MC brain tumor in adults
METS
What are red neurons?
dying neurons dt sustained hypoxia
- vacuolated
- eosinophilia of cytoplasm
Red Neurons are seen in what dz?
cerebral infarction aka stroke
MC cause of thrombotic occlusion in the brain? (this causes an ischemic stroke)
atherosclerosis
- of course, smoking is a risk factor
What is the most malignant form of astrocytoma?
GBM, Glioblastoma Multiforme
- this is the worst dx of primary brain tumors
Glioblastoma Histo
high cellularity, anaplasia, nuclear anaplasia…. increase in mitotic figures
What brain lesion looks like a butterfly (S-shaped) that crosses the corpus
Glioblastoma Multiforme
After 12-24 hrs of a stroke (cerebral infarct), what will the brain look like, grossly?
- “blurring of grey-white junction”
- also, discoloration, softening, edema
MC brain tumor in children?
astrocytic tumors
- Glioblastoma!
- then, medulloblastoma, ependymoma, craniopharyngioma
4 major classes of primary brain tumors:
- meningioma
- glioma
- neuronal
- poorly differentiated
what are some gliomas?
astrocytoma, oligodendroglioma, ependymoma
Ependymomas are usually located where?
- line the ventricles! of the brain
- but after 20 yo, more often found in spinal cord
MC vessel affected in cerebral vascular stroke? (like thrombotic occlusion in ischemic stroke)
middle cerebral artery
- (this vessel comes off the carotid)
Which is worse? Ischemic or Hemorrhagic stroke?
hemorrhagic (specifically intracerebral), but less common
What is a berry aneurysm?
thin wall out-pouching in the circle of Willis
Most common cause of subarachnoid hemorrhage?
rupture of a berry aneurysm
- remember that med student w the acute severe HA, then died
MC type of vascular malformation in the brain that is clinically significant?
Arteriovenous malformations
what type of hematoma of head usu dt trauma - blood from middle meningeal artery accumulates bet dura and skull
Epidural Hematoma
What type of hematoma in the head occurs when bridging veins between the brain and superior sagittal sinus are damaged and usually occurs in the fronto-parietal region of the cerebrum?
sub-dural hematoma
- bet dura and arachnoid
- crescent shaped
What types of hemorrhage do arteriovenous malformations cause?
intracerebral or subarachnoid
MC cause of intracerebral hemorrhage?
HTN
vs. trauma
Which brain tumor is the most common of the poorly differentiated (looks embryonal), usu in cerebellum, and 20% of all brain tumors of children?
Medulloblastoma
tumor cells are small, ovoid, slightly elongated w high nuclear/cytoplasmic ratio
Medulloblastoma
What the usually causes of cerebral infarction dt ischemia and hemorrhage?
- ischemic stroke is usu dt atherosclerosis
- hemorrhagic stroke is usu dt HTN
Which is MC? ischemic stroke or hemorrhagic stroke?
ischemic stroke
if you’re suspicious of a stroke, what imaging to do?
CT first (blood is opaque), then MRI
What is Central Pontine Myelinolysis?
usu iatrogenic - overly rapid correction of hyponatremia - demyelinating dz
Cerebellar and brainstem stroke are usu dt problems with what arteries?
vertebral and basilar
What is Hypertensive Encephalopathy?
Acute rise in BP causing an increase in intracranial pressure –> HA, confusion, V, convulsions, coma, death
In children, 70% of brain tumors are located ____ the tentorium whereas in adults, 70% are found _____ the tentorium.
- below
- above
What is a Basal skull fracture?
a type of linear skull fracture - petrus portion of temporal bone - leaks spinal fluid from ear
MC skull fracture
Linear - dt severe head injury
you will see Raccoon’s eyes and/or Battle’s sign in what kind of skull fracture?
Basilar skull fracture
Battle’s sign - mastoid ecchymosis
Epidural Hematoma assoc w damage to what artery?
MMA, Middle Meningeal Artery
MC cause of Dementia
Alzheimer’s Dz
- death of nerve cells in brain
- MC form is late-onset (>65 yo)
Alzheimer’s Dz, the MC cause of Dementia, is associated with what characteristic abN found in the brain?
Amyloid plaques (OUTSIDE) and Neurofibrillary tangles (INSIDE)
MC form of Alzheimer’s Dz
late-onset (vs early, familial)
Vascular Dementia is also known as?
Multi-infarct Dementia, MID —> low blood flow leading to damaged cells and loss of neuronal fx - cystic infarcts
Vascular Dementia or MID imaging shows?
- cystic infarcts
- increased ventricular size
- diminished vol of grey and white matter
What is Pick’s Dz?
uncommon dementia affecting frontal and temporal lobes
atrophy of brain looks “knife-like” is characteristic of what kind of dementia?
Pick’s Dz
What lobes are affected in Pick’s Dz?
frontal, temporal
What areas of the brain are affected in Parkinson’s Dz?
pigmented
- substantia nigra, locus ceruleus
Lewy Bodies are associated with?
Parkinson’s with dementia
- found within cytoplasm of neurons in the brain
- a ddx for Alzheimer’s
What is the MC demyelinating Dz?
Multiple Sclerosis
dt infx by JC virus?
Progressive Multifocal Leukoencephalopathy, PML, a demyelinating dz
Are meningiomas usu malignant or benign?
- benign
- adults
- in arachnoid, attached to dura
Are Gliomas usu malignant or benign?
they are malignant
- MC primary tumor the brain (astrocytoma)
What is a TIA?
Transient Ischemic Attack
- preceding an ischemic stroke dt complete occlusion of a cerebral vessel, TIA’s or transient neurologic sxs are clinical markers for an increased risk of cerebral infarction
What is the 3rd leading cause of death in the US?
stroke
- also the 3rd leading cause of major disability
What is Gliosis?
reactive proliferation of astrocytes in response to damage of the CNS —> can lead to a glial scar
Macroscopic view of brain after cerebral infarct?
diffuse edema, narrowed sulci, widened gyri
When will you see vacuolated neurons and eosinophilia of neuronal cytoplasm dt cerebral infarction?
first 12-24hrs after infarct
When will you see infiltration of a cerebral infarct by neutrophils at edges of the lesion?
after ~24hrs
When will you see increased # of m0 following a cerebral infarct?
1-14d
