Abstracts

Rationale: Surgical treatment is considered for intractable temporal lobe epilepsy (TLE) which failed in multiple drug regimens. Surgical success rate of TLE is up to 90% in uncomplicated cases. However, surgical options may not be immediately available in any hospital. In these cases, the newer generation Anti-Epileptic Drugs (nAEDs) are more likely attempted while waiting for decision of surgery. The outcome of using newer generation AEDs when surgery referral is not chosen option is not known. Methods: Ninety nine patients were admitted to the epilepsy monitoring unit (EMU) of Bronson Methodist Hospital, Kalamazoo, MI from 2008 to 2010. Sixteen patients were diagnosed with intractable TLE that had failed multiple AEDs. These intractable TLE cases include bilateral temporal onset, multi-drug failures, non-lesional, and hippocampal atrophy. Cases involving the frontal lobe were excluded. Among the 16 patients, untried nAEDs were added or the current AEDs that were not working well to control seizures were replaced. These untried AEDs included felbamate, gabapentin, zonisamide and lacosamide. Seizure frequency was assessed at each clinical visit following the medication adjustments. Treatment outcome was classified by subjective scales. Results: Outpatient follow up occured no less than 3 months and up to one year. In follow up, 3 (Class 1: 19%)out of 16 became near seizure free or no more than one seizure per six month, 8 (Class 2: 50%) had worthwhile reduction of seizure frequency greater than 50%, and 5 (Class 3: 31%) had no improvement despite of AED changes. Among the 5 cases of no improvement, 2 then went on to be eligible for surgical treatment and experienced immediate seizure reduction. Felbamate was the most frequently selected agent to be tried (56%) and demonstrated moderate seizure reduction without adverse side effect. Gabapentin contributed to a seizure free state in 2 cases.Conclusions: Aggressive use of nAEDs may still have a role for those patients with intractable TLE. A randomized rigorous outcome study of surgery and AED treatment reported 58% seizure free after surgery group v.s. 8% seizure free in earlier generation AED treatment group (Wiebe, et.al.). Our retrospective data base review study, while it is not randomized, demonstrated comparable 19% near seizure free rate. These 19% patients did not proceed to surgical treatment. However, only 69% of patients experienced more than 50% seizure reduction by application of untried newer generation AEDs, while 90% patients could be seizure free after the tempral lobectomy. The limitation of the study is the shorter follow up duration, usage of subjective outcome scale, and small number of cases.