Neuropathology (1-3) Flashcards
name the part(s) of the brain
telencephalon
cerebral hemispheres
name the part(s) of the brain
diencephalon
thalamus and hypothalamus
name the part(s) of the brain
mesencephalon
midbrain
name the part(s) of the brain
metencephalon
cerebellum and pons
name the part(s) of the brain
myelencephalon
medulla
name the term
degeneration following normal development
abiotrophy
name the term
swollen astrocytes in response to metabolic encephalopathy
Alzheimer Type 2 Cells
name the term
glial cell, the fibrocyte of the brain but very busy
astrocyte
name the term
astrocytes have undergone hypertrophy (increased size, enlarged nucleus visible)
astrocytosis
name the term
astrocytes have undergone hyperplasia, increased number
astrogliosis
name the term
dispersal and loss of cytoplasmic Nissl substance
chromatolysis
name the term
primary if selective loss/destruction of myelin rather than secondary to general inflammation
demyelination
name the term
developmental defects of the neural tube in which there is failure to calesce and close
dysraphia
name the prefix
relates to the brain
encephalo-
name the term
specific form of hypertrophic astrocyte with visible cytoplasm
Gemistocyte
name the term
increased numbers of glial cells (any, there are then specific terms for each type of cell)
gliosis
name the term
transplacental destruction with massive bilateral necrosis of the cortext leaving only fluid filled sacs
hydranencephaly
name the term
accumulation of fluid in the brain
hydrocephalus
name the term
pia and arachnoid layers (closest to the brain)
leptomeninges
name the prefix
relates to white matter in the brain
Leuko-
name the term
lack of gyri and sulci;
abnormality in most species but normal in some (mouse, rat, rabbit, bird)
lissencephaly
name the term
oligodendrocytes and astrocytes
macroglia
name the term
softening;
gross change caused by necrosis
malacia
name the term
the macrophages of the CNS, derived from monocytes
microglia
name the term
comprises layers of oligodendrocyte cell membranes wrapped around axons to protect them and speed up conduction along the axon
myelin
name the term
inflammation of the spinal cord
Myelitis
name the term
eating of neurones’ by phagocytes; some viruses induce this
neuronophagia
name the term
clumps of rough ER; means the cell is making a lot of protein
Nissl
name the term
glial cell, produces the myelin to insulate the axons; CNS only
oligodendrocyte
name the term
dura matter
pachymeninges
name the prefix
relates to grey matter
polio-
name the term
inflammation of multiple spinal or cranial nerve roots
polyradiculoneuritis
name the term
transplacental destruction with usually a single, fluid filled cavity in the cerebrum
porencephaly
name the term
the equivalent of teh oligodendrocyte in the PNS
Schwann cell
name the term
degeneration of an axon distal to the site of injury
Wallerian degeneration
name the 5 main cell types in the CNS
- oligodendrocytes
- astrocytes
- microglial cells
- choroid plexus epithelial cells
- ependymal cells
name 4 reasons why neurons are especially vulnerable to injury
- A high metabolic rate
- dependent axon
- Little stored energy
- No capacity to regenerate
name 4 main ways neurons respond to injury
- acute necrosis
- chromatolysis
- Wallerian degeneration
- vacuolation
name the neuron response to injury
This is a form of acute necrosis that occurs in a distinct pattern, due to selective destruction of neurons in the deeper layers of the cerebral cortex
laminar cortical necrosis
name 2 main instances where laminar cortical necrosis occurs in cerebral cortex
- thiamine deficiency
- salt poisoning/water deprivation
name the neuron response to injury
NOT necrosis; adaptive response to deal with injury BUT can LEAD to necrosis;
cell body swells and the Nissl substance disperses allowing the cell body to produce proteins for rebuilding
chromatolysis
name the neuron response to injury
this is breakdown of an axon and its myelin sheath distal to the point of injury;
classical cause is axonal transection
Wallerian degeneration
name the neuron response to injury
this is the hallmark of transmissible spongiform encephalopathies (BSE, scrapie)
neuronal vacuolation
list the CNS cells in order from MOST to LEAST susceptible to injury
nerons > oligos > astrocytes > microglia > blood vessels
name the 3 main types of cerebral oedema
- cytotoxic
- vasogenic
- hydrostatic (interstitial)
name the type of cerebral oedema
caused by altered cellular metabolism (energy deficit so can’t pump out Na+ and water)
eg. hypoxia, toxins
cytotoxic
name the type of cerebral oedema
caused by vascular injury and breakdown of BBB;
most common form in animals
vasogenic
name the type of cerebral oedema
caused by increased ventricular hydrostatic pressure (ie. hydrocephalus)
hydrostatic (interstitial)
what is the outcome of cytotoxic cerebral oedema?
intracellular accumulation of fluid
what is the outcome of vasogenic cerebral oedema?
extracellular accumulation of fluid
(white matter typically affected)
what is the outcome of hydrostatic (interstitial) cerebral oedema?
extracellular accumulation of fluid
(periventricular)
name 4 consequences of ischemia
(neuropathology)
- acute neuronal necrosis
- infarct
- malacia
- vasogenic oedema
this is the necrosis of tissue following obstruction of its blood supply
infarct
name 4 causes of infarcts in the CNS
- thrombosis
- embolism
- FCEM (fibrocartilaginous embolic myelopathy)
- vasculitis
name 5 routes of entry for bacteria, fungi, protozoa, and viruses to invade the CNS and produce an inflammatory response
- hematogenous
- direct implantation
- peripheral nerves
- local extension
- infiltrating macrophages harboring organisms
name 4 locations in the CNS where inflammation can become established
- epidural space
- subdural space
- leptomeninges
- brain
name the type of infection associated with fibrinous exudate (leptomeningitis / encephalitis)
bacteria (inc. Mycoplasma)
name the type of infection associated with suppurative exudate (leptomeningitis / encephalitis)
bacteria & fungi
name the type of infection associated with lymphoplasmacytic exudate (leptomeningitis / encephalitis)
viruses
name the type of infection associated with granulomatous exudate (leptomeningitis / encephalitis)
bacteria or fungi
name the type of infection associated with hemorrhagic exudate (leptomeningitis / encephalitis)
speticemia or infarcts
name the inflamation presentation in the. CNS
typically caused by bacteria that spread to the meninges in the bloodstream;
brain swells and meninges are opaque but there may be NO gross lesions;
neutrophils predominate
suppurative leptomeningitis
name the presentation of inflamation in the CNS
result of bacterial infections and manifests as abscesses;
may be single or multiple, vary in size with a central, liquefied cavity
suppuratice encephalitis
name the subcategory of suppurative encephalitis
Bacteria gain entry via oral mucosa → trigeminal nerve → trigeminal ganglion in brain;
CNS form mainly occurs in ruminants eating silage, especially where pH is too high;
Usually NO GROSS LESIONS;
Microabscesses AND lymphoplasmacytic cuffing of vessels;
Clinically: Circling, unilateral facial nerve paralysis, drooling, recumbency, paddling
DEATH
Listeriosis
name the presentation of inflamation in the CNS
due to viral infection (and some protozoal infections);
meninges and brain are affected;
no gross lesions but common hallmark of lesions of CNS viral infections are neuronal necrosis, gliosis and perivascular lymphoplasmacytic cuffing
lymphocytic / lymphoplasmacytic meningoencephalitis
name the presentation of inflamation in the CNS
NOT usually due to infection;
eosinophils predominate;
most likely cuases are salt poisoning and/or water deprivation
eosinophilic meningoencephalitis
this is a temporary loss of consciousness following head trauma; full recovery is usual but if repeated or severe → neuronal loss and haemorrhage, even death
concussion
this is a focal haemorrhage as direct result of trauma
contusion
this is the tearing of CNS by bone within the skull or by penetrating objects;
most severe and most serious form of traumatic injury as it carries additional risk of contamination/infection
laceration
name 4 locations hemorrhagic can occur in the CNS
- epidural
- subdural
- leptomeningeal
- cerebral
name 5 causes of spinal cord compression
- abscess
- fracture
- neoplasia
- intervertebral disk disease
- malformations
name 4 types of hydrocephalus
- internal
- external
- communicating
- hydrocephalus ex vacuo
what is the location of fluid with internal hydrocephalus
within the ventricles
what is the location of fluid with external hydrocephalus
within arachnoid space
what is the location of fluid with communicating hydrocephalus
within ventricles AND arachnoid space
name the primary CNS neoplasm
Most frequent primary CNS tumour in cats and dogs;
Originates in the meninges;
Acts as a compressive, space-occupying lesion which seldom invades
meningioma
name the primary CNS neoplasm
Third most common primary CNS tumour in dogs;
Predilection for brachycephalic breeds;
Solid, firm, grey-white; sometimes mottled red with areas of necrosis/haemorrhage
astrocytoma
(glioma)
name the primary CNS neoplasm
Second to meningiomas in dogs; predilection for brachycephalic breeds; Soft, grey to pink/red and often gelatinous
oligodendroglioma
(glioma)
name the primary CNS neoplasm
occurs mainly in ventricles;
may spread in the ventricular system via CSF;
expansile but can be invasive and destructive
ependymoma
name 3 common primary neoplasms of the CNS
- meningioma
- glioma
- ependymoma
this is a brain disorder manifested as a paroxysmal cerebral dysrhythmia;
Sudden onset, ceases spontaneously but tends to recur
seizure
name 4 reasons peripheral nerves can be predisposed to traumatic injury
- superficial location
- proximity to bone
- dystocia
- proximity to injection sites
name the degenerative disease
Idiopathic degeneration of left recurrent laryngeal nerve → atrophy of the left dorsal cricoarytenoid muscle → inability to abduct arytenoid cartilage and vocal fold → airways partially obstructed on inspiration
Equine laryngeal hemiplegia (‘roarers’)
can neurons regenerate?
NO
can axons in the PNS regenerate?
YES
