Epilepsy Surgery
Epilepsy Is…
A disorder of the central nervous system, particularly the brain, which means people sometimes have seizures. Epilepsy means you are likely to have more than one seizure. Not everyone who has a seizure has epilepsy.
What Causes Epilepsy?
People often wonder what causes epilepsy. In about 50 per cent of cases, doctors cannot find a cause – epilepsy just seems to come out of the blue. In the other 50 per cent of the cases, the cause can be identified, just like any injury or illness to the brain.
Epilepsy is widespread and it can affect anyone. People with epilepsy come from all sections of the community and all nationalities. Two in every 100 Australians have some form of epilepsy. Although epilepsy can begin at any age, most people with epilepsy have their first seizure during childhood. About two thirds of people with epilepsy have had their first seizure by the time they complete their primary school years. This means that about 50,000 primary school students throughout Australia have epilepsy.
A Seizure Is…
For us to be alive, we all have electrical activity taking place in the brain. The electrical activity is important in sending messages from the brain to other parts of the body. A seizure happens when there is a sudden burst of the electrical activity. Depending on which part of the brain is involved, the seizure will affect different parts of the body or what the body does.
A seizure may affect someone’s behaviour, their consciousness (level of awareness), their senses or their movements. Seizures usually don’t last very long, a few minutes at the most. The same person can have more than one type of seizure. The pattern of seizure may change over time or the seizures may stop altogether.
Types Of Seizures:
body goes stiff
person becomes unconscious
they may fall
then the muscles jerk
there may be lots of saliva
there may be choking noises
the face may go grey or blue
This usually lasts one to three minutes. It may look frightening, but the person is not in pain and will breathe normally again after the seizure. They may have a headache or be tired or confused afterwards.
First Aid – Do not restrain the person. Protect the person from obvious injury by placing something soft under their shoulder and head. As soon as possible roll the person onto their side to keep the airway clear. Stay with, protect and reassure the person until fully recovered.
If the seizure lasts more than 5 minutes or another tonic-clonic seizure commences, call an ambulance immediately.
During a Seizure:
DO
-Keep calm
-Clear space and remove dangerous objects
-Protect the person’s head, for example, by using a cushion or rolled up sweater.
-Call an ambulance if the seizure lasts more than 5 minutes.
DON’T
-Put your fingers or anything else in the person’s mouth. A person cannot swallow their tongue.
-Try to restrain movement.
After the Seizure:
DO
-Roll the person over onto their side with the head tilted back gently and chin extended.
-This will prevent the tongue falling back and keep the airway open.
-Offer support and reassurance when the person returns to consciousness.
-Get medical help if the seizure lasts for more than five minutes or other one begins.
person suddenly loses awareness
they just stare straight ahead, as if daydreaming
their eyelids may flutter or their eyes roll back
they won’t fall over
when the seizure is finished, the person suddenly stops staring and goes back to what they were doing the person does not know it has happened
This usually lasts one to ten seconds, and may happen many times a day.
No first aid is required.
the person’s level of awareness is changed, so they may act like they are in a trance
they may do things for no reason, in a repetitive way, for example
mumbling, wandering, pulling at clothes, chewing movements, lip smacking, repeating activities automatically.
This usually lasts two to four minutes, sometimes longer, and the person may feel confused and unsure of their surroundings after the seizure. Do not leave the person unattended until they have recovered.
Call an ambulance if the jerking movements last for more than 5 minutes, if the person has injured themselves or they become irrational.
What Type of Management is Required for People with Epilepsy?
Suitable control of seizures with anti-convulsants (medication). Understanding their type of epilepsy, the warning signs, triggering factors and a change of life style to accommodate their condition.
Surgical options for the treatment of patients with epilepsy not controlled by medication is increasingly successful. Suitable candidates may be offered surgery.
Treatment Through Surgery
Brain surgery can be a successful way of treating epilepsy. Surgery is most likely to be considered when someone with epilepsy:
-
Has already tried the standard medicines without success (or has bad reactions to them).
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Has seizures that always start in just one part of the brain.
-
Has seizures in a part of the brain that can be removed without damaging important things like
speech, memory, or eyesight. -
Surgery for epilepsy is a delicate, complicated operation. It must be performed by a skilled, experienced surgical team. It is usually done at special medical centres rather than at local hospitals. In addition to operations that remove a small part of the brain where seizures begin, other procedures may be done to interrupt the spread of electrical energy in the brain.
People who are going to have epilepsy surgery may have several special tests first. In some cases, electrodes have to be implanted in a separate operation to locate seizure sites deep in the brain. Sometimes these tests take days or even weeks to complete.
Patients may be awake during part of the operation. This is possible because the brain does not feel pain. Having the patient awake helps the doctors make sure that important parts of the brain are not damaged.
Afterwards, some seizure medications may have to be continued, usually for a year or two. Then, if no further seizures occur, the medicine may be slowly withdrawn. At this point, chances of living free of seizures and free of medication are good. However, many people will have to continue with medication and some do not benefit from surgery.
Surgery
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If pre-surgical evaluation suggests that surgery may be beneficial, patients may undergo one of the following procedures:
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Anterior temporal lobectomy – removal of the anterior temporal lobe including the medial temporal
structures; -
Extratemporal resection – removal of epileptogenic cerebral cortex outside the anterior temporal lobe;
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Functional hemispherectomy – removal of the majority of one cerebral hemisphere and functional disconnection of the remainder of the hemisphere in patients with severe unilateral damage and intractable epilepsy
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Hemispherotomy – a recent modification of hemispherectomy in which the damaged, epileptogenic hemisphere is disconnected rather than removed. It is a much shorter operation than hemispherectomy, and is ideally suited for patients with significant atrophy of the damaged hemisphere. Approximately 60% of previous candidates for hemispherectomy may undergo this procedure.
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Corpus callosotomy – sectioning of the corpus callosum to disconnect the two hemispheres and prevent the spread of seizures from one hemisphere to the other
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Multiple subpial transection – transection of the cortex without removal when the epileptogenic zone is in a functionally important area.
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Vagal nerve stimulation – involves implantation of a stimulating electrode around the left vagal nerve and attaching it to a pulse generator which is implanted under the skin just below the collar bone. The pulse generator is programmed so that it may be turned on or off at specified times and so that the amplitude and frequency of stimulation can be modified as indicated.
What is a Seizure?
“An abnormal discharge of electrochemical activity in the Brain.” These can last from a few seconds to a few minutes
What is Epilepsy?
It is a disruption of brain function resulting in a person having recurrent seizures.
Who Gets Epilepsy?
Anyone. Approximately 2% of the population may have epilepsy of varying types.
What Causes Epilepsy?
Approximately 50% of diagnosed epilepsy is of an unknown source (idiopathic or primary). Others (called secondary) may be from childhood illnesses, strokes, tumours, head injuries, birth defects etc.