Part 2 Flashcards
Which cells of CNS are most vulnerable to injury?
-pyramidal cells of hippocampus, Sommer Sector (CA1), Purkinjee cells of cerebellum
Reactive cell in CNS that proliferates
astrocytes
“Fried egg” appearance–which cell type?
oligodendrocytes
Pyknotic and rectangular–which cell type?
microglial
What are the inflammatory cells of the CNS?
Trick question! There are NO inflammatory cells in CNS
What are Purkinjee cells found? What are they?
Major motor neurons found between the granule layer and molecular layer of cerebellar cortex
Homunculus–Face, LE, Mouth/tongue, UE
Face–lot of sensory and motorLE–LITTLE sensory/motorMouth–lots of sensory/motorUE=More sensory and motor compared to LE
What is gliosis
astrocytic proliferation
Acute injury changes
central chromatolysis (clearing), spheroidal, red neurons
What are axonal spheroids? When are they seen?
aka diffuse axonal injury–When axons are transected, they tend to roll up/ball up Seen POSTTRAUMATICALLY and in DIFFUSE injury to the brain like blunt force trauma
What is Lipofuscin? Where is it found?
Yellowish brownish pigment related to aging and found in NEURON CELL BODY
Bubbly vacuolization of astrocytes is called?
gemistocytic astrocyte
Which astrocytes have a spindle cell configuration?
Fibrillary astrocytes
Corpora amylacea
Calcium concretions seen in arachnoid granulations (like brain sand–is gritty)
Can you see lymphatic inflammatory response in CNS?
NO! only see gliosis
Astrocytes cover _____
inner surface of pia mater and every blood vessel of CNS
Cells in CNS associated with wound healing? How? Are there fibroblasts in CNS?
Astrocytes via gliosis NO fibroblasts in CNS so no scar formation in CNS–see gliosis instead and get cavitary lesion instead
What are Rosenthal fibers? When do you see them in the CNS?
Chronic reactive astrogliosis; brightly eiosinophilic and hylanized (waxy appearance under microscope); elongated/rectangular cells; seen in hemartomas of posterior fossa
Which cells are affected in PML? Which cells are affected in CMV?
Oligodendrocytes in PML (demyelination)Ependymal cells in CMV
What does oligodendrocytes look like when there is hypoxia?
Perinuclear halos; fried egg appearance
What does an ependymal cell look like?
can be flattened/cuboidal or can have cilia/microvilliPlicae on ependyma does NOT mean neoplasm!
Normal Adult vs. child ependymal cells
Adult: obliterated with residual rests and rosettes of ependymal cellsChild: ciliated cuboidal ependymal cells
Which type of lesions (primary or metastatic) generate more edema in the CNS?
Primary
Cytotoxic edema is intercellular or intracellular?
Intracellular
Meningitis causes what kind of hydrocephalus–communicating or non-communicating?
CommunicatingNO lumbar tap if ICP is high–brain can herniate!!
Increased ICP is usually due to?
Usually due to Hemorrhage or ischemia but may be due to tumor sometimes
S/S of raised intracranial pressure
Headache, impaired upward gaze, CN VI palsy, seizures, papilledema, ataxia
Taenia solium (pig tapeworm) causes what and what geographic region do you see it in?
Cystercircosis–see in Latin AmericaNon-communicating hydrocephalus
What is kernohans notch?
compression of cerebral peduncle on left against tentorium cerebelli due to transtentorial herniation results in IPSILATERAL hemiparesis/ hemiplegia (on the side of herniation)
Herniation through foramen magnum affects which vascular structures? What level is the formamen magnum at?
Foramen magnum is at the level of the superior cerebellar peduncle which means vital structures like the basilar artery and vertebral artery are affected (duret hemorrhage??)
How can you use the pineal gland as a marker for midline structures?
As we age, there is normal calcifications of the pineal gland which can be used to access midline
Cerebral palsymost common insult?
Non progressive neurologic motor defects characterized by spasticity, dystonia, ataxia/athetosis and paresis attributable to insults during prenatal/perinatal period Most common insult is ischemia during vaginal birth
Diseases/disorders associated with perinatal brain injury
Cerebral palsy, intraparencymal hemorrhage, periventricular leukomalacia, ulegyria, multicystic encephalopathy
Multicystic encephalopathy morphology?
-Diffuse, ischemic injury with cystic formations in brain–dont survive
Germinal matrix vessels form around ventricles but in normal people they become atretic. In children sometimes these vessles can hemorrhage–this is called?
Periventricular leukomalacia
Neural tube inner vs outer part
inner=ventricular systemoutside=brain and spinal cord
Cerebral cortex and posterior fossa absent
Anencephaly
Protrusion of brain through defect in neural tube
Enencephalocele
Difference between Arnold Chiari and Dandy Walker
Arnold Chiari=SMALL posterior fossa so cerebellum goes into foramen magnumDandy Walker= LARGE posterior fossa so cerebellum wings out because its not constrained so compromises CSF drainage through Foramen of Luschka and Magende; absense of cerebellar vermis, dysplasias of brainstem nuclei
Dandy Walker malformation is associated with what symptoms and what abnormalities of organs?
Hyperkinetic movement disorder (jerky movement of voluntary muscles–lacks control)Associated with HEART malformations as well as face and limb abnormalities
Fluid associated anomalies
Syringomyelia and hydromyelia
Epidural vs. Subdural Hematomas in terms of margins, shape on CT, cause
Both associated with traumaEpidural has smooth margin, subdural has irregular margin because hits sulciSubdural has membrane formation due to fibroblast proliferation in meninges so can contain itselfEpidural associated with lucid interval but subdural can have it too
Post-traumatic hydrocephalus is a ____ process
astrogliotic
Which kind of stroke (embolic or thrombotic) is associated with hemorrhage?
Embolic
Most common etiology of embolic stroke?
from heart mural thrombi (arteriosclerosis with mural thrombus in heart–portion of it breaks off, travels to brain and causes stroke)
Global ischemia is caused by and affects? Laterality?
Blood loss/asphyxiation and affects both hemispheresleads to death or vegetative state if not transient
Local ischemia laterality
UNILATERAL
MCA blood supply to?
face, throat, upper extremities (contralateral) and areas for speech, temporal areas, parietal, and frontal lobe, BASAL GANGLIA
Which arteries are most vulnerable to general ischemic events like blood loss or asphixiation?
ACA and MCA
Area most commonly affected in stroke?
Horizontal M1 segment and lenticulostriate vessels
What kind of stroke is more common–Embolic or thrombotic?
Embolic
Left MCA syndrome
Language loss (aphasia), right hemiparesis, right hemisensory loss, right visual field deficit, left gaze preference (preference toward side of stroke)
Periventricular calcifications, microcephaly, brain damage in utero; also common in HIV patients; subacute encephalitis; what disease?
CMV
Characteristic morphology of CMV
LARGE INTRANUCLEAR inclusions; also see cytoplasmic inclusions
What part of brain does Rabies affec and what is the morphologyt? CMV?
Rabies affects brainstem distribution with perivascular inflammation while CMV affects periventricular areas
Rabies symptoms
ascends along peripheral nerves; parasthesias at wound site, hydrophobia (foaming at mouth), flaccid paralysis, respiratory failure
HIV encephalopathy morphology
chronic inflammation, microglial nodules, MULTINUCLEATED GIANT CELLS, reactive gliosis, myelin pallor
When do you see HIV dementia
associated with quantity of microglial cells–higher quantity
Disease susceptibility associated with HIV
CNS lymphoma (Karposi sarcoma), infiltrating squamous cell carcinoma of the cervix (from HPV)
PML associated with what virus? Do you see it in everyone with the virus?
JV polyomavirus–everyone has it but PML only affects people with the virus who are immunocompromised
Candida causes ____ when disseminatedMucor and aspergillus are ____ fungi
microabcesses (yeast form in body)angioinvasive–causes vasculitis; mucor–invades sinus walls (hyphae form in body)
Geography: Histoplasmosis, blastomyces, coccidoides
Histo and Blasto in midwestBlasto–southwest
Naeglaria amoeba affects what part of CNS?
inferior basal frontal lobe–access through cribiform plate
cerebral toxoplasmosis morphology
calcifications, brain abcess near gray white junctions and deep gray nuclei; abcess is NOT necrotizing but is circumscribed and well loculated
Arbovirus (eg. Easter Equine encephalitis) symptoms
Fever, headache, nausea, malaise, confusion
mosquito types for the followingZika, west nile, yellow fever, dengue, chikin guna; where found?
Zika–aides West nile–aides and coolixyellow fever, dengue and chikin guna= aidesAides found in florida and southern louisina
What does prion diseases do in the CNS? (which cells affected)
causes neuron loss
What areas does Multiple sclerosis affect? Morphology of MS?
PERIVENTRICULAR; multiple well circumscribed, somewhat depressed, glassy, gray/tan irregularly shaped plaques; commonly occur adjacent to LATERAL VENTRICLES;
Which cells are involved in destroying myelin in MS?
T-cell mediated–Th17 and TH1see T cells and macrophages
CSF in MS
increased protein, some pleocytosis maybe, increased IgG, (oligoclonal bands) from B cell activation, MYELIN BASIC PROTEIN
Neuromyelitis optica (NMO) aka Devic disease–mechanism; S/S
Humoral autoimmune mechanism against anti-aquaporin 4BILATERAL optic neuritis (MS is usually unilateral); SC demyelination, more common in women
MS vs. ADEM (Acute demyelinating encephomyelitis) and ANHE (acute necrotizing hemorrhagic encephalomyelitis) vs CPM
MS is POLYPHASIC (lesions are different ages); ADEM and ANHE are MONOPHASIC (same age) ADEM follows a viral URI or antivral immunization (headache, lethargy, disorientation, coma; 20% mortality)ANHE is FATAL and ALWAYS preceded by URICPM–correction of hyponatremia, NON immunologic; quadroplegia seen
