CNS Path Quiz 6 part 3 Flashcards
loss of intellectual function to the degree that it interferes with ADL is termed
dementia
short term memory loss alone is not enough to be considered dementia
when might dementia be considered reversible? irreversible?
- reversible when caused by: infxn, drugs, alcohol, metabolic imbalances, hormone imbalances, depression
- irreversible when caused by: injury to the brain, disease
what is THE most common cause of dementia?
Alzheimer’s
most common form of Alzheimer’s disease?
late-onset Alzheimer’s disease
Early-onset Alzheimer’s disease associated with mutations in genes located on which chromosomes?
1, 14, and 21
Early-onset Alzheimer’s in half of all relatives before the age of 50 is another type of Alzheimer’s disease called?
Familial Alzheimer’s disease
what are the characteristic abnormalities found in the brains of individuals with Alzheimer’s disease?
- Amyloid plaques
- Neurofibrillary tangles
Neurofibrillary tangles are found inside of neurons and consist of insoluble twisted fibers made of what?
tau protein
macroscopic brain findings of a patient with Alzheimer’s disease
deepened sulci
diminished width of gyri
overall loss of mass
what type of dementia is characterized by micro-infarctions and areas of low blood flow causing damage to the brain?
vascular dementia (multi-infarct dementia)
macroscopic brain findings of a patient with multi-infarct dementia (vascular dementia)
multiple cystic infarcts in various locations
Cerebral atrophy seen in Pick’s disease (clinically similar to AD) occurs where?
frontal and temporal lobes
“knife-like” in appearance
Parkinson’s disease primarily affects which parts of the brain?
the pigmented neuronal groups (substantia nigra and locus ceruleus)
macroscopic brain findings of a patient with Parkinson’s disease
pale substantia nigra
Some patients with Parkinson’s disease also have dementia. What is this dementia called?
-Lewy body dementia
what’s the most common demyelinating disease?
Multiple sclerosis
pathophysiology of MS
- loss of myelin slows down nerve messaging
- plaques form over the affected area, further disrupting nerve communication
while there are no definitive diagnostic test for MS. what tests can be done and what are their findings?
- MRI w/ Gadolinium enhancement (can distinguish between old and new plaques)
- Lumbar puncture (elevated immune proteins)
Progressive multifocal leukoencephalopathy (PML) is due to infection by
the JC virus
it’s a demyelination disease
a brain bx of a patient with Progressive multifocal leukoencephalopathy (PML) reveals
enlarged astrocytes
Central pontine myelinolysis caused by
overly rapid correction for hyponatremia
In children, majority of tumors are found where?
below the tentorium (in the posterior fossa)
In adults, majority of tumors are found where?
above the tentorium
most common brain tumor in children is
astrocytic tumors such as glioblastomas
most common brain tumor in adults is
metastatic tumors
meningiomas are
- benign adult tumors
- arise in the arachnoid
gliomas are
- malignant tumors of glial cells
- occur in the cerebral hemisphere of adults
- occur in brain stem and cerebellum of kids
Astrocytoma appears how microscopically?
They can be stellate, spindle-shaped with fiber like processes, or plump with a large eosinophilic cytoplasmic mass
the most malignant form of astrocytoma? occurs?
- Glioblastoma multiforme (GBM)
- occurs in the frontal and temporal lobes
microscopic appearance of glioblastoma multiforme
high cellularity, cellular
anaplasia and nuclear anaplasia
Bifrontal butterfly S-shaped
lesion consistent with
glioblastoma multiforme
A butterfly lesion is a lesion which
infiltrates across the corpus callosum (allowing pathological process to spread from one hemisphere to another)
In cases of ependymomas found in the posterior fossa near the 4th ventricle, the development of what is common?
hydrocephalus
a ganglioma consists of
mature neurons
more often a neuronal tumor consists of mature neurons and glial cells called
ganglioglioma
The most common of the poorly differentiated brain tumors is the
medulloblastoma
microscopic appearance of medulloblastoma
individual tumor cells are small, ovoid or slightly elongated with high nuclear/cytoplasmic ratio
on MRI, a mass in the cerebellar is consistent with which neuronal tumor?
medulloblastoma
