Posterior quadrant epilepsy surgery: predictors of outcome.
OBJECTIVE
To identify predictors of seizure recurrence following posterior quadrant epilepsy surgery.


METHODS
Between 1983 and 2008, 43 medically refractory epilepsy patients underwent posterior quadrant epilepsy surgery. Epilepsy surgery involved the occipital lobe in all cases; some cases also included resection of the adjacent parietal or temporal cortex. Using a logistic regression model, we evaluated the relationship between outcome (Engel class I-IV) and 5 outcome predictors: absence of a visual aura, a temporal lobe type aura, versive head movement unaccompanied by a visual aura, non-focal interictal scalp EEG, and surgical pathology other than low grade tumor or cortical dysplasia. We also determined the relative risk for significant post-operative cognitive decline of Wechsler intelligence test score among those receiving complete lobectomies compared to those receiving partial lobectomies.


RESULTS
Overall, outcome was favorable at 1 year following surgery: 22 (51.2%) patients Engel class I, 10 (24%) patients Engel class II, 5 (12%) patients Engel class III, and 6 (14%) patients Engel class IV. The 3 best univariate predictors of seizure recurrence were versive head movement unaccompanied by visual aura, non-focal interictal scalp EEG, and pathology other than low grade tumor or cortical dysplasia. A multivariate predictor combining temporal lobe type aura, versive head movement unaccompanied by visual aura, non-focal interictal scalp EEG, and pathology other than low grade tumor or cortical dysplasia was optimum. Complete lobectomy significantly increased the risk of post-operative decline of Wechsler intelligence score.


CONCLUSIONS
These findings indicate that posterior quadrant epilepsy surgery may provide sustained seizure control. A multivariate model combining temporal lobe type aura, versive head movement unaccompanied by a visual aura, non-focal interictal scalp EEG, and pathology other than low grade tumor or cortical dysplasia may contribute to predicting seizure recurrence following posterior quadrant epilepsy surgery. The extent of cortical resection may predict significant cognitive decline in post-operative Wechsler intelligence score.
Department of Neurology, Medical College of Georgia, Georgia Health Sciences University, Augusta, GA 30912, USA. kristin.davis@medicalcenterclinic.com
Kristin L
KL
Davis
Anthony M
AM
Murro
Yong D
YD
Park
Gregory P
GP
Lee
Morris J
MJ
Cohen
Joseph R
JR
Smith
D000293:Adolescent; D000328:Adult; D002648:Child; D004827:Epilepsy / Q000175:diagnosis / Q000503:physiopathology* / Q000601:surgery*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D019635:Neurosurgical Procedures / Q000379:methods*; D009778:Occipital Lobe / Q000503:physiopathology* / Q000601:surgery*; D011237:Predictive Value of Tests; D016896:Treatment Outcome; D055815:Young Adult