What Is Frontal Lobe Epilepsy?

Frontal lobe epilepsy with characteristics of simple partial seizures, complex partial seizures, and secondary generalized seizures or a mixed seizure of these seizures is called frontal epilepsy. Frontal lobe epilepsy accounts for 20% to 30% of all types of partial epilepsy. Frontal lobe epilepsy is characterized by simple parts, complex parts, secondary systemic attacks, or a mixture of these attacks. Seizures usually occur several times a day and often occur during sleep. Status epilepticus is a common comorbidity.

Basic Information

English name: frontal lobe epilepsy
Visiting department: Internal medicine
Common causes: Genetic, unexplained abnormal discharge

Common symptoms: Systemic tonicity-loss of consciousness immediately after the onset of clonic seizures; clear and progressive consciousness, pauses, mental disturbances, etc.

Causes of frontal lobe epilepsy

The frontal lobe includes the primary motor cortex, the premotor cortex, the prefrontal cortex, and the marginal and lateral marginal cortex. These areas may cause frontal epilepsy if abnormal discharge occurs due to heredity and some unknown reasons.

Frontal lobe epilepsy clinical manifestations

Frontal lobe epilepsy is characterized by simple partial seizures, complex partial seizures, and secondary generalized seizures or a mixture of these seizures. Seizures usually occur several times a day and often occur during sleep. Partial frontal seizures can sometimes be confused with seizures caused by mental factors, and status epilepticus is a common comorbidity. The types of attacks are described below:

Auxiliary motor area attack

Seizures in the auxiliary motor area are in the form of gestural focal tonicity with vocalization, pauses in speech, and fencing posture. The patient's head and eyes turned to the opposite side of the epilepsy origin, the upper limb abduction on the opposite side of the epilepsy focus, external rotation of the shoulder, and elbow flexion. On the ipsilateral upper and lower limbs, ankylosing abduction, the movement of the distal upper limb is more obvious than the distal lower limb. The clinical manifestation of this ipsilateral upper limb extension to the origin of epilepsy is described as "fencing posture".

2. Seizures of the cingulate gyrus

Seizures are complex and partly accompanied by complex motor gesture dysfunction at onset. Common autonomic signs such as mood and emotion changes are common.

3. Forehead polar seizures

Prefrontal polar seizures include compulsive thinking or loss of initial contact and turning movements of the head and eyes, which may be accompanied by evolution, including inverse movements and axial clonic tics and falls, and autonomic signs.

4. Orbitofrontal attack

The form of the orbitofrontal seizure is a complex partial seizure with initial motor and gestural automata, olfactory hallucinations and illusions, and autonomic signs.

5. Lateral dorsal attack

The form of the attack may be ankylosing or less common clonics with eye and head movements and speech stop.

6. Island cover attack

Features of island cover attacks include symptoms of chewing, drooling, swallowing, larynx, cessation of speech, fear of upper abdomen, and autonomic signs. Simple partial attacks, especially partial clonic facial muscle attacks, are common and may be simple Side. If secondary sensory changes occur, numbness may be a symptom, especially on the hands. Taste hallucinations are particularly common in this area.

7. Motor cortical seizures

Motor cortical epilepsy is mainly characterized by simple partial seizures, and its location is based on which side is affected and the local anatomy of the affected area. In the lower anterior Rolando area, there may be speech stop, vocalization, or speech disturbance, and rigidity on the side -Clonic movements or swallowing movements, systemic attacks often occur. In the lateral fissure area, some motor attacks are not accompanied by progressive or Jackson attacks; especially on the contralateral upper limb. When the lateral central lobules are involved, the onset shows tonic movement in the ipsilateral foot, and sometimes tonic movement in the contralateral leg. Todd is paralyzed after seizures. It usually originates in the motor cortex area and the epilepsy threshold in this area. Lower and enhanced spread to wider epileptic areas.

8.Kojewnikow syndrome

There are two types of Kojewnikow syndrome considered, one is Rasmussen syndrome, a type of epilepsy syndrome included in childhood symptomatic epilepsy, and the other is a special type that represents a partial onset of lateral fissures in adults and children Its main features are: partial seizures with clear positioning; myoclonus usually occurs at the site where somatic seizures occur; EEG shows focal paroxysm on the basis of normal background activity Abnormalities (spikes and slow waves); the syndrome can occur at any age in childhood and adulthood; the cause (tumor, vascular disease) can often be detected; the syndrome does not evolve progressively (clinical Type, EEG or psychological (except those related to the evolution of pathogenic damage), the syndrome can be caused by mitochondrial encephalopathy (MELAS).

Frontal lobe epilepsy

EEG

Because of frontal lobe seizures, bilateral frontal lobe synchronously releases scalp EEG, which is often difficult to locate, and often due to artifacts, it is difficult to explain EEG changes. The epileptic focus of frontal lobe epilepsy is often multifocal or bilateral frontal lobe foci, which also affects the accurate location of frontal lobe epilepsy. At this time, a video EEG should be performed to observe the changes in the EEG during the onset and the behavioral changes in the onset to help localization. In the preoperative evaluation of frontal lobe epilepsy, EEG is still an important method.

2. Imaging examination

Using structural and functional imaging methods, CT and MRI can find some small low-grade gliomas, AVM cavernous hemangioma, and cerebral hypoplasia, as well as meninges, brain scars, cerebral atrophy, and cerebral cystic Changes, etc., are conducive to the positioning of epileptic foci.

Frontal lobe epilepsy diagnosis

Frontal lobe epilepsy can be diagnosed if one of the following 6 characteristics is present:

1. Generalized tonic-clonic seizures are immediately lost of consciousness.

2. In the early stages of seizures, the head and eyes turn to the opposite side, followed by generalized seizures. Loss of consciousness after the seizure often indicates that the epileptic focus is located in the anterior 1/3 of the frontal lobe.

3. Initially, the head and eyes turned to the opposite side of the lesion, and the consciousness was gradually and unconsciously, and then the complete loss of consciousness and generalized seizures, suggesting that the epileptogenic focus originated in the middle part of the frontal convex surface.

4. It is manifested as posture movement of a certain part of the body, such as the contralateral arm being held upright, the ipsilateral arm extending downward and the head turning to the opposite side of the lesion, suggesting that the epileptogenic focus is located on the inner side of the middle frontal lobe.

5. Often show no expression of emotion, or have a short movement pause, thinking disorder, and gaze followed by generalized seizures.

6. Seizures may have seizures or after-seizures, similar to temporal lobe epilepsy. SPECT and PET during inter seizures can confirm hypoperfusion or hypometabolism in the brain, while SPECT during seizures often show hyperperfusion of the frontal cortex, which is helpful for the localization of epileptic foci.

Patients with epilepsy diagnosed by MRI have a good effect in most cases after epilepsy surgery. For non-focal epilepsy with no positive MRI findings, the postoperative effect is not ideal.

Frontal lobe epilepsy treatment

In the preoperative evaluation, those who have the following conditions often suggest that better surgical results can be achieved: MRI images show clear lesion boundaries; epileptic EEG seizure-like discharge can be located; clinical features of seizures suggest the frontal lobe Origin; The above characteristics are consistent with each other; The lesion is visible during surgery and does not involve speech functional cortex; There are no other potential epileptic abnormalities.

Frontal lobe epilepsy surgery is commonly used to treat epilepsy and lesion resection of the cerebral cortex.