temporal lobe epilepsy

epilepsy

[ep´ĭ-lep″se] paroxysmal transient disturbances of nervous system function resulting from abnormal electrical activity of the brain. Epilepsy is not one specific disease, but rather a group of symptoms that are manifestations of any of a number of conditions involving overstimulation of nerve cells of the brain. The estimated incidence is 0.5 per cent of the population, making this a relatively common disease. Over 70 per cent of patients have their first attack (or seizure) either during childhood or after age 50. The type of seizure varies with age of onset. Types. There are several methods for classifying types of epilepsy. On the basis of origin, it may be either idiopathic (cryptogenic, essential, genetic) or symptomatic (acquired, organic). Symptomatic epilepsy has a physical cause, such as a brain tumor, injury to the brain at birth, a wound or blow to the head, or an endocrine disorder.
One classification of epileptic seizures, called the Clinical and Electroencephalographical Classification of Epileptics of the International League Against Epilepsy, identifies four main types: (1) partial seizures, including those that begin locally, which are subdivided into (A) partial seizures with elementary symptomatology, (B) partial seizures with complex symptomatology (those with impairment of consciousness only, psychomotor symptomatology, and psychosensory symptomatology), and (C) partial seizures that are secondarily generalized; (2) generalized seizures that are bilaterally symmetrical and without local onset; (3) unilateral seizures (those involving only one hemisphere); and (4) other unclassified epileptic seizures.Types According to Symptoms. The manifestations of epilepsy depend on the area of the brain where the abnormal discharge occurs. Simple partial seizures, called also focal seizures, result from a localized cortical discharge. The symptoms may be either motor, sensory, autonomic, or any combination of the three. Complex partial seizures, as in psychomotor (temporal lobe) epilepsy, usually, but not always, originate in the temporal lobe of the brain, often with a preceding aura. As the name implies, there are many different cognitive, affective, and psychomotor symptoms. There is either loss or alteration of consciousness when the seizure begins, and afterwards the patient may feel drowsy or confused.
An attack of petit mal (absence) epilepsy lasts only a few seconds and has sudden onset with no aura or warning and no postictal symptoms. Seizures of this type usually affect children between the ages of 5 and 12 years and may disappear during puberty, but they can continue throughout life. There typically is a twitching about the eyes or mouth, the patient remains sitting or standing, and appears to have had no more than a lapse of attention or a moment of absent-mindedness.
An attack of grand mal (tonic-clonic) epilepsy usually begins with bilateral jerks of the extremities or focal seizure activity. There is loss of consciousness and both tonic and clonic type convulsions. The patient may be incontinent during the attack and there is danger of tongue biting. In the postictal phase the patient is confused and drowsy.
Atonic or akinetic seizures are characterized by loss of body tone that can produce nodding of the head, weakness of the knees, or total collapse and falling. The patient usually remains conscious during the attack.Diagnosis. A complete assessment of the patient's status is necessary, including a medical history, physical and neurological examination, and laboratory studies of the blood and spinal fluid. The latter are especially useful in determining whether an infection is the cause of the seizures. A CT scan may demonstrate a causative lesion. The diagnosis is confirmed by an electroencephalogram, which is helpful in locating the site and possibly the cause of the seizures. Treatment. Medical management with anticonvulsant drugs is the preferred therapy for about 95 per cent of patients with epilepsy. Surgical intervention for the remaining 5 per cent involves removal of the portion of brain tissue believed to be responsible for the seizures. Because of the dangers inherent in the surgery, this mode of therapy is reserved for those patients who do not respond to medical management and in whom the focus of seizure activity is accessible.
The major antiepileptic drugs are phenytoin (Dilantin), which is usually the drug of choice, phenobarbital, primidone (Mysoline), carbamazepine (Tegretol) for complex partial tonic-clonic seizures, and ethosuximide (Zarontin) and clonazepam (Klonopin) for absence seizures. Valproic acid (Depakene) is also used in the treatment of absence seizures. The choice of drug and calculation of optimal dosage is very difficult and highly individualized.
All of the anticonvulsant drugs can produce unpleasant side effects. They include gingival hyperplasia, rash, and, in the case of Dilantin, fever and leukopenia. Physical dependence can become a problem in patients taking phenobarbital or primidone, which is largely converted to phenobarbital in the blood stream. Toxic side effects are also common and include drowsiness, ataxia, nausea, sedation, and dizziness. The untoward effects of anticonvulsant drug therapy require close monitoring of the patient's response to therapy and regulation of dosage as indicated. Patient Care. Emergency care of the patient having a seizure includes clearing the immediate area to protect the patient and others, administering 100 per cent oxygen by face mask, and intravenous administration of antiepileptic medication. No one should force an object into the patient's mouth to hold it open (such as a comb, bite block, or wallet), as such objects might obstruct the airway. Do not attempt to restrain the patient, as that may cause harm to both the rescuer and the patient.
Until a diagnosis of epilepsy is confirmed, observations made before, during, and after each of the seizures can provide important information to the diagnostician. Such data also can help prepare an effective plan of care for managing the seizures once a definitive diagnosis is made.
Just before a seizure (the preictal stage) the patient may experience an abnormal somatic, visceral, or psychic sensation called an aura. The presence or absence of the aura and its nature (if it is present) should be noted and recorded. If a patient does experience a particular kind of aura just before each seizure, this information can be useful when planning care for prevention of injury. It also is helpful to note what the patient was doing just before the seizure began. If a particular emotional event or environmental or physiologic condition is found to trigger the seizures, the patient might be able to use this information to avoid or minimize the recurrence of seizures.
During the interictal stage (while the seizure is occurring) significant data include the time the seizure begins and its duration; where in the body the seizure begins and what parts of the body are involved; whether the head or eyes turn to one side and, if so, to which side; whether there is incontinence of urine or stool, bleeding, or foaming or frothing at the mouth; effects of the seizure on the vital signs; and changes in skin color or profuse perspiration.
During the postictal period the patient is assessed for lethargy, confusion, impaired speech, and reports of headache or muscle soreness.
The successful long-term management of epilepsy requires coordinated effort on the part of the patient, family, and health care professionals. Patient and family education and support are essential components of any plan of care. Epileptic patients must take their prescribed medications on their own and actively participate in the management of their illness. They and those upon whom they are dependent (as in the case of children) must know the nature of the illness, the purpose and expected effects of treatment, the side effects of the drug they are taking and its potential for interaction with other drugs that could inhibit or enhance its anticonvulsant action, and the signs and symptoms of drug intolerance that should be reported to the physician or nurse.
Education should also include information about possible seizure triggers and ways in which they might be avoided. Alcohol is especially dangerous for epileptic persons because most antiepileptic drugs are sedatives and cardiopulmonary depressants. The combination of drug and alcohol could cause loss of consciousness or even death. Moreover, alcohol acts as a seizure trigger in some persons.
It is important that patients with epilepsy wear some form of medical identification. In spite of efforts to educate the general public about the nature of epilepsy and its effects on those who have it, there remains some social stigma attached to epilepsy. Therefore, many patients do not want their friends, classmates, or employers to know they have the disease. Efforts must be made to improve the self-esteem of these people. Local chapters of the Epilepsy Association of America offer programs and opportunities for social interaction and group support to help persons with epilepsy and their families deal with the psychosocial effects of the disease. Information and guidance to a local chapter can be obtained by contacting the Epilepsy Association of America, 111 W. 55th St., New York, NY 10019.
The Epilepsy Foundation of America, 4351 Garden City Dr., Suite 406, Landover, MD 20785, supplies information on all aspects of epilepsy and can refer patients and their families to specialists and clinics in their locality.
One of the major challenges to persons working in the health field and concerned with the care of patients with epilepsy is the dispelling of myths and superstitions about the disease and the propagation of accurate information. Most persons with epilepsy can lead normal lives with few restrictions, but many are subjected to unfair employment practices and social stigma because of prejudices resulting from the general public's ignorance of the effects of epilepsy.absence epilepsy petit mal epilepsy.audiogenic epilepsy reflex epilepsy brought on by sound.grand mal epilepsy a form attended by loss of consciousness and convulsive movements, as distinguished from petit mal epilepsy. See epilepsy.jacksonian epilepsy a form of epilepsy characterized by unilateral clonic movements that start in one group of muscles and spread systematically to adjacent groups, reflecting the march of the epileptic activity through the motor cortex. myoclonus epilepsy any form of epilepsy accompanied by myoclonus; one type is Lafora's disease.petit mal epilepsy a relatively mild type of epilepsy in which the person loses consciousness only momentarily, in contrast to grand mal epilepsy; called also absence epilepsy. See epilepsy.photogenic epilepsy reflex epilepsy brought on by flickering light.psychomotor epilepsy temporal lobe epilepsy.reflex epilepsy epileptic seizures occurring in response to sensory stimuli (tactile, visual, auditory, or musical).temporal lobe epilepsy a type manifested by impaired consciousness of variable degree, with the patient carrying out bizarre but coordinated movements; called also psychomotor epilepsy. See epilepsy.

tem·po·ral lobe ep·i·lep·sy

a localization-related epilepsy with seizures originating from the temporal lobe, most commonly the mesial temporal lobe. The most common pathology is hippocampal sclerosis. Synonym(s): uncinate fit

temporal lobe seizure

A simple or complex seizure caused by abnormal electrical activity in the temporal lobes, which may result in transient changes in movement, sensation, autonomic function, alertness and awareness.

Clinical findings
Temporary paralysis, sleep paralysis, fear sensation, hallucinations (e.g., delusion of lycanthropy, or misinterpreted as UFO abductions). Temporal lobe seizures may occur in anyone at any age, as a single episode, or as a chronic seizure disorder.

Diagnosis
Abnormal electrical activity on EEG.

Aetiology
Temporal lobe damage (trauma, hypoxia), ischaemia and/or infarction, tumours, infection or any other discrete lesion.
Management
Phenytoin, phenobarbital, carbamazepine, valproate.