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An electroencephalogram (EEG) can assist in showing brain activity suggestive of an increased risk of seizures. It is only recommended for those who are likely to have had an epileptic seizure on the basis of symptoms. In the diagnosis of epilepsy, electroencephalography may help distinguish the type of seizure or syndrome present. In children it is typically only needed after a second seizure. It cannot be used to rule out the diagnosis and may be falsely positive in those without the disease. In certain situations it may be useful to perform the EEG while the affected individual is sleeping or sleep deprived.
Diagnostic imaging by CT scan and MRI is recommended after a first non-febrile seizure to detect structural problems in and around the brain. MRI is generally a better imaging test except when bleeding is suspected, for which CT is more sensitive and more easily available. If someone attends the emergency room with a seizure but returns to normal quickly, imaging tests may be done at a later point. If a person has a previous diagnosis of epilepsy with previous imaging, repeating the imaging is usually not needed even if there are subsequent seizures.
For adults, the testing of electrolyte, blood glucose and calcium levels is important to rule out problems with these as causes. An electrocardiogram can rule out problems with the rhythm of the heart. A lumbar puncture may be useful to diagnose a central nervous system infection but is not routinely needed. In children additional tests may be required such as urine biochemistry and blood testing looking for metabolic disorders.
A high blood prolactin level within the first 20 minutes following a seizure may be useful to help confirm an epileptic seizure as opposed to psychogenic non-epileptic seizure. Serum prolactin level is less useful for detecting focal seizures. If it is normal an epileptic seizure is still possible and a serum prolactin does not separate epileptic seizures from syncope. It is not recommended as a routine part of the diagnosis of epilepsy.
An electroencephalography is only recommended in those who likely had an epileptic seizure and may help determine the type of seizure or syndrome present. In children it is typically only needed after a second seizure. It cannot be used to rule out the diagnosis and may be falsely positive in those without the disease. In certain situations it may be useful to prefer the EEG while sleeping or sleep deprived.
Diagnostic imaging by CT scan and MRI is recommended after a first non-febrile seizure to detect structural problems inside the brain. MRI is generally a better imaging test except when intracranial bleeding is suspected. Imaging may be done at a later point in time in those who return to their normal selves while in the emergency room. If a person has a previous diagnosis of epilepsy with previous imaging repeat imaging is not usually needed with subsequent seizures.
In adults, testing electrolytes, blood glucose and calcium levels is important to rule these out as causes, as is an electrocardiogram. A lumbar puncture may be useful to diagnose a central nervous system infection but is not routinely needed. Routine antiseizure medical levels in the blood are not required in adults or children. In children additional tests may be required.
A high blood prolactin level within the first 20 minutes following a seizure may be useful to confirm an epileptic seizure as opposed to psychogenic non-epileptic seizure. Serum prolactin level is less useful for detecting partial seizures. If it is normal an epileptic seizure is still possible and a serum prolactin does not separate epileptic seizures from syncope. It is not recommended as a routine part of diagnosis epilepsy.
Diagnosis of epilepsy can be difficult. A number of other conditions may present very similar signs and symptoms to seizures, including syncope, hyperventilation, migraines, narcolepsy, panic attacks and psychogenic non-epileptic seizures (PNES). In particular a syncope can be accompanied by a short episode of convulsions. Nocturnal frontal lobe epilepsy, often misdiagnosed as nightmares, was considered to be a parasomnia but later identified to be an epilepsy syndrome. Attacks of the movement disorder paroxysmal dyskinesia may be taken for epileptic seizures. The cause of a drop attack can be, among many others, an atonic seizure.
Children may have behaviors that are easily mistaken for epileptic seizures but are not. These include breath-holding spells, bed wetting, night terrors, tics and shudder attacks. Gastroesophageal reflux may cause arching of the back and twisting of the head to the side in infants, which may be mistaken for tonic-clonic seizures.
Misdiagnosis is frequent (occurring in about 5 to 30% of cases). Different studies showed that in many cases seizure-like attacks in apparent treatment-resistant epilepsy have a cardiovascular cause. Approximately 20% of the people seen at epilepsy clinics have PNES and of those who have PNES about 10% also have epilepsy; separating the two based on the seizure episode alone without further testing is often difficult.
Differentiating an epileptic seizure from other conditions such as syncope can be difficult. Other possible conditions that can mimic a seizure include: decerebrate posturing, psychogenic seizures, tetanus, dystonia, migraine headaches, and strychnine poisoning. In addition, 5% of people with a positive tilt table test may have seizure-like activity that seems to be due to cerebral hypoxia. Convulsions may occur due to psychological reasons and this is known as a psychogenic non-epileptic seizure. Non-epileptic seizures may also occur due to a number of other reasons.
The most important factor in diagnosing a patient with vertiginous epilepsy is the subject’s detailed description of the episode. However, due to the associated symptoms of the syndrome a subject may have difficulty remembering the specifics of the experience. This makes it difficult for a physician to confirm the diagnosis with absolute certainty. A questionnaire may be used to help patients, especially children, describe their symptoms. Clinicians may also consult family members for assistance in diagnosis, relying on their observations to help understand the episodes. In addition to the description of the event, neurological, physical and hematologic examinations are completed to assist in diagnosis. For proper diagnosis, an otological exam (examination of the ear) should also be completed to rule out disorders of the inner ear, which could also be responsible for manifestations of vertigo. This may include an audiological assessment and vestibular function test. During diagnosis, history-taking is essential in determining possible causes of vertiginous epilepsy as well as tracking the progress of the disorder over time.
Other means used in diagnosis of vertiginous epilepsy include:
- Electroencephalography (EEG)
- Magnetic resonance imaging (MRI)
- Positron emission tomography (PET)
- Neuropsychological testing
The EEG measures electrical activity in the brain, allowing a physician to identify any unusual patterns. While EEGs are good for identifying abnormal brain activity is it not helpful in localizing where the seizure originates because they spread so quickly across the brain. MRIs are used to look for masses or lesions in the temporal lobe of the brain, indicating possible tumors or cancer as the cause of the seizures. When using a PET scan, a physician is looking to detect abnormal blood flow and glucose metabolism in the brain, which is visible between seizures, to indicate the region of origin.
Medical personnel aim to determine whether a seizure is caused by a change in the patient's biochemistry, such as hyponatremia. Neurological examinations and tests to measure levels of serum electrolytes are performed.
Not all seizures that occur after trauma are PTS; they may be due to a seizure disorder that already existed, which may even have caused the trauma. In addition, post-traumatic seizures are not to be confused with concussive convulsions, which may immediately follow a concussion but which are not actually seizures and are not a predictive factor for epilepsy.
Neuroimaging is used to guide treatment. Often, MRI is performed in any patient with PTS, but the less sensitive but more easily accessed CT scan may also be used.
Seizures that result from TBI are often difficult to treat. Antiepileptic drugs that may be given intravenously shortly after injury include phenytoin, sodium valproate, carbamazepine, and phenobarbital. Antiepileptic drugs do not prevent all seizures in all people, but phenytoin and sodium valproate usually stop seizures that are in progress.
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.
Many antiepileptic drugs are used for the management of canine epilepsy. Oral phenobarbital, in particular, and imepitoin are considered to be the most effective antiepileptic drugs and usually used as ‘first line’ treatment. Other anti-epileptics such as zonisamide, primidone, gabapentin, pregabalin, sodium valproate, felbamate and topiramate may also be effective and used in various combinations. A crucial part of the treatment of pets with epilepsy is owner education to ensure compliance and successful management.
The test is particularly indicated in children who have had cluster seizures in series. It is also recommended for patients who are diagnosed GEFS+ and when the seizures are associated with fever, infection, experienced regression, delayed cognitive growth or behavioral problems. The test is typically ordered by neurologists. The diagnostic test can be done by drawing blood or saliva of the patient and their immediate family. It is analyzed in laboratories that specialize in genetic testing. Genetic testing can aid in a firmer diagnosis and understanding of the disorder, may aid in identifying the optimal treatment plan and if positive, testing of the parents can determine if they are carriers. (See Genetic Counseling)
It is not known whether PTS increase the likelihood of developing PTE. Early PTS, while not necessarily epileptic in nature, are associated with a higher risk of PTE. However, PTS do not indicate that development of epilepsy is certain to occur, and it is difficult to isolate PTS from severity of injury as a factor in PTE development. About 3% of patients with no early seizures develop late PTE; this number is 25% in those who do have early PTS, and the distinction is greater if other risk factors for developing PTE are excluded. Seizures that occur immediately after an insult are commonly believed not to confer an increased risk of recurring seizures, but evidence from at least one study has suggested that both immediate and early seizures may be risk factors for late seizures. Early seizures may be less of a predictor for PTE in children; while as many as a third of adults with early seizures develop PTE, the portion of children with early PTS who have late seizures is less than one fifth in children and may be as low as one tenth. The incidence of late seizures is about half that in adults with comparable injuries.
There are three types of epilepsy in dogs: reactive, secondary, and primary. Reactive epileptic seizures are caused by metabolic issues, such as low blood sugar or kidney or liver failure. Epilepsy attributed to brain tumor, stroke or other trauma is known as secondary or symptomatic epilepsy.
There is no known cause for primary or idiopathic epilepsy, which is only diagnosed by eliminating other possible causes for the seizures. Dogs with idiopathic epilepsy experience their first seizure between the ages of one and three. However, the age at diagnosis is only one factor in diagnosing canine epilepsy, as one study found cause for seizures in one-third of dogs between the ages of one and three, indicating secondary or reactive rather than primary epilepsy.
A veterinarian's initial work-up for a dog presenting with a history of seizures may include a physical and neurological exam, a complete blood count, serum chemistry profile, urinalysis, bile tests, and thyroid function tests. These tests verify seizures and may determine cause for reactive or secondary epilepsy. Veterinarians may also request that dog owners keep a "seizure log" documenting the timing, length, severity, and recovery of each seizure, as well as dietary or environmental changes.
Diagnosis can be made by EEG. In case of epileptic spasms, EEG shows typical patterns.
PCDH19 gene-related epilepsy is clinically based on patient and family seizure history, cognitive and behavioral neuropsychological evaluation, neurological examination, electroencephalogram (EEG) studies, and long term observation. Diagnosis is confirmed using molecular testing for PCDH19 mutations.
Because epileptic seizures may occur with a side effect that resembles migraine aura, it is complicated to diagnose whether a patient is having a normal epileptic episode or if it is a true migraine that is then being followed by a seizure, which would be a true sign of migralepsy. Many neurological symptoms can only be expressed by the patient, who can confuse different feelings, especially when the symptoms of a migraine are extremely similar to that of a seizure. Thus, many physicians are reluctant to consider migralepsy to be a true condition, considering its rarity, and those that do believe in it are prone to over-diagnose it, leading to more problems in terms of finding the truth of the condition.
However, it has been found that EEG scans have been able to differentiate between migraine auras and auras related to epilepsy. It has generally been seen that EEG scans are not as helpful in determining facets of migraines as they are with epilepsy. Though they are able to work in determining the starting and ending points of migraines and the overlap of epileptic episodes during or after them, even if the scans are still lacking in considerable necessary data and confusing results. EEG scans have been able to observe seizures that occur in between the aura and headache phase of migraines and such occurrences have been termed intercalated seizures.
The presence of porencephalic cysts or cavities can be detected using trans-illumination of the skull of infant patients. Porencephaly is usually diagnosed clinically using the patients and families history, clinical observations, or based on the presence of certain characteristic neurological and physiological features of porencephaly. Advanced medical imaging with computed tomography (CT), magnetic resonance imaging (MRI), or with ultrasonography can be used as a method to exclude other possible neurological disorders. The diagnosis can be made antenatally with ultrasound. Other assessments include memory, speech, or intellect testing to help further determine the exact diagnose of the disorder.
Several specific diagnostic criteria can be used to diagnose vascular dementia, including the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition (DSM-IV) criteria, the International Classification of Diseases, Tenth Edition (ICD-10) criteria, the National Institute of Neurological Disorders and Stroke criteria, Association Internationale pour la Recherche et l'Enseignement en Neurosciences (NINDS-AIREN) criteria, the Alzheimer's Disease Diagnostic and Treatment Center criteria, and the Hachinski Ischemic Score (after Vladimir Hachinski).
The recommended investigations for cognitive impairment include: blood tests (for anemia, vitamin deficiency, thyrotoxicosis, infection, etc.), chest X-Ray, ECG, and neuroimaging, preferably a scan with a functional or metabolic sensitivity beyond a simple CT or MRI. When available as a diagnostic tool, single photon emission computed tomography (SPECT) and positron emission tomography (PET) neuroimaging may be used to confirm a diagnosis of multi-infarct dementia in conjunction with evaluations involving mental status examination. In a person already having dementia, SPECT appears to be superior in differentiating multi-infarct dementia from Alzheimer's disease, compared to the usual mental testing and medical history analysis. Advances have led to the proposal of new diagnostic criteria.
The screening blood tests typically include full blood count, liver function tests, thyroid function tests, lipid profile, erythrocyte sedimentation rate, C reactive protein, syphilis serology, calcium serum level, fasting glucose, urea, electrolytes, vitamin B-12, and folate. In selected patients, HIV serology and certain autoantibody testing may be done.
Mixed dementia is diagnosed when people have evidence of Alzheimer's disease and cerebrovascular disease, either clinically or based on neuro-imaging evidence of ischemic lesions.
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.
Since migralepsy is, for all intents and purposes, a combination of migraines and epilepsy, the medication for the conditions supplied individually can be combined jointly in order to lessen the effects of both. It is also helpful that many antiepileptic drugs also work as antimigraines, lessening the number of medications that must be taken. Thus, while neither can be cured, they can be treated so that they occur less frequently and allow a patient to live a relatively normal life.
Gross examination of the brain may reveal noticeable lesions and damage to blood vessels. Accumulation of various substances such as lipid deposits and clotted blood appear on microscopic views. The white matter is most affected, with noticeable atrophy (tissue loss), in addition to calcification of the arteries. Microinfarcts may also be present in the gray matter (cerebral cortex), sometimes in large numbers.
Although atheroma of the major cerebral arteries is typical in vascular dementia, smaller vessels and arterioles are mainly affected.
The diagnosis may be made on the clinical features alone, along with tests to rule out other possible causes. An EEG will usually show the electrical features of epilepsy and slowing of brain activity in the affected hemisphere, and MRI brain scans will show gradual shrinkage of the affected hemisphere with signs of inflammation or scarring.
Brain biopsy can provide very strong confirmation of the diagnosis, but this is not always necessary.
It is not possible to make a generalised prognosis for development due to the variability of causes, as mentioned above, the differing types of symptoms and cause. Each case must be considered individually.
The prognosis for children with idiopathic West syndrome are mostly more positive than for those with the cryptogenic or symptomatic forms. Idiopathic cases are less likely to show signs of developmental problems before the attacks begin, the attacks can often be treated more easily and effectively and there is a lower relapse rate. Children with this form of the syndrome are less likely to go on to develop other forms of epilepsy; around two in every five children develop at the same rate as healthy children.
In other cases, however, treatment of West syndrome is relatively difficult and the results of therapy often dissatisfying; for children with symptomatic and cryptogenic West syndrome, the prognosis is generally not positive, especially when they prove resistant to therapy.
Statistically, 5 out of every 100 children with West syndrome do not survive beyond five years of age, in some cases due to the cause of the syndrome, in others for reasons related to their medication. Only less than half of all children can become entirely free from attacks with the help of medication. Statistics show that treatment produces a satisfactory result in around three out of ten cases, with only one in every 25 children's cognitive and motoric development developing more or less normally.
A large proportion (up to 90%) of children suffer severe physical and cognitive impairments, even when treatment for the attacks is successful. This is not usually because of the epileptic fits, but rather because of the causes behind them (cerebral anomalies or their location or degree of severity). Severe, frequent attacks can (further) damage the brain.
Permanent damage often associated with West syndrome in the literature include cognitive disabilities, learning difficulties and behavioural problems, cerebral palsy (up to 5 out of 10 children), psychological disorders and often autism (in around 3 out of 10 children). Once more, the cause of each individual case of West syndrome must be considered when debating cause and effect.
As many as 6 out of 10 children with West syndrome suffer from epilepsy later in life. Sometimes West syndrome turns into a focal or other generalised epilepsy. Around half of all children develop Lennox-Gastaut syndrome.
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.
Socioeconomic correlates of health have been well established in the study of heart disease, lung cancer, and diabetes. Many of the explanations for the increased incidence of these conditions in people with lower socioeconomic status (SES) suggest they are the result of poor diet, low levels of exercise, dangerous jobs (exposure to toxins etc.) and increased levels of smoking and alcohol intake in socially deprived populations. Hesdorffer et al. found that low SES, indexed by poor education and lack of home ownership, was a risk factor for epilepsy in adults, but not in children in a population study. Low socioeconomic status may have a cumulative effect for the risk of developing epilepsy over a lifetime.
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.