Pathoma Flashcards
What happens in severe global ischemia?
Results in diffuse necrosis - survival leads to vegetative state
How does dementia relate to Parkinson Disease?
Early-onset dementia (w/in 1 year of onset of Parkinson symptoms) is suggestive of Lewy Body Dementia, which is characterized by dementia, hallucinations and parkinsonian features. Histo reveals cortical Lewy Bodies.
What is vascular dementia?
Multifocal infarction and injury due to HTN, artherosclerosis, or vasculitis
What is an intracerebral hemorrhage?
Bleeding into brain parenchyma
Thrombotic strokes are due to and usually occur where?
Rupture of an antherosclerotic plaque and usually developes at branch points
Pale infarct at periphery
What are the clinical and radiological findings associated with epidural hematoma?
Lens-shaped lesion on CT
Lucid intervals may precede neuro signs
Herniation is lethal complication
What are the histological findings of Parkinsons?
Histology reveals loss of pigmented neurons in the substantia nigra and round, eosinophilic inclusions of alpha-synuclein (Lewy Bodies) in affected neurons.
Moderate global ischemia leads to?
Infarcts in watershed areas - damage to highly vulnerable areas
Pyramidal neurons of cerebral cortex - laminar necrosis
Pyramidal neurons of hippocampus - important in LTM
Purkinje layer of cerebellum - integrates sensory perception
The end result of the area affected by ischemic stroke?
Formation of fluid-filled cystic space surrounded by gliosis
What are the characteristics of Subacute Sclerosing Panencephalitis?
Progressive, debilitating encephalitis leading to death
Due to slowly progressive, persistent infection of the brain by the MEASELS VIRUS.
Infection during infancy and signs during childhood
Characterized by viral inclusions in neurons and oligodendrocytes
What type of necrosis results from ischemic stroke?
Liquefactive necrosis
What are the CSF findings associated with bacerial meningitis?
Neutrophils with decreased CSF glucose
Gram stain often identifies causitive organism
Embolic strokes are usually due to and involve what?
Emboli of the left side of heart (A fib)
Usually involves the middile cerebral artery
What is a berry aneurysm and what is the most common location?
Berry aneurysms are thin-walled saccular outpouchings that lack a media layer (increased risk of rupture)
Most commonly located in the anterior circle of Willis at branch points of the ACA
Associated with Marfan Syndrome
What are the molecular changes seen in AD?
Neuritic plaques made of amyloid
ABeta amyloid is derived from APP which is coded on chromosome 21 APP normally undergoes alpha cleavage, but when messed up it does beta - amyloid may also
Neurofibrillary tangles - intracellular aggregates of fibers composed of phosphorylated tau protein (microtubule associated protein)
Loss of cholinergic neurons
How is the diagnosis of MS made?
MRI reveals plaques
LP will show increased lymphocytes, increase Ig with oligoclonal IgG bands, and myelin basic protein
What are the characteristics of Progressive Multifocal Leukoencephalopathy?
JC Virus infection of oligodendrocytes (white matter)
Immunosuppression (AIDS) leads to reactivation of latent virus
Presents with rapidly progressive neuro signs
What are the major etiologies of global cerebral ischemia?
Low perfusion
Acute decrease in blood flow
Chronic hypoxia
Repeated episodes of hypoglycemia
What is Multiple Sclerosis and who does it present in?
Autoimmune destruction of the oligodendrocytes
Most common chronic CNS disease in young adults (20-30) more common in women
Associated with HLA-DR2 (HLA-DR15 accordine to Dr. Newell)
What is the pattern of change following an ischemic stroke?
Eosinophilic change in cytoplasm (RED NEURONS) - 12hrs after infarction
Necrosis (24hrs)
Infiltration of neutrophils (1-3 days)
Microglial cells (Days 4-7)
Gliosis (2-3 weeks)
What are the morphologic changes associated with AD?
Cerebral atrophy with narrowing of the gyri, widening of the sulci, and dilation of the ventricles (hydrocephalus ex vacuo)
Complications with Meningitis are usually seen with?
Bacterial meningitis
Death - caused by herniation secondary to cerebral edema
What is the classic cause of a subdural hematoma and what are the clinical and radiological signs?
Due to tearing of the bridging veins that lie between the dura and arachnoid arising from trauma
Crescent shaped lesion on CT
Presents with progressive neuro loss