Card Set Information
Where does coup, contracoup injury occur?
On site of impact, usually convex brain
Opposite side (against skull), more severe.
What are the patterns of skull fracture?
: large fracture with multiple fragments
: Opens or reaches suture.
What is a concussion, what function is most often affected?
Traumatically induced alterarion in mental status (+/- loss of conciousness)
What is a contusion?
Bruise, usually on crest of gyri
Often found in temporal or frontal lobes.
Where is, what causes an epidural hemorrhage?
Between dura and calvarium
Rupture of meningeal (often middle meningeal) arteries due to trauma.
What causes a subdural hematoma?
Rupture of bridging veins
Acceleration/deceleration injury (eg. shaken baby syndrome)
: nausea, vomiting, dizziness, sleepiness.
Subarachnoid hemorrhages may be caused by?
Rupture of berry aneurysm
Rupture of leptomeningeal blood vessels
What causes diffuse axonal lesions?
Acceleration/deceleration result in axonal damage due to shearing stress.
What is the time course of diffuse axonal injury?
: accumulation of Amyloid Precursor Protein (APP)
: Axonal bulbs/varicosities on H&E
: Axonal spherules (with ubiquitin, APP, NF+)
What is the hallmark lesion of MS, what does it represent?
Area of demyelination
Often found in:
-periventricular white matter
-subcortical white matter
-cerebral cortex and gray matter
What stains are used for myelin?
Luxol Fast Blue: lack of staining identifies myelin loss.
What other cells may be found in active plaques, how can you stain for them?
Macrophages- parenchymal and perivascular with myelin debris
Lipid containing macrophages
Name three pathological processes in MS?
: lymphotoxin, TNFa, IL-6
: upregulation of ICAM-1 and VCAM-1.
What are the three types of cortical lesions in MS?
Gray/white matter junction
: No B or T lymphocytes
Cortex abutting the pia
: Microglial activation prominent.
What do shadow plaques represent?
Incomplete process early in MS.
What is the Marburg type of MS?
Fulminant of rapid course
Children and young adults
large conluent areas of demyelination
Massive macrophage infiltration
What is tumefactive MS?
Acute inflammatory demyelinating mass presenting as a neoplasm.
What is Devic's disease?
: optic neuritis + acute transverse myelitis
: Aquaforin 4 + Ig perivascular deposition.
What is acute dissmeinated encephalomyelitis (ADEM)?
Acute, monophasic (demyelinating)
may follow infections
Affects white matter more.
What causes subacute sclerosing pan encephalitis (SSPE)?
Infection of oligodendrocytes by defective measles virus.
What is the clinical disease and pathology of SSPE?
Global loss of higher brain functions and death
Perivascular lymphoid infiltrate
Intranuclear inclusions of measles virus.
What causes central pontine myelinolysis?
Rapid correction of hyponatremia.
What can cause toxic leukoencephalopathy?
A number of drugs, prescription and recreational.
Thymic hyperplasia or thymoma may be found in what NMJ condition?
Women affected twice as often as men.
Is MG acquired or congenital?
Acquired, autoimmune, humoral
Anti-AchR antibodies bind to alpha subunit.
What is Lambert Eaton Myasthenic Syndrome (LEMS) associated with?
Small cell lung carcinoma - paraneoplastic syndrome (60%)
Men twice as much as women.
What is the pathology of LEMS?
Decreased pre-synaptic release of Ach
Antibodies against presynaptic voltage gated Ca2+ channel.
What are the clinical presentations of muscle strength in MG and LEMS?
: decreased strength throughout the day, increased with rest
: Increased strength with more contractions.
What are leukodystrophies?
Inherited demyelinating diseases in which the clincial sympoms derive from abnormal myelin synthesis or turnover
Mostly Autosomal Recessive, some X-linked.