candidates for epilepsy surgery. According to the literature the percentage of seizure-free
patients post surgery varies between 65–90%. Incomplete tumor resection and/or insufficient
removal of tumor-associated focal cortical dysplasia are risk factors for good seizure
outcome. Role of invasive diagnostic is not fully established yet.
Methods: Retrospective evaluation of data of 43 patients with intracranial tumors (out of
308 patients, who received epilepsy surgery between September 1998 and October 2010at
the Epilepsy Center for Children and Adolescents, Schoen Klinik Vogtareuth)
Results: Age of onset of epilepsy: 5.1yrs (1m.-11), age at surgery: 10.8yrs (2–28), post-surgical
follow-up: 68 mths (5.3–147). localisation of epilepsy: temporal 19/43, temporal plus
15/43, extratemporal 9/43. Invasive recordings: 3/43. histology: ganglioglioma 27/43,
DNET 7/43, astrocytoma 2/43, misc. 3/43, pending 4/43. post-surgical seizure outcome:
seizure-free 26/43, only aura 8/43, >90% seizure reduction 4/43, >50% seizure reduction
1/43, unchanged 1/43, pending 1/43. Reasons for surgical failure: incomplete resection
of tumor (planned to avoid functional deficit/unplanned) 3/6, incomplete resection
of tumor-associated focal cortical dysplasia 2/6, unknown 1/6.
Conclusion: Success of epilepsy surgery in our series is comparable to those in other publications.
Reasons for surgical failure were incomplete resection of tumor or tumor-associated
focal cortical dysplasia. Existence of tumor-associated focal cortical dysplasia,
which might be undetected by standard resolution MRI should be considered in presurgical
evaluation and resection planning in patients with drug resistant focal epilepsy to
increase the chances for complete seizure relief.
