Session 17 - Neurology I Flashcards
1
Q
What are three viruses that can cause arthrogryposis?
A
Akabane virus
Rift Valley Fever
Cache Valley
2
Q
What is arthrogryposis?
A
Crooked, curved, or fused joints
3
Q
What causes swayback in sheep?
A
Copper defiviency
4
Q
What happens with a ewe’s fetus when veratrum californicum ingestion?
A
Cyclopia, holoencephaly, arhinencephaly
5
Q
At what point in gestation does a ewe have to ingest veratrum californicum to hurt the fetus?
A
14th day
6
Q
What can happen to the fetus in sheep infected with the blue tongue virus? (at specific time points)
A
50 days - Sever hydraenecephaly
75 days - Scattered proencephalic cysts
100 days - Scattered glial nodules
7
Q
Term: Small brain size
A
Microencephally
8
Q
Term: Hydranencephaly
A
Absence of cerebral hemispheres with filling and dilation of lateral ventricles by CSF
9
Q
Term: Porencephaly
A
Cystic cavities in partially formed cerebral hemispheres
10
Q
Term: Lissencephaly
A
Failure of gyri + sulci to develop
Smooth cerebral surface
11
Q
What is thought to cause lissencephaly?
A
Arrest of the normal migration of neurons during development
12
Q
What animals is lissencephaly normal in?
A
Rodents, Birds, and reptiles
13
Q
Term: Dysraphism
A
Developmental anomaly of neural tube due to defective fusion
14
Q
What are common lesions seen with dysraphism?
A
Hydromyelia + Syringomyelia + Meningocele
15
Q
Term: Hydromyelia
A
Dilation of the central canal
Will see pooled CSF
16
Q
Term: Syringomyelia
A
Cavitation of spinal cord parenchyma
17
Q
Term: Meningocele
A
Herniation of meninges through bone defect
18
Q
What are the two kinds of meningocele?
A
Meningoencephalocele
– and –
Meningomyelocele
19
Q
Term: Meningoencephalocele
A
Herniation includes the brain
20
Q
Term: Meningomyelocele
A
Herniation includes spinal cord
21
Q
What are common forms of Dysraphism?
A
Spina bifida + Cranium bifidum + Anencephaly
22
Q
What is the most common area for spina bifida to occur?
A
Lumbo-sacral region
23
Q
What cat is commonly seen with spina bifida?
A
Manx
24
Q
What type of spina bifida do manx cats tend to get?
A
Coccygeal veterbrae, normally mild
25
What occurs in the severe form of spina bifida?
Skin does not cover the lesion
Posterior arches of vertebra remain open
Neural groove is exposed
26
What occurs in the intermediate form of spina bifida?
Meningomyelocele
-- or --
Meningocele
Covered by skin
27
What occurs in the mild form of spina bifida?
Posterior arch of 1+ vertebra is missing
28
What is another name for the mild form of spina bifida?
Spina bifida occulta
29
What infection can cause anencephaly in fetal goats?
Cache valley fever
30
What are the three mechanisms that can cause hydrocephalus?
Compensatory
Obstructive
Over production
31
What occurs with hydrocephalus with the compensatory mechanism?
Fluid fills space created by a loss or failure of development of surrounding parenchyma
32
What is it called when there is a loss of parenchyma in the brain and CSF takes it's place?
Hydrocephalus ex-vacuo
33
What occurs with the obstructive mechanism of Hydrocephalus?
Fluid accumulates in front of an obstruction
| Or behind when there is a block in the ability for the absorption of CSF into the venous system
34
Where is the most common obstruction that causes hydrocephalus?
Mesencephalic aqueduct
35
What can cause a over production of CSF?
Chororid plexus papillomas
36
What breed of dog most commonly gets congenital hydrocephalus?
Toy breeds
37
What causes congenital hydrocephalus?
Fusion of the rostral colliculi = obstruction of the aqueduct
38
What occurs with the fusion of the rostral colliculi?
Dilation of ventricles due to increased CSF pressure
| Leads to compression atropy
39
What happens if the fusion of the rostral colliculi occurs before skull bones have ossified?
Enlargement of the cranium occurs
| Open fontanelles
40
When can cerebellar malformations occur? Why?
Transplacental or early neonatal
| There is still cerebellar development after birth
41
What clinical signs are seen with cerebellar lesions?
Base-wide stance
Spastic hypermetric gait
Loss of balance/ataxia
42
What are three infections that can cause congenital cerebellar hypoplasia?
Feline panleukopenia
Border disease
Bovine Viral Diarrhea
43
How does feline panleukopenia cause cerebellar hypoplasia?
Virus infects actively dividing cells
44
What layer is most focused on by feline panleukopenia virus?
External germinal layer
45
When is there the most activity in the external germinal layer?
Birth till about 2 weeks post natal
46
What is seen in the brain in a fetus infected with borders disease?
Partial or complete absence of cerebellar vermis
Fourth ventricle dilates
Stenosis of aqueduct and hydrocephalus
47
What syndrome occurs with partial or complete absence of the cerebellar vermis?
Dandy-walker syndrome
48
When does a fetus have to be exposed to BVD to cause problems?
100 to 200 days of gestation
49
What is seen in a fetus that is infected with BVD?
Nonsuppurative inflammation
Necrosis
Hemorrhage
Edema
50
Term: Laminar necrosis
Pattern of layered necrosis
51
What is seen histiologically with laminar necrosis?
Neurons will appear bright red, angular, shrunken with a pynotic eccentric nuclei
Bands of edema
52
Where does laminar necrosis occur?
Cortical grey matter
53
Term: Polioencephalomalacia
Softening of the grey matter
54
What can cause polioencephalomalacia?
Thiamine deficiency
55
What are the features of neuronal necrosis?
Red deads - bright red neurons
Angular
Shrunken
Pyknotic, eccentric nuclei
56
What are the four differentials for cerebrocortical laminar necrosis?
Lead poisoning
Thiamine deficiency
Water deprivation + Salt poisoning
Hypoxia
57
What are the clinical signs of lead toxicity?
Restlessness
Head pressing
Tremors, seizures, blindness
58
What is seen in horses with lead toxicity?
Laryngeal paralysis
59
What is seen in calves with lead toxicity?
violent convulsions
60
What is seen with acute lead toxicity?
Cerebral edema
61
What is seen with chronic lead toxicity?
Laminar necrosis + Peripheral neuropathy
62
What is can lead toxicity be confused as?
Thiamine deficiency
63
What are other terms for thiamine deficiency?
Polioencephalomalacia
| Cerebrocortical necrosis
64
What is another name for thiamine deficiency in ruminants?
Blind staggers
65
What is another name for thiamine deficiency in carnivores?
Wenicke's disease
66
What is the presentation of thiamine deficiency?
Depression
Blindness, Ataxia
Extensor rigidity of lumbs
Seizures, coma, death
67
Why are cattle predisposed to thiamine deficiency?
Have thiaminase producing bacteria in their gut
Young cattle have lack of this bacteria
Rumen acidosis can also kill these
68
What are the two bacteria types that produce thiaminase?
Bacillus + Clostridium
69
What lesions are seen in cattle with thiamine deficiency?
Neuronal necrosis in all layers of cortical gray matter
| Prominent edema in deep lamina
70
What gross lesions are seen with thiamine deficiency?
yellow discoloration of cortical surface
These will fluoresce under UV light
Reactive vascular endothelial and vascular proliferation
+/- cortical/meningeal perivascular infiltrates of macrophages
71
Where does necrosis tend to occur in carnivores with thiamine deficiency?
Brainstem nuclei, mostly in the caudal colliculi
72
What are two other ways to describe yellow star thistle poisoning?
Striatonigral degeneration
| Nigropallidal encephalomalacia
73
What causes yellow star thistle poisoning?
Centaurea solsitialis
74
Where is yellow star thistle poisoning most common?
Northern California + Colorado
75
How long after ingestion of Centaurea solsitialis does it take to see symptoms?
1 to 3 months
76
What lesions are seen with yellow start thistle poisoning?
Bilateral, focal malacia of anterior globus pallidus, and substantia nigra
77
How does salt poisoning tend to occur in swine?
High salt content in diet + period of water deprivation followed by large water consumption
78
What lesions are seen with salt poisoning?
Laminar necrosis
| Perivascular and meningeal eosinophils
79
What are the clinical signs of hypoglycemia?
Irritability, seizures, and coma
80
What can cause hypoglycemia?
Chronic liver disease
Insulin secreting tumor of pancreatic islets
Starvation
81
What lesions are seen with acute hypoglycemia?
No gross changes
| Histologically will see changes in CNS
82
What happens with more chronic forms of hypoglycemia?
Neuronal degeneration in cerebral cortex
| Axonal degeneration in peripheral nerves
83
What two things can be affected in disorders of myelination?
Glial cells + Myelin sheath
84
What are the glial cells of the PNS?
Schwann cells
85
What are the glial cells of the CNS?
Oligodendrocytes
86
What are the resulting defects of myelination disorders?
Demyelination
Dysmyelination
Hypomyelination
87
Term: Demyelination
Loss of normal myelin around axons
88
Term: Dysmyelination
Formation of abnormal myelin during development
89
Term: Hypomyelination
Partial or complete lack of myelin development
90
What are considered leukodystrophies?
Dysmyelination + Hypomyelination
91
What viruses can cause hypomyelination?
Hog cholera
BVD
Border disease
92
When does Afghan myelopathy present?
3 to 13 months of age
93
How does Afghan myelopathy present?
Over 7 to 10 days see mild hind-limb weakness + ataxia to hind limb paralysis
94
What lesions are seen in Afghan myelopathy?
Bilateral, lateral + vental (sometimes dorsal) column destruction/degeneration of myelin
Axons are sparred
95
Where are lesions most sever in Afghan myelopathy?
Thoracic
96
What cellular response is seen in afghan myelopathy?
Macrophage response
No acute inflammation
Little astrocytic response
97
What two stains used to stain spinal cords?
LFB + PAS
98
What color does LFB stain myelin?
Blue
99
What party of the brain is affected in cheetah leukoencephalopathy?
Cerebral cortical white matter
100
What is seen histiologically in cheetah leukoencephalopathy?
Florid reactive astrocytosis
101
What lesions are seen with Cheetah leukoencephalopathy?
Hydrocephalus ex vacuo
| Pitting and roughening of the white mater tracts
102
Term: Neuronal abiotrophy
Premature degeneration and death of discrete populations of neurons
103
What are the clinical signs of cerebellar cortical abiotrophy?
Ataxia + Head tremor
Symmetric hypermetria
Spasticity
Broad-based stance + Loss of balance
104
What is the normal onset of symptoms from cerebellar cortical abiotrophy?
4 to 16 weeks
105
What lesions are seen with cerebellar cortical abiotrophy?
Gross loss of cerebellar size in severe cases
106
What is seen histiologicaly with coritcal abiotrophy?
Marked neuronal depletion with gliosis
107
What is commonly seen in a canine's brain due to aging?
Meningeal fibrosis
| Generalized cortical atrophy
108
What is seen grossly that hints at generalized cortical atrophy?
Widened sulci + Narrow gyri
109
What is seen grossly that hints at meningeal fibrosis?
White opacification
110
Where is meningeal fibrosis most apparent?
Sulci
111
What is dural ossification?
FORM OF METAPLASIA
| Mature bone forms within meninges of spinal cord
112
Who mostly commonly gets dural ossification?
Large breed dogs
| German shepherds
113
What is another name for dural ossification?
Ossifying pachymeningitis
114
What should be noted when using the name ossifying pachymeningitis?
Not an inflammatory lesion
115
At what age do you start to see dogs with Canine cognitive dysfunction syndrome (CDS)?
Over 11 years old
116
What things do you see with a dog that has CDS?
Disorientation
Decreased or altered response to family
Sleep disturbances
Decreased activity
117
What are some possible mechanisms of CDS?
B-amyloid accumulation
Increased activity of pituitary-adrenal axis
Loss of cholinergic receptors
Neuronal loss
118
What happens with equine choroid-plexus cholesterol granuloma?
Cholesterol aggregates within CT
119
Who is choroid-plexus cholesterol granuloma most common in?
Older horses
120
Where does cholesteatoma tend to occur in the brain?
Ventricles and Meninges
