INVITED COMMENTARY

Epilepsy Surgery: Still Underutilized After All These Years

Carl W. Bazil

Published online: 24 May 2012# Springer Science+Business Media, LLC 2012

Since the creation of comprehensive epilepsy centers in the1980s, it has been widely known that epilepsy surgery, incarefully selected individuals, carries by far the best chanceof seizure freedom (and restoration of a normal quality oflife) for patients with refractory epilepsy. But although thenumber of patients potentially appropriate for epilepsy sur-gery number in the hundreds of thousands, the number ofactual surgeries in the United States has remained in thethousands. Even when surgery is performed, the averagetime from determination of medical failure to epilepsy sur-gery is measured not in years but in decades—decades thatusually encompass the years of highest potential productivityin patients’ lives. When surgery is finally performed andseizures stopped, few patients were then able to overcome alifetime of disability to obtain full-time employment.

What is the evidence in favor of epilepsy surgery? Is lackof study responsible for the small number of epilepsysurgeries? Sadly, the answer is no. The first randomizedstudy of epilepsy surgery was published in 2001, over20 years ago [1]. For the first time, the utility of thisprocedure was proven by the gold standard of scientificresearch. Patients who received surgery in this study had anearly 60 % chance of seizure freedom, compared with lessthan 10 % in those who continued medical therapy.

This randomized study followed patients for only 1 year—is the benefit of epilepsy surgery sustained? In another study,long-term outcome (up to 19 years) was determined in patientsundergoing epilepsy surgery at a single surgical center [2]. Atotal of 615 adults were evaluated, most of which had anterior

temporal lobectomies. The results show over 50 % free ofdebilitating seizures after 5 years, and nearly as many at10 years, following epilepsy surgery. Although not ashigh as the 80 % seizure freedom sometimes seen in thefirst year, these outcomes remain much more favorablethan medical therapy, where a maximum of 10 % seizure freeis usually seen.

Perhaps a more telling, though limited study, looked atearly epilepsy surgery in patients with temporal lobe epilepsyand mesial temporal sclerosis (ERSET [Early SurgicalTherapy for Drug-Resistant Temporal Lobe Epilepsy]) [3].This study was meant to answer whether very early treatmentwith epilepsy surgery was effective at controlling seizures andimproving quality of life, addressing the concern that delayin surgery was also a significant problem. In most centersthe time between becoming “refractory” (failing at leasttwo trials of appropriate anticonvulsant drugs at therapeu-tic doses) and referral for epilepsy surgery is up to 20 years;in this study patients could be refractory for no more than2 years. The reasons for this long delay are not known;however, epilepsy specialists believe this long delay resultsin permanent deficits even with successful surgery, aspatients have already been impaired with regard to workand personal opportunities for many years. Subjects in theERSET study were randomized to early surgical interven-tion or best medical management. There were no patientsin the medical management group that were free of seiz-ures in a 2-year follow-up, while the majority (11/15) in thesurgical group were seizure free. This result is comparableto previous trials. Quality of life improved significantly inthe surgery group. Although this study was limited by lowenrollment, leading to early termination of the study, thefindings clearly show that quality of life improves in thesepatients as well as in those with much longer periods ofintractability.

C. W. Bazil (*)Columbia University College of Physicians and Surgeons,710 West 168th Street, 7th Floor,New York, NY 10032, USAe-mail: cwb11@columbia.edu

Curr Neurol Neurosci Rep (2012) 12:348–349DOI 10.1007/s11910-012-0287-2

With all of this information that epilepsy surgery is by farthe best treatment for appropriate patients with intractableepilepsy, and with a practice parameter from the AmericanAcademy of Neurology favoring surgical evaluation forpatients with intractable epilepsy [4], is there evidence thatthe number of procedures is increasing? Unfortunately, theevidence suggests the reverse. A recent cohort-based studyshowed that although hospital admissions for refractoryepilepsy are actually increased overall, the number ofepilepsy surgeries has decreased [5]. The results suggestthat this trend is associated with more treatment at hospitalsthat do not have epilepsy surgery available. This implies thatappropriate patients (those with intractable epilepsy), whentreated at hospitals that are not comprehensive epilepsycenters, do not receive appropriate referral for epilepsysurgery. If true, this is a failure of the system and anargument for more formal pathways for evaluation andtreatment of patients with intractable epilepsy.

The possible reasons for lack of referral for epilepsysurgery are many. It may be that few practitioners knowthe high chance of cure with epilepsy surgery, although witha practice parameter in place by the American Academy ofNeurology this seems unlikely. It may be that patients arewary of any sort of brain surgery, and therefore are notresponsive when the idea is presented. However, whenpresented confidently by an experienced epilepsy specialist,most patients would be convinced.

The two studies cited above further prove that intractableepilepsy needs aggressive evaluation and possibly surgicaltreatment. Standard of care must be that as soon as a patientis defined as intractable—once two appropriate anticonvul-sants fail to completely control seizures—video-EEG

monitoring is warranted, ideally at a comprehensive epilepsycenter where all of the options, including epilepsy surgery, canbe discussed with the patient once evaluation is complete. Ifthe diagnosis is intractable epilepsy, the patient should imme-diately be considered for possible epilepsy surgery. In cases ofnonepileptic seizures, who will commonly also be identifiedin this way, these centers are also more experienced inredirecting care.

Disclosure No potential conflicts of interest relevant to this articlewere reported.

References

1. Wiebe S, Blume WT, Girvin JP, Eliasziw M. A randomized, con-trolled trial of surgery for temporal-lobe epilepsy. N Engl J Med.2001;345(5):311–8.

2. de Tisi J, Bell GS, Peacock JL, et al. The long-term outcome of adultepilepsy surgery, patterns of seizure remission, and relapse: a cohortstudy. Lancet. Oct 15;378(9800):1388–95.

3. Engel Jr J, McDermott MP, Wiebe S, et al. Early surgical therapy fordrug-resistant temporal lobe epilepsy: a randomized trial. JAMA.2012;307(9):922–30.

4. Engel Jr J, Wiebe S, French J, et al. Practice parameter: temporallobe and localized neocortical resections for epilepsy: report of theQuality Standards Subcommittee of the American Academy ofNeurology, in association with the American Epilepsy Society andthe American Association of Neurological Surgeons. Neurology.2003;60(4):538–47.

5. Englot DJ, Ouyang D, Garcia PA, Barbaro NM, Chang EF. Epilepsysurgery trends in the United States, 1990–2008. Neurology. Apr17;78(16):1200–6.

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