CNS Flashcards
The thalamus and hypothalamus make up the ________
Diencephalon
The midbrain with the pens, medulla, cerebellum, and medulla oblongata is AKA
Mesencephalon
In a PM exam, the Brian should be immersed in formalin for ____days
5-7
What cells make up the BBB
Astrocytes and endothelial cells
What are the neuroglial cells?
Macrolia - astrocytes and oligodendrocytes
Microglial
Ependymal
What cells provide support and the myelin sheath to the axons within the CNS
Oligodendrocytes
Can provide myelin for several axons at once
What is the function of microglia?
Immunosurveillance
Immunoregulation
Reparative (phagocytic)
_________ cells are microglial cells that are globular and swollen after having phagocytozed debris from injured cells
Glitter
What do you call the breakdown of cytoplasmic Nissil bodies
Chromatolysis
Indicates neuronal cell injury
What are nissil bodies?
Aggregates of RER and free polyribosomes
Neurons are shrunken and exhibit cytoplasmic eosinophilia, nuclear pyknosis, or karyolysis. These changes are due to?
Ischemic cell change
Histopathology shows an accumulation of glial cells around a shrunken neuron. What is this?
Satellitosis/Neuronophagia
Microglial cells are phagocytic–> advanced degeneration
Vacuolation within the neuropile?
Spongiform change
Hepatic encephalopathy can cause what change in the brain
Status spongiosus (spongiform change)
Accumulation of glial cells around a blood vessels is called?
Perivascular cuffing
Reactive astrocytes AKA ?
Gemistocytic
In the brain of a dog you see spongiosis, perivascular cuffing, and inclusion bodies within the astrocytes. What disease is this due to?
Canine distemper
What is Wallerian type degeneration
Due to sectioning of the axon. Degeneration distal to site of injury. Will cause muscle atrophy
Can regenerate in many cases
Toxins and viruses can cause demyelination damage. What is the main consequence
Slow nerve conduction
No muscle atrophy
If the neuronal cell is injured, what kind of degeneration will occur?
Axonal degeneration
No maintenance of axon health
Muscle atrophy
Teratogens, with the exception of viruses, act mainly during the __________ of pregnancy
First 1/3 (during organogenesis)
Proencephalic hypoplasia is AKA
Microencephaly
Microencephaly can result due to ________ infection in calves and ________ infection in swine
BVD; classical swine fever
Both pestiviruses
An increase in CSF is called
Hydrocephalus
What is the difference between compensatory and obstructive hydrocephalus?
Compensatory-> CSF increase to take up space where parenchyma has been destroyed
Obstructive-> aqueductal atresia or stenosis (mesencephalic aqueduct)
Common manifestations of hydrocephalus in puppies?
Depression Dementia Seizures Blindness Exopthalmos Ventrolateral strabismus
Porencephaly
What dis/
Formation of small fluid filled cavities in the brain
Hydranencephaly
What dis
Formation of large fluid filled cavities i the brain
Hydranencephaly and porencephaly usually occur in utero with cavitations resulting form ??
Destruction of immature neuroblasts
Vascular injury
How are hydrancephaly and porencephaly different from hydrocephalus?
Hydranencephaly/porencephaly => CSF accumulates in lateral ventricles and cavities parenchyma, no malformation of the cranium
Hydrocephalus => accumulation in the ventricles or arachnoid space causing malformation of the cranium
In utero infection of cats by ______________ can cause cerebellum hypoplasia
Feline panlukopenia virus
Baby kitten mitten..
Symmetric ataxia
Hypermetric base-wide gate
Truncal ataxia
Intention tremor
Cerebellar hypoplasia
What do you call defective closure of the bony encasement of the spinal cord?
Spina bifida
T/F: most lysosomal disease are progressive and genetically determined
True
Few can be acquired through neurotoxic substances that inhibit specific lysosomal activities
Histopathology
Enlarged, vacuolated, foamy cytoplasm around the neuron
This is typical of what diseases?
Lysosomal storage disease
Eg Gangliosidosis Globoid cell leukodystophy A and B mannosidosis Mucopolysaccharidosis Ceroid- lipofuscinosis Niemann -pick disease
What gross change in the brain of a sheep is caused by ceroid lipofuscinosis ?
Cerebrocortical atrophy
Cow that was born normally develops the following neurological signs
Ataxia
Lateral recumbancy
Visually deficient
PM - enlarged cerebellum
Histo- small vacuoles in cytoplasm around perkinje cells
Mannosidosis
Ingestion of __________ can cause an acquired form of mannosidosis
Locoweeds
–> contain potent inhibitors of alpha-mannosidase
What is the significance of cerebral edema ?
Life threatening
Increased ICP -> compression ischemia (hypoxia), edema, and necrosis
PM of brain Wet, soggy Swollen Flatten gyri Soft
Cerebral edema
Cerebellar coning in the cat can result due to?
Cerebellar edema
What is coup and counter coups lesions, with regards to brain injury?
Coup - Initial impact
Countercoup- when brain strikes the inside of the skull
What lesion can be see in horses that fall backwards
Basilar fracture
Neurofibrillary tangles are a common finding in dementia but can also be a result of?
Chronic traumatic encephalopathy (boxers encephalopathy)
They are fibrillation intracytoplasmic inclusion in neurons ->swelling of neurons
What are locations of hemorrhage int he brain?
Extradermal hematoma
Subdural
Subarachnoid
Parenchyma (white or grey matter)
Extradermal hematoma are due to rupture of the ___________ artery
Meningial
What are causes of polioencephalomalacia?
Thiamine deficiency Sulfur toxicity (high concentration in water or accumulation in plants) Salt poisoning/water deprivation
What do you call a marked dorsal extension of the head and neck accompanied by rigid extension of the limbs?
Opisthotonus
Due to thiamine-responsive qpolioencephalomalacia
Lamb PM
Yellowish discorlouration in the cerebral cortex close to the longitudinal fissure
Polioencephalomalacia
What disease is associated with autofluorescence under UV light
Polioencephalomalacia due to thiamine deficiency
It’s winter time on the pig farm..
all the pigs are quiet.. something is wrong..
PM cerebral cortex
- spongiform change
- shrunken neurons with eosinophilic cytoplasm and dark pyknotic nuclei
- prominent blood vessels with perivascular eosinophilic infiltration
Salt poisoning/ water deprivation
T/F: thiamine deficiency is reported in cat, dog, and wild carnivores
Truths - called chastek paralysis
Diets containing fish have high thiaminase levels which destroys thiamine
Cooked meats are also thiamine deficient
Lesions due to Chasteks paralysis are localized where?
Brain stem and hippocampus
> hemorrhage and necrosis of caudal canaliculi
Unlike in rumaints that is on the cerebral cortex
What toxin primarily will effect the basal ganglion producing endothelial damage, ischemic necrosis, gliosis, and cavitation?
Clostridum perfringens type D - Epsilon toxin
Corn can be contaminated by _______________ fungus which will cause CNS lesions leading to ataxia, dementia, and head pressing.
Fusarium verticilloides and/or Fusarum proliferatum (Fumonisin B1)
What is the MDx associated with moldy corn toxicity?
Leukoencephalomalacia
Yellow star thistle can cause what disease in horse?
Nigropallidal encephalomalacia (chewing disease)
Dysfunction of muscles of mastication and deglutination (CN V, VII, and XII)
glutathione depletion –> oxidative damage and mitochondrial dysfunction and neuronal cell death
Horse
Idle drowsiness
Unable to grasp food or drink water
Purposeless chewing motion
PM shows bilateral liquefactive necrosis in the globes pallidus
Nigropallidal encephalomalacia
Yellow star thistle
Knapweed
A suppurative meningitis is would have what etilogy
Bacterial infeciton
In a pig..
Supperative meningitis
With hyperemia
Cellular debris accumulation in the ventricles and choroid plexus
MDx and EDX?
Meningitis-encephalitis and ependymitits
Streptococcus suis
Feedlot cattle
Fibrinolysis-suppurative, hemorrhagic and necrotizing meningoencephalitis
EDX?
Histophilus somni Thrombotic meningioencephalitis (TME)
You feed your sheep and cattle some new silage..
They develop circling, head tilt, facial paralysis, drooling saliva, and death
EDX?
Listeriosis (Circling disease)
Ingestion -> retrograde travel to brainstem via trigeminal nerve
What lesion location is characteristic of listeria monocytogenes?
Medullary abscess - cow
Medulla oblongata - sheep
What virus of equine can induce a encephalomyeltitis
Togaviruses
EEEV.
WEEV
VEEV
West Nile virus
Equine herpes virus
Horse with ..
Ataxia
Paresis
Paralysis (bladder paralysis is common)
Vasculitis -> thrombosis and infarction
Herpesvirus
Bovine necrotizing meningioencephalitis is caused by _________ and bovine meninoencephalomyelitis is caused by ________
BHV5; BHV1 (bovine rhinotracheitis)
What inclusion bodies can be found in a rabies infected animal?
Negri bodies
In dogs if humoral response in inadequate, what virus will spread hematogenously to the brain and choroid plexus infecting astrocytes and microglia?
Canine distemper virus
-paramyxovirus
Also see respiratory, conjunctival urinary tract infections, enamel hypoplasia and hyperkeratosis
In a canine distemper infection, what will you see histologically?
White matter vacuolation (intramyelinic edema)
Demyelination
Spongiform change
Perivascular cuffing
Intracytoplasmic and intranuclear inclusion bodies
What form of FIP can result in leptomeningitis, chrorioependymitis, focal encephalmyelitis, and opthtalmitits
Non-effusive (dry) form
What causes a neurological disease in young kids and causes arthritis/bursitis in adult goats?
Caprine arthritis encephalitis (CAE) syndrome
Where are the lesions in kids infected with CAE?
Mainly in caudal brain stem and spinal cord - demyelination encephalomyelitis
What is the most common disease associated with multifocal or asymmetric neurological deficits in horse?
Equine protozoal myeloencephalitis (EPM) -> sarcocystis neurona
-sudden/gradual onset of pelvic limb paresis and ataxia
What is the lifecycle of sarcosystis neurona ?
Sporocyts shed in opossum feces -> ingested by horse -> rep in CNS
How can infection by sarcocystis neurona be differentiated from wobbler syndrome and herpesvirus myeloencephalitis ?
Asymmetry of clinical signs
What are the most common cause of verminous encephalomyeltitis in the horse?
Halicephalobus gingivalis
Strongylus vulgaris
What protozoa of cats causes a non-supperative encephalitis
Toxoplasma gondii
Cysts containing bradyzoites
What is the etiology of transmissible spongiform encephalopathies?
Prions proteins (conformation change)
Name the TSE in.. sheep -> Cat -> Mink -> Deer and elk -> Bovines
Scrapie Feline spongiform encephalopathy Mink spongiform encephalopathy Chronic wasting disease Bovine spongiform encephalopathy
In a moo cow
Aggression Incoordination Abnormal posture Hypermetria Progressive weakness Decreased milk production and emaciation
BSE
In dogs.. Rickettsial disease
____________ will cause a vasculitis and _______________ will cause a non-suppurative meningitis/meningococcal-encephalitis
Rocky mnt spotted fever; ehrlichia canis
In a little cat brain you see multifocal lesions filled with viscous mucus exudate
EDx?
Cryptococcus neoformans
-> mucopolysaccharide capsule of yeast
Tumor arising form the pleura/ subarachnoid mater?
Menigioma
Tumor arising from within the choroid plexus with a granulated appearance, non-infiltrating
Choroid plexus papilloma
What type of tumor arises form the glial cells?
Glioblastoma
Tumor in the cerebellar hemisphere
Medulloblastoma
