INTERICTAL HIGH-FREQUENCY OSCILLATIONS INDICATE SEIZURE ONSET ZONE IN PATIENTS WITH FOCAL CORTICAL DYSPLASIA
Abstract number :
1.060
Submission category :
3. Clinical Neurophysiology
Year :
2009
Submission ID :
9406
Source :
www.aesnet.org
Presentation date :
12/4/2009 12:00:00 AM
Published date :
Aug 26, 2009, 08:12 AM
Authors :
Milan Brazdil, J. Halamek, P. Jurak, P. Daniel, R. Kuba, J. Chrastina, Z. Novak and I. Rektor
Rationale: Interictal high-frequency oscillations (HFO) were recently identified in recordings from depth macroelectrodes in epileptic patients. They seem to be a reliable indicator of the seizure onset zone (SOZ). Conflicting HFO characteristics were reported in patients with cortical dysplasia. Methods: Ten-minute SEEG recordings were analyzed in four patients with medically intractable partial seizures due to focal cortical dysplasia type IIA. The characteristics of HFO within the SOZ, irritative zone, and remote brain areas were investigated. Results: Whilst the rate of occurrence for ripples (80-200 Hz) was significantly higher in recordings from within than outside the SOZ, the rate of fast ripples (200-450 Hz) was a less reliable index of SOZ. Interestingly, the mean powers across subjects were significantly higher within than outside the SOZ in both ripple and fast ripple frequency ranges. Conclusions: Our study demonstrates a capacity of interictal HFO to detect the SOZ in focal cortical dysplasia.
Neurophysiology