Equine Med- Neuro

wilsbach's version from 2016-04-29 21:40


CNs live where? Brainstem
Question Answer
which is afferent and efferent-- of the sensory and motor system?Sensory is afferent, Motor is efferent (The A is towards-- opposite of the CVS)
where the LMNs and UMNs live (pic)
seizure means _________ brain dz1*
how do you know olfactory is ok?generally if they eat, they can smell. Rarely abnormal, usually dz of air passages.
should you do gag reflex in a horse?no you will get hurt
If the horse is eating normally.. what CNs can you determine are ok?I- olfactory IX- glossopharyngeal X- Vagus XII- hypoglossal
how to test CN II (3 ways)optic- (1) walk through maze or optical course. (2) menace (II and VII) but make sure you aren't touching the tactile hairs. (3) PLR ( II and III) there is direct and indirect
opening the eyelid is controlled by what CN?3
CNs responsible for position of the globe in the orbit, and pupillary constriction3,4,6 makes the eyes twitch (oculomotor, trochlear, abducens)
2 possible nerves which can cause strabismus?4 or 6. but strabismus is rare in horses.
CN III does? What will it look like if it is abnormal?oculomotor- All muscles of eye (except Dorsal oblique muscle / Lateral rectus). Abnormal: ventrolateral strabismus (three looks down and to the side when being sassy)
CN IV does? What will it look like if it is abnormal? trochlear- Dorsal oblique muscle. Abnormal: dorsomedial strabismus (a pully to make you look up to god)
CN VI does? What will it look like if it is abnormal?abducens- controls Lateral rectus + retractor bulbi . Abnormal: Medial strabismus. (Abs in the Middle)
3 branches of the trigeminal nerve, and where they innervate?opthalmic, maxillary, mandibular
how can you test the 3 branches of the trigeminal nerve separately?Ophthalmic branch- medial canthus (touch, blink), Maxillary branch- lateral canthus (touch, blink), mandibular branch- pinch mandibular region
which nerve is motor to mm of mastication?trigeminal
how do you know if there is atrophy of mm of mastication?see facial crest really well
what is the motor component of the trigeminal nerve?MANDIBULAR N: Motor to muscles of mastication (jaw tone)
motor and sensory component of the facial nerve? where do they separate?mm to mm of facial expression. sensory: lacrimal and salivary glands. Separate at petrous temporal bone.
if muzzle is deviated to the left, where is the damage?left side still working, R side flaccid, so the R facial n is damaged
lacrimation/salivation controlled byCN 7
CN 8 functionVestibulocochlear- the cochlear part= hearing (hard to assess.) Vestibulo= Head orientation with relationship to gravity. A physiological nystagmus is normal- When head rapidly turned, fast phase in direction of movement
physiological nystagmus- fast phase should be in what direction?direction of the movement
what CNs does the slap test test, and how do you perform this test?palpate larynx, and slap at level of withers, will feel abduction of larynx (but need good sensitivity in your fingers). Tests IX, X, XI (glossopharyngeal, vagus, and accessory)
what nerve does tongue tone?hypoglossal (XII)
Which is normal, and what nerves are responsible for this L is normal, CN IX and X (dorsal displacement of soft palate)
unilateral atrophy of the tongue is probably..EPM
Cutaneous trunci / Panniculus reflex is for what?helps locate lesion site
what is horners syndrome? Reasons it can happen? CSs?Damage to sympathetic fibers. Can be from Brachial plexus avulsion, Injury to cranial Thoracic Sp. Cord, Cervical Symp. trunk injury(Tumor / hematoma / trauma), or guttural pouch dz. CS: MIOSIS/PTOSIS, Enophthalmia / Sweating ipsilat. side
localized sweating, think...HORNERS
Manipulative tests you can conduct after a gait analysis? Walk/Trot, Tail pull / sway test, Curb / pole, Circle, Back up, Rapid stop, foot placement, blindfold, slope/incline
tail pull/sway test- how do you do this?someone behind horse holding tail, pull as walking, see how easy horse can regain normal stride- weak and ataxic horses will have difficulties.
why do you do a circle test?check placement of hindlimbs
what will a failed rapid stop test look like?they sort of bunny hop bc cant stop immediately. but on two hind limbs will make 2 or 3 stops
if there is no cerebral function, will the horse be able to walk?Animals can walk without cerebral function! Deficits seen when asked to perform complex motor activities
what is paresis, what are signs of it on your assessment?paresis is weakness. Toe dragging and wear, “Bounce” to stride, Difficulty backing, Muscle fasciculations
tests you can do to test for paresis?Sway test / Tail pull, Curbs, incline, (hopping)
what is ataxia? CSs of it?Loss of perception of the movements and position of the body and limbs. Independent of vision. CS: abnormal stance, abnormal / inconsistent foot placement, side to side (swaying) motion of the trunk
tests for ataxia?circling, incline, obstacles, move with head elevated, "blindfold"
what does hypometria look like? Ataxia characterized by under-reaching. There is Decreased motion at joints and limb "stiffness"
what does hypermetria look like?Ataxia characterized by over-reaching. there is Exaggerated joint motion and a "high stepping" gait
what are some things youd see with proprioceptive deficits?abduction of limbs, crossing of limbs, spinning, circumduction, knuckling/buckling
what are the two sites to collect CSF, and which requires GA?(1) Atlantooccipital site: GA required (2) Lumbosacral: GA not required
lumbosacral CSF collection site is where, how can the horse be positioned?L6-S1 ( the junction of lumbar and sacral. not surprising). can be done standing or in lateral recumbency. You will feel tuber sacrale on either side and and there is a depression palpable at that level. need long 6-7 inch long 18G needle
***normal TP and cellularity and color of CSF?Low TP <100 mg/dl, Low cellularity <6 WBC, CLEAR, and NO RBCs (consider collection site)
what is xanthochromia? what does it mean?Yellow tinged CSF, means there might have been trauma before- RBCs have been there
how many rads for cervical spine usually?Typically requires 3 – 4 films
how many vert bodies in the horse?7
whats myelography? risks?rads with spinal contrast- myelogram needs GA, and can transiently worsen clinical signs. Pre-treat with NSAIDs. If gonna put 50 cc in, take 50cc out
myelograms are CI when?when evidence of inc intracranial pressure
what are scout films?Flat / plain films first
how do you know if there is high IC pressure, which would make you think twice about doing a myelogram? if put needle in and fluid is just coming out very easily- know there is high pressure. If it's spurting out, def dont do it.