Understanding Tumors and Seizures

Neurological Disorders

• 680,000 individuals are living with brain tumors.
• Tumors and seizures can occur separately.

Tumors

• Mass of cells that grow uncontrollably and serve no useful purpose.
• Some are cancerous (malignant) and some are not (benign).
• The key distinction between malignant and benign tumors is encapsulation.
• An encapsulated tumor has clear boundaries between the tumor cells and surrounding tissue.
• Malignant tumors spread by infiltrating surrounding tissue.
• Tumors can spread via metastases.
• Tumors break off, travel through the vascular system (bloodstream), and grow in other areas of the body.
• Brain damage due to tumors occurs through compression or infiltration.
• Compression involves a benign tumor filling space, pushing against brain tissue.
• Infiltration refers to the tumor cells directly destroying brain tissue. Alternatively, this can cause hydrocephalus, a build-up of cerebrospinal fluid.
• Brain tumors can originate in the brain itself, or from other parts of the body that metastasize to the brain.
• Serious types:
  • Metastases (cancerous spread from other organs)
  • Gliomas (cancerous tumors arising from glial cells; usually very malignant and grow quickly)
  • Meningioma (encapsulated, benign tumor arising from the dura mater and arachnoid membrane)

Causes of Tumors

• Originate from cells in the brain or spread from metastases elsewhere.
• Most serious types as mentioned previously (metastases, gliomas, meningioma).

Treatments

• Some tumors respond to radiation treatment.
• Radiation can destroy the tumor or be targeted via radiosurgery.
• Chemotherapy is another treatment option; affecting rapidly dividing cells like cancerous cells; causes side effects like hair loss and reduced blood flow.
• Surgical interventions (surgical excision or removal)

Seizures

• Brief periods of excessive neuronal activity.
• Muscle convulsions can occur.
• Not all seizures cause convulsions; many are subtle.
• Partial seizures only affect a specific part of the brain.
• Generalized seizures involve a large portion of the brain.
• Seizures can result in brain damage.
• Types:
  • Simple Partial Seizures: Changes in consciousness without loss
  • Complex Partial Seizures: Loss of consciousness
  • Generalized Seizures: Includes motor seizures (tonic-clonic, grand mal)

Seizure Causes

• Common causes are scarring, injury, stroke, developmental abnormalities or irritating effects of tumors.
• Genetic factors influence seizure disorders
• Genes controlling ion channel production

Cerebrovascular Accidents (Causes)

• Types of strokes:
  • Hemorrhagic Strokes: caused by bleeding within the brain due to malformed blood vessels or high blood pressure
  • Ischemic Strokes: caused by blocked blood vessels (thrombi or emboli)
  • Thrombi are blood clots forming in blood vessels.
  • Embolus is a piece of material that forms in one part of the vascular system and blocks blood flow elsewhere.
• Treatments: -Hemorrhagic: medication for lowering blood pressure or surgery -Ischemic: treatment to dissolve or remove clots, or anticoagulant drugs -Any clots can cause a bacterial infection that can be treated with antibiotics

Traumatic Brain Injuries (TBI)

• Open-head injuries involve objects penetrating the skull.
• Closed-head injuries are impacts without bone fracture.
• Chronic Traumatic Encephalopathy (CTE) arises from repeated head trauma (similar to dementia)

Disorders of Development

• Toxic chemicals, exposure during pregnancy (alcohol, other toxins)
• Genetic factors are important in intellectual disability

Inherited Metabolic Disorders

• These disorders impact enzyme synthesis within the body.
• Some disorders like PKU (phenylketonuria) result from enzyme deficiencies that affect neurological development.

Transmissible Spongiform Encephalopathies

• Infectious brain diseases resulting in brain damage.
• TSEs include Mad Cow disease (BSE).

Parkinson's Disease

• Progressive neurodegenerative disorder affecting motor neurons.
• Degeneration associated with abnormal proteins (Lewy bodies)
• No genetic origin of Parkinson's

Amyotrophic Lateral Sclerosis (ALS)

• Degenerative disorder affecting motor neurons.
• Symptoms appear gradually such as muscle weakness and spasms or atrophy, paralysis affecting speech as well as purposeful movement.
• 5 out of 100,000 are affected

Multiple Sclerosis (MS)

• Autoimmune disease affecting myelin sheaths, disrupting nerve signals.
• MS shows symptoms that increase and decrease in severity.

Dementia (e.g., Alzheimer's Disease)

• Progressive loss of cognitive function and memory.
• Characterized by the accumulation of abnormal proteins (amyloid plaques, neurofibrillary tangles) in the brain.

Herpes Simplex Virus, Rabies, Viral/Bacterial Meningitis

• Infections of the nervous system characterized by inflammation, infection, and resulting damage.
• Various types of viruses and bacteria lead to inflammation of the protective membranes of the brain (meningitis).
• Symptoms can include: headaches, fever, stiff neck, and sometimes convulsions or loss of consciousness.

Korsakoff's Syndrome

• Neurological disorder resulting from severe vitamin B1 (thiamine) deficiency, often associated with chronic alcohol abuse.
• Includes anterograde amnesia (inability to form new memories)