Topics and Speakers Frank G. Gilliam, MD, MPH
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Synopsis
Epilepsy and its treatment have long presented challenges to both the clinician and the researcher. As Dr Frank G. Gilliam argues, epilepsy typifies many of the difficulties in studying the brain because the disorder's complexity makes it difficult to target the abnormal processes without adversely affecting normal brain function. This lecture focuses on the neurophysiologic and neuropathological problems within epilepsy; different treatment strategies, especially pharmacological treatment; and the underemphasized comorbidity of other disorders to epilepsy, such as the high prevalence of depression among those with epilepsy.
Dr Gilliam reviews the history of epilepsy surgery and pharmacological treatments. Landmark surgery cases include Jasper and Penfield. He describes current drugs, such as carbamazepine, phenytoin, phenobarbital, and valproid. Unfortunately, although this set of drugs comprises a majority of prescriptions for epilepsy are for this set of drugs, many of them have also been shown to have unsatisfactory therapeutic outcomes.
Although epilepsy surgery is highly effective, there is great reluctance in the neurological community to refer patients for epilepsy surgery. On average, a patient needs to suffer recurrent seizures for 20 years and fail approximately six drugs before they receive a referral to an epilepsy surgery center. The ineffectiveness of medication, coupled with the effectiveness of surgery leads Dr Gilliam to strongly urge neurologists to reconsider their reluctance to recommend surgery.
The issue of consciousness during seizures is a major clinical consideration. Dr Gilliam starts by explaining the neurobiology and the neuroanatomy of consciousness during seizures. Consciousness is lost, Dr Gilliam asserts, when a seizure spreads to a subcortical region, causing inhibition of the reticular activating system (RAS) or other regions that subserve awareness. On the other hand, if the seizure only activates a region of the cortex, awareness will not be lost.
Psychiatric comorbidity, especially depression, is common in epilepsy. One recent study found that 25% of subjects with epilepsy also had significant depression and 50% had anxiety. The suicide rate is also high among those with epilepsy. There appears to be bidirectional relationship between the two disorders: those with a history of major depression have a dramatically increased risk of subsequent spontaneous unprovoked seizures. Dr Gilliam offers theoretical hypothesis about the mechanisms linking depression and epilepsy. For example, the stress response during seizure leads to cortisol activation corticotropin-releasing factor, adrenocorticotropic hormone, and cortisol activation during seizures. Dr Gilliam concludes his lecture with a brief review of neuroimaging of depression in epilepsy.
He also offers a note of hope: epilepsy care will improve as research leads to improved understanding of seizures, mood disorders, cognitive problems, and medication toxicity. In all cases, treatment should aim to minimize the patient's suffering by attending to the behavioral and subjective experiences of epilepsy.
