Neuropathology of Patients with Multiple Surgeries for Medically Intractable Epilepsy
Vincent B Cruz, Richard A Prayson. Cleveland Clinic Lerner College of Medicine of Case Western Reserve University, Cleveland, OH; Cleveland Clinic Foundation, Cleveland, OH
Background: Surgery is a well-established treatment for patients (pts) who fail medical management of epilepsy. The success rate following surgery is generally good; however, seizures persist/recur following the initial surgery in a subset of pts. We hypothesize that in pts who require multiple surgeries for intractable epilepsy, an identifiable pathologic substrate can be found in the subsequent surgical specimen which accounts for the recurrent seizures.
Design: A retrospective study of 102 pts (56 females) with medically intractable epilepsy who have had at least 2 surgeries more than 60 days apart from 1990-2010 out of 3,157 pts who had surgery during this time interval; 15 pts had 3 or more surgeries. Pt age at time of 1st surgery ranged from 3 mos-60 yrs (mean 18.1 yrs). Duration of seizures prior to 1st surgery ranged from < 2 wks-60 yrs (mean 9.7 yrs). Time between the 1st and 2nd surgeries ranged from 0.28-15.3 yrs (mean 4.3 yrs).
Results: Pathologies at initial resection included focal cortical dysplasia (45%), tumor (19%), hippocampal sclerosis (16%), non-specific changes (13%), Rasmussen's encephalitis (6%), infarct (10%), Sturge Weber (2%), and granulomatous mengingoencephalitis (1%); 10% of pts had multiple significant pathologies. Significant pathologies were identified in 84% of cases in the 2nd surgery. Of the 89 pts that had a significant initial surgical finding, 74/89 had a significant pathology at 2nd surgery; the same pathology was identified in 49/74 of these cases. The most commonly identified pathologies at 2nd surgery included remote infarcts (likely postoperative) (N=51) and focal cortical dysplasia (N=29). Three out of the 13 pts with initially non-specific findings had a significant finding at 2nd surgery, excluding post-operative infarct. Of the 15 pts who underwent a 3rd surgery, 8 had remote infarcts and 6 had recurrent/residual tumors at 3rd surgery. Follow-up after last surgery ranged from 0.5-190 mos (mean 48 mos); 83% of pts were on anti-convulsive medication and 57% were seizure-free at last known follow-up.
Conclusions: In the majority of cases of recurrent epilepsy with at least 2 surgeries (84%), specific pathological findings accounting for seizures was found at the 2nd surgery. In most cases with significant initial pathology, a similar pathology was present at the 2nd surgery (49/89, 55%). Post-operative contusional damage may account for persistent seizures following initial surgery in a subset of pts.
Tuesday, March 20, 2012 1:00 PM
Poster Session IV # 274, Tuesday Afternoon