Seizures

Seizures are sudden, uncontrolled disturbances in the brain caused by abnormal electrical activity. Normally, brain cells communicate by sending electrical signals in an organized way. During a seizure, there’s a temporary malfunction where brain cells fire too rapidly and irregularly. This can cause a wide range of symptoms, from brief staring spells to violent shaking and loss of consciousness. Seizures can be a symptom of various medical conditions, including epilepsy (a chronic neurological disorder characterized by recurrent, unprovoked seizures), brain injury, infection, or temporary imbalances in the body.

Causes:

Seizures can be caused by a variety of factors, ranging from genetic predispositions to acquired brain conditions and temporary imbalances in the body. While some seizures have an identifiable cause, many cases of epilepsy are idiopathic (of unknown cause).

• Epilepsy: A chronic neurological disorder defined by two or more unprovoked seizures, or one unprovoked seizure with a high risk of more. The underlying cause of epilepsy is often complex and can be:
  • Genetic Factors: Certain gene mutations can increase susceptibility to seizures.
  • Structural Brain Changes: Abnormalities in brain structure, such as malformations, tumors, or scars from previous injuries.
  • Metabolic Disorders: Inherited conditions affecting the brain’s metabolism.
  • Immunological Conditions: Autoimmune encephalitis or other immune-mediated disorders affecting the brain.
  • Infections: Past infections like meningitis, encephalitis, or neurocysticercosis (a parasitic infection).
• Acquired Brain Conditions (Symptomatic Seizures):
  • Stroke: Damage to brain tissue from an ischemic or hemorrhagic stroke.
  • Traumatic Brain Injury (TBI): Especially severe head injuries.
  • Brain Tumors: Both benign and malignant tumors can irritate brain cells.
  • Brain Infections: Meningitis, encephalitis, abscesses.
  • Cerebral Palsy: A disorder of movement, muscle tone, or posture caused by damage that occurs to the immature, developing brain.
  • Alzheimer’s Disease or other Dementias: Can increase seizure risk in later stages.
• Temporary or Reversible Factors (Provoked Seizures):
  • High Fever: Especially in young children (febrile seizures).
  • Low Blood Sugar (Hypoglycemia): Can deprive brain cells of energy.
  • Severe Electrolyte Imbalances: Such as very low sodium (hyponatremia) or high calcium (hypercalcemia).
  • Alcohol or Drug Withdrawal: From chronic use of alcohol, benzodiazepines, or certain illicit drugs.
  • Drug Overdose or Toxicity: From certain medications (e.g., some antidepressants, stimulants).
  • Lack of Sleep (Sleep Deprivation): A common trigger for those predisposed to seizures.
  • Severe Head Trauma: Acute effects.
  • Eclampsia: A severe complication of pregnancy involving high blood pressure and seizures.

Symptoms:

Seizure symptoms vary widely depending on the type of seizure and the area of the brain affected. They can range from subtle changes in awareness to dramatic physical manifestations.

• Generalized Seizures (affect both sides of the brain):
  • Tonic-Clonic (Grand Mal):
    • Loss of consciousness.
    • Body stiffening (tonic phase).
    • Rhythmic jerking of limbs (clonic phase).
    • Loss of bladder/bowel control.
    • Biting the tongue.
    • Confusion or drowsiness after the seizure (postictal state).
  • Absence (Petit Mal):
    • Brief staring spells (seconds).
    • Loss of awareness.
    • No memory of the event.
    • Often occurs in children.
  • Myoclonic: Sudden, brief jerks or twitches of a muscle or group of muscles.
  • Atonic (Drop Attacks): Sudden loss of muscle tone, causing the person to fall.
  • Tonic: Sudden stiffening of muscles, often in the back, arms, or legs.
  • Clonic: Rhythmic jerking movements.
• Focal (Partial) Seizures (start in one area of the brain):
  • Focal Aware Seizures (Simple Partial):
    • Awareness is maintained.
    • Symptoms depend on the brain area affected:
      • Motor symptoms: Jerking of a limb, head turning.
      • Sensory symptoms: Tingling, numbness, visual disturbances, strange smells or tastes.
      • Autonomic symptoms: Sweating, flushing, stomach discomfort.
      • Psychic symptoms: Déjà vu, fear, anxiety.
  • Focal Impaired Awareness Seizures (Complex Partial):
    • Awareness is impaired or lost.
    • May involve automatisms (repetitive, non-purposeful movements like lip smacking, chewing, fidgeting).
    • Staring blankly.
    • Wandering.
    • Confusion during and after the seizure.

Diagnosis:

Diagnosing seizures involves a thorough medical history, neurological examination, and various tests to identify the type of seizure and its underlying cause.

• Detailed Medical History:
  • Crucial for diagnosis. The doctor will ask about the events leading up to, during, and after the seizure, eyewitness accounts are very helpful.
  • Inquire about past medical conditions, head injuries, family history of seizures, and medication use.
• Neurological Examination: To assess mental status, motor function, sensory function, reflexes, and coordination to look for any abnormalities that might point to a brain disorder.
• Electroencephalogram (EEG):
  • The most common test for diagnosing seizures. It measures electrical activity in the brain.
  • Electrodes are placed on the scalp to record brain waves. Abnormal patterns can indicate seizure activity.
  • May be performed as a routine EEG (20-40 min), sleep-deprived EEG, or prolonged video-EEG monitoring (for several days in a hospital setting).
• Imaging Tests: To look for structural abnormalities in the brain.
  • MRI (Magnetic Resonance Imaging) of the Brain: Preferred over CT to provide detailed images of brain structures and detect tumors, lesions, malformations, or areas of stroke.
  • CT Scan (Computed Tomography): May be used in emergency situations to quickly identify bleeding or large structural issues.
• Blood Tests: To check for electrolyte imbalances, infections, liver or kidney problems, genetic conditions, or drug levels that could cause seizures.
• Lumbar Puncture (Spinal Tap): If a brain infection (e.g., meningitis, encephalitis) is suspected, a sample of cerebrospinal fluid (CSF) may be analyzed.

Treatment:

Treatment for seizures depends on the type of seizure, its cause, frequency, and severity. The primary goal is to prevent seizures or reduce their frequency and impact on quality of life.

• Anti-Epileptic Drugs (AEDs) / Anticonvulsants:
  • The most common treatment. These medications work by stabilizing electrical activity in the brain.
  • Examples: Levetiracetam (Keppra), Lamotrigine (Lamictal), Valproic Acid (Depakote), Carbamazepine (Tegretol), Oxcarbazepine (Trileptal), Topiramate (Topamax), Gabapentin (Neurontin), Phenytoin (Dilantin).
  • Dosage and type are individualized; may require trying several medications to find the most effective one with minimal side effects.
• Surgery (for refractory epilepsy):
  • Considered for patients whose seizures are not controlled by medications and whose seizures originate from a specific, resectable area of the brain.
  • Resective Surgery: Removal of the seizure-producing area of the brain.
  • Corpus Callosotomy: Severing the connection between the two brain hemispheres to prevent seizure spread.
  • Hemispherectomy: Removal or disconnection of a large portion of one hemisphere, usually for severe cases in children.
• Vagus Nerve Stimulation (VNS):
  • A small device is surgically implanted under the skin in the chest and connected to the vagus nerve in the neck. It sends regular electrical impulses to the brain to prevent seizures.
• Responsive Neurostimulation (RNS):
  • A device implanted within the skull directly on or in the brain, which detects abnormal electrical activity and delivers electrical stimulation to normalize it.
• Deep Brain Stimulation (DBS):
  • Electrodes are surgically implanted into specific areas of the brain and connected to a pulse generator to deliver electrical stimulation.
• Dietary Therapies:
  • Ketogenic Diet: A high-fat, low-carbohydrate, adequate-protein diet that forces the body to burn fat for fuel (producing ketones). Primarily used for children with refractory epilepsy, but also sometimes in adults.
  • Modified Atkins Diet or Low Glycemic Index Diet: Less restrictive alternatives to the ketogenic diet.
• Lifestyle Management:
  • Avoid Triggers: Identify and avoid individual triggers like sleep deprivation, excessive alcohol, flashing lights (for photosensitive epilepsy), or extreme stress.
  • Regular Sleep: Maintain a consistent sleep schedule.
  • Stress Reduction: Techniques like meditation, yoga.
  • Safety Measures: Take precautions to prevent injury during a seizure (e.g., avoiding heights, swimming alone).

Living with seizures or epilepsy requires ongoing management, often involving a neurologist or epilepsy specialist, to achieve seizure control and maintain a good quality of life.