What is Frontal Epilepsy in Children?
Frontal epilepsy is a chronic disease of the brain, accompanied by secondary convulsive seizures, loss of consciousness and personality changes. The form of frontal epilepsy is found in 15-20% of sick patients. Pathological foci are localized in the frontal lobes due to their primary lesion. The disease can occur at any age. Onset may be delayed, and may coincide with the course of the pathological process in the brain.
Causes of Frontal Epilepsy in Children
Epilepsy of the frontal lobe occurs due to injuries, arteriovenous malformations, focal atrophy, tumors, neuroinfections and disorders of neuronal migration or dysgenesis.
Pathogenesis during frontal epilepsy in children
An epileptic seizure with this form can manifest itself in short attacks or long, in which the child can be unconscious for more than half an hour.
Simple, complex (psychomotor) partial and secondary generalized seizures are characteristic of frontal epilepsy. Psychomotor frontal attacks are most often observed. Frontal epilepsy is localized in the additional motor zone, which is opercular and dorsolateral in the motor cortex. However, it is extremely difficult to determine the precise localization of the epileptogenic zone in the frontal lobe clinically and even with the use of special research methods.
Symptoms of Frontal Epilepsy in Children
Frontal epileptic seizures are characterized by considerable variability of clinical manifestations. The disease is characterized by a sudden onset (often without an aura), a series of attacks, an extremely short duration (30–60 s), often at the same time consciousness remains (sometimes patients are able to fully describe or demonstrate their attacks), vocalization, severe, artsy motor phenomena (pedaling , chaotic movements, complex gesture automatisms), rapid secondary generalization, the absence of provoking factors.
Analysis of clinical symptoms allows to reliably distinguish three types of frontal attacks: simple partial motor paroxysms; psychomotor frontal attacks and seizures emanating from the additional motor area.
Simple partial motor paroxysms are manifested by one-sided convulsive twitching of mimic muscles, less often by convulsive twitching of the hand, and even more rarely by extremities. Focal clonic seizures are more often localized in one part of the body (face, hand, foot, arm, leg) or, more rarely, spread to other areas of the motor cortex with sequential involvement of various parts of the body – an “epileptic march.” Sometimes after an attack, Todd’s paralysis is observed for some time (paralysis, which manifests itself in the post-epileptic period after a focal or secondary epileptic seizure. It can persist for up to a day and contributes to determining localization).
Tonic postural and adverse seizures are characterized by the predominant involvement of the upper extremities (abduction and lifting the arms upward with a clenched fist), tonic turning of the head and eyes, and often tonic leading of the upper and lower extremities on both sides. In most cases, there is abduction of the head and eyes to the contralateral side.
Simple motor paroxysms are often accompanied by secondary generalization. In some cases, generalization occurs so quickly that neither the patient nor the others do not notice the partial motor onset of the attack, and only the video monitoring of the attack makes it possible to isolate the partial onset.
Psychomotor seizures (emanating mainly from the middle sections of the frontal lobe) are characterized by shorter duration (30-60 s), higher frequency (up to 10 per day – cluster flow), partial impairment of consciousness, and the absence or minimal post-offensive confusion.
A variant of the psycho-morbid attack is the frontal pseudoabsans with short-term disturbance of consciousness, arrest of speech, interruption of motor activity, gestural automatisms, sometimes tonic turning of the head and eyes.
Attacks emanating from the additional motor zone, occupy a special place among the frontal paroxysms, often mistakenly diagnosed as psychogenic seizures. The attacks are characterized by the preservation of consciousness or its partial violation. The attack can be preceded by a somatosensory aura. The dominant clinical symptoms of an attack are topical motor phenomena and automatism. Typical localization of tonic motor phenomena in the proximal upper and lower extremities. Limbs take fancy protective poses, one-sided or bilateral, there may be a typical “fencer pose”, tonic turn of the head and eyes. Automatisms are manifested by clapping hands, wheel-like rotation of the whole body (rhythmic movements of the pelvis, pedaling movements of the legs). The phonatory symptoms are represented by speech stoppage or vocalization (screaming, howling sounds), there may be laughter.
Diagnosis of Frontal Epilepsy in Children
Several methods are used to diagnose frontal lobe epilepsy: analysis of mental and neurological symptoms, neuroradiological diagnostics, computed tomography, angiography, nuclear magnetic resonance, electroencephalography.
EEG (electroencephalography) of the frontal lobe is considered only an auxiliary method. Defines the localization of foci. When recording EEG, provocative tests are used (hyperventilation, photostimulation). Routine EEG has extremely low sensitivity due to the limited ability to register epileptic activity in the frontal lobe by means of surface electrodes. In the interictal period, epileptic patterns on the EEG may be absent or adhesions and acute waves of frontal localization, one-sided or bilateral, are noted. The diagnostic value of an EEG increases when recording after a sleepless night or during sleep. When night paroxysms registration of EEG during sleep is absolutely necessary. Paroxysms occur predominantly in the second stage of slow sleep and are characterized by the presence of acute and slow wave bilateral complexes in the frontal areas. Comparison of EEG data and video recording of a seizure is the optimal method for determining the disease (combined EEG and video monitoring).
MRI and CT (to exclude local pathology of the brain) are absolutely mandatory studies for the first-time attacks of frontal epilepsy. The diagnostic significance of MRI for the exclusion of a topical neurological disease is extremely high, and therefore each patient should be administered once with suspected attacks of frontal epilepsy.
In addition to the above studies, differential diagnosis is applied. It is carried out when examining patients in order to exclude cerebral processes.
Symptomatology in the form of tonic and postural activity, increased motor activity, complex gestural automatism, vocalization, short duration, lack of slight confusion. It is very difficult to distinguish such symptoms from psychogenic diseases. Therefore, the final diagnosis can only be made after video and teleencephalographic monitoring. Often, attacks of frontal epilepsy are taken for vegetative-visceral seizures and syncope, related to anoxic (anoxoischemic) seizures.
Treatment of Frontal Epilepsy in Children
Treatment of frontal epilepsy is aimed at completely getting rid of epileptic seizures. Frontal epilepsy is one of the most difficult forms for therapy. Drugs, drug treatment and dosage are selected individually. For treatment, carbamazepine, volproate, hexamidine, difenin are used. The drugs are aimed at reducing the excitability of the nerve cells of the brain, which allows the brain to function normally. If monotherapy does not achieve results, then polytherapy is used — the use of 2 or more of the above medicines at the same time — as well as symptomatic therapy. Even after the cessation of attacks, children continue to take drugs for another 2 years. Only in extreme cases is the surgical method of treatment used. It is resorted to only when there is a large number of epileptic seizures, the ineffectiveness of drug treatment, focal seizures. After removal of the lesion causing seizures, the patient completely gets rid of them. The operation can be assigned to a child at any age – be it a baby, a child of preschool or school age. The younger the child, the easier it is to move the operation.
The prognosis depends on the localization of the lesion in the frontal lobe, structural brain damage and early diagnosis. Frequent bouts worsen social adaptation of patients, so it is very important to start timely examination and immediate treatment.
Prevention of Frontal Epilepsy in Children
In order to prevent frontal epileptic seizures, doctors recommend:
- spend more time in the fresh air, go hiking;
- observe the optimal mode of rest and work (assignments in kindergarten, school, household duties);
- light physical exertion;
- full sleep;
- a balanced diet, the introduction of a greater amount of dairy products in the diet;
- exclusion of tonic drinks (tea, coffee), overeating;
- compliance with the temperature regime – do not freeze and overheat;
- exclusion of stressful situations.