Partial (focal) Epilepsy Syndromes of Infancy and Early Childhood (ages 1 to 12)
Partial seizures are the most common types of seizures and can occur at any age. They are caused by abnormal electrical discharges that originate in one hemisphere or focal area of the brain. Their signs vary considerably and relate to the specific functions that are controlled by the brain areas involved.
Partial seizures are divided into two major categories, simple and complex. Simple partial seizures occur in full consciousness; complex partial seizures occur with impaired awareness that ranges from clouded to complete unconsciousness.
Partial seizure syndromes are marked by seizures that begin as partial seizures, episodes whose symptoms are confined to one side of the body. The seizures may sometimes evolve to what are termed generalized seizures, episodes that involve both sides of the body.
The syndromes are categorized as either idiopathic, when their cause is unknown, or symptomatic, when they have a known or presumed cause. Among known causes often seen with the symptomatic syndromes are brain tumors of various types, disorders of brain development, vascular malformations in the brain and brain infections.
The symptomatic syndromes that are identified by the brain region of seizure onset account for 40 percent of epilepsy in children, and tend to be more resistant to drug therapy.
- Benign focal epilepsy of childhood / benign rolandic epilepsy syndrome
- Early-onset benign childhood occipital epilepsy / Panayiotopoulos syndrome
- Temporal lobe epilepsy syndrome
- Frontal lobe epilepsy syndrome
- Parietal lobe epilepsy syndrome
- Occipital lobe epilepsy syndrome
Partial seizures are expressed in the following manners, dependent on the brain area(s) involved:
- Motor activity (the tensing or relaxing of a muscle or group of muscles)
- Sensory phenomenon (false impressions of taste, touch, vision, hearing or smell)
- Autonomic activity (abdominal discomfort, sweating, ‘goose flesh,’ flushing or pallor, pupil dilation, incontinence)
- Psychic phenomenon (garbled or arrested speech, distortions of memory, time,
- or perceptions of reality, and feelings of anxiety, fear, elation, etc.)
Benign focal epilepsy of childhood / rolandic epilepsy syndrome (ages 2 to 12)
Rolandic epilepsy syndrome is the most common epileptic syndrome of childhood, representing 15 percent to 25 percent of childhood epilepsy. The syndrome takes its name from the gyrus of Rolando, the brain area that produces the EEG brain-wave pattern characteristic of this form of epilepsy. Although this distinctive EEG pattern is seen in 2 percent of healthy children, only 8 percent of these children will have epilepsy.
Children with rolandic epilepsy have normal development and normal neurological signs. Most do not have learning problems, although some may have specific problems with reading and language.
In one study, 50 percent of close relatives were found to have the characteristic brain-wave abnormality between ages 5 and 15 , but of all children who inherit this abnormality, only 12 percent will actually have seizures.
The first sign of rolandic epilepsy is typically a seizure during sleep. The seizure presents as a rhythmic tightening and relaxing of muscles on one side of the face and, perhaps, of the arm on the same side. The episodes awaken the child and may involve mouth movements, possible drooling and/or gurgling sounds without loss of consciousness.
Seizures during the day also include the lips, gums and cheek, the build up of saliva, speech arrest, and a tightening or twitching of face muscles on one side. Consciousness is maintained and movements of the arm and/or leg may also occur. The child may feel a numbness of the lips, gums and cheek after the episode.
Seizures in rolandic epilepsy are typically easy to control and usually disappear by age 16with or without treatment . The seizures are infrequent. Some doctors do not recommend treatment if the seizures happen only at night while others may not begin treatment until several seizures have occurred. Medications used in treating this condition are Phenobarbital, phenytoin, carbamazapine, oxcarbamazapine and valproate. Most children can be tapered off of medication after one or two years of therapy.
Early-onset childhood benign occipital epilepsy / Panayiotopoulos syndrome (17 months to 8 years)
Early-onset benign epilepsy of childhood with occipital seizures is a distinct form of occipital epilepsy—seizures that originate in the brain area responsible for vision. The peak age of onset for the early form is between ages 3 and 5. The late form (Gastaut type) has a peak onset between ages 7 and 9.
Seizures are infrequent with two-thirds of seizures occurring at night, usually shortly after the child falls asleep. The episodes typically last less than 10 minutes, with vomiting and gazing toward one side, and often evolving to rhythmic muscle contractions on one or both sides of the body. Episodes occur with or without impairment of consciousness. They are occasionally triggered or aggravated by turning off lights, going from lighted areas to dark ones, or from dark areas to light ones.
Some children may experience headache and visual symptoms—colored shapes, flashes of light—in associated with the seizure. The condition is sometimes confused with migraines, as these headaches are common either before, during or after the seizures.
The prognosis for early-onset childhood benign occipital epilepsy is excellent with most children outgrowing the condition after several years.
Children with this form of epilepsy have a genetic predisposition. The syndrome represents about 3 percent of childhood epilepsy, with a somewhat higher incidence in girls than in boys.
Occipital lobe epilepsy syndrome
The hallmarks of occipital epilepsy are visual hallucinations of stationary or moving colored shapes and flashes of light, with temporary loss of vision. The gaze is often fixed to one side. The episode may begin with forced blinking and an eyelid flutter, which are important signs in aiding diagnosis when the seizure spreads rapidly to adjacent brain areas.
About three-fourths of children with this syndrome have structural abnormalities of the occipital lobe, often due to perinatal brain injury and lack of oxygen. The condition is sometimes associated with Sturge-Weber (port wine) syndrome, celiac disease, Lafora disease and mitochondrial disorders.
Occipital lobe epilepsy syndrome is rare. Treatment for this syndrome and the prognosis for children who have it depend in each case upon the specific cause.
Mesial temporal lobe epilepsy syndrome
Temporal lobe seizures often begin with auras or conscious feelings of a rising sensation from the stomach and of fear. One of the sensory perceptions may also be triggered. Impaired awareness follows, typically with staring and movements of the lips, tongue or jaw. Fumbling, picking or gesturing may also occur. In very young children, the most prominent sign may be the stopping of all movement.
About 40 percent of children with mesial temporal epilepsy have previously had febrile seizures. Many also have a family history of epilepsy. Resistance to drug therapy is frequent, but brain surgery in these difficult- to-treat cases is 80 percent to 90 percent successful.
Nocturnal frontal lobe epilepsy syndrome
Nocturnal frontal lobe epilepsy is an inherited condition affecting children aged 2 and above.
The syndrome is characterized by:
- Seizure clusters
- Occurring only during sleep
- History of nocturnal frontal lobe epilepsy in other family members
- Normal intelligence
- Normal findings on neuroimaging
- Frenetic or agitated appearance at onset
With nocturnal frontal lobe epilepsy, seizures begin shortly after falling asleep or in the early hours before awakening with a gasp, grunt, hum , moan or word, and are followed by sudden thrashing movements . The child remains conscious but can neither control the movements nor speak. Thrashing can be vigorous enough to throw the child out of bed, which can result in possible injury.
Seizures usually last a minute or less, although the child may aimlessly wander of two to three minutes . During such wandering episodes, the child might scream and try to escape. Some children will have drop attacks or generalized tonic-clonic seizures as well.
Nocturnal frontal lobe epilepsy is typically treated with carbamazapine and, in some cases, surgery. ( The syndrome rarely goes into full remission.)
Parietal lobe epilepsy syndrome
Pariental lobe epilepsy is the least common of syndromes defined by area of brain affected. Parietal seizures spread rapidly, producing a range of symptoms that are also seen with other syndromes. A few signs are typical but appear in less than half of children who have this syndrome. Among the symptoms are:
- Tingling, pricking or crawling sensations upon the skin
- The feeling of burning, itching or pain
- Pain occurs in the extremities and sometimes in the abdomen. A confused, disoriented state may also occur.
The body parts most frequently involved are the hand, arms and face. The symptoms may proceed to adjacent parts as the seizure progresses.
Partial seizures are divided into two major categories, simple and complex. Simple partial seizures occur in full consciousness; complex partial seizures occur with impaired awareness that ranges from slight to complete unconsciousness.