Seizures: Types, Diagnosis, and Treatment
Seizures are sudden, uncontrolled and uncharacteristic electrical disturbances in the brain that cause behavioural changes, often accompanied by loss of consciousness. Recurrent seizures are known as epilepsy.
Types of Seizures
The updated classifications from 2017 describe the many different seizures under two broad headings – the Focal Onset Seizures and Generalised Seizures.
- Focal Onset Seizures: Earlier referred to as partial-onset seizures, these result from abnormal electrical activity
in one particular area of the brain. - Focal Seizures with Impaired Awareness: A change or loss in consciousness or awareness occurs in these cases. The patient stares into space, does not normally respond to the environment, performs repetitive movements like chewing of the hand, walking in circles etc.
- Focal Seizures without Loss of Consciousness: These seizures can alter your emotions or even change the way things look, feel, taste and sound to you. But you never lose consciousness, hence these are the focal aware seizures as you are aware that you are experiencing a seizure. Additional signs may include involuntary jerking of any body part. Sensory symptoms like tingling, dizziness, flashing lights etc.
- Generalized Onset Seizures: These seizures start on both sides of the brain in a simultaneous fashion.
- Absence Seizures: Previously known as petit mal seizures, these seizures often occur in children. The characteristic features include staring into space, subtle body movements such as lip-smacking or blinking of the eye. The attacks come in clusters and can cause a brief loss of awareness.
- Tonic Seizures: Tonic refers to muscle stiffening. The attacks impact the muscles in the back, arms, or legs causing you to fall to the ground.
- Clonic Seizures: Repeated, rhythmic, jerking muscle movements occur during the convulsion. It’s likely to make you lose consciousness during the few minutes that it lasts.
- Tonic-Clonic seizures: The most dramatic kind amongst epileptic seizures, these were previously known as grand mal seizures. They result in abrupt loss of consciousness, stiffening of the body, vigorous shaking, loss of bladder control, biting of the tongue, etc.
- Myoclonic Seizures: Appears as sudden brief jerks or as twitches of the arms/legs.
- Atonic Seizures: These can cause you to suddenly collapse and fall down. Atonic seizures or drop seizures can cause loss of muscle control. Sometimes, it’s impossible to detect the beginning of a seizure, Because of the insufficient information available about how these start, they are referred to as the unknown onset seizures.
How to Diagnose Seizures?
Doctors can have a tough time diagnosing a seizure disorder accurately to ensure that the treatments that are resorted to are effective. The patient’s full medical history and events leading up to the attack are to be considered. This is because conditions like migraines, sleep disorders, and psychological traumatic stress are known to cause seizure-like symptoms.
Several lab tests are employed to detect the possibility of a future seizure and to rule out other possible conditions.
1. Neurological Exam
The doctor tests your motor abilities, behaviors, and mental functions to pinpoint problems in the brain and nervous system if any.
2. Blood Tests
Blood samples are collected to check for electrolyte imbalances, infections, genetic conditions, or blood sugar levels.
3. Electroencephalogram
In an EEG, electrodes are attached to the scalp to record the electrical activity of the brain that shows up as wavy lines on an EEG recording, thus revealing a pattern that helps predict future seizures. It also helps to rule out conditions that mimic epilepsy.
4. CT Scans/ MRI/ PET
All these tests help visualize active areas of the brain and any abnormalities thereof, like tumors.
5. Single-photon Emission Computerised Tomography
SPECT helps create a detailed 3D map of the brain’s blood flow activity happening during the course of a seizure.
6. Toxicology Screening
Patients are also tested for drugs, poisons or toxins.
How are seizures treated?
Treatments for seizures are cause-specific, thus enabling doctors to find an appropriate treatment. The goal is to prevent future attacks from happening with a therapy that has the best results and least side effects.
- Medication
Anti-seizure medication suited for every individual is sought after from amongst the options available. Your doctor will take into account the seizure frequency, your age and condition, and other factors while trying to find the right combination of medicines for you – one which has minimum side effects. The previous medical history will be evaluated to make sure the anti-epileptic medications don’t interact with the ones you are already taking. - Surgery
Surgeons locate the regions from where the seizure arises and remove the same in order to rid of the brain abnormalities. This procedure works best for people who suffer from seizures that originate from the same brain location. - Nerve Stimulation
Various nerve stimulations are tested out for effective seizure treatment
- Vagus Nerve Stimulation
This is a device implanted underneath the chest that stimulates the vagus nerve and sends signals to the brain to inhibit seizures - Responsive Neurostimulation
This is a device implanted on the brain surface or within the brain tissue that detects seizure activity and delivers electrical stimulation to detected areas, to stop the attack. - Deep Brain Stimulation
Electrodes implanted within the brain generate electrical impulses to regulate normal brain activity. These electrodes are attached to a pacemaker-like device placed under the skin; this helps in controlling the amount of deep brain stimulation produced
- Diet
A ketogenic diet is prescribed which is high in fat and low in carbohydrates. This is known to improve seizure control, on a much better scale as compared to the low glycaemic index diet or modified Atkins diet. Often treatments are late to start in case you get isolated attacks. For more info, reach out to us.
Dr. Arun G S | Consultant – Orthopaedics | Sahyadri Narayana Multispeciality Hospital, Shimoga