Review Questions 2 Flashcards
A neurologic disorder characterized pathologically by loss of neurons in Substantia Nigra
Parkinson Disease
- Tremors AT REST
- Muscular rigidity
- Expressionless/Mask-like Face
- Emotional lability (depression/dementia)
- Drooling
- Very little blinking
- Cog-wheel rigidity
Clinical features of Parkinson Disease
Which neurotransmitter is deficient in Parkinson Disease?
Dopamine (produced by Substantia Nigra, are responsible for relaying messages that plan/control body movement)
When does Parkinson Disease usually appear?
- 6th decade (50-59 yrs)
- 8th decade (70-79 yrs)
When does Parkinson Disease incidence decline?
After 80 yrs old
What % of N. America will develop Parkinson Disease?
More than 2%
Is not genetic, sex, or racial
Parkinson Disease
Vast majority of cases of Parkinson Disease are due to which etiology?
Idiopathic
Genetic factor of Parkinson Disease
- Rare, autosomal dominant
- Early onset
- Point mutation of chromosome 4
What part of the brain is affected by Parkinson Disease?
- Substantia Nigra (relays info to the Basal Glanglia) through dopaminergic synapses
What group of brain tumors account for 60% of primary intracranial neoplasms?
Gliomas (tumors of neuroectodermal origin)
Corticol disease (outside of brain affected)
Alzheimer Disease
- Most common cause of dementia in elderly (1/2 of all cases)
- Before what age is the prevalence 1 - 2%?
- After what age is prevalence over 10%
Alzheimer Disease
- under 65 yrs
- over 85 yrs
Which chromosome has the Alzheimer gene?
21
Which sex is affected twice as often by Alzheimer Disease?
Women
What % of Alzheimer Disease has a familial variant (genetic)
5 - 10%
Etiology of Alzheimer Disease
Idiopathic, but there is suspicion for viral cause which is not proven
Significant advances of what pathogenesis have been made for Alzheimer Disease?
Beta-protein amyloid deposition in senile plaques
located in areas of the cerebral cortex and are linked to intellectual function and are a constant feature of Alzheimer Disease
Senile Plaques
What 3 microscopic features are needed to dx Alzheimer Disease?
- Senile Plaques
- Neurofibrillary tangles
- Beta-protein Amyloid Angiopathy
Origin of deposits in the brain
Beta-protein amyloid (found in walls of cerebral blood vessels)
- Paired helical filaments
- abnormal form
- microtubule protein
- proper axonal transport
Neurofibrillary tangles
What happen to the Gyri and Sulci w/ AD?
- Gyri narrow
- Sulci widen
- Which parts of the brain are affected by AD?
- Which part is spared?
- Bilateral cortical atrophy of frontal, temporal, parietal, and hippocampal cortices
- Spares occiput
Brain loses how many grams over how many years?
- 200 grams
- 3 - 8 years
Which part of the brain is the best place to examine for the 3 microscopic findings to dx AD?
Hippocampus
discrete spherical masses of silver-staining neuritic processes surrounding a central amyloid core. Found predominantly in the hippocampus and amygdala, as well as the cortex.
Senile (neuritic) Plaques
- bundles of paired, helical filaments in the cytoplasm of cortical neurons or hippocampal pyramidal cells that displace or encircle the nucleus (flame cells).
- Are dramatically demonstrated on silver stains and are commonly found in the cortex, hippocampus, and the amygdala.
Neurofibrillary Tangles
found within cerebral blood vessels seen with congo red stains.
Amyloid Angiopathy
Clinical assessment + modern radiologic methods allow acurate dx in what % of cases of AD?
80 - 90%
What is the usual cause of death of a bedridden patient with late stage AD?
Terminal bronchopneumonia
What is the most common clinical presentation of someone w/ an ependymoma of the 4th ventricle?
Hydrocephalus, secondary to progressive obstruction of the 4th ventricle rather than invasion of the pons or medulla.
Arises in white matter, usually in cerebral hemispheres in adults
Oligodenroglioma
5 - 15% of gliomas are which one?
Oligodendroglioma
- Well circumscribed
- Gelatinous
- Grey masses
- often w/ cysts
- focal hemorrhage
- calcifications seen in 90% of tumors
oligodendroglioma
- Slow growing tumor due to absence of mitotic figures and necrosis
- Have a better prognosis than patients w/ astrocytomas
- Several yrs of neuro complaints (seizures)
Oligodendroglioma
- Accounts for 20% of all brain tumors in children
- Arises exclusively in the cerebellum
Medulloblastoma
Small, round, blue cell tumors of childhood
(neuroblastoma, retinoblastoma, Ewing’s Sarcoma)
Medulloblastoma
Where do medullosblastomas infiltrate the brain?
Vermis of the cerebellum (aggressively and frequently disseminates through CSF)
Well circumscribed, gray, friable
Medulloblastoma
A child with a medulloblastoma will present with which of 2 things?
- Cerebellar dysfunction
- Hydrocephalus
What is the most common genetic alteration of a medulloblastoma?
Loss of material from short arm of chromosome 17
Highly malignant, but is extremely radiosensitve tumor if dx early enough.
If untreated is rapidly fatal.
Medulloblastoma
With total excision and radiation of a medulloblastoma, the 10 year survival rate is ___%.
only 50%
What is the chromosomal abberation seen in meningiomas?
Either deletion or mutation of chromosome 22
- Intracranial tumor
- Arises from arachnoid villi
- Produces sxs by compressing brain tissue
Meningioma
Peak incidence of meningiomas is which 2 decades of life?
- 4th (30 - 39 yrs)
- 5th (40 - 49 yrs)
Intracranial tumor most common in:
- parasagital areas
- convexities of cerebral hemispheres
- olfactory groove
- lateral wing of sphenoid
Meningioma
- Has propensity to erode contiguous bone
- Slightly more common in females (60:40)
- Benign tumor
Meningioma
- Majority arise sporadically
- Can be induced by cranial radiation w/ latent period of 10 - 15 yrs
- Well circumscribed, firm, bosselated masses of variable size
- Gray fibrous patter (when cut)
- Cause HA
Meningioma
- Meningiomas in which location cause anosmia?
- Meningiomas in which location lead to visual defects?
- Olfactory groove
- Suprasellar region
- Depending on location of tumor, pt usually has seizures rather than neuro deficits
- If not completely excised, tend to recur
- Doubles in size every 2 years
Meningioma
Pain down back/leg/knee when hip is flexed
Kernig’s Sign (sign of bacterial meningitis)
Spontaneous flexion of knees and hips when neck is flexed
Brudzinski sign (sign of bacterial meningitis)
