Epilepsy

Epilepsy Medical Terminology HLT 143-V1 Instructor: Susan R. Owen, MSN, and M.Ed. Written by: Jamie Swann Epilepsy, also known as a seizure disorder, is a chronic neurological condition caused by brief, strong surges of electrical activity in the brain. The electrical activity can affect part or all of the brain. The result of the strong surges of electrical activity is a seizure. Seizures can last from a few seconds to several minutes and can take many different forms, from loss of consciousness, convulsions, and confusion. Seizures can also take less commonly known forms, such as blank staring, laughing, lip smacking, or any number of appearances, including combinations of the above. People affected with epilepsy can have different types of seizures, because epilepsy is not a single disorder, but more than 40 different syndromes. Epilepsy is one the most common neurological diseases, affecting up to 3% of the population by age 80.[i] The incidence of epilepsy is 23-190 per 100,000. Epilepsy rates tend to be lower in infancy in industrialized nations and increase in prevalence by age. Approximately 200,000 new cases of epilepsy will be diagnosed this year in the United States alone. Children under the age of 2 and adults 65 and older are most at risk for developing epilepsy. The incidence of epilepsy is higher in African Americans and socially disadvantages populations. Men tend to be affected more by epilepsy than women, though the difference is small. Mental retardation and cerebral palsy increase the risk of developing epilepsy. If a person suffers with both conditions, epilepsy risk increases to 50%. Due to the many syndromes and conditions that lead to epilepsy, hard risk specifics can be difficult, however, the risk of developing epilepsy is generally about 1%. In approximately 7 out of 10 cases of diagnosed epilepsy, no underlying cause can be found. Other causes include stroke, brain injury, brain tumors, infection, complications during childbirth and certain genetic disorders. Infections, tumors, and trauma to the brain can disturb the electrical balance in the brain, leading to epilepsy. For the majority of epilepsy sufferers, the underlying cause cannot be found and the epilepsy is simply described by the seizure type or epileptic syndrome. Seizures are caused by abnormal synchronization of the electrical impulses in the brain. As electrical impulses travel through the brain, neurotransmitters are released. Neurotransmitters can act in an inhibitory or excitatory fashion. If more excitatory transmitters, or not enough inhibitory transmitters are released, a seizure is likely. Uncontrolled firing of neurons in the brain is ultimately what causes a seizure. A sudden burst of firing may not cause a seizure, but if it lasts long enough, or affects enough of the brain, a seizure occurs. Seizure threshold is the concept that every person has a balance of excitatory or inhibitory transmitters that make him or her more or less likely to develop seizures. In 400 B.C. Hippocrates suggested that epilepsy had a genetic origin.[ii] In 1989 the first epileptic syndrome was mapped to a gene. According to the “Epilepsy Family Study of Columbia University”, in close relatives of people with generalized epilepsy, there is a 4 times greater incidence of epilepsy, than in the general population. Unfortunately, in most families, epilepsy does not follow any specific dominant or recessive pattern, making it more difficult to map. Only a few types of epileptic syndromes are connected with a single gene. Most epilepsies are polygenic and multifactorial. One study found a link between generalized epilepsies and childhood absence epilepsies and juvenile absence epilepsies.[iii] Febrile seizures and unclassified tonic-clonic seizures were also frequent in relatives of those with generalized epilepsy. In epilepsies caused by known factors, such as brain injury or stroke, genetics do not play a role. Due to the varying nature of epileptic syndromes, symptoms of epilepsy can differ greatly. Often, when the word seizure is mentioned, people typically think of the grand mal or tonic-clonic seizure. During a generalized tonic-clonic seizure, the person loses consciousness, followed by a stiffening of the limbs (tonic phase), which is then followed by a jerking of the limbs and face (the clonic phase). These seizures generally last for one to three minutes. Other generalized seizures include myoclonic, atonic, infantile spasms and absence seizures. Generalized seizures involve both sides of the brain, and typically tend to have more hereditary involvement. Myoclonic seizures involve jerking of both sides of the body. These jerks are usually very quick and abrupt, similar to the jerking that many of us experience as we are falling asleep. Within the myoclonic category, there are several distinct myoclonic syndromes. The myoclonic epilepsy syndromes usually begin in childhood, but can begin at anytime during the lifespan. Absence seizures (petit mal) involve a loss of awareness lasting only seconds. These seizures are very brief but can happen multiple times per day. Sometimes these seizures can go undiagnosed for a time, as they seem so much like a quick daydream to observers. Atonic seizures involve a sudden, complete loss of muscle tone, often causing injuries due to falls. Atonic seizures are also known as “drop attacks” or “akinetic” seizures. Atonic seizures usually begin in childhood and last throughout adulthood. In contrast to generalized seizures, partial seizures only involve one hemisphere of the brain. The degree of consciousness retained during the seizure is one of the ways physicians classify the varying types of partial seizures. In simple partial seizures consciousness is retained, while in complex partial seizures consciousness is lost or impaired in some way. In certain seizures, the electrical activity moves from a localized area of the brain to the whole brain, causing secondary generalized seizures. Symptoms with partial seizures can include any type of sensory, motor or emotional response, including visual and auditory hallucinations.[iv] Partial seizures, unless they generalize, usually last less than 2 minutes. Because of the wide variety of symptoms involved in partial seizures, some people may even find them pleasant. The huge variation in seizure type is why epilepsy is considered an assortment of different syndromes. A person that has had 2 or more unprovoked seizures is typically checked for epilepsy. A complete neurological exam will by done by the physician. In addition, computerized tomography (CT scan) and magnetic resonance imaging (MRI) will be used to rule out tumors, growths, or other physical conditions in the brain that could be the cause of the seizure. If the results are negative, and no outstanding cause is found for the seizure, an electroencephalogram (EEG) will be done. An EEG is a machine that records the electrical impulses in the brain and is the most useful tool for diagnosis. Electrodes are attached to the patient’s head at key points. The electrodes pick up the signals of electrical discharges produces by the neurons in the brain. These signals are recorded on a piece of paper and called an EEG tracing. During an EEG test, a patient may be required to be sleep deprived, as the brain tends to be more unstable during sleep deprivation, thus brain wave abnormalities may be easier to spot. Flashing lights and hyperventilation done by the patient may also help the physician see these abnormalities. Certain patterns in brain waves indicate a tendency toward seizures. These tracings are called epileptiform waves or discharges. Certain epilepsy syndromes also have distinct patterns that show up during an EEG, which can be helpful to the diagnostician. If the physician does not find abnormalities on the EEG, more intensive monitoring is sometimes used. Video EEG is usually utilized for longer periods of time and the patient is videotaped so the care provider can compare the EEG tracings with behavior. In some cases, seizures are not the result of electrical discharges in the brain, but psychological in natures. These types of non-epileptic seizures will need an entirely different course of treatment. Because EEG tracings will look completely normal between seizures, it may take several EEGs, longer monitoring time, or the use of video EEG to determine the cause and type of seizures, and ultimately lead to a diagnosis of epilepsy. The motto for the treatment of epilepsy is “no seizures, no side effects”.[v] Treatment first includes appropriate first aid during a seizure, as injuries can occur during a seizure. Beyond initial first aid during a seizure, treatment spans options from pharmacological, nutritional, surgical, and/or any combination thereof. Typical first treatments include pharmacological methods, with are palliative. Many people will find that pharmacological methods are sufficient for seizure control. When seizure control is not achieved through medications, other options are usually explored. Vagus Nerve Stimulation (VNS) is used for partial seizures that are not controlled and is usually used in conjunction with medication. VNS works by sending regular electrical impulses to the brain through the vagus nerve, similar to a pacemaker. The ketogenic diet is another treatment option for those for whom medication has not worked. The diet is a high fat, low carbohydrate diet that keeps the body in a state of ketosis. Approximately 1/3 of children using the ketogenic diet become seizure free. Brain surgery may be an option for those with very clearly localized seizures that have failed other treatments. The seizures must begin in a portion of the brain that can be removed with harming important things like speech, eyesight or memory. This type of treatment can render many patients seizure free. Another lesser-known option for epilepsy patients are seizure response dogs.[vi] There is controversy about whether these dogs can actually “predict” a seizure, thus enabling the patient to get to a safe location, but at the very least, they are trained to assist during a seizure. Complementary medicine, such as acupuncture and Chinese medicine are sometimes used in conjunction with traditional treatment, but there is not much evidence to state whether this is a useful treatment. The prognoses are as varied as the many syndromes that compose the diagnosis of epilepsy. According to the World Health Organization, 70% of those newly diagnosed with epilepsy can be successfully treated with the “first line” treatment of antiepileptic drugs. Of those 70%, drugs can be withdrawn in about 70% of children and 60% of the adults. Those with partial complex seizures, on more than one AED, and adolescent onset show less favorable outcomes for remission. Sudden unexplained death in epilepsy (SUDEP) has been shown to be 24 times higher in those with epilepsy than in the general population and accounts for between 7-17% of deaths of those with epilepsy. Those patients with uncontrolled seizures and those with tonic clonic seizures are at the greatest risk for SUDEP. Quality of life continues to be a problem for many who suffer with epilepsy. Job security, side effects from AEDs, and social stigma continue to plague patients. The Epilepsy Foundation, with the CDC, funded a program called “Entitled To Respect”. This program included a national survey amongst teens. Of the 20, 000 young people surveyed, 49% did not know if seizures were contagious and 67% did not know what to do if someone had a seizure. In conclusion, continued research into treatment and raising public awareness about epilepsy will do much to improve the lives of those that suffer with epilepsy. 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