temporal lobe epilepsy
Introduction
Introduction to temporal lobe epilepsy The sacral epilepsy caused by the basal epilepsy in the anterior temporal lobe is called temporal lobe epilepsy and is the representative of localized epilepsy. Temporal lobe epilepsy is characterized by a simple partial seizure, usually a partial seizure and a secondary systemic episode or a mixture of these episodes. A history of fever and family history is common, and memory defects may occur. In metabolic imaging studies (eg, PET), low-area metabolism is often observed, with unilateral or bilateral temporal lobe spikes often present on EEG. basic knowledge The proportion of illness: 0.001%-0.003% Susceptible people: mainly in young people Mode of infection: non-infectious Complications: memory impairment
Cause
Causes of temporal lobe epilepsy
Perinatal factors and childbirth factors (20%):
Recently, many factors in the perinatal period and diseases during childbirth have been regarded as high risk factors for temporal lobe epilepsy. In particular, the metabolic changes of the newborn and the placenta are separated into the new environment, and brain damage may occur during the birth canal.
Epileptic seizures (20%):
Pediatric seizures in children are considered to be the most common cause. Human temporal lobe lesions are mostly localized and unilateral, while deciduous lesions caused by febrile seizures and birth injuries in children are mostly extensive and bilateral.
Scars and infections caused by traumatic brain injury (15%):
Cerebral scars, intracranial infections, hypoxia, and brain atrophy caused by degenerative diseases can be the cause of brain trauma.
Tumor (10%):
Brain tumors and other space-occupying lesions.
Pathogenesis
In the hook back of the temporal lobe, the hippocampus, the hippocampus and the amygdala have sclerosing changes. In the past, it was thought that the epileptic foci of the temporal lobe epilepsy was in the hippocampus, and the pathological evidence of a large number of temporal lobe epileptic resections proved that the hippocampus is only the temporal lobe. Part of the affected, in addition to the discovery of hippocampal sclerosis, small vascular lesions of the temporal lobe, microscopic abscess or tumor, local atrophy, scar and glial hyperplasia, neuronal degeneration and so on.
Prevention
Temporal lobe epilepsy prevention
Patients and their families must treat the disease correctly, build confidence in the fight against disease, maintain optimism, avoid anger and emotional stimulation, and eliminate fear and inferiority.
Do not drink strong tea, coffee and exciting drinks. Non-smoking, wine. Because of sudden loss of consciousness during seizures, you should choose an appropriate occupation. It is not appropriate to operate the machine, drive, wading, ascending, touching electrical appliances, poisons, and inflammable and explosive materials.
Complication
Temporal lobe epilepsy complications Complications
Idiom hemianopia may occur after temporal lobe resection, and should be avoided as much as possible. The basal part of the left temporal iliac crest has memory influence, which should be observed for a long time.
Symptom
Common symptoms of temporal lobe epilepsy common symptoms aggressive behavior irritability illusion auditory hallucinatory ambulatory automatic disorder personality disintegration automatic disease epilepsy associated with neurosis
Temporal lobe epilepsy mainly occurs in young people, and 62% of patients have their first episode before the age of 15 years. The clinical symptoms are the most common with psychomotor seizures and large hair, but small seizures and mixed episodes can also be seen. Some people have temporal lobe epilepsy. Clinical manifestations are divided into 6 major seizure types, namely:
1 sensory (auditory, taste, smell illusion);
2 emotional (irritability, anger, aggressive behavior, fear, fear, arrogance, suicidal idea);
3 self-discipline (abdominal, heart);
4 memory disorders (forgotten, hallucinations, illusions, miss the past);
5 automatic symptoms or psychomotor episodes (pharyngeal, oral, simple or complex movements);
6 consciousness of obscurity (insanity, etc.), in the observation should pay attention to the aura of attack, about 3 / 4 temporal lobe patients with various precursors, in addition to auditory hallucinations, magical smell, personality disintegration, deja vu status, lack of any Autonomous movements of purpose can be seen, excitement, euphoria, aggressive behavior, violent emotions, anger and fear, arrogance, and episodes of mental disorder. Memory impairment should be treated in the same way as psychomotor seizures. When epilepsy is located in the left temporal lobe, it is often accompanied by illusion. The automatic symptoms of hearing, forgetting and complex movements; when the epileptic foci are located in the right temporal lobe, the main manifestations are perceptual seizures and disintegration of personality, and memory impairment is mostly in the left temporal lobe.
Examine
Examination of temporal lobe epilepsy
The following examinations can be performed during temporal lobe epilepsy:
1. Structural imaging examination
Structural neuroimaging assessments include CT, MRI, MRS, fMRI, etc., which are the most commonly used methods today to detect the presence and location of structural brain lesions. CT can detect significant structural lesions such as tumors. , AVM, calcification, atrophic lesions, etc., but MRI is more sensitive than CT diagnosis of temporal lobe epilepsy, not only can detect tumors, hamartoma, cavernous hemangioma, as well as cortical dysplasia and temporal sclerotherapy - hippocampal sclerosis, MRI can detect 90% of the medial temporal lobe sclerosis, and the T2 weighted image or FLAIR image on the coronal image shows an increase in the medial temporal lobe. The T1-weighted image clearly shows the hippocampal atrophy of the temporal lobe, and the MRI hippocampal volume is measured. It can more accurately detect hippocampal atrophy, and has high specificity and sensitivity. It can accurately locate 76% to 93% of hippocampal sclerosis patients. It is the most intuitive method for diagnosing medial epilepsy of temporal lobe. Chinese normal value of hippocampus: The right hippocampus is 2.95cm3±0.3cm3 (the lower limit is 2.62cm3); the left hippocampus is 2.8cm3±0.3cm3 (the lower limit is 2.48cm), but the hippocampus volume should be carefully observed if it is at a critical value or when there is no obvious abnormality in volume. FLAIR T2WI Like the hippocampus signal changes, when the hippocampus gliosis, which may reduce the volume, and showed significantly higher signal, the MRS is the only non-invasive in vivo imaging method of displaying the tissue metabolism, often measured peaks are:
1NAA (N-acetylaspartate), almost exclusively within the neuron;
2Cho (choline);
3) Cr (creatine), the latter two are higher in glial cells, which can be used as a marker of gliosis. The ratio of NAA to Cr or Cr Cho is commonly used as a criterion for judging normality. The gray matter is mostly >0.6 as the normal standard. The sensitivity of the NAA/Cr Cho value for the diagnosis of temporal lobe epilepsy is 75%-88%, which is more sensitive than MRI and PET.
2. Functional neuroimaging
Functional magnetic resonance imaging (fMRI) can help to locate the temporal lobe epilepsy and detect the location of the epileptic foci and its important functional areas of the brain. It is believed that fMRI can replace the classic carotid Amytal test to alleviate the patient's pain. The rapid development of nuclear medicine instruments has been able to display three-dimensional local cerebral blood perfusion and glucose metabolism and distribution of multiple receptors, including single photo emission computed tomography (SPECT) and positron emission tomography ( The positron emission computed tomography (PET), SPECT study confirmed that the epileptic seizures showed hypoperfusion blood flow, and the perfusion of epileptic seizures increased significantly. The patients with temporal lobe epilepsy showed abnormal cerebral blood flow perfusion in 97% of the episodes. PET commonly used brain metabolic imaging -18F-FDG to determine the regional cerebral glucose metabolism rate, in patients with temporal lobe epilepsy, 70% to 80% of patients, the unilateral temporal lobe glucose rate decreased during the interictal period, the episode was high metabolic state This method is considered to replace the application of deep electrodes and cortical ECoG, but the low metabolic range seen by PET is generally larger than the actual lesion range. It is a non-invasive method of examination, it is a high-tech technique of molecular nuclear medicine, and can be used to directly locate epileptic foci through three-dimensional reconstruction, especially for epilepsy with negative structural imaging. It should be consistent with the results of electrophysiological examination, and the location reliability of the epileptic focus is large.
3. EEG examination (EEG)
It is the main means of determining the position of the disease. The diagnosis rate of the general scalp electrode can only be diagnosed in 1/4 patient, so the pharyngeal or sphenoid electrode should be added to improve the accuracy of diagnosis. For patients with temporal lobe epilepsy EEG repeated examinations including episodes and seizures, before and after withdrawal, sleep or no sleep, will further improve the diagnosis rate, and record the abnormal wave of temporal lobe epilepsy found by EEG in the shallow sleep state of temporal lobe epilepsy. It can be increased by up to 80% compared to the awake state.
The abnormal discharge activity of the temporal lobe on both sides of the temporal lobe lesion has been reported frequently, which is mainly caused by the diffusion of the hippocampus through the edge system loop discharge. In this case, how to determine the epileptogenic side is necessary for surgical treatment. If both sides of the temporal lobe have a discharge, the epilepsy discharge should disappear after 200 mg of isopentabarbital is injected into one carotid artery, while the other side continues to exist, and the other side of the carotid artery is injected with isopentabarbital. The same test was carried out. When the diseased side was injected, the epileptic discharges on both sides disappeared. However, after the contralateral injection, only the ipsilateral side disappeared. This is the mirror side. Recently, some people used deep buried electrodes to place the electrodes. Entering the amygdala and hippocampus for long periods of time (days to weeks) provides the most valuable results.
Preoperative EEG assessment is still the most important method for epilepsy diagnosis and epilepsy localization. Due to the rapid development of EEG technology, some have high anti-interference ability, high precision for epileptic focus, video surveillance and digital images. Frame synchronization, on-screen acquisition and playback, the analysis system's paperless EEG has been able to meet the clinical needs, which is undoubtedly convenient for neurosurgeons, but conventional EEG examination and analysis still require EEG physicians. It is extremely important to pay attention to the EEG examination of patients with temporal lobe epilepsy. It is extremely important for patients with temporal lobe epilepsy to monitor video EGEG before surgery. Determining epileptic foci is an important and important examination. In addition, in preoperative evaluation, in some cases (when epilepsy is difficult to locate), minimally invasive intracranial electrode implantation is required to record EEG. Activity, clear location of the epileptogenic area, such as implantation of a deep electrode (by stereotactic surgery), or implantation of a spike electrode in the epidural, or implantation of a strip electrode or mesh electrode under the dura mater, should have Selectively adopt this Check, accurately measure the extent of epileptic focus and its seizure, and record the electrical activity (ECoG) of the cortical surface of the brain directly with the electrode during the perioperative period (ie during the craniotomy) and directly insert the deep electrode into the sputum by hand. Almonds in the deep leaves, hippocampus structure recorded the presence or absence of epileptic activity, in addition to the clear epileptic neurons, but also to understand the boundaries of surgical removal of epileptic brain tissue.
The temporal scalp EEG of temporal lobe seizures can be expressed as follows:
(1) No abnormality.
(2) Mild or significant asymmetry in background activity.
(3) leaf spikes, sharp waves and/or slow waves, unilaterally or bilaterally synchronized, but may also be out of sync, these anomalies are not always limited to the sacral zone.
(4) In addition to scalp EEG abnormalities, intracranial tracing can more accurately detect intracranial distribution of abnormal interictal episodes.
Diagnosis
Diagnosis and diagnosis of temporal lobe epilepsy
diagnosis
According to the patient's medical history and clinical manifestations, a preliminary diagnosis can be made. EEG is still the most important method for epilepsy diagnosis and epileptogenic focus.
Differential diagnosis
It is necessary to distinguish from epilepsy that may be caused by tumors, infections or vascular malformations in the temporal lobe, and imaging findings may help to make a definitive diagnosis.
