NEUROLOGY AND NEUROSURGERY - YU. V. ALEKSEENKO - 2014

EPILEPSY AND EPILEPTIC SYNDROMES

Epilepsy is a common disorder, ranking second or third among all CNS pathologies in terms of neurology outpatient visits in many countries. Global statistics indicate that epileptic seizures occur in approximately 1% of the population (accounting for patients who have experienced one or more seizures within the past 5 years). However, in some geographical regions, the prevalence of epilepsy reaches 4-5%. This high frequency in such countries is attributed to the high prevalence of neuroinfections, trauma, and perinatal CNS injuries. The prevalence of epileptic seizures differs between children and adults. For instance, febrile seizures occur in 2-5% of children under the age of 5, though this does not affect the overall prevalence rates of epilepsy in adults. Overall, the lifetime probability of developing epilepsy is 2-4%. At the same time, the probability of experiencing at least one epileptic seizure (single or accidental) approaches 8%. When considering the combined probability of developing epilepsy, single (accidental) epileptic seizures, symptomatic epilepsy seizures, and febrile seizures, it reaches up to 10% in an individual by the age of 80.

In 50-60% of cases, epilepsy develops before the age of 16. The second peak in epilepsy incidence occurs in older age. Interestingly, in Western countries, the incidence of epilepsy in the over-70 age group is higher than in children under 10. The high prevalence of epilepsy and epileptic syndromes necessitates rigorous epileptology training for emergency and general practice physicians. Neurologists, neurosurgeons, and psychiatrists encounter epilepsy and epileptic syndromes on a daily basis in their routine practice.

Etiology AND Pathogenesis. Definition of Basic Concepts

Since the primary clinical manifestation of this disorder is the epileptic (convulsive) seizure, its definition should be clarified. Common terms such as seizure, fit, crisis, spasm, or paroxysmal state merely denote sudden, short-lived, time-concentrated manifestations of various pathological conditions. The Nature of these phenomena, as well as their specific mechanisms of development, can vary widely. Only a portion of them are of epileptic origin. Differentiating between paroxysmal states of epileptic and non-epileptic origin is a complex and crucial task. Therefore, the specific nature of these disorders must be reflected in the terminology used—epileptic seizure, fit, paroxysm, etc. It must be emphasized that the term epileptiform (seizure, fit, etc.) literally denotes only a superficial resemblance to epileptic disorders and must be applied judiciously. The terms epileptic and convulsive seizure are frequently used as synonyms, although non-convulsive variants of epileptic seizures do exist within THE SPECTRUM OF paroxysmal disorders.

Finally, It is important to remember that a spasm (or convulsions) is a descriptive term that, in this context, simply refers to involuntary Muscle tension, cramping, or twitching. Epileptic convulsions (tonic or clonic) are of central origin, meaning they result from epileptic activity in various PARTS OF THE Brain. Conversely, increased excitability of peripheral neuromuscular structures can be accompanied by painful tension or cramping of the limb Muscles, sometimes leading to specific limb postures and positions (spasmophilia, tetany), which are unrelated to epilepsy. Painful cramps, tightening, or pulling of the calf muscles resulting from Peripheral Nervous system disorders are known as cramps. The well-known phenomenon of muscle shivering—chills occurring during thermal adaptation disorders and autonomic dysfunctions—reflects an imbalance in central regulation mechanisms, yet it also bears no relation to epileptic disorders.

From the perspective of specific etiological variants and mechanisms of development known to date, epilepsy is a heterogeneous pathological condition. Consequently, the plural form (epilepsies) is frequently used in recent discussions of this disorder. At the same time, the existence of common patterns in The Development of epilepsy as a disease allows it to be referred to in the singular, as is traditional in Russian-language literature, which nevertheless encompasses a wide range of epileptic conditions.

Epilepsy is a chronic, multifactorial disease of the Central Nervous System manifested by recurrent epileptic seizures resulting from aberrant epileptic electrical activity of brain Neurons. In some cases, this disorder is accompanied by the development of pathohabitudinal (personality) changes.

Currently, METABOLISM/2.html">THE CONCEPT OF the multifactorial nature of epileptic disorders is predominant. This implies that the disease may develop through a combination of genetic predisposition and various acquired CNS lesions. The critical ratio of hereditary and acquired factors likely differs among various epileptic disorders. Genetic predisposition is complex in nature. It consists of inherited characteristics in the Organization OF THE brain's electrophysiological processes, neurometabolism patterns, and neurotransmitter system activity, which determine the balance between epileptic and anti-epileptic mechanisms and, consequently, individual fluctuations in the CNS seizure threshold. For certain epileptic conditions, genes responsible for CNS functioning mechanisms associated with a high probability of epileptic reactions have been identified. Approximately 150 Gene pathology variants and A number of Chromosomal Disorders include epileptic seizures in their clinical spectrum. On the other hand, children of parents with epilepsy face an increased risk of developing the same condition (up to 6-12%).

Key to understanding the etiopathogenesis of epilepsy is the Concept of the epileptic focus. This is a population of neurons exhibiting heightened spontaneous activity and capable of generating specific high-amplitude hypersynchronous electrical discharges. Upon activation of the neurons within the epileptic focus and a weakening of anti-epileptic defense mechanisms, aberrant electrical activity can spread beyond its borders, recruiting and synchronizing The activity of neurons in neighboring brain structures. Once a sufficiently large number of neurons are incorporated into the epileptic process and a certain "critical mass" is reached, global disruptions in the brain's bioelectrical activity occur, accompanied by the onset of an epileptic seizure. During a seizure, abnormal electrical discharges facilitate the recruitment of neuronal networks across various brain regions into synchronous activity and the consolidation of pathological connections. Thus, a seizure that has occurred facilitates the development of subsequent ones. Secondary sources of epileptic activity may form under the Influence of the primary focus. All these patterns characterize The formation of the epileptic system. The spread of epileptic processes is hindered by anti-epileptic defense mechanisms, in which the reticular nuclei of the Pons, the Cerebellum, the caudate Nucleus, and other structures participate. The balance between epileptic and anti-epileptic influences depends on the baseline functional state of the CNS, hormonal fluctuations, and the action of numerous endogenous and exogenous factors (changes in atmospheric pressure and magnetic fields, psycho-emotional stress, Sleep deprivation, alcohol intoxication, colds, etc.).

The epileptic focus typically arises within an area of cortical Dysplasia or adjacent to various brain lesions—traumatic, ischemic, infectious, or toxic. Very frequently, this is not an active pathological process, but rather residual damage that is nonspecific, represented by areas of cortical atrophy or sclerosis. Groups of neurons serving as the source of epileptic discharges are usually located at the periphery of traumatic scars, cysts, or dysplasia sites. The Development of the disease occurs in two stages. The First stage—from the moment of brain injury to the occurrence of the first epileptic seizure—is the maturation phase of the epileptic focus. The Second Stage begins after the initial clinical manifestations of the disease (the first seizure) and represents the period of establishing a stable epileptic system. In generalized forms of epilepsy, the Formation of the epileptic system follows a different pattern, where nonspecific thalamic nuclei may serve as the source of abnormal rhythmic activity.

It should be noted that alongside established genetic and environmental influences that drive the development of epilepsy, there are a number of factors that under certain circumstances frequently facilitate or provoke the epileptic seizure itself. Among these triggering factors are sleep deprivation, hyperventilation, rhythmic sensory stimulation (visual, auditory, etc.), hyperthermia, alcohol, certain CNS stimulants, psycho-emotional overexertion, and others.

In epilepsy as a primary disease, epileptic seizures emerge in childhood or adolescence and constitute the core manifestation of the disorder. Meanwhile, CT or MRI scans help reveal signs of structural CNS changes in many patients, which serve merely as traces of prior CNS injuries. These may include signs of focal dysplasia or remnants of antenatal, perinatal, or postnatal CNS damage (e.g., mesial temporal sclerosis in the hippocampus, etc.). Most frequently, these are associated with viral infections, parasitic diseases (Toxoplasmosis), intoxications and Metabolic Disorders, anoxia, perinatal encephalopathy, birth trauma, and the like. Notably, Anamnesis very often lacks any mention of these pathological conditions. In such cases, it is customary to speak of cryptogenic forms of epilepsy—that is, conditions where the presence of the aforementioned structural brain lesions as risk factors for epilepsy is presumed, but cannot be proven due to the remote Nature of the events. With the increasingly widespread use of in vivo brain imaging techniques (CT and MRI), the number of cryptogenic epileptic conditions is shrinking. It is becoming evident that the majority of epileptic conditions can be classified as symptomatic epilepsy, wherein the localization of the structural brain lesion and the potential etiology of the disease can be established. In the absence of overt MRI abnormalities, a subset of patients may nevertheless be suspected of having changes related to microdysgenesis—neuronal ectopias with impaired neuronal synaptic connections, deafferentation, and neuronal hypersensitivity. In cases where obvious structural CNS changes are absent and genetic factors are presumed to play a significant role in the development of epilepsy, the term idiopathic forms is used.

Epileptic seizures occurring during acute or chronic, actively progressing cerebral diseases should be regarded as an epileptic syndrome—a variant of symptomatic epilepsy that requires special attention. An epileptic syndrome may arise during the acute phase of cerebrovascular disorders, traumatic brain injury, toxic encephalopathy, infectious and inflammatory brain diseases, and Other forms of CNS damage. Unlike epilepsy as a primary disease, in such pathological conditions epileptic seizures are typically not the sole manifestation of the illness. At the same time, at some stage of the disease's progression, the epileptic syndrome may become its leading manifestation and determine the patient's clinical state. It may serve as the primary reason for diagnostic evaluation, which ultimately leads to the Discovery of the aforementioned CNS lesions.

There is also a group of specific epileptic reactions or situation-related seizures, where an obvious cause (structural brain lesion) and an established epileptic system are absent, and the triggered epileptic seizure can be explained as the result of a combination of unfavorable circumstances (specifically, supra-threshold influences) leading to the development of such a universal brain pathophysiological reaction as an epileptic seizure. Examples include febrile seizures occurring in children against the backdrop of a sharp spike in body Temperature during colds, yet in the absence of signs indicating CNS involvement in the pathological process. Such an epileptic seizure can be regarded as "accidental," and the risk of systematic seizure recurrence in the future is minimal.

Thus, for a better understanding of The Essence of the discussed epileptic conditions, they can be somewhat conventionally differentiated into epilepsy as a disease, epileptic syndromes, and isolated epileptic seizures (accidental epileptic seizures or epileptic reactions, According to the terminology of domestic neurologists). Nevertheless, the formation of these conditions proceeds in accordance with the universal patterns of epileptogenesis. A detailed Structure/133.html">Discussion of these variants of epileptic conditions is therefore necessary to clarify the realistic opportunities for therapeutic intervention in the pathological process and to determine the fundamental approaches and management schemes for patients. In epilepsy as a primary disease, the primary objective is to prevent the recurrence of epileptic seizures. Intervening in the potential cause of brain damage is impossible, as it remains merely a fact of a remote medical history. In symptomatic forms, seizure cessation can be achieved through surgical removal of the epileptic activity source. Conversely, in epileptic syndromes, attention must be focused on treating the underlying disease and managing the acute phase of its progression. In situation-related seizures, it is sufficient to rule out other diseases and aggravating circumstances, as the prognosis is overwhelmingly favorable even without the prophylactic administration of antiepileptic drugs.

Overall, among children, the spectrum of risk factors for epilepsy and epileptic syndromes is dominated by various ante- and perinatal CNS injuries, cortical dysplasions, infections, and neurodegenerative diseases. In middle-aged and elderly individuals, the risk factors for developing epileptic syndromes are predominantly trauma, cerebrovascular diseases, alcohol abuse, and Brain Tumors. It is believed that genetic predisposition is of particularly vital importance in the development of idiopathic forms of epilepsy. Nevertheless, The Influence of this factor must also be taken into account when various epileptic syndromes and even situation-related seizures occur.

Classification of Epileptic Seizures

The principal clinical manifestations of epilepsy are epileptic seizures. Currently, they are systematized as follows.

   I. Partial (focal, local) seizures

1. Simple

   ■ Motor

   ■ Sensory

   ■ Autonomic

   ■ With mental disorders

   2. Complex partial seizures (with impaired consciousness), beginning as simple seizures but subsequently accompanied by impaired consciousness, automatisms, and mental disorders

3. Secundarily generalized partial seizures

   II. Generalized seizures (convulsive and non-convulsive)

1. Absence seizures

   ■ Typical

   ■ Atypical

1. Generalized convulsive seizures

   ■ Tonic

   ■ Clonic

   ■ Tonic-clonic

   ■ Atonic

2. Myoclonic seizures

   III. Unclassified epileptic seizures

Generalized convulsive (tonic-clonic) seizures are quite common and follow a definite sequence of stages. An epileptic seizure may begin suddenly without any external triggers or preceding sensations. The patient loses consciousness and falls, sometimes uttering a compressed cry caused by contraction of the chest muscles and narrowing of the glottis. At this very moment, the pupils dilate and become unreactive to light. The fall may result in bruises and serious injuries to the HEAD and other parts of the body. The Muscles of the Trunk and extremities tense up, the head is thrown back, the jaws lock convulsively, breathing is temporarily arrested, and the Skin and mucous membranes turn pale and then cyanotic. This is followed by jerky contractions of the limbs and trunk, noisy, raspy breathing, and foaming at the Mouth. Tongue biting may occur during the convulsive phase. The clonic seizures gradually subside, leading to a state of stupor and muscular relaxation. In this phase, the patient does not respond to external stimuli, and consciousness only clears gradually over the course of several minutes. Involuntary urination may occur. Sometimes this state transitions into a deep sleep. The seizure typically lasts 2 to 3 minutes. For some time afterward, the patient may experience lethargy, malaise, headaches, muscle aches, and joint pain. As a rule, the patient has no memory of the event. Therefore, in the absence of witnesses, a past seizure can be inferred from indirect signs: tongue biting, foaming at the mouth, involuntary urination, unusual injuries, and subsequent stupor. Occasionally, seizures are exclusively tonic or clonic in nature.

Among generalized seizures, so-called minor seizures, or absences, are also distinguished. They are most commonly observed in children. Absences manifest as sudden, brief (lasting a few seconds) losses of consciousness or staring spells accompanied by an interruption of speech and gaze, sometimes with a subtle change in facial expression, but without a fall. Upon recovery, patients have no recollection of the event and resume their interrupted activity. During an absence seizure, characteristic 3 Hz spike-wave complexes are recorded on the patient's EEG. Minor seizures can occur very frequently—up to several dozen times an hour—significantly impairing not only the child's goal-directed activity but also their ability to communicate fully. In complex absences, the seizure structure is supplemented by twitching of the facial and arm muscles, automatisms (mumbling, fumbling with objects, etc.), and falls.

Partial seizures are characterized by sensory, motor, or other phenomena of Cerebral Cortex irritation, the nature of which is determined by the localization of the epileptic focus. Partial seizures usually occur without a complete loss of consciousness. When the focus of epileptic activity is localized in the motor cortex, the partial epileptic seizure manifests as clonic twitching of the muscles of the face, arm, or leg on the contralateral side corresponding to the area of cortical irritation (Jacksonian motor seizure). When the source of epileptic activity arises in the sensory cortex, sensory partial seizures may develop with paresthesias in the face, trunk, or extremities on the contralateral side corresponding to the localization of irritation (Jacksonian sensory seizure). Partial seizures may involve forced deviation of the eyeballs, turning of the head and even part of the trunk, visual disturbances, or auditory and olfactory phenomena. Much less frequently, partial seizures present as speech arrest, complex autonomic symptom complexes, or psychiatric abnormalities. Complex partial seizures involve impaired consciousness, where the patient is aware of what is happening but unable to react to the surroundings, or conversely, is unaware of their surroundings. Patients may experience feelings of unreality, déjà vu or jamais vu, affective states of melancholy or anxiety, various automatisms, etc.

Sometimes beginning as partial seizures, they can transform into generalized convulsive seizures (secondary generalization). In such cases, patients may retain memories of events that occurred before the loss of consciousness. The partial component of such a seizure is called an aura. In any given patient, it is usually stereotyped and lasts a few seconds. Its characteristics help determine the localization of the epileptic focus. An aura can be motor, sensory, autonomic, or psychic. It may involve turning of the head, movements in the limbs and face, involuntary utterance of individual words or phrases, and simple or complex visual hallucinations (flashes of light before the eyes, unusual coloring or distortion of object contours, visual field defects). Patients may experience a feeling of déjà vu, unpleasant odors and an unusual taste in the mouth, various sounds or noise, feelings of fear, terror, or bliss, as well as discomfort in the epigastric region or The Heart area, salivation, and chills. It must be remembered that up to 40% of partial seizures appearing in adults may be caused by brain tumors and serve as their earliest sign.

In some cases, 1 to 2 days before a seizure, patients experience changes in well-being (headaches, sleep disturbances, mood swings, etc.), which are referred to as prodromal symptoms. Epileptic seizures deplete the brain's metabolic resources and cause a temporary disorganization of its Functions. This explains postictal limb paresis, speech and memory impairments, and other deficits. In some instances, the nature of the seizure does not allow it to be definitively classified into any known group (up to 15% of cases). Although extremely rare, sudden unexpected death in epilepsy (SUDEP) may occur during an epileptic seizure.

Mental disorders may occur among the clinical manifestations of epilepsy. Some of these disturbances have already been described as components of an epileptic seizure. However, in certain cases, longer periods of dysphoria and psychotic states develop. Such mental disorders, as well as personality changes in patients, are not mandatory manifestations of epilepsy. Some abnormalities may be caused by organic brain damage, of which epileptic seizures are also a manifestation. On the other hand, the epileptic reorganization of brain functions during the progression of the disease is of great importance. It is likely that in some cases antiepileptic therapy also exerts a certain influence on the patient's cognitive functions and emotional sphere.

Classification of Epilepsy

The classification of epileptic seizures must be distinguished from the classification of epilepsies (epileptic syndromes). The current international classification of epilepsies (1989) is an imperfect and presumably unfinished attempt to correlate the etiology of the disease, seizure type, presence or absence of structural brain abnormalities, probable prognosis, etc.

   I. Localized forms (focal, local, partial)

   1. Idiopathic with age-dependent onset

   ■ Benign childhood epilepsy with centrotemporal spikes (benign rolandic epilepsy)

   ■ Childhood epilepsy with occipital paroxysms

   ■ Primary reading epilepsy

   2. Symptomatic

   ■ Chronic progressive partial epilepsy (Kozhevnikov syndrome)

   ■ Epilepsy with specific seizure-triggering factors (reflex epilepsy)

   ■ Syndromes of frontal, temporal, parietal, and occipital lobe epilepsy.

   II. Generalized

   1. Idiopathic with age-dependent onset

   ■ Benign familial neonatal seizures

   ■ Benign neonatal seizures

   ■ Benign myoclonic epilepsy in infancy

   ■ Epilepsy with pyknoleptic absences (pyknolepsy, childhood absence epilepsy)

   ■ Juvenile absence epilepsy

   ■ Epilepsy with myoclonic absences (juvenile myoclonic epilepsy)

   ■ Epilepsy with generalized tonic-clonic seizures upon awakening

   ■ Other forms of generalized idiopathic epilepsy

   ■ Epilepsy with specific precipitating factors (reflex epilepsy and startle epilepsy)

   2. Cryptogenic or symptomatic forms

   ■ West syndrome

   ■ Lennox-Gastaut syndrome

   ■ Epilepsy with myoclonic-astatic seizures

   ■ Epilepsy with myoclonic absences

   3. Symptomatic forms

   ■ Early myoclonic encephalopathy

   ■ Early infantile epileptic encephalopathy with suppression-burst pattern on EEG (Ohtahara syndrome)

   ■ Other symptomatic generalized forms of epilepsy

   ■ Symptomatic generalized forms of epilepsy of specific etiology (complicating other disease states)

   III. Epilepsy and syndromes not clearly defined as focal or generalized

1. With both generalized and focal features

   ■ Neonatal seizures

   ■ Severe myoclonic epilepsy in infancy

   ■ Epilepsy with continuous spike-wave during slow-wave sleep

   ■ Acquired epileptic aphagia (Landau-Kleffner syndrome)

   ■ Other unclassified forms of epilepsy

   2. Seizures without unequivocal generalized or focal features

   IV. Special syndromes

1. Situation-related seizures

   ■ Febrile seizures

   ■ Seizures occurring in acute metabolic or toxic states

2. Isolated seizures or isolated status epilepticus

When the etiology and localization of structural brain lesions are established, epilepsy is classified as symptomatic. If the etiology cannot be precisely determined, but an organic brain lesion is evident, the epilepsy is termed cryptogenic. In the absence of overt signs of organic brain damage and with an unknown etiology, epilepsy is considered idiopathic. There are specific forms, notably situation-related seizures, such as febrile and dysmetabolic seizures.

Selected variants of epileptic conditions

Febrile seizures

Febrile seizures are typically generalized epileptic seizures occurring in children against the Background of a sharp rise in body temperature caused by colds, but in the absence of central nervous system infection or damage. Such seizures are observed in 3–4% of children aged 3 months to 6 years. In 30–40% of children, they may recur under similar circumstances. The development of febrile seizures occurs in children with a certain genetic predisposition, which has a polygenic or multifactorial nature, yet the long-term prognosis is generally favorable. The subsequent risk of developing epilepsy in such children is approximately 2–3%. This risk may increase to 6–13% in the presence of additional risk factors: seizure duration greater than 15 minutes, focal Features of the seizure, pre-existing neurological abnormalities, seizure recurrence within the first 24 hours, or a family history of epilepsy in parents, brothers, or sisters. No abnormalities are detected on EEG and MRI. In the absence of additional aggravating factors, prolonged use of antiepileptic drugs is not required.

Epilepsy and alcohol

Epileptic seizures develop in 5–15% of individuals suffering from alcoholism. Furthermore, in two-thirds of cases, seizures occur during the withdrawal period. Interestingly, more than 20% of adults with newly diagnosed epilepsy have no other risk factors for the disease except alcohol abuse. The epileptic syndrome during withdrawal can occur following varying durations of alcohol consumption and is typically caused by the sudden cessation of alcohol intake or a significant reduction in its dose. Epileptic seizures usually appear 18–24 hours after the cessation of alcohol consumption. In 60% of such patients, multiple epileptic seizures are observed. Most frequently, two to four seizures develop within the subsequent 6 hours. Status epilepticus may develop in 3% of patients. In 30% of cases, the onset of epileptic seizures is combined with the development of delirium tremens. Overall, alcoholism is associated with a threefold increase in the risk of epileptic seizures. Moreover, alcohol abuse, aside from the danger of withdrawal seizures, is an independent dose-dependent risk factor for epileptic seizures and also exerts an additional indirect effect associated with an increased incidence of TRAUMATIC BRAIN INJURIES. In addition, alcohol intoxication may act as a factor provoking the onset of epileptic seizures.

Epilepsy and traumatic brain injuries

Unlike post-traumatic epileptic syndrome, for which the critical period of formation is considered to be the first 18 months after trauma, early epileptic seizures can be observed in the acute period of traumatic brain injury (most often During the first week post-injury). They develop in 2.6% of children and 1.8% of adults. The probability of early epileptic seizures in the acute period of brain injury increases with decreasing age of the victims and increasing severity of the injury. In severe traumatic brain injuries, they occur in approximately 30% of children and 10% of adults. The presence of early epileptic seizures in patients with traumatic brain injuries increases the subsequent risk of developing epilepsy from 3% to 25% and poses a more significant danger to victims older than 15 years. The overall risk of developing late post-traumatic epilepsy varies between 9% and 42% across various studies, and is especially high in intracranial hematomas, penetrating, and gunshot head injuries. In mild traumatic brain injuries, There is a minor risk of developing post-traumatic epilepsy in the long-term post-injury period. The increase in the standardized incidence (relative to the general population values) of late post-traumatic epilepsy following traumatic brain injuries of varying severity is 1.5 for mild traumatic brain injuries (not statistically significant), 2.9 for moderate injuries, and 17.0 for severe traumatic brain injuries. The administration of antiepileptic drugs in the acute period of traumatic brain injuries does not reduce the likelihood of subsequently developing post-traumatic epilepsy. At the same time, their use in the acute period of trauma may be necessary for the Prevention of early epileptic seizures in individuals at high epileptic risk.

Epilepsy and brain tumors

Of particular note is the fact that in approximately 40% of adults with newly diagnosed focal epileptic seizures, the underlying cause is brain tumors. Low-grade tumors, predominantly in the medial Regions of the temporal lobes, are found in 10–30% of patients with long-standing temporal lobe epilepsy with drug-resistant seizures. Slow-growing brain tumors, such as meningiomas, more frequently manifest with an epileptic syndrome. The presence of epileptic seizures for several years and the absence of overt neurological abnormalities in the patient's neurological status do not rule out the development of a brain tumor. The onset of a tumor and the appearance of an epileptic syndrome are not necessarily synchronous processes, although they may share the same dysembryogenetic origin.

Diagnosis of Epilepsy

The diagnosis of epilepsy begins with clarifying the nature of the paroxysmal event. It is essential to investigate the circumstances surrounding the episode, the patient's condition immediately preceding the seizure, any potential prodromal symptoms, the clinical manifestations of the paroxysm, and the post-ictal state. Particular attention should be paid to indirect signs of a recent epileptic seizure (such as evidence of tongue biting, etc.), especially when the patient cannot recall the details of the incident or no witnesses are present. A thorough medical history—both immediate and remote—must be obtained, including a family history of similar disorders in parents or other relatives, pre- and perinatal developmental complications, febrile seizures, other medical conditions, trauma, intoxications, and psychiatric disturbances. In addition to a neurological examination, a comprehensive somatic evaluation is required, with a special focus on The Cardiovascular system.

In many cases, it is necessary to differentiate epileptic seizures from non-epileptic paroxysms. The most common among these include neurogenic syncope, somatically induced syncopal states, transient ischemic attacks, breath-holding spells in children, autonomic crises, and hypoglycemic states. One of the most challenging tasks is distinguishing between epileptic seizures and psychogenic nonepileptic seizures (pseudoseizures). Some patients may present with more than one type of seizure. Night terrors, somnambulism (sleepwalking), and nocturnal enuresis are not related to epileptic conditions. Unfortunately, clarifying the exact nature of a seizure is frequently a complex challenge that cannot always be resolved immediately, even with The Use of state-of-the-art EEG and video-monitoring Methods.

Electroencephalography (EEG) is one of the most widespread and informative diagnostic tools for various paroxysmal disorders. Characteristic patterns of epileptiform activity on an EEG include sharp waves, spikes, and spike-wave complexes. It is often possible to identify an epileptic focus, the localization of which can explain specific clinical manifestations observed during a seizure. Epileptiform activity is typically recorded during the seizure itself, but it can also be frequently captured during the interictal period. To provoke specific EEG abnormalities, functional activation Procedures (such as hyperventilation, photic, and auditory stimulation) are employed. Performing an EEG during sleep significantly increases the likelihood of detecting epileptiform discharges. Alternatively, an EEG study can be performed after 24–28 hours of sleep deprivation. It should be emphasized that "cortical irritability" or seizure readiness is strictly an electrophysiological (rather than a clinical) phenomenon. The absence of epileptiform activity on an EEG does not rule out a diagnosis of epilepsy when characteristic epileptic seizures are present. Approximately 50% of patients with epilepsy have a normal baseline EEG containing no specific abnormalities. Conversely, detecting epileptiform EEG changes in a healthy individual does not justify diagnosing epilepsy before a clinical seizure occurs. In recent years, long-term video-EEG monitoring has been utilized to clarify seizure characteristics and diagnose Various Forms of epilepsy. This method is invaluable for differentiating epileptic seizures from events of non-epileptic origin. To rule out structural central nervous system lesions and verify symptomatic forms of epilepsy, neuroimaging via brain CT or MRI is necessary.

Status Epilepticus

Status epilepticus is a critical neurological emergency defined as either a continuous epileptic seizure lasting longer than 30 minutes, or a series of recurrent seizures during which the patient does not fully regain consciousness between episodes. This condition must be distinguished from frequent individual seizures or a cluster of seizures. There are several forms of status epilepticus, including convulsive status epilepticus, absence status, and complex partial status epilepticus. Status epilepticus develops in approximately 15% of patients suffering from epilepsy.

Status epilepticus may occur in the context of symptomatic epilepsy (e.g., following a stroke or acute traumatic brain injury) or serve as a manifestation of acute decompensation of the underlying epileptic disorder. Its onset can be triggered by the abrupt withdrawal of antiepileptic drugs, intoxication, central nervous system metabolic disturbances, or acute infections; however, in many cases, the precise etiology remains unknown. The development of status epilepticus is accompanied by profound and rapidly progressive impairment of all vital Organ Systems. Disturbances in Energy Metabolism, Circulation, acid-base equilibrium, and fluid-electrolyte balance ensue. This creates a vicious cycle that exacerbates cerebral edema and leads to critical central nervous system dysfunction. Without prompt and aggressive intensive care, the prognosis for status epilepticus is generally poor. The mortality rate associated with status epilepticus can reach 18% or higher.

Conservative Treatment

The primary goal of therapy is the cessation of epileptic seizures and the reintegration of the patient into a normal, active lifestyle. The fundamental principles of epilepsy management include selecting medication appropriate to the seizure type and epilepsy syndrome, and utilizing monotherapy whenever possible. Treatment should be initiated with low doses of antiepileptic drugs, which are then gradually increased if seizures persist and no side effects occur. The following medications have long been established in the treatment of epilepsy: carbamazepine, valproates (depakote), phenytoin (diphenylhydantoin), phenobarbital, benzonal, ethosuximide, and benzodiazepines (clonazepam, as well as injectable formulations such as diazepam and lorazepam). In recent years, the pharmacological armamentarium has expanded with newer antiepileptic agents such as lamotrigine, levetiracetam, oxcarbazepine, topiramate, and gabapentin. For partial seizures, the following medications are recommended:

Valproic acid 1000–2500 mg/day

Carbamazepine    600–1200 mg/day

Topiramate    200–600 mg/day

Lamotrigine    100–200 mg/day

Oxcarbazepine    900–2400 mg/day

The addition of levetiracetam (1000–3000 mg/day) or pregabalin is also an option.

The drugs of choice for generalized seizures are valproic acid and lamotrigine. Valproic acid is recommended for unclassified seizures. For absence seizures, succinimides (ethosuximide) are prescribed, while carbamazepine and phenytoin are strictly contraindicated.

Therapeutic drug monitoring of antiepileptic Blood concentrations can significantly optimize therapy, ensuring that the maximum therapeutic effect is achieved with minimal toxicity. Monotherapy is effective in approximately 60–65% of epilepsy patients. The withdrawal of antiepileptic medications may be considered 3 years after the complete cessation of seizures. Drug dosages must be tapered gradually.

First aid for a single epileptic seizure generally consists of protecting the patient from potential traumatic injuries to the head, torso, and limbs during falls and convulsions. In some cases, once convulsions have ceased and before consciousness returns, it may be necessary to reposition the patient's head. This prevents saliva or blood (resulting from tongue biting) from entering the respiratory tract or obstructing the airway due to foreign bodies. It is vital to ensure that consciousness and adequate breathing are restored post-ictally, and that no severe Cardiac Arrhythmias are present. Trying to prevent tongue biting at the onset of a seizure is typically extremely difficult. Occasionally, this can be achieved using specialized devices when an epileptic seizure is anticipated, such as in a medical facility. However, in an accidental Setting, attempting to do so is more likely to cause dental trauma, soft tissue injury to the Oral Cavity, or aspiration of foreign objects. Fabrics, as well as metal, fragile, or crumbling objects, must never be used for this purpose. Naturally, administering antiepileptic drugs during an ongoing or already terminated single seizure serves no therapeutic purpose.

Status epilepticus requires immediate intensive care within an intensive care unit (ICU). Foreign objects must be removed from the oral cavity, an airway established, and continuous monitoring of all vital physiological parameters initiated. Respiratory and cardiovascular dysfunctions must be aggressively managed and corrected. Simultaneously, diagnostic workups are performed to rule out symptomatic forms of epilepsy secondary to acute neurological insults (traumatic brain injury, brain tumors, intoxications, meningoencephalitis). To terminate the seizures, intravenous administration of diazepam (2 ml / 10 mg) in a glucose solution is utilized. If convulsions persist, diazepam is repeated in bolus doses at 10–15 minute intervals or administered via slow intravenous drip (100 mg in 500 ml of 5% glucose solution at a rate of 40 ml/h). Repeated administration of diazepam—or similar agents—carries the risk of respiratory and hemodynamic depression. In international clinical practice, another benzodiazepine derivative, lorazepam (1 ml = 4 mg per ampoule), is more widely used and is administered as a single-ampoule intravenous bolus. Unlike diazepam, it has a longer duration of action (approximately 12 hours). If diazepam proves ineffective, alternative agents such as phenytoin, hexenal, sodium thiopental, or sodium oxybate are employed. If seizures continue, inhalational anesthesia with nitrous oxide mixed with oxygen may be used. Aggressive correction of acidosis (using sodium bicarbonate), fluid and electrolyte imbalances, hypoglycemia, disseminated intravascular coagulation (DIC), and escalating cerebral edema is mandatory.

Patients with epilepsy and their families must be educated that sleep deprivation and excessive alcohol consumption can trigger or increase the frequency of seizures. Individuals with epilepsy face certain occupational restrictions: they should avoid working at heights, driving vehicles, or operating moving machinery, open flames, or hazardous electrical equipment. Such individuals are advised against swimming alone or engaging in sports where a sudden loss of consciousness could lead to catastrophic consequences (e.g., downhill skiing, Water sports, etc.). In virtually all countries, driving is prohibited for patients with epilepsy (even with excellent seizure control—typically for at least 1 to 2 years following the last seizure). Patients with frequent seizures are advised to carry a medical alert bracelet or identification card containing their personal details, diagnosis, and basic first-aid instructions.

Surgical treatment of Epilepsy

Surgical intervention for certain symptomatic forms of epilepsy (such as tumors, abscesses, or traumatic intracranial hematomas) is necessary not only to achieve seizure freedom, but primarily to save the patient's life.

For patients with other forms of epilepsy, surgical candidacy is established only in cases of frequent, medically refractory seizures, provided that the epileptic focus within the brain structures can be precisely localized. Advanced diagnostic modalities (such as corticography or invasive intracranial electrode placement) are sometimes utilized to pinpoint the epileptogenic zone. The surgical Procedure in these cases involves the resection of the cortical tissue within the identified epileptic focus. Stereotactic techniques may also be employed.

A prominent specific instance of partial epilepsy treated surgically is temporal lobe epilepsy. In this condition, the epileptic focus develops As a result of perinatal central nervous system injuries, subsequently leading to gliosis within the hippocampus and medial temporal structures. Surgical resection of the epileptogenic cortical tissue in such cases achieves favorable outcomes in over 70% of patients. Internationally, Vagus nerve stimulation (VNS) is occasionally utilized in patients with pharmacoresistant epilepsy.

Clinical Problems

Option 1

A 20-year-old male is referred to the neurology department for evaluation of recurrent seizures occurring 1–2 times per quarter, typically starting with nausea and epigastric discomfort, dizziness, weakness, and a ringing in the head. This is followed by impaired consciousness, tonic and then clonic seizures throughout the entire body accompanied by frothing at the mouth, Urinary Incontinence, and amnesia. The seizures began about a year ago without an apparent cause. In early childhood, he experienced two episodes of febrile seizures triggered by high temperatures associated with colds. At ages 7–10, during school hours, he had several brief (lasting a few seconds) "freezing" episodes characterized by speech arrest, relaxation of facial muscles, and memory lapses. During the same period, nocturnal enuresis was occasionally noted, accompanied by a heavy head upon waking in the morning and evidence of tongue biting. Upon examination, he is fully oriented, with no focal neurological deficits. He has not been previously evaluated or treated for these seizures.

   • How can the patient's observed conditions be classified?

   • Name the indirect signs that indicate the epileptic nature of the experienced seizure.

   • What is an aura?

   • What types of aura are you familiar with?

   • Formulate a topical diagnosis.

   • Formulate a preliminary clinical diagnosis.

   • Propose the main directions for Differential diagnosis.

   • Describe the protocol for instrumental neurological examination.

   • What somatic evaluations are necessary?

   • Describe the possible EEG findings in this patient.

   • List the MAIN TYPES OF epileptic seizures.

   • State the diagnostic criteria for febrile seizures.

   • What paroxysmal conditions must be differentiated from non-convulsive epileptic seizures?

   • What circumstances may provoke seizure development in this patient?

   • Describe The Scope of emergency care for a single epileptic seizure.

   • Propose anti-seizure therapy.

   • Outline the plan for the further management of this patient.

   • What complications may arise as the disease progresses?

   • What are the specific considerations for disability assessment in this condition?

   • Formulate preventive recommendations for the patient.

Option 2

A 21-year-old young man is referred for evaluation. Family history is unremarkable. At age 12, he suffered a severe traumatic brain injury. Since then, he has been troubled by chronic headaches, which most frequently occur by the end of the day, following fatigue, and with changes in weather. At age 15, during the day while feeling generally well, colored circles appeared before his eyes, followed by a forced rightward head turn. According to relatives, he lost consciousness and fell, and clonic seizures were observed in the right side of his face and right extremities. The seizure was followed by sleep, and tongue-biting marks were later discovered. Similar seizures recurred every 2–3 months. A year after the onset of the disease, less frequent seizures appeared, characterized by sudden loss of consciousness and generalized convulsions. Recently, he has experienced several episodes involving nausea and bright circles before his eyes, accompanied by vomiting, chills, and chewing and swallowing movements. During these moments, he reportedly did not lose consciousness; however, he was unable to speak, had difficulty comprehending, and retained only partial memory of the events. Examination reveals hyperactive tendon Reflexes on the right side.

   • List the primary neurological disorders.

   • What types of seizures were observed in this patient?

   • How can the remote medical history be interpreted?

   • Explain The Significance of focal neurological symptoms.

   • Formulate the topographic diagnosis.

   • Formulate a preliminary clinical diagnosis.

   • Indicate the Morphology/3.html">MAIN DIRECTIONS OF the differential diagnosis.

   • Outline the plan for neurological and somatic examination.

   • Describe possible EEG changes in this patient.

   • Describe the scope of emergency care in the event of a single epileptic seizure.

   • Select the appropriate antiepileptic therapy.

   • Under what conditions and in what manner can antiepileptic drugs be discontinued?

   • What are the risks associated with recurrent seizures?

   • Name the factors contributing to the development and recurrence of seizures.

   • Specify the features of Work Capacity Assessment for this condition.

   • Formulate preventive recommendations for the patient.

   • Determine the prognosis of the disease.

Case 3

A 42-year-old man was admitted to the emergency department from home, where over the past few hours he had experienced three episodes characterized by loss of consciousness, generalized body convulsions, and foaming at the mouth. Details of the immediate medical history are not precisely known. According to neighbors, he suffered from a cold a few days ago, abuses alcohol, and had a single convulsive seizure about a year ago. Upon examination, he is lethargic and drowsy. His eyes are open, but he does not answer questions. Pupils are equal in size, react appropriately to light, and he fixes his gaze on surrounding objects. He turns his head toward loud speech. His face is symmetrical; the tongue is in the midline with evidence of biting marks on both sides; swallowing is intact. He responds with slow limb movements to painful stimuli and resists the examination. Tendon reflexes are brisk and symmetrical bilaterally. Inconstant Babinski signs are present. Kernig's sign and nuchal rigidity are weakly positive. The skin is somewhat pale, with several fresh abrasions on the parietal and frontal regions. Blood pressure is 160/90 mmHg, pulse is 100 and regular. Respiration rate is approximately 20 breaths per minute. At the time of examination, a generalized convulsive seizure developed.

   • How would you characterize the patient's condition upon examination?

   • Indicate the criteria for assessing his condition.

   • List the main neurological disorders.

   • Determine the level of consciousness.

   • Formulate a preliminary clinical diagnosis.

   • List the diseases that, considering the medical history and examination findings, could account for the described abnormalities.

   • What additional anamnestic details should be clarified?

   • Outline the plan and objectives of the instrumental neurological examination.

   • Describe the scope of the required somatic evaluation.

   • Outline the patient management plan.

   • Propose an antiepileptic pharmacotherapy regimen.

   • Describe Other components of comprehensive intensive care.

   • List potential complications of this condition.

   • Which patient parameters require continuous monitoring?

   • Name the diagnostic criteria for status epilepticus.

   • Determine the prognosis of the disease.