The Neurological Horse with Normal mentation: Miscellaneous

Question 1

Define head-shaking

Answer 1

involuntary sudden violent repetitive movements of the head dorso-ventrally, horizontally or rotatory

Question 2

what causes the majority of head-shaking cases

Answer 2

idiopathic causes - thought to be due to trigeminal-mediated hyperactivity

Question 3

List 6 possible triggers form head shaking

Answer 3

bright light
allergies
sinusitis
otitis
GP mycosis
structural disease

Question 4

what causes trigeminal mediated head shaking

Answer 4

spontaneous discharges arising from select neurons within the trigeminal nerve, whose threshold for firing has been altered

Question 5

Describe how we can diagnose head shaking

Answer 5

identify potential triggers
perform a full exam of all aspects of the head (ocular, dental, URT, nerve blocks, X-rays, CT, otoscopy)

Question 6

Describe how we can medically treat head-shaking

Answer 6

remove the triggers

there are a large number of reported treatments - the most effective are:
Cyproheptadine + Carbamazepine, nose nets and ocular sunglasses

Question 7

Describe how can we surgically treat head-shaking

Answer 7

Infraorbital neurectomy with cryotherapy, chemical sclerosis of infraorbital nerve, caudal compression of infraorbital nerve

• none of these work amazing and some have severe complications

Question 8

What is narcolepsy

Answer 8

spectrum of CND disorders characterised by episodes of excessive sleepiness, muscular weakness and REM onset sleep

Question 9

What is sleep-deprivation

Answer 9

episodes of collapse due to lack of regular resting/ sleep

Question 10

what can cause sleep-deprivation

Answer 10

pain or fear or stress

Question 11

List the clinical signs of sleep- deprivation

Answer 11

staggering
lowered head and neck
buckling of thoracic limbs
unexplained abrasions

Question 12

Describe how to treat sleep-deprivation

Answer 12

oral phenylbutazone
thick bedding
large stable
move to an inside barn
remove rugs

Question 13

Describe shivers

Answer 13

Progressive, chronic neuromuscular disease in horses characterized bygait abnormalities when backing up, trembling of the tail while held erect, trembling of the thigh muscles and a flexed and trembling hind limb when held

Question 14

List the clinical signs of shivers

Answer 14

abnormalities when backing up
trembling tail while held erect
trembling thigh muscles
flexed and trembling hind-limb when held

Question 15

what can cause shivers

Answer 15

damage of the deep cerebellar nuclei

Question 16

Describe how to treat shivers

Answer 16

NO treatment