Lecture 9.1 MJ slide Flashcards
What is the normal flow of CSF?
1) Choroid plexus within ventricles secretes CSF
2) CSF fills subarachnoid space, cushioning the brain and spinal cord
3) Arachnoid granulations resorb CSF
1) Define hydrocephalus
2) What causes it?
1) Accumulation of excessive CSF within the ventricular system
2) Impaired CSF flow or resorption
When are 2 times hydrocephalus can occur? What happens in each?
1) Before suture closure: enlargement of head
2) After suture closure: expansion of ventricles
1) Define herniation
2) Describe how it happens
1) Displacement of brain tissue from one compartment to another
2) Secondary ↑ ICP → pushes brain across rigid dural folds (falx/ tentorium) → compression & ↓ blood supply → more swelling and herniation
List the 3 types of herniation
1) Subfalcine (cingulate) herniation
2) Transtentorial (uncal or uncinate) herniation
3) Cerebellar Tonsillar herniation
Transtentorial (uncal or uncinate) herniation:
1) What is occurring?
2) What are 2 unique Sx?
1) Uncus of temporal lobe pressing against midbrain
2) Ipsilateral pupillary dilation
Contralateral hemiparesis
Cerebellar Tonsillar herniation:
1) What is it?
2) What does it cause? (important)
3) What are a concern for this reason?
1) Cerebellar tonsils press against medulla
2) APNEA AND ASYSTOLE
3) Space-occupying lesions in the posterior fossa
What is the clinical term for Cerebrovascular Disease?
Stroke
Cerebrovascular Disease
1) What are strokes?
2) What follows loss of blood supply? What are the 2 types?
1) Acute-onset neurologic deficits resulting from hemorrhagic or obstructive vascular lesions.
2) Cerebral infarction; widespread or focal
Cerebrovascular Disease
1) What is the most common type of focal cerebral infarct? Explain
2) What are primary intraparenchymal hemorrhages mostly due to?
3) Spontaneous subarachnoid hemorrhage are caused by what?
1) Embolic → subsequent dissolution of the embolus and reperfusion; a nonhemorrhagic infarct can become hemorrhagic.
2) HTN
3) A structural vascular abnormality, such as an aneurysm or arteriovenous malformation
Trauma of the CNS:
1) What is a concussion? What can they lead to?
2) Multiple concussions lead to neurodegenerative process; this is called?
3) What are brain contusions? What are the 2 kinds?
1) Reversible altered brain function with or without LOC
2) Chronic traumatic encephalopathy
3) Refers to tissue damage to the brain secondary to impact
-Coup or countercoup (or both)
Trauma of the CNS: What can cause Diffuse Axonal Injury? How can it present?
Rapid displacement of the head and brain can tear axons, often causing severe, irreversible neurologic deficits – death.
1) What can myelin disorders lead to?
2) What is the most common myelin disorder? What is it? Who does it affect most and how does it present?
3) What are genetic disorders in which myelin production or turnover is abnormal called?
1) Widespread and severe neurologic deficits.
2) MS; autoimmune attack on myelin sheath, young adults. relapsing-remitting course → eventual progressive accumulation of neurologic deficits
3) Leukodystrophies
1) Less common forms of immune-mediated demyelination often follow what?
2) What causes them?
1) Infections (and often are more acute illnesses)
2) Thought to be a product of immune response and not actual infectious spread
1) Neurodegenerative diseases cause symptoms that depend on the ___________ of brain involvement.
2) Give 4 examples
1) pattern
2) Cortical disease → cognitive change, alterations in personality, and memory disturbances; (Alzheimer Disease)
Basal ganglia disorders → movement disorders (Parkinson Disease and Huntington Disease)
Cerebellar disease → ataxia (spinocerebellar ataxia)
Motor system → weakness and difficulty swallowing (Amyotrophic lateral sclerosis)
Neurodegenerative Disease:
1) Which is associated with cognitive change, alterations in personality, and memory disturbances; (Alzheimer Disease)?
2) What disorders are movement disorders (like Parkinson and Huntington)
1) Cortical disease
2) Basal ganglia disorders
Cerebellar disease → ataxia (spinocerebellar ataxia)
Motor system → weakness and difficulty swallowing (Amyotrophic lateral sclerosis)
Alzheimer Disease
1) It is the most common cause of dementia in adults and a ____________ abnormality.
2) What 2 things appear well in advance of cognitive change?
1) Fundamental
2) Plaques and tangles
Explain the pathogenesis of Alzheimer disease
Accumulation of Aß (plaques) and tau (tangles) proteins and amyloid in brain → neuronal injury →neuronal death → inflammation
What is Parkinson’s characterized by? (4 things)
1) Tremor
2) Rigidity
3) Bradykinesia
4) Instability
Describe the pathogenesis/ associations of Parkinsons (hint: 3 main things)
1) Protein accumulation
Lewy body inclusions can’t be cleared by autophagy
2) Mitochondrial abnormalities
3) Neuronal loss
Amyotrophic Lateral Sclerosis:
1) How does it affect lower motor neurons? What Sx does this cause?
2) How does it affect upper motor neurons? What Sx does this cause?
1) LMN death (spinal cord & brain stem)
Weakness and fasciculations
1) UMN death (Betz cells; motor cortex)
Paresis
Hyperreflexia
Spasticity
Babinski positive
“lateral sclerosis”- degeneration of corticospinal tracts
1) Describe the clinical progression of AML (Amyotrophic Lateral Sclerosis)
2) What is the Pathogenesis?
1) Subtle, asymmetric distal weakness → respiratory muscles
2) Only 10% familial, rest are sporadic
a) Familial versions -Mutations cause misfolded SOD1 proteins →trigger unfolded protein response→ apoptotic death of neurons
b) Sporadic not as well understood.
Chronic Inflammatory Dermatoses: List 3
1) Psoriasis
2) Lichen planus
3) Lichen simplex chronicus
Chronic Inflammatory Dermatoses: Psoriasis
1) What mediates it? What type of disease is it?
2) Is this a “self” or non-self issue?
3) What are the common sites?
1) T-cell mediated inflammatory disease, presumed to be autoimmune
2) Unclear if the antigens are environmental or self antigens
3) Elbows, knees, scalp, lumbosacral areas, intergluteal cleft, glans penis and vulva (extensor surfaces)
Chronic Inflammatory Dermatoses: lichen planus
1) What are the 5 Ps?
2) What is the mechanism?
1) Pruritic, purple, polygonal, planar papules and plaques
2) CD8+ cytotoxic reaction against antigens in the basal layer
Chronic Inflammatory Dermatoses: lichen simplex chronicus
1) What does it look like?
2) What causes it?
1) Roughening of the skin → much like lichens on a tree
2) Usually from repetitive trauma like rubbing or scratching.
Infectious Dermatoses: What are the 3 causes?
Bacterial, fungal, or viral
Infectious Dermatoses: Bacterial
1) What is the pathogenesis?
2) When can P. aeruginosa occur?
1) Superficial –impetigo → Staph aureus or step pyogenes → evolves into a larger lesion with honey-colored crust
2) Deep dermal from puncture
Infectious Dermatoses
1) When is P. aeruginosa an issue for this?
2) What fungus may be life-threatening? When?
3) How can this happen virally?
1) Deep dermal from puncture
2) Aspergillus in immunocompromised
3) HPV subtypes → verrucae → proliferative lesions of squamous epithelial cells
Blistering (Bullous) Disorders:
1) What is it? What type of rxn?
2) What are the 3 subtypes?
1) Autoimmune (Type II reaction, IgG) blistering resulting from loss of normal intercellular attachments within the epidermis and squamous mucosal epithelium.
2) Pemphigus vulgaris (most common)
Pemphigus foliaceous
Paraneoplastic pemphigus associated w/ internal malignancy
Blistering (Bullous) Disorders
1) What causes Bullous Pemphigoid?
2) What causes Dermatitis Herpeteformis? What is it characterized by?
1) Linear deposition of autoreactive IgG and compliment in the epidermal basement membrane
2) Autoimmune (IgA) blistering associated with gluten sensitivity; pruritic grouped vesicles and papules
