EIM 11 Neuro

Question 1

Age predilection for grass sickness is

Answer 1

young, mature, 2-7yo​

Question 2

Risk factors for grass sickness are

Answer 2

grazing
age​ 2-7
time of year - spring and early summer​
movement to a new property/paddock​
increased stocking density​
low serum anti-body titers against Clostridium botulinum toxins​

Question 3

Neuroborreliosis CS

Answer 3

behavioural changes, hyperesthesia, gait abnormalities, cranial nerve deficits, neck stiffness, muscle atrophy/fasciculations​

Question 4

Head shaking is more likely to be seen in

Answer 4

spring/early summer months​

Geldings, thoroughbreds, younger adults (7-9yo)​

Question 5

The most common secondary neoplastic condition affecting the CNS of horses:​
​

Answer 5

lymphoma

Question 6

Leukoencephalomalacia in horses is caused by: ​

Answer 6

MOLDY CORN
Caused by ingestion of the mycotoxin fumonisin B1, a metabolite of Fusarium moniliforme​

Gross - liquefactive necrosis of cerebral hemispheres

Question 7

Nigropallidal Encephalomalacia is caused by:​

Answer 7

yellow star thistle / Russian knapweed​
chronic, long-term ingestion
​
Bilateral softening and necrosis in areas of the globus pallidus and substantia nigra​

Question 8

Horner’s syndrome is a collection of clinical signs associated with dysfunction of the

Answer 8

sympathetic nerve supply to the head and neck​

Note the ’triad’ = ipsilateral ptosis, third eyelid prolapse and miosis​
Third eyelid prolapse is due to enophthalmus ​
Sweating along the side of the face

Question 9

Normal vestibular nystagmus is: ​

Answer 9

moving head side to side, eyes move slowly in the opposite direction​

Question 10

8th cranial nerve unilateral peripheral injury

Answer 10

Head tilt (poll deviation) towards the side of the lesion​ Horizontal nystagmus, fast phase away from side of the lesion​

Question 11

Guttural pouch disease can damage what near structures

Answer 11

Cranial nerve 9 (glossopharyngeal) ​
A branch of cranial nerve 10 (vagus)​
Injury to the internal carotid nerve, which contains postganglionic sympathetic fibers … resulting in Horner syndrome​

Question 12

Which WBC type is most common in normal CSF (70-90%)​

Answer 12

Small mononuclear cells 70-90%​

Large mononuclear cells 10-30% - increase #s in axonal degeneration​

Rarely may see a neutrophil – increase #s with inflammation (including meningitis, encephalomyelitis, parasitism)​

Eosinophils only occasionally if there’s parasitism or other severe inflammatory process​

Question 13

CSF protein concentration

Answer 13

higher in LS than AO fluid​

NORMAL range 20-124mg/dL ​

Question 14

EHV-1 causes

Answer 14

mainly causes abortions, early foal deaths, and respiratory disease in young horses, and uncommonly causes myeloencephalopathy

Question 15

EHV-4 causes

Answer 15

causes clinical disease of the respiratory tract, sporadic abortions, and has been implicated in isolated cases of myeloencephalopathy​

Question 16

alpha herpes viruses

Answer 16

EHV-1, 4, 3

Question 17

gamma herpes viruses

Answer 17

EHV-2, 5

Question 18

neurologic dz and herpes

Answer 18

The majority of neurologic EHV infections are infections in individuals who have have exposed before​

Affected horses have higher titres at the onset of disease ​

The acute onset signs are a result of vasculitis​, Immune complexes / type III hypersensitivity reactions

The most infectious neurotropic strains are frequently isolated from brain tissue on PM​

Almost all horses are febrile at the onset of neurologic disease

Question 19

IN CONTACT HORSES TO A HERPES CASE SHOULD BE ISOLATED FOR:​

Answer 19

30 days in their current location (or until foaling if mares)​

Traffic of horses and human beings on the premises should be minimized, and movement of horses onto and off of the infected premises should be suspended until at least 3 weeks after resolution of acute signs in the last clinical case or until tests show that virus transmission is no longer occurring​

Question 20

EMND affects

Answer 20

A) motor neurons in the spinal cord ventral horn cells​
B) the brain stem​
C) lower motor neurons

Question 21

HOW LONG DOES IT TAKE TO INCREASE PLASMA VITAMIN E WITH SUPPLEMENTATION?​

Answer 21

5000-7000 IU/horse/day for 6 weeks

goal is 2ug/ml or greater plasma conc

Question 22

Horses sleep how much?

Answer 22

3-4 hours per day

split up into 6 phases of rest and sleep through out the night

Question 23

Can horses get rem sleep in sternal?

Answer 23

yes if they support their head – loss of muscle tone p 608​
REM sleep should compromise 15% of total sleep​
If they enter while standing due to sleep deprivation they may fall

Question 24

WHAT ARE GOALS OF TBI TREATMENT?

Answer 24

A) Delivery of oxygen to undamaged brain tissues​
B) reduction of intracranial pressure​
C) maintaining blood glucose concentrations of 120-140mg/dl​
E) combat inflammation with NSAIDS, DMSO, Vit E​

Question 25

WHICH REGION OF SC INJURY MAY CAUSE “DOG SITTING”?

Answer 25

thoracolumbar

Question 26

Which is not one of the sites that neuron 1 (first-order neuron) of the vestibular system receives impulses from?

Answer 26

optic nerve

Question 27

T/F The cristae record movement of the head.

Answer 27

true

Question 28

Turning the head to the left results in a horizontal nystagmus with fast phase to the ____. The accompanying slow phase is in a direction _____ body motion and allows the eyes to fix on a stationary image.

Answer 28

left

opposite to

Question 29

Because of its proximity to the vestibular nerve where they are associated closely with the petrous temporal bone and enter the internal auditory meatus together, which nerve is commonly affected along with the vestibular nerve by a single disease process?

Answer 29

CN VII

Question 30

With peripheral vestibular disease, there is ventral deviation of the poll

Answer 30

towards the affected side

Question 31

With peripheral vestibular disease, there is circling

Answer 31

towards the lesion

Question 32

With peripheral vestibular disease, there is extensor

Answer 32

hypotonia ipsilateral to the lesion and mild hypertonia of the extensor muscles on the contralateral side.

Question 33

What distinguishes central from peripheral vestibular disease

Answer 33

proprioceptive deficits

Question 34

Issues in what two anatomical areas can cause pathologic nystagmus?

Answer 34

vestibular

cerebellum

Question 35

Which is believed to be the most common etiology of botulism in foals?​

Answer 35

toxin secretion by ingested spores

Question 36

Occipitoatlantoaxial malformation, cerebellar abiotrophy, and epilepsy have all been described in…​?

Answer 36

arabian foals

Question 37

Which of the following medications should be used to treat status epilepticus?

Answer 37

pentobarbital 2-10 mg/kg iv once

Question 38

The proposed mechanism of action for IV magnesium sulfate in the treatment of HIE is…​

Answer 38

NDMA-receptor antagonist effects, cell wall stabilization, and inhibition of free radical production

Question 39

EMND clinical signs

Answer 39

muscle atrophy, muscle twitching, weakness, weight loss, and sweating. Affected horses may carry their heads lower than normal and lie down for longer periods

Question 40

EMND diagnosis

Answer 40

sacrocaudalis dorsalis medialis biopsy

Question 41

eNAD / EDM clinical signs

Answer 41

ataxia, usually onset around 6 mos

Question 42

eNAD / EDM diagnosis

Answer 42

postmortem

biomarker of axon damage, phosphorylated neurofilament heavy subunit (pNF-H,) in serum and/or cerebrospinal fluid (CSF)

Question 43

Cause of EMND

Answer 43

typically occurs in older horses >16 years old that have been vitamin E deficient for >18 months