Treatment of epilepsy
After confirming the diagnosis of epilepsy, patients should start taking an antiepileptic drug (AED). The choice is based on the type of epilepsy and the drug’s effectiveness, safety and characteristics. Each patient’s individual circumstances (age, occupation, other diseases, etc.) are also important factors to consider when selecting a medication.
Patients should follow some specific guidelines and lifestyle habits to help control their seizures:
Take medication according to the neurologist’s indications.
Get enough sleep and follow a regular sleep schedule.
Avoid alcohol consumption.
Do not do drugs.
Reduce stress levels.
Eat a healthy and varied diet and carry out suitable physical exercise.
Follow recommendations regarding activities such as driving which, in the case of active epilepsy, can imply a risk for the patient and other people.
Fever or certain medications can also trigger seizures. Before taking other medicines, you should check that they are suitable for use in patients with epilepsy and do not affect the antiepileptic drugs you may be taking.
Some patients notice a specific sensation before losing consciousness during a seizure. This feeling is called an aura. Patients eventually recognise their auras and should take precautions to avoid injuries (e.g., sit down).
To improve seizure control, it is essential to diagnose the type of seizure correctly (focal or generalised onset) and select the most appropriate treatments for each case.
Antiepileptic drugs can achieve long-term remission in 60–70% of patients, but some need to take a combination therapy. If the first medication is rejected due to intolerable side effects, a second drug is usually selected and again used in monotherapy. If the first drug is not quite effective enough, a second one is usually added in combination.
Whenever the second drug does not achieve seizure control, it may be considered a case of drug-resistant epilepsy and the patient should be referred to a specialist unit to assess if they are a candidate for other treatments such as surgery or neurostimulation. For cases where these treatments are not applicable, other drugs must be tried as they may prove beneficial for some patients.
The medical team will prescribe a medication and its dosage, assess the type of epilepsy, the frequency of seizures, age and other factors, all of which tends to be a complicated process. They will also find out whether the patient takes any other medications that could interact with the antiepileptic drugs.
The doctor will probably prescribe just one drug at a relatively low dose and then gradually increase it until the seizures are well controlled.
Following a period of 2 to 5 years without any seizures, the neurologist may recommend a controlled withdrawal of the medication, so long as they believe there is little risk of recurrence and the patient follows the appropriate precautions.
Epilepsy surgery is defined as a neurosurgical intervention that aims to alleviate drug-resistant epilepsy.
To determine whether a patient with drug-resistant epilepsy is a candidate for surgery they need to undergo a complicated presurgical evaluation involving video–EEG monitoring, a brain MRI (magnetic resonance imaging) and a neurological, psychiatric and neuropsychological assessment. In certain cases, functional neuroimaging tests (PET, SPECT, etc.), the Wada test or an invasive electrode study must be conducted. These are performed to evaluate if the advantages of an intervention outweigh the potential risks.
There curative procedures, generally associated with the removal of some brain tissue where seizures begin, and palliative procedures, which may reduce the number of seizures but do not usually eliminate them completely, such as vagus nerve stimulation. The expected benefits and potential negative effects must be identified for each individual; these will depend on the type of surgery, the type of epilepsy and the patient’s characteristics. New surgical techniques, such as MRI-guided laser surgery and stereo-EEG-guided thermocoagulation, have emerged in recent years. Radiosurgery can be used to treat lesions with locations that are difficult to access through conventional surgery, such as hypothalamic hamartomas.
Immunotherapy and epilepsy
Various autoimmune causes of epilepsy have been reported over the last few years. Many of these patients experience drug-resistant epileptic seizures, impaired memory or psychiatric problems. If this diagnosis is confirmed, it can be treated with immunomodulatory agents or immunosuppressants in combination with antiepileptic drugs.
Recently, the indication of everolimus, a type of immunosuppressive drug, has been approved in patients with refractory epilepsy associated with the tuberous sclerosis complex, due to its antitumor and antiepileptic effect.
A variety of complications can occur depending on the type of treatment used to control the epilepsy.
In the case of drug therapies, there are three types of adverse effect:
- Related to the central nervous system and dosedependent effects including: dizziness, nausea, instability, double vision, headaches, mood swings, behavioural changes and cognitive impairment.
- Idiosyncratic or unpredictable side effects, for example blood cell alterations, hepatitis and allergies.
- Foetal malformations and developmental delay. Antiepileptic drugs taken by pregnant mothers can lead to foetal malformations and developmental delay; therefore, the pregnancy must be planned correctly, including selection of the safest medicines for the mother and baby.
With respect to different immunosuppressants used to treat autoimmune epilepsy, such as corticosteroids, cyclophosphamide or everolimus, patients must remember that they will produce an immunodepressed state, so they should be particularly wary of potential infections and treat them as early as possible.
There are certain complications associated with the surgical procedures used to treat epilepsy, for instance, wound infections or central nervous system infections (meningitis, encephalitis), brain haemorrhages or stroke, and cerebrospinal fluid leaks.
Other complications depend on the type of surgery and the area operated on. These risks must be discussed at length with the patient and their family.
StereoEEG-guided radiofrequency thermocoagulation. After completing a depth electrode study (stereoEEG), the technician selects the electrodes involved in seizure onset and increases their temperature, thus burning a small area around the contacts. However, this procedure does not exclude the need for a subsequent open operation. It is usually indicated for small lesions that are hard to access with normal surgery (e.g., periventricular heterotopias).
MRIguided stereotactic laser-induced thermotherapy. A potentially large area of brain tissue is destroyed with an MRIguided laser assisted by real-time probe tracking in order to control the temperature. In the last few years, it has been used extensively in the United States to treat multiple pathologies (mesial sclerosis, heterotopias, hamartomas, cavernomas). However, its exact indications are still unclear. This procedure has not yet been approved in the European Union.
Brain stimulation. In Spain, our clinic is a pioneer in the use of neurostimulation techniques that can help reduce the number of seizures in certain patients who would not benefit from surgery or continue to experience seizures after an operation. The most used techniques are deep brain stimulation of the vagus nerve, the external trigeminal nerve or the anterior nucleus of the thalamus.