Lesional Occipital Lobe Epilepsy of Childhood Onset: Clincal Features, Etiology and Outcome.
Abstract number :
2.223
Submission category :
Year :
2001
Submission ID :
1692
Source :
www.aesnet.org
Presentation date :
12/1/2001 12:00:00 AM
Published date :
Dec 1, 2001, 06:00 AM
Authors :
R.K. Maganti, MD, Neurology, University of Wisconsin, Madison, WI; R.D. Sheth, MD, Neurology, University of Wisconsin, Madison, WI; P.A. Rutecki, MD, Neurology, University of Wisconsin, Madison, WI; B.E. Gidal, PharmD, Pharmacy, University of Wisconsin, M
RATIONALE: Lesional occipital lobe epilepsy accounts for 10% patients undergoing epilepsy surgery. Cortical dysplasias and developmental tumors are common etiologies for childhood onset occipital lobe epilepsy. Some have suggested less favorable surgical outcome in patients with cortical dysplasia. Outcomes of medically and surgically treated patients with lesional occipital lobe epilepsy of childhood onset were examined.
METHODS: A search of our epilepsy data base queried to identify patients with symptomatic occipital lobe epilepsy yielded 11 pts with lesional occipital epilepsy. Clinical characteristics, interictal and ictal EEG characteristics, MRI, fMRI and PET were studied. Outcome in those who had surgery was compared to those who were managed medically.
RESULTS: Mean age of seizure onset was 12 years. Duration of epilepsy prior to surgery ranged from 3 to 40 years. Visual auras occured in 9 of 11 patients. Only 2 had visual field defects despite lesions in the striate cortex. Ictal onset was in the occipito-temporal regions in 8 patients and occipito-parietal region in 3. Imaging showed focal cortical dysplasia in 5, tumours in 3 and perinatal ischemic lesions in 3 patients. fMRI (6/11) showed normal or mildly reduced activation of involved visual cortex with dysplasia (3/6) and severely reduced activation with tumors or infarcts (3/6). 6 patients were surgically treated following intracranial monitoring and electrocorticography. Following surgery 4 pts (66%) had occasional auras or were seizure-free (Engle[ssquote]s class 1A or 1B) and the remaining 2 had rare disabling seizures (Class 2B). Post-op pathology showed that 2 pts had cortical dysplasia, 2 had tumors (ganglioglioma and oligodendroglioma) and 1 had an infarct. 1 pt had both cortical dysplasia and tumor(astrocytoma). All had postoperative field defect. Compared to the surgically treated group all 5 medically treated patients continue to be intractable.
CONCLUSIONS: Type of lesion did not impact ictal semiology. All surgically treated patients experienced either seizure freedom or a marked reduction of seizures compared to all 5 medically managed patients who continued to be intractable. Completeness of resection based on post-op MRI may underlie the improved results we experienced compared to earlier reports. Unlike prior reports, equally good results were obtained for both cortical dysplasias as for tumors. Surgical management of childhood onset lesional occipital epilepsy should probably be considered earlier in the course of epilepsy.