When people present with symptoms that lead to the diagnosis of a brain cavernoma, half of the time it’s due to one or more epileptic seizures. But what exactly are seizures, how do cavernomas cause them and what are the main triggers? We’ve put together this guide to answer some of the most common questions.
If you thinkyou are experiencing epileptic seizures, or require medical attention, please contact your doctor.
What is an epileptic seizure?
Our brain cells are constantly communicating with one another via electrical signals. “In epilepsy the electrical signals in the brain become scrambled and there are sometimes sudden bursts of electrical activity. This is what causes seizures” (https://www.nhs.uk/conditions/epilepsy/).
It is important to note that there are several triggers of seizures, not all of them in the brain. Some seizures can be caused by a reaction to medication, low blood sugar (hypoglycemia) or even, in very small children, a very high temperature. In this discussion, we are concerned with seizures that are caused by cavernoma and which therefore start in the brain.
What’s the difference between a seizure and epilepsy?
A seizure is an individual incident of abnormal electrical activity in the brain, while epilepsy is a chronic neurological condition that causes repeated seizure activity: it is only when seizure activity becomes recurrent, or when a doctor believes there is a high chance of future seizures, that the condition is called epilepsy. A person can have a seizure without having epilepsy, but you cannot have epilepsy without having seizures.
How does a cavernoma trigger seizures?
A cavernoma triggers seizures because (a) the cavernoma itself puts pressure on the neurons (nerves) surrounding it, and (b) the blood staining of the brain that surrounds the cavernoma disturbs the electrical activity of the neurons and this can trigger a seizure.
What are the different types of seizure?
When most people think of seizures and epilepsy they think of flashing lights and a person falling to the floor and shaking. While these descriptors can certainly be true for some people, according to Epilepsy Action, there are around 60 different types of seizures – a person may have more than one type. Epilepsy isn’t one disease or condition; there are several types of epilepsy, each with different triggers, symptoms and patterns.
Depending on what area of the brain is affected, seizures are experienced in different ways. Some people might lose consciousness, others might have their consciousness affected and feel confused, while others remain alert and aware. Some people might experience uncontrollable movements, jerks or sensations, while others may become rigid, fall to the ground and shake.
The different types of seizures can be divided into different categories;
Both Epilepsy Action and Epilepsy Society websites contain very detailed descriptions and explanations or each of these seizure types.
How is epilepsy diagnosed?
Doctors are often able to diagnose epilepsy from detailed descriptions of seizures. There is no one specific test that can prove that a person has epilepsy, but doctors may arrange for an EEG (electroencephalogram) to be performed in order to gain more information on the possible type of seizure/s. An EEG is a painless test that records brain activity. Small sensors are attached to the scalp which detect and record the electrical activity in the brain. These recordings are then analysed by a doctor.
It can be helpful for both you and your doctor to keep a seizure diary and record your seizure activity over time.
Can medication help?
The best way to prevent further seizures is by taking epilepsy medication. While it does not cure epilepsy, medication is the main treatment for epilepsy. Anti seizure medication (ASMs), also known as anti-epileptic drugs (AEDs) work by targeting the chemicals in the brain that control electrical activity.
ASMs are prescribed by your doctor with the main aim to prevent all seizures using the lowest possible dosage and the least side effects. There are many different ASMs/AEDs and it is not unusual for one drug to not be sufficiently effective and for your clinician to recommend a different one.
Your doctor will always start you on a low dose to allow your body to get used to the medication, and build up slowly over time until seizures are considered well-controlled.The time it takes to get seizures under control varies widely; some peoples’ seizures are controlled with the first medication they try, but for others the process of reaching a maintenance dose can take weeks or months. It is important to follow the advice given by your doctor for starting, stopping or changing medication or dosage.
To learn more about types of epilepsy medication in the UK, generic versus brand name ASMs, and how to get them, click here.
What if medication doesn’t stop my seizures?
Unfortunately, in one third of people with epilepsy, some seizures do not respond well to anti-seizure medication. This is often referred to as ‘refractory’, ‘uncontrolled’ or ‘intractable’ epilepsy.
If you and your doctor have tried two or more different types of ASMs and you are still having seizures you should be referred to a specialist epilepsy centre for further help. Specialists will try different ways to control your seizures and may suggest different types of treatment.
What kind of things can trigger seizures?
Some people might find that their seizures occur in a pattern, or are more frequent, under particular circumstances. These are called ‘triggers’ – they do not cause seizures, but they make them more likely. Not everyone will have seizure triggers and the conditions that trigger one person can be different for earch person. It can be a good idea to keep track of any factors or conditions that you notice before any seizures to help identify any patterns of seizure activity over time.
Some of the most commonly reported seizure triggers are;
- Time of day (morning or night seizures)
- Not taking medication
- Lack of sleep or tiredness
- Feeling stressed or anxious
- Alcohol or recreational drug use
- Monthly hormonal cycle
- Not eating well, skipping meals or waiting long times between meals.
- Other illness (with and without fever)
We recommend keeping a seizure diary to help determine any triggers or particular patterns; after every seizure, take note of what you were doing and how you were feeling beforehand. This way, you may be able to identify a pattern or learn to lower the risk of seizure from specific triggers.
Should I drive if I have a seizure or epilepsy?
If you have a seizure or are diagnosed with epilepsy as a result of your cavernoma you must stop driving and inform the DVLA as soon as you can. Having seizures or epilepsy does not automatically mean that you will not be allowed to learn how to drive or lose your licence forever – this is not always the case.
Please consult our ‘Driving and epilepsy’ guide for everything you need to know.
What are the risks of seizure from cavernoma in pregnancy?
If you have epilepsy or are concerned about the risk of seizures, it is important that your neurologist or epilepsy nurse specialist advises you early on in your pregnancy alongside the antenatal care provided by your obstetrician. A neurologist or epilepsy nurse specialist will know whether you should adjust the dose of your anti-epileptic drugs and will be able to give you other guidance. Women with epilepsy should take folic acid at the higher dose of 5mg daily, to reduce the risk of the baby developing birth defects such as spina bifida.
For more information, check out our ‘Pregnancy, childbirth and cavernoma’ information booklet.
For more information and support please contact our helpline on 01305 213 876.