Surgical Approach to MRI-Negative Extratemporal Epilepsy, Guided by Multimodal Image Fusion Techniques and Invasive Recordings.
Abstract number :
3.189
Submission category :
Year :
2001
Submission ID :
1181
Source :
www.aesnet.org
Presentation date :
12/1/2001 12:00:00 AM
Published date :
Dec 1, 2001, 06:00 AM
Authors :
B. Rydenhag, MD, PhD, Neurosurgery, Institute of Clinical Neuroscience, Göteborg, Sweden; M. Runnerstam, MD, PhD, Neurosurgery, Institute of Clinical Neuroscience, Göteborg, Sweden; A. Hedström, MD, Clinical Neurophysiology, Institute of Clinical Neurosci
RATIONALE: To use invasive EEG recordings, multimodal image fusion and neuronavigation techniques in extratemporal MRI negative cases to enable epilepsy surgery within or close to primary motor cortex.
METHODS: Two patients with medically therapy resistant epilepsy (female, 10 and 16 years old) with a normal MRI of the brain underwent interictal and ictal CBF image studies and invasive electrode recordings. The younger patient had a 5 year history of secondary generalised seizures, language and cognitive deterioration and progressive spastic diplegia. The older patient had motor seizures in the right leg in the form of epilepsia partialis continua since 10 years. Structural and functional images were fused together with the invasive electrode locations generated from CT examinations. The younger patient had a regional seizure onset region located immediately posterior to the primary leg motor area and was operated by an endopial intervascular resective technique. Neuronavigation was used. The older patient had a continuous epileptic activity in the leg motor area. A resection was judged not feasible, instead multiple subpial transections (MST) were performed within the primary leg motor area at the medial aspect of the hemisphere.
RESULTS: The pathological examination revealed unexpectedly focal cortical dysplasia in the younger patient. She is not seizure free, but has at least 75 % seizure reduction (only 6 weeks follow up). The patient also improved almost immediately in motor and language functions. At surgery of the older patient no pathological examination was possible. She has been followed for 2 years and has a more than 50 % reduction of seizures. She has taken up studies, and has a good psychosocial outcome.
CONCLUSIONS: In the absence of MRI findings the use of multimodal image techniques and invasive recordings increases the possibility to treat patients with severe epilepsy generated within or close to eloquent cortex. Peroperative neuronavigation can further increase the precision at surgery.
MST may be utilized at the medial aspect of the hemisphere.
Patients with a severe seizure situation can benefit considerably from epilepsy surgery, both neurologically and psychosocially although seizure freedom is not achieved.