gms | German Medical Science

57th Annual Meeting of the German Society of Neurosurgery
Joint Meeting with the Japanese Neurosurgical Society

German Society of Neurosurgery (DGNC)

11 - 14 May, Essen

Local anticonvulsant therapy in rats with focal cortical epilepsy by gabapentin-containing biodegradable polymers matrices

Lokale Antikonvulsiva-Therapie in der Behandlung von Ratten mit fokaler kortikaler Epilepsie durch Gabapentin-haltige bioabbaubare Polymermatrizen

Meeting Abstract

  • corresponding author T.M. Freiman - Neurochirurgische Klinik, Universitätsklinikum, Albert-Ludwigs-Universität, Freiburg
  • M.C. Müller - Neurochirurgische Klinik, Universitätsklinikum, Albert-Ludwigs-Universität, Freiburg
  • T.J. Feuerstein - Klinische Neuropharmakologie, Universitätsklinikum, Albert-Ludwigs-Universität, Freiburg
  • J. Zentner - Neurochirurgische Klinik, Universitätsklinikum, Albert-Ludwigs-Universität, Freiburg

Deutsche Gesellschaft für Neurochirurgie. Japanische Gesellschaft für Neurochirurgie. 57. Jahrestagung der Deutschen Gesellschaft für Neurochirurgie e.V. (DGNC), Joint Meeting mit der Japanischen Gesellschaft für Neurochirurgie. Essen, 11.-14.05.2006. Düsseldorf, Köln: German Medical Science; 2006. DocP 02.11

The electronic version of this article is the complete one and can be found online at:

Published: May 8, 2006

© 2006 Freiman et al.
This is an Open Access article distributed under the terms of the Creative Commons Attribution License ( You are free: to Share – to copy, distribute and transmit the work, provided the original author and source are credited.



Objective: Patients with pharmacoresistant epilepsy caused by an epileptogenic focus in an eloquent brain area are difficult to treat. An operative resection or multiple subpial transsection may result in severe neurological deficits (hemiparesis, motoric- or sensomotoric aphasia). Therefore we have developed a novel experimental technique by implanting biodegradable gabapentin (GBP)-continaing polymer matrices onto the cortex of rats with tetanus toxin induced focal cortical epilepsy.

Methods: Tetanus toxin (50 µg) was injected stereotactically into the motor area 4 of Wistar rats. Epileptic activity was measured by video-electro-encephalography (video-EEG). In a second operation the scull was reopened and a biodegradable GBP-polymer matrix was implanted onto the cortex where the epilepsy was induced. In a second video-EEG monitoring the seizure time was compared with the pre-implantation video-EEG. As controls against tetanus toxin served injections with normal saline (0.9% NaCl). GBP-polymer matrices were controlled with saline containing polymer matrices.

Results: Ten rats were injected with tetanus toxin into the cortical motor area 4. As control 10 rats were injected with normal saline. In video-EEG-monitoring 8 of 10 animals with tetanus toxin injections developed epilepsy. None of the saline injected animals developed epilepsy. In a second operation 4 rats were reopened and 2 were implanted with GBP-polymer matrices cortically. One sham-animal received a GBP-polymer matrix subgaleal without opening the scull and one sham-animal received a saline polymer matrix which was implanted on the cortex surface. Effects of GBP-polymer implants on frequency and duration of epileptic discharges will be presented.

Conclusions: Application of local anticonvulsant therapy by polymer matrices in vivo is a new therapeutic concept which may offer an option for patients with pharmacoresistant epilepsy in eloquent brain areas.