Trial Information

Surgery as a Treatment for Medically Intractable Epilepsy

Objective

This protocol is being performed to study the normal human biology and disease pathogenesis
(natural history) in patients with medically intractable epilepsy, 2) provide standard
surgical treatment of medically intractable epilepsy, 3) follow the course of patients after
epilepsy surgery, and 4) to investigate neurophysiological correlates of human cognitive
processes such as memory, learning, attention, language, perception, and action.
Neurophysiologic recordings will be compared with those in the resting awake state and
during sleep.. Any treatment under this protocol will be based on the current standard of
care for epilepsy surgery.

Study Population

Patients 8 years and older whose seizures are uncontrollable with medication may participate
in this study.

Study Design

Patients will be screened by study neurologists to confirm their diagnosis of medically
intractable epilepsy. Patients that do not have a confirmed diagnosis of medically
intractable epilepsy will be offered further evaluation in protocol 01-N-0139, Evaluation
and Treatment of Patients with Epilepsy. Patients confirmed to have medically intractable
epilepsy will be offered standard invasive and non-invasive diagnostic and surgical
procedures. Diagnostic invasive monitoring with intracranial electrodes for further
localization of their seizure focus may be required. The ultimate goal is to surgically
remove or modify the epileptic focus. Standard procedures to be performed are 1) anterior
temporal lobectomy or 2) amygdalohippocampectomy for temporal lobe epilepsy, 3) focal
cortical resection for epilepsy that arises outside the temporal lobe, 4) removal of brain
lesions causing epilepsy, and 5) multiple subpial transection.

In patients in whom invasive monitoring is medically necessary, neurophysiologic activity
during cognitive tasks will be captured from intracranial surface and depth electrodes.
Analysis will focus on the role of neuronal firing and aggregate neural activity 1) during
cognitive function, 2) in other states such as wakefulness and sleep, and 3) during periods
of time surrounding seizure activity.

Patients will be followed for two years after the surgical procedure and will receive
standard neurological examinations and MRI evaluation of the brain. Participants in this
protocol will be evaluated for potential eligibility for other NINDS clinical trials.

Outcome Measures

The primary outcome measure is the change in seizure frequency, as measured by the Engel
scale before and 1 year after treatment. Secondary outcome measures include 1) percentage
of patients who are able to be completely withdrawn from anti-epileptic medication; 2)
percentage of patients who are seizure-free (Engel Class I); 3) mean Engel Class one year
after surgery stratified by the type of surgical procedure; 4) percentage of patients with
permanent neurological side-effects from surgical treatment; 5) incidence of serious
complications of epileptic seizures, and 6) neurophysiological correlates of cognitive
function.