Epilepsy is a chronic neurological disorder characterized by recurrent seizures.1,2 Seizures are episodes of sudden, transient disturbances in cerebral excitation that occur when a sufficient number of cerebral neurons begin to fire rapidly and in synchronized bursts.3 Depending on the type of seizure, neuronal activity may remain localized in a specific area of the brain, or it may spread to other areas of the brain. In some seizures, neurons in the motor cortex are activated, leading to skeletal muscle contraction via descending neuronal pathways. These involuntary, paroxysmal skeletal muscle contractions seen during certain seizures are referred to as convulsions. However, convulsions are not associated with all types of epilepsy, and other types of seizures are characterized by a wide variety of sensory or behavioral symptoms.
Epilepsy is associated with the presence of a group or focus of cerebral neurons that are hyperexcitable, or “irritable.” The spontaneous discharge of these irritable neurons initiates the epileptic seizure. The reason for the altered excitability of these focal neurons, and thus the cause of epilepsy, varies depending on the patient.4,5 In some patients, a specific incident such as a stroke, tumor, encephalopathy, head trauma, or other CNS injury probably damaged certain neurons, resulting in their altered threshold.6–9 In other patients, the reason for seizures may be less distinct or unknown, perhaps relating to a congenital abnormality, birth trauma, or genetic factor.10–12 A systemic metabolic disorder such as infection, hypoglycemia, hypoxia, or uremia may precipitate seizure activity.13–15 Once the cause of the seizures is identified in this last group of individuals, the epilepsy can often be treated by resolving the metabolic disorder.
The exact prevalence of epilepsy is difficult to determine and varies considerably from country to country and when different criteria and survey techniques are used to assess people with epilepsy. Nonetheless, it is estimated that about 3 percent of the U.S. population that lives to 80 years of age is diagnosed with epilepsy, making this one of the most common neurological disorders.1
Because epilepsy is rather prevalent, you will frequently encounter patients with this disorder. Likewise, you will see many patients with specific conditions such as traumatic brain injury, stroke, and cerebral palsy that increase the likelihood that they will have seizures. You must adjust their treatments accordingly to try to prevent the seizures. Moreover, a patient may have a seizure during a rehabilitation session, and you should understand how to deal with it. Seizures are a common and important comorbidity that affects your ability to work with patients who have epilepsy or other seizure disorders.
Although some innovative approaches using surgery, neural stimulation, and dietary control have been reported,16–19 drug therapy remains the primary method for treating epilepsy. In general, antiepileptic medications are successful in eliminating seizures in 50 percent of ...