A conservative estimate is that more than 100,000 people with epilepsy in the United States alone have uncontrolled seizures and could benefit from surgery. Most of them have seizures that arise from a problem in a temporal lobe of the brain, and the most common operation to treat refractory epilepsy is anterior temporal lobectomy. This is a procedure with a proven record of efficacy, eliminating or greatly reducing the prevalence of seizures in trial after trial. A group of researchers at the University of Pennsylvania and Dartmouth University decided to delve deeper into the impact of this procedure on the lives of patients in the first five years after lobectomy.
The test subjects were 89 volunteers, ranging from 10 years old to 60, all suffering persistent seizures at least once a month for at least one straight year. All had elected to have surgery after at least three different antiepileptic drugs (AEDs) and one attempt at combination therapy failed to improve their condition. Neurologists had confirmed in each case that their seizures probably arose from a single temporal lobe and could therefore be addressed by its excision; all those patients whose seizures originated in more than one site, or in a site other than the temporal lobe, were excluded from surgery because of the obvious undesirability of removing large or valuable pieces of brain tissue. Surgery does not immediately cancel the need for medication; patients were initially advised to continue taking their AEDs at moderate doses for two years after study, and this was later extended to five years.
The results of surgery
The most basic yardstick for measuring the value of any surgery aimed at reducing seizures is obviously the impact on seizure frequency. This was documented at two weeks, two months, six months, and again at one year after surgery. Follow-up continued every year in those patients who were seizure-free to see how long they stayed that way. Patients were grouped into four categories according to the degree of improvement. Class One patients were seizure-free after surgery, or currently seizure-free for at least one year (exceptions were made for isolated seizures associated with withdrawal of medication). Class Two patients were those who still had occasional seizures, but no more than three in a year – a significant improvement in a group that had previously averaged at least eight seizures per month. Class Three patients had more than three seizures in a year, but still registered a post-surgery reduction of over 80% in seizure frequency. Finally, Class Four patients included all patients whose seizures had become less frequent, but by less than 80%, and those who had registered very little improvement or none at all.
By any standards, the surgery was very effective. After five years, 62 patients (70%) were in Class One, a further eight (9%) were in Class Two, and 10 more (11%) were in Class Three. Thus, 90% of patients had achieved significant relief from their seizures, and most of them were effectively cured. Only five patients (6%) had fallen into Class Four, while four (4%) had died of various causes, none of them related to surgery. More than half of all patients never had another seizure following surgery. (This does not include those seizures that sometimes follow immediately after the operation, which are caused by the trauma to the brain inherent in surgery, and do not reflect any permanent epileptic condition.)
Lobectomy does not impair intelligence
One common misconception about lobectomies (arising, no doubt, from the connotations of the similar word lobotomy) is that it can reduce intelligence. IQ tests administered to patients before and one year after surgery showed no change in verbal scores and a noticeable improvement in the performance score, especially among those who had left (as opposed to right) temporal lobectomies. Both left and right-side patients (especially left) raised their average overall IQs. Thirty-minute visual memory and facial memory were also improved. Most importantly, the patients showed greatly reduced scores on standard tests of depression and anxiety; they were happier and more relaxed.
These changes could not be expressed more clearly than in the improvements that those patients who became seizure-free achieved in their own lives over the five years following surgery. Before the operation, only 34% of all patients were working full-time and 24% were unemployed. Five years later, 63% were working full-time and only 11% were unemployed. Full-time employment rose even higher in the majority who became seizure-free, and unemployment in Class One patients dropped to 3% – below the national average. The psychological, social and material benefits of having a paying job, which can hardly be overestimated, are among the biggest dividends of successful treatment of seizures.
Rarely does a medical procedure offer such a clear and long-term improvement to the well-being of patients as temporal lobectomy. In the face of such encouraging findings, the researchers recommend that patients with epilepsy focused in the temporal lobe be encouraged to consider surgery as soon as the failure of drug treatment becomes apparent. Much unnecessary suffering and marginalization could be avoided and thousands of people rescued from the trap of epilepsy if this procedure were applied in more cases.