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Objective To explore decision-making from patients’ perceptions of risks and benefits of epilepsy surgery for refractory focal seizures. Methods Using constructivist grounded theory, in-person interviews were conducted with 35 adults with refractory focal epilepsy who were undergoing a pre-surgical evaluation or who had consented for surgery. Results For this sample of participants decision-making about surgery was complex, centering on the meaning of illness for the self and the impact of epilepsy and its treatment for significant others. Two interrelated categories crystalized from our data: the unique context of brain surgery and how the decisional counterweights of risks and benefits were considered. Discussion Exploring components of decision-making from the patients’ perspective afforded an opportunity to describe thought processes intrinsic to how people with drug-resistant epilepsy weighed their treatment options. Tensions were evident in how decisions were made. We use the analogy of an imaginary tightrope-walker to create a visual image of what patients face as they consider the illness experience (past and present), their hopes for the future, and the simultaneous uncertainty centered around balancing the counterweights of treatment risks and benefits.

Surgical treatment for epilepsy has made tremendous strides in the past few decades as a result of advances in neurodiagnostics—particularly structural and functional neuroimaging—and improved surgical techniques. This has not only resulted in better outcomes with respect to epileptic seizures and quality of life, and reduced surgical morbidity and mortality, but it has also increased the population of patients now considered as surgical candidates, particularly in the pediatric age range, and enhanced cost-effectiveness sufficient to make surgical treatment available to countries with limited resources. Yet surgical treatment for epilepsy remains arguably the most underutilized of all accepted medical interventions. In the United States, less than 1% of patients with pharmacoresistant epilepsy are referred to epilepsy centers. Although the number of epilepsy surgery centers has increased appreciably over the past two decades, the number of therapeutic surgical procedures performed for epilepsy has not increased at all. For patients who are referred, the average delay from onset of epilepsy to surgery is more than 20 years—too late for many to avoid a lifetime of disability or premature death. Not only has there been no consistent message to convince neurologists and primary care physicians to refer patients for surgery, but the increase in epilepsy surgery centers in the United States has appeared to result in a divergence of approaches to surgical treatment. Efforts are still needed to further improve the safety and efficacy of surgical treatment, including the identification of biomarkers that can reliably determine the extent of the epileptogenic region; however, the greatest benefits would derive from increasing access for potential surgical candidates to epilepsy surgery facilities. Information is needed to determine why appropriate surgical referrals are not being made. Consensus conferences are necessary to resolve controversies that still exist regarding presurgical evaluation and surgical approaches. Standards should be established for certifying epilepsy centers as recommended by the Institute of Medicine's report on epilepsy. Finally, the epilepsy community should not be promoting epilepsy surgery per se but instead emphasize that epilepsy centers do more than epilepsy surgery, promoting the message: All patients with disabling pharmacoresistant seizures deserve evaluation by specialists at epilepsy centers who can provide a variety of advanced diagnostic and therapeutic services.

Mesial temporal lobe epilepsy is the most common form of human epilepsy, and its pathophysiological substrate is usually hippocampal sclerosis, the most common epileptogenic lesion encountered in patients with epilepsy. The disabling seizures associated with mesial temporal lobe epilepsy are typically resistant to antiepileptic drugs but can be abolished in most patients by surgical treatment. Anteromesial temporal resection, therefore, is the most common surgical procedure performed to treat epilepsy, and stereo-tactically implanted intracerebral electrodes are required in some patients to localize the epileptogenic region. This clinical setting provides a large number of patients for invasive in vivo research with microelectrode and microdialysis techniques and in vitro research following surgical resection on a single epileptic disorder. Consequently, much has now been learned about the fundamental neuronal mechanisms underlying the epileptogenic properties of the human hippocampus in mesial temporal lobe epilepsy. Parallel reiterative studies in patients and animal models of this disorder indicate that enhanced inhibition, in addition to enhanced excitation, underlies the appearance of hypersynchronous neuronal discharges responsible for generating spontaneous seizures. Recent studies have elucidated what may be unique electrophysiological markers of epileptogenicity, which could have valuable diagnostic utility. Although basic research on mesial temporal lobe epilepsy may ultimately suggest novel approaches to treatment and prevention, attention must also be given to maximizing the application of available effective treatments. In particular, the safety and efficacy of surgical therapy has greatly improved in recent years, yet this alternative treatment remains seriously underutilized worldwide. An appropriate increase in referral of patients with this surgically remediable syndrome to epilepsy centers will not only relieve a great many patients of their disabling seizures and reduce the burden of epilepsy but will also provide increased opportunities for invasive research that could ultimately result in even more effective therapies or cures.

The majority of patients with complex partial seizures of unilateral temporal lobe origin have interictal temporal hypometabolism on [18F]fluorodeoxyglucose positron emission tomography (FDG PET) studies. Often, this hypometabolism extends to ipsilateral extratemporal sites. The use of accurately quantified metabolic data has been limited by the absence of an equally reliable method of anatomical analysis of PET images. We developed a standardized method for visual placement of anatomically configured regions of interest on FDG PET studies, which is particularly adapted to the widespread, asymmetric, and often severe interictal metabolic alterations of temporal lobe epilepsy. This method was applied by a single investigator, who was blind to the identity of subjects, to 10 normal control and 25 interictal temporal lobe epilepsy studies. All subjects had normal brain anatomical volumes on structural neuroimaging studies. The results demonstrate ipsilateral thalamic and temporal lobe involvement in the interictal hypometabolism of unilateral temporal lobe epilepsy. Ipsilateral frontal, parietal, and basal ganglial metabolism is also reduced, although not as markedly as is temporal and thalamic metabolism.