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Many anticonvulsant oral medications are available for the management of temporal lobe seizures. Most anticonvulsants function by decreasing the excitation of neurons, for example, by blocking fast or slow sodium channels or by modulating calcium channels; or by enhancing the inhibition of neurons, for example by potentiating the effects of inhibitory neurotransmitters like GABA.
In TLE, the most commonly used older medications are phenytoin, carbamazepine, primidone, valproate, and phenobarbital. Newer drugs, such as gabapentin, topiramate, levetiracetam, lamotrigine, pregabalin, tiagabine, lacosamide, and zonisamide promise similar effectiveness, with possibly fewer side-effects. Felbamate and vigabatrin are newer, but can have serious adverse effects so they are not considered as first-line treatments.
Up to one third of patients with medial temporal lobe epilepsy will not have adequate seizure control with medication alone. For patients with medial TLE whose seizures remain uncontrolled after trials of several types of anticonvulsants (that is, the epilepsy is "intractable"), surgical excision of the affected temporal lobe may be considered.
Most children who develop epilepsy are treated conventionally with anticonvulsants. In about 70% of cases of childhood epilepsy, medication can completely control seizures. Unfortunately, medications come with an extensive list of side effects that range from mild discomfort to major cognitive impairment. Usually, the adverse cognitive effects are ablated following dose reduction or cessation of the drug.
Medicating a child is not always easy. Many pills are made only to be swallowed, which can be difficult for a child. For some medications, chewable versions do exist.
The ketogenic diet is used to treat children who have not responded successfully to other treatments. This diet is low in carbohydrates, adequate in protein and high in fat. It has proven successful in two thirds of epilepsy cases.
In some cases, severe epilepsy is treated with the hemispherectomy, a drastic surgical procedure in which part or all of one of the hemispheres of the brain is removed.
Over the past decade or so, researchers have been attempting to discover less invasive, safer and more efficient technologies that enable surgeons to remove epileptogenic focal zones without causing any damage to neighboring cortical areas. One such technology that has emerged and has great promise, is the use of gamma knife radiosurgery to either excise a brain tumor or repair a vascular malformation.
In Gamma Knife radiosurgery, intersecting gamma radiation beams are applied directly to the tumor site or vascular malformation site that had been established using neuroimaging. Although each beam itself is not strong enough to damage brain tissue, when the beams interesect they are strong enough to destroy the specific brain tissue that is to be excised. This process is extremely efficient and entirely non-invasive and is therefore much safer than actual neurosurgery itself.
Recently researchers and surgeons alike have begun to use Gamma Knife radiosurgery to treat cases of epilepsy by removing tumors responsible for causing the seizures. The early success rates in being able to alleviate seizures seem to be similar to those of temporal resective surgery however Gamma Knife radiosurgery has less associated risk factors. Current research on this topic is aimed at improving the technique in order to increase success rates as well as developing non-invasive forms of physiologic monitoring in order to determine the epileptogenic focus conclusively.
There are several different ways to treat frontal lobe epileptic seizures, however, the most common form of treatment is through the use of anticonvulsant medications that help to prevent seizures from occurring. In some cases, however, when medications are ineffective, a neurologist may choose to operate on the patient in order to remove the focal area of the brain in which the seizures are occurring. Other treatments that can be administered to aid in reducing the occurrence of seizures include the implementation of a specific, regimented diet and/or the implantation of a vagus nerve stimulator.
In 1999, Sachdeo and colleagues at the University of Medicine and Dentistry of New Jersey and the Robert Wood Johnson Medical School in New Brunswick reported that 33% of the patients in a group of patients taking topiramate experienced a minimum 50% reduction in seizures (specifically drop attacks and tonic–clonics), compared with 8% in the placebo group. It was also found to be effective as an adjunctive therapy in a review published by Drs. Edith Alva Moncayo and Antonio Ruiz Ruiz in March 2003.
Motte reported in 1997 that lamotrigine was effective in the treatment of LGS, with the most common side effect in the treatment group relative to placebo being colds or viral illnesses. Two years later, it was approved by Health Canada for adjunctive therapy in Lennox Gastaut in adults and children. The United States Food and Drug Administration approved it for that in August 1998.
Felbamate is indicated in the use of LGS in the event that everything else fails, and was found to be superior to placebo in controlling treatment resistant partial seizures and atonic seizures. However, it has been known to cause aplastic anemia and liver toxicity.
Epilepsy surgery has been performed since the 1860s and doctors have observed that it is highly effective in producing freedom from seizures. However, it was not until 2001 that a scientifically sound study was carried out to examine the effectiveness of temporal lobectomy.
Temporal lobe surgery can be complicated by decreased cognitive function. However, after temporal lobectomy, memory function is supported by the opposite temporal lobe; and recruitment of the frontal lobe. Cognitive rehabilitation may also help.
Though there is limited evidence, outcomes appear to be relatively poor with a review of outcome studies finding that two thirds of PNES patients continue to experience episodes and more than half are dependent on social security at three-year followup. This outcome data was obtained in a referral-based academic epilepsy center and loss to follow-up was considerable; the authors point out ways in which this may have biased their outcome data. Outcome was shown to be better in patients with higher IQ, social status, greater educational attainments, younger age of onset and diagnosis, attacks with less dramatic features, and fewer additional somatoform complaints.
The prognosis of ICOE-G is unclear, although available data indicate that remission occurs in 50–60% of patients within 2–4 years of onset. Seizures show a dramatically good response to carbamazepine in more than 90% of patients. However, 40–50% of patients may continue to have visual seizures and infrequent secondarily generalized convulsions, particularly if they have not been appropriately treated with antiepileptic drugs.
No high quality evidence has shown any drug very useful as of 2013. Rufinamide, lamotrigine, topiramate and felbamate may be useful.
Patients with ICOE-G need prophylactic treatment mainly with carbamazepine or other antiepileptic drugs licensed for focal seizures. A slow reduction in the dose of medication 2 or 3 years after the last visual or other minor or major seizure should be advised, but if visual seizures reappear, treatment should be restored.
Given the benign nature of the condition and the low seizure frequency, treatment is often unnecessary. If treatment is warranted or preferred by the child and his or her family, antiepileptic drugs can usually control the seizures easily. Carbamazepine is the most frequently used first-line drug, but many other antiepileptic drugs, including valproate, phenytoin, gabapentin, levetiracetam and sultiame have been found effective as well. Bedtime dosing is advised by some. Treatment can be short and drugs can almost certainly be discontinued after two years without seizures and with normal EEG findings, perhaps even earlier.
Parental education about Rolandic epilepsy is the cornerstone of correct management. The traumatizing, sometimes long-lasting effect on parents is significant.
It is unclear if there are any benefits to clobazam over other seizure medications.
Deep brain stimulation of the anterior nuclei of the thalamus is approved for DRE in some countries in Europe, but has been and continues to only be used in a very few patients. After 5 years of DBS a seizure reduction of 69% and a 50%-responder rate of 68% was reported in a randomized-double blinded trial. The rate of serious device related events was 34% in this study.
Responsive neurostimulation (RNS) is approved for DRE in the USA and involves stimulation directly to 1 or 2 seizure foci when abnormal electrocorticographic activity is detected by the devices software. After 2 years of RNS a seizure reduction of 53% was reported in a randomized-double blinded trial as well as a rate of serious device related events of 2.5%.
Transcutaneous vagus nerve stimulation (tVNS) is approved for DRE in some European countries and involves externally stimulating the auricular branch of the vagus nerve in the ear. tVNS failed to demonstrate efficacy in a first randomized-double blinded trial: responder rates did not differ between active and control groups potentially indicating a placebo effect behind the 34% seizure reduction seen in the patients who completed the full follow-up period.
A modified Atkins diet describes the long term practice of the first phase of the popular Atkins diet the so-called induction phase to reduce seizures through ketosis. In this diet the fat content of the nutrition is slightly lower than in the ketogenic diet at around 60%, the protein content is around 30% and the carbohydrate content is around 10% rendering the diet less restrictive and more compatible with the daily life compared to the ketogenic diet. Several studies show that the modified Atkins diet produces a similar or slightly lower seizure reduction to the ketogenic diet. Some physicians, especially in the USA, recommend the modified Atkins diet because they assume that patients will adhere to it on the long-term because it is more compatible with daily life and the meals are more enjoyable. It has also been concluded in another study that the diet is well tolerated and effective in hard to treat childhood epilepsy.
Like many other types of seizures, gelastic seizures are hard to control for an extended period of time. The best outlook is for children suffering the seizures due to a benign tumor in their hypothalamus. The removal of these tumors can be effective not only for the frequency of the seizures, but also the behavioral and cognitive symptoms that come along with the syndrome. Cases have also been described where that antiepileptic drugs have stopped seizures fully.
The causes of epilepsy in childhood vary. In about ⅔ of cases, it is unknown.
- Unknown 67.6%
- Congenital 20%
- Trauma 4.7%
- Infection 4%
- Stroke 1.5%
- Tumor 1.5%
- Degenerative .7%
Gelastic seizures are usually not responsive to pharmacotherapy. They can produce secondary seizure characteristics which may respond to medications or surgery. These options are not a guaranteed cure, and depend primarily on the individual patient’s pathology.
The treatment depends on the cause of the seizures. If the seizures are caused by a tumor, surgical removal can be attempted. However, surgical removal is not always an immediate cure, and there can be complications. Complications can include cerebral infarcts, and cognitive deterioration. Hormonal treatment can be attempted to help individuals with precocious puberty. Anti-epileptic drugs could be an option as well depending on the patient’s criteria. These drugs could include carbamazepine, clobazam, lamotrigine, levetiracetam, oxcarbazepine and topiramate. However, usually none of these medications are capable of stopping the seizures from occurring, and like any medication, there may be undesirable side effects. There is also a specialized form of radiotherapy that may be an option depending on the tumor type and location. Once again, there are very few areas in the world that offer this treatment. Gamma knife radiosurgery can be the treatment of choice when it comes to hypothalamic hamartomas. It is a low risk option due to its lower frequency of neurological deficits. It is recommended for patients with tumors that don’t come into contact with the optic chiasm.
Unfortunately, there is no real way to prevent against vertiginous episodes out of the means of managing the disease. As head trauma is a major cause for vertiginous epilepsy, protecting the head from injury is an easy way to avoid possible onset of these seizures. With recent advances in science it is also possible for an individual to receive genetic screening, but this only tells if the subject is predisposed to developing the condition and will not aid in preventing the disease.
There is a range of ways to manage vertiginous epilepsy depending on the severity of the seizures. For simple partial seizures medical treatment is not always necessary. To the comfort of the patient, someone ailed with this disease may be able to lead a relatively normal life with vertiginous seizures. If, however, the seizures become too much to handle, antiepileptic medication can be administered as the first line of treatment. There are several different types of medication on the market to deter epileptic episodes but there is no support to show that one medication is more effective than another. In fact, research has shown that simple partial seizures do not usually respond well to medication, leaving the patient to self-manage their symptoms. A third option for treatment, used only in extreme cases when seizure symptoms disrupt daily life, is surgery wherein the surgeon will remove the epileptic region.
There have been early and consistent strategies for measurement to better understand vertiginous epilepsy including caloric reflex test, posture and gait, or rotational experimentation.
In Japan, Kaga et al prepared a longitudinal study of rotation tests comparing congenital deafness and children with delayed acquisition of motor system skills. They were able to demonstrate the development of post-rotation nystagmus response from the frequency of beat and duration period from birth to six years to compare to adult values. Overall, the study demonstrated that some infants from the deaf population had impaired vestibular responses related to head control and walking age. A side interpretation included the evaluation of the vestibular system in reference to matching data with age.
Research in this area of medicine is limited due to its lacking need for urgent attention. But, the American Hearing Research Foundation (AHRF) conducts studies in which they hope to make new discoveries to help advance treatment of the disease and possibly one day prevent vertiginous seizures altogether.
The prognosis for Rolandic seizures is invariably excellent, with probably less than 2% risk of developing absence seizures and less often GTCS in adult life.
Remission usually occurs within 2–4 years from onset and before the age of 16 years. The total number of seizures is low, the majority of patients having fewer than 10 seizures; 10–20% have just a single seizure. About 10–20% may have frequent seizures, but these also remit with age.
Children with Rolandic seizures may develop usually mild and reversible linguistic, cognitive and behavioural abnormalities during the active phase of the disease. These may be worse in children with onset of seizures before 8 years of age, high rate of occurrence and multifocal EEG spikes.
The development, social adaptation and occupations of adults with a previous history of Rolandic seizures were found normal.
Prevention of PTE involves preventing brain trauma in general; protective measures include bicycle helmets and child safety seats. No specific treatment exists to prevent the development of epilepsy after TBI occurs. In the past, antiepileptic drugs were used with the intent of preventing the development of PTE. However, while antiepileptic drugs can prevent early PTS, clinical studies have failed to show that prophylactic use of antiepileptic drugs prevents the development of PTE. Why antiepileptic drugs in clinical trials have failed to stop PTE from developing is not clear, but several explanations have been offered. The drugs may simply not be capable of preventing epilepsy, or the drug trials may have been set up in a way that did not allow a benefit of the drugs to be found (e.g. drugs may have been given too late or in inadequate doses). Animal studies have similarly failed to show much protective effect of the most commonly used seizure medications in PTE trials, such as phenytoin and carbamazepine. Antiepileptic drugs are recommended to prevent late seizures only for people in whom PTE has already been diagnosed, not as a preventative measure. On the basis of the aforementioned studies, no treatment is widely accepted to prevent the development of epilepsy. However, it has been proposed that a narrow window of about one hour after TBI may exist during which administration of antiepileptics could prevent epileptogenesis (the development of epilepsy).
Corticosteroids have also been investigated for the prevention of PTE, but clinical trials revealed that the drugs did not reduce late PTS and were actually linked to an increase in the number of early PTS.
At the hospital, physicians follow standard protocol for managing seizures. Cluster seizures are generally controlled by benzodiazepines such as diazepam, midazolam, lorazepam or clonazepam. The use of oxygen is recommended in the United States, but in Europe it is only recommended in cases of prolonged epileptic status.
Like other forms of epilepsy, abdominal epilepsy is treated with anticonvulsant drugs, such as phenytoin. Since no controlled studies exist, however, other drugs may be equally effective.
Musicogenic epilepsy is a form of reflex epilepsy with seizures elicited by special stimuli.
It has probably been described for the first time in 1605 by the French philosopher and scholar Joseph Justus Scaliger (1540-1609). Later publications were, in the eighteenth century, among others, by the German physician Samuel Schaarschmidt, in the nineteenth century 1823 by the British physician John C. Cooke, 1881 by the British neurologist and epileptologist William Richard Gowers, as well as in 1913 by the Russian neurologist, clinical neurophysiologist and psychiatrist Vladimir Mikhailovich Bekhterev. In 1937 the British neurologist Macdonald Critchley coined the term for the first time and classified it as a form of reflex epilepsy.
Most patients have temporal lobe epilepsy. Listening, probably also thinking or playing, of usually very specific music with an emotional content triggers focal seizures with or without loss of awareness, occasionally also evolving to bilateral tonic-clonic seizures.
Although musicality is at least in non-musicians predominantly located in the right temporal lobe, the seizure onset may also be left-hemispherical. Of the approximately 100 patients reported in the literature so far, about 75% had temporal lobe epilepsy, women were slightly more affected, and the mean age of onset was about 28 years. Ictal EEG and SPECT findings as well as functional MRI studies localized the epileptogenic area predominantly in the right temporal lobe. Treatment with epilepsy surgery leading to complete seizure freedom has been reported.
Antiepileptic drugs (AEDs) are used in most cases to control seizures, however, PCDH19 gene-related epilepsy is generally associated with early-onset development of drug resistant seizures. Existing data supports the use of “rational polypharmacy,” which consists of a step-wise addition of AEDs until a patient responds favorably or experiences intolerable adverse events. In general, as in other types of uncontrolled epilepsy, the use of drugs with different mechanisms of action appears to be more effective than combining drugs with similar mechanisms of action.
No currently marketed AEDs have been extensively studied in PCDH19 gene-related epilepsy and there is no established treatment strategy for girls diagnosed with PCDH19 gene-related epilepsy. Patients may respond well to treatment with levetiracetam and in cases of drug resistance, stiripentol, which is not approved in the U.S. but is available through the FDA Expanded Access IND process.
The lack of generally recognized clinical recommendations available are a reflection of the dearth of data on the effectiveness of any particular clinical strategy, but on the basis of present evidence, the following may be relevant:
- Epileptic seizure control with the appropriate use of medication and lifestyle counseling is the focus of prevention.
- Reduction of stress, participation in physical exercises, and night supervision might minimize the risk of SUDEP.
- Knowledge of how to perform the appropriate first-aid responses to seizure by persons who live with epileptic people may prevent death.
- People associated with arrhythmias during seizures should be submitted to extensive cardiac investigation with a view to determining the indication for on-demand cardiac pacing.
- Successful epilepsy surgery may reduce the risk of SUDEP, but this depends on the outcome in terms of seizure control.
- The use of anti suffocation pillows have been advocated by some practitioners to improve respiration while sleeping, but their effectiveness remain unproven because experimental studies are lacking.
- Providing information to individuals and relatives about SUDEP is beneficial.