Cerebral Vascular Disorders Overview

Cerebral Vascular Disorders

• Cerebral vascular disorders cause disease or damage to blood vessels, reducing or stopping oxygen and glucose flow to brain regions. Cell death occurs within 10 minutes of the interruption.
• Stroke (CVA): A sudden neurological event due to interrupted blood flow resulting in an infarct (dead/dying tissue) and penumbra (dysfunctional tissue surrounding the infarct). Treatment aims to save the penumbra.
• Cerebral ischemia: Disruptions to blood supply, including thrombosis (blood clot formation) and embolism (a clot traveling to a smaller vessel). Cerebral arteriosclerosis (thickening/hardening of arteries) can also contribute to ischemia. Transient ischemia, called cerebral vascular insufficiency, is temporary. Stroke is not a necessary consequence of vascular disorders. Small lesions often have good prognoses.
• Cerebral hemorrhage: Bleeding in the brain due to a ruptured blood vessel causing surrounding tissue damage. Prognosis is poor if the patient is unconscious for more than 48 hours.
• Angiomas: Congenital abnormally enlarged blood vessels, often affecting the middle cerebral artery's field. They can lead to stroke or inadequate blood flow distribution.
• Aneurisms: Weakness in a blood vessel wall, creating a localized bulge prone to bursting, causing intracerebral hemorrhage. Often cause headaches due to pressure on the dura mater.

Traumatic Brain Injuries (TBI)

• TBI: Commonly from accidents, sports or war. Damages brain function directly by disrupting blood supply, inducing bleeding, increased pressure and swelling, causing infection, or scarring.
• Open head injuries: Penetrating skull injury, often causes symptoms resembling surgical excision of a cortex area, but symptoms can spontaneously recover.
• Closed head injuries: A blow to the head resulting in variable impacts and tissue damage.
  • Coup: Bruise at the impact location due to the skull pushing inward.
  • Contrecoup: Bruise on the opposite side of the skull from impact's pressure.
  • Microscopic lesions: Nerve fiber twisting/cutting
  • Hematoma: Blood accumulation.
  • Edema: Brain swelling.

Recovery and Assessment

• Recovery varies, with the majority of cognitive recovery occurring in the first 6-9 months, even taking years. Poor cognitive outcomes are sometimes linked to brain stem damage.
• Behavioral assessment is crucial for measuring nervous system integrity, often using the Glasgow Coma Scale (GCS) and the length of post-traumatic amnesia (PTA) to gauge severity.
• Head injuries can affect brain function cumulatively; repeated concussions can lead to conditions like dementia pugilistica (DP) or chronic traumatic encephalopathy (CTE).

Epilepsy

• Epilepsy: A brain disorder characterized by seizures, which are spontaneous abnormal brain neuron discharges.
• Seizures classified as focal (begin in a single region) or generalized (occur bilaterally).
  • Partial seizures: Characterized by onset in one area of the neocortex, potentially spreading. Can have subjective experiences, automatisms, or postural changes.
  • Generalized seizures: Lack of a focal onset.
    • Tonic stage: Body stiffening, respiratory arrest
    • Clonic stage: Rhythmic shaking
    • Post-seizure stage: Loss of affect and confusion.
• Diagnosis often confirmed by EEG, though a significant portion of people with abnormal EEGs do not have epilepsy.
• Treatment focuses on controlling seizures using anticonvulsant drugs, and surgery for focal seizure cases. Tumors may require surgical removal.

Psychiatric Disorders

• Schizophrenia: A severe disorder with symptoms lasting at least 6 months including delusions(beliefs), hallucinations(altered perceptions), disorganized speech, and disorganized behavior.

Mood Disorders

• Major Depression: a disorder characterized by worthlessness, guilt, disrupted eating and sleep patterns, slowed behavior, and thoughts of suicide.
• Reactive/Endogenous Depression: Depression with a discernible cause (Reactive) or without a known cause (Endogenous).
• Bipolar Disorder: Alternating episodes of mania/hypomania (excessive euphoria) and depression.. Includes type 1 (also characterized by mania) and type 2 (characterized by hypomania).

Infections

• Infections: Invasion of the body by microorganisms leading to symptoms like encephalitis and abscess.
• Bacteria (e.g., meningitis) can lead to abscesses and are often treated with antibiotics.

Headaches

• Headaches: Pain localized within the skull, resulting from processes such as pressure, inflammation, displacement, or tension in various intracranial structures (e.g., dura mater, arteries).
  • Migraines: Recurrent headache attacks often with an aura (sensory disturbance like those experienced before the onset of a seizure)
  • Tension headaches: Contractions in head and neck muscles, a common type of headache, and often responsive to stress management.

Multiple Sclerosis

• Multiple Sclerosis (MS): Progressive disease damaging myelin causing nerve dysfunction and degeneration.
• Characterized by vision, muscular weakness, numbness, tremor, ataxia.
• Immune-system reactivity and neural degeneration is thought to be a driver.

Dementias

• Dementia: Acquired and persistent intellectual impairment marked by cognitive decline and impacting daily independence.
• Alzheimer's Disease: Most common form of dementia, characterized by progressive memory loss, including recent and long-term memories.
• Parkinson's Disease: This disease is characterized by both motor and cognitive deficits. Early symptoms include tremors, muscular rigidity, and involuntary movements, and later symptoms include postural issues, difficulty communicating, and slowed thinking. Dementia is also a potential feature.

Additional (Neurological) Disorders

• Neuritic plaques, and neurofibrillary tangles (tau protein) are pathological features of Alzheimer's disease.

• Huntington's disease: A genetic disorder affecting parts of the brain, specifically the basal ganglia, leading to motor impairments (chorea), cognitive decline, and psychological changes.

• Tourette syndrome: Characterized by motor and vocal tics (repetitive movements and sounds).

• Idiopathic Parkinson's: A degenerative disorder beginning after the age of 50, caused by diminished dopamine production, resulting in slow movement, rigidity, tremors, and related symptoms.

• Parkinson's induced by medications (e.g., antipsychotics) and/or related to other conditions can affect the brain and nervous systems and cause related symptoms.