Unit 3 - Neuro (CN, Reflexes, Diagnostics, Definitions) Flashcards

1
Q

What are the four functionally different anatomic areas of the nervous system?

A

Cerebrum
Cerebellum
Brainstem and cranial nerves
Spinal cord and peripheral nerves

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What are the three etiological categories of nervous illnesses?

A

Acquired biologic
Acquired nonbiologic
Congenital or hereditary

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What should be observed on distant neurologic examination?

A

Mentation, posture, and gait

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What spinal reflexes can be assessed in all ruminants?

A

Panniculus, withdrawal of forelimb/hind limb, patellar, and perineal reflex

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What are the 6 broad types of abnormalities in mentation in ruminants?

A
  1. Excitement, mania, or hyperesthesia
  2. Seizures
  3. Depression
  4. Aimless circling, stupor, or coma
  5. Abnormal vocalization
  6. Blindness
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

T/F: Aimless circling and tight circles associated with vestibular lesions are caused by the same process.

A

False - aimless circling is due to serevral disease

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What is gait?

A

The coordinated functioning of the cerebral cortex, extrapyramidal basal nuclei, and red nuclei which stimulates the flexor muscles and simultaneous inhibition of extensor muscles

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What can cause gait abnormalities?

A

Cerebellar, brainstem, spinal cord, and peripheral nerve lesions

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

How do you assess conscious proprioception in ruminants?

A

During ambulation by placing obstacles in enclosures/alleyways

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

If an animal is halter broke, how do you assess conscious proprioception?

A

Walking in tight circles, walking across/up a curb, walking up and down a hill, and pulling the tail while walking strait

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What neurologic signs can suggest the possible presence of proprioception deficits and exaggerated spinal reflexes?

A

Presence of ataxia, hypermetria, and truncal sway

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What is posture maintained by?

A

The trunk muscles and extensor muscles of the proximal limbs

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What facilitates posture?

A

The vestibulospinal and reticulospinal tracts from the medulla and pons

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What are the three main aspects of posture?

A

Head, body, and limbs

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What processes sensory input from pressure/stretch receptors in the limbs/body, vestibular system, and visual inputs?

A

The brainstem, cerebellum, and cerebrum

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Abnormal head posture (continuous head tilt) indicates what?

A

Central or peripheral vestibular disease

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What can cause abnormal trunk posture?

A

Congenital or acquired disorders such as scoliosis, lordosis, and kyphosis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What are some abnormal limb postures that can result from UMN or LMN disease?

A

Inappropriate positioning, weakness, knuckling, and a base-wide stance

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

What does the menace response evaluate?

A

The entire visual pathway, CN VII, and the cerebellum

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

What cranial nerves are involved in the menace response?

A

CN II and CN VII

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

T/F: The menace response is often absent in neonatal ruminants.

A

True

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

What cranial nerves do pupillary reflexes assess?

A

CN II and CN III

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

If the intraparenchymal visual pathways are affected (central or cortical blindness) what will the menace response be? The PLRs?

A

Menace - absent on the contralateral side of the lesion

PLR - intact

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

If the extraparenchymal visual pathways (peripheral blindness) are affected, what will the menace response be? PLRs?

A

Menace - blindness on the size of lesion; absent

PLRs - abnormal

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

What muscles does the CN III control?

A

Dorsal, ventral, and medial rectus muscles
Ventral oblique muscle
Levator palpebrae muscle

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

What do lesions of CN III result in?

A

Ipsilateral ventrolateral strabismus and mydriasis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

What muscle does CN IV innervate?

A

Dorsal oblique muscle

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

What do lesions of CN IV result in?

A

dorsolateral strabismus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

What does CN VI innervate?

A

The lateral rectus and retractor bulbi muscles

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

What do lesions of CN VI result in?

A

Medial strabismus with a more forward positioning of the globe
Failure to retract the globe during assessment of the palpebral (or corneal) reflex

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

T/F: The eyes of ruminants should try to maintain focus straight ahead, the result being that the eye moves slowly in the opposite direction of the head movement and then ‘jump’ quickly back towards the direction movement.

A

True

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

What are the three branches of the trigeminal nerve (CN V)?

A

Ophthalmic, maxillary, and mandibular

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

While all branches of CN V have sensory fibers, which branch has motor fibers as well?

A

Mandibular

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
34
Q

Lesions to the mandibular branch of CN V result in what clinical signs?

A

Muscle asymmetry/loss, flaccid or lowered jaw, inability to close the jaw, inability/reduced mastication with dropping of feed and drooling, and protrusion of the tongue.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
35
Q

What do the corneal and palpebral reflexes test?

A

Sensory - CN V

Motor - CN VII

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
36
Q

What branch of the trigeminal is assessed by touching the medial canthus? Lateral canthus?

A

Medial canthus - ophthalmic branch

Lateral canthus - maxillary branch

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
37
Q

How is sensory function of the mandibular branch of CN V tested?

A

Touching/pinching the face, including the base of the ear

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
38
Q

How is the consciously mediated, coordinated movement of the head away from noxious stimuli assessed?

A

Applying stimuli to the nasal septum

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
39
Q

What CN tests test CN VII?

A

Menace response, palpebral reflex, corneal reflex

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
40
Q

What does CN VII innervate?

A

Facial muscles of expression
Parasympathetic innervation to the lacrimal gland, and mandibular and submandibular salivary glands
Symmetry, posture, and movement of the eyelids, lips, and ears

41
Q

What can lesions of CN VII cause?

A

Ear droop, lack of ear movement, eyelid droop (ptosis), and deviation of nasal philtrum
Lack if muzzle tone can result in protrusion of the tongue and driiping
Exposure keratitis

42
Q

What is the vestibular portion of CN VIII responsible for?

A

maintaining head position and other structures relative to the pull of gravity

43
Q

What is the cochlear division of CN VIII responsible for?

A

hearing

44
Q

What are clinical signs associated with vestibular dysfunction?

A

Head tilt, nystagmus, ataxia, incoordination, positional strabismus, and head tilt towards the lesion (often will fall on the side of the lesion)

45
Q

What do CN IX and CN X innervate?

A

Pharynx, larynx, and tongue
Striated muscles of the esophagus
CN X - abdominal viscera including the forestomach

46
Q

How is the gag reflex performed?

A

Place a tongue depressor on the back of the tongue, which normally the animal should ‘throw’ back up

47
Q

What does CN XII innervate?

A

Motor innervation of the tongue, controlling both protrusion and retraction

48
Q

What signs are indicative of a CN XII lesion?

A

Difficult prehension and mastication feed
Unilateral damage results in a tongue to twist toward the affected side (if it is a facial nerve lesion the tongue will twist away from the lesion)

49
Q

Evaluation of spinal reflexes is best achieved in what position?

A

Lateral recumbency

50
Q

T/F: Spinal reflexes require conscious or voluntary input and test the integrity of LMN, but also provide information on UMN influence on LMN

A

False - they do NOT require conscious or voluntary input

51
Q

Exaggerated (hyper-reflexive) reflexes are often observed with (LMN/UMN) lesions. A reduced/diminished or absent reflex indicates (LMN/UMN) lesions.

A

UMN

LMN

52
Q

What does the extensor reflex test?

A

The radial nerve function of the forelimb

53
Q

How do you perform the extensor reflex test?

A

Place the animal in lateral recumbency
Place a hand under the foot
With the limb positioned in extension and push it gently

54
Q

What is the normal reflex for the extensor reflex?

A

For the animal to push back against your hand

55
Q

What extensor reflex response is indicative of LMN disease? UMN disease?

A

LMN disease - decreased or absence of resistance

UMN disease - Increased tone of the triceps muscle

56
Q

How is the panniculus reflex done?

A

Apply pressure on the cutaneous trunci starting caudally and move forward

57
Q

The reflex arc for the panniculus reflex is the sensory fibers from each dermatome enters the spinal cord and then ascends to the ___ and ___ segments.

A

C8 and T1

58
Q

How do you perform the withdrawal reflexes?

A

Apply adequate force and pinch the interdigital skin as well as the coronary band of each individual claw.

59
Q

What do the withdrawal reflexes require to be intact for the front limbs?

A

C6-T2 and the axillary, median, and ulnar nerves

60
Q

What do the withdrawal reflexes require to be intact for the back limbs?

A

L 5(6)- S1 and the sciatic nerve in the hind limb

61
Q

T/F: A cross extensor reflex can be normal in neonates but in mature ruminants it can indicated interference with the normal UMN pathways.

A

True

62
Q

What does the patellar reflex require to be intact?

A

L4, L5, and the femoral nerve

63
Q

What is the normal response to the patellar reflex?

A

Obvious and repeatable extension of the stifle

64
Q

What can cause an exaggerated patellar reflex response?

A

Both UMN damage and sciatic nerve damage

65
Q

What causes decreased patellar reflex responses?

A

Lesions of L4, L5, the femoral nerve, and myonecrosis and white muscle disease

66
Q

How is the perineal reflex done?

A

Pinching of the skin around the rectum

67
Q

What is required for an intact perineal reflex?

A

Intact spinal cord segments S2-S4 and the pudendal and caudal rectal nerves

68
Q

How is cerebrospinal fluid collected?

A

Palpate the hooks/wing of the ileum, and feel for depression slightly caudal to an imaginary line drawn in between the hooks. The spinal needle is placed in the lumbosacral space to the subarachnoid space

69
Q

What is the rule of thumb for the amount of cerebrospinal fluid that can be collected?

A

Approximately 0.5 ml per 5 kg of body weight can safely be removed

70
Q

What should normal cerebrospinal fluid look like?

A

Clear and colorless

71
Q

What is cloudy or turbid cerebrospinal fluid indicative of?

A

Increased white cell concentration

72
Q

What does a stable foam in cerebrospinal fluid indicate?

A

Icnreased protein concentration

73
Q

What are normal WBC and protein levels in cerebrospinal fluid in cattle?

A

< 3 WBC/dL

< 30 mg/dl protein

74
Q

What is the normal specific gravity of cerebrospinal fluid?

A

<1.010

75
Q

Define depression.

A

Decreased responsiveness to stimuli

76
Q

Define stupor.

A

Animal appears to be sleeping when undisturbed; mild stimuli will not induce arousal, but vigorous stimuli will induce arousal

77
Q

Define coma.

A

An unconscious state in which spinal reflexes can be normal, but vigorous noxious stimuli does not induce arousal

78
Q

Define seizure.

A

Involuntary episode of muscular activity that may be generalized or localized
If generalized - the animal becomes recumbent, has altered mentation, and has periodic episodes of muscular activity

79
Q

Define opisthotonus.

A

Dorsiflexion of the head and neck

80
Q

Define nystagmus.

A

Inappropriate and involuntary movements of the eyes; can be horizontal, vertical, rotary, or intermittent

81
Q

Where does the fast component of nystagmus typically point? Slow?

A

Fast - away from the side of the lesion

Slow - towards the side of the lesion

82
Q

Define intention tremor.

A

Inappropriate loss of fine motor control, particularly when the animal intends to eat or nurse

83
Q

Define a tremor.

A

Small and rapid altering contractions of agonist and antagonist muscle groups that occur at rest or during movement

84
Q

Define weakness.

A

Loss of muscle strength

85
Q

Define paresis.

A

Partial loss of neural control of muscles

86
Q

Define paralysis.

A

Complete loss of neural control of the muscles

87
Q

Define proprioception.

A

Awareness of the location of the limb in space

88
Q

Define circumduction.

A

Movement of a limb such that the distal portion describes a circle, with the proximal portion being fixed

89
Q

Define ataxia.

A

Abnormal gait characterized by incoordination but without spasticity, weakness, or involuntary movements

90
Q

What causes atexia?

A

Lesions in the proprioceptive pathways, vestibular system, or cerebellum

91
Q

Define dysmetria.

A

Movements that are too short or too long

92
Q

Define hypermetria.

A

The exaggerated movements of the limbs during locomotion; goose-stepping

93
Q

If there is a lesion at C1-C5, what deficits will there be? Reflexes present?

A

UMN on all 4 limbs
Spastic paresis of both front and back limbs
Hyperactive to normal reflexes in all 4 limbs

94
Q

If there is a lesion at C6-T2, what deficits will there be? Reflexes present?

A

UMN hindlimbs, LMN front limbs
Spastic paresis of back limbs
Flacid paresis of front limbs
Neurogenic muscular atrophy of front limbs only
Hyperactive to normal reflexes in rear limbs
Hypoactive reflexes in front limbs

95
Q

If there is a lesion at T3-L3, what deficits will there be? Reflexes present?

A
UMN hindlimbs only
Spastic paresis of back limbs
Normal back limbs
No neurogenic muscle atrophy
Hyperactive to normal reflexes in hind limbs
96
Q

If there is a lesion at L4-sacrum, what deficits will there be? Reflexes?

A
LMN hindlimbs only
Flaccid paresis of hind limbs
Normal thoracic limbs
Neurogenic muscular atrophy in hindlimbs
Hyporeflexive in hind limbs
97
Q

What lesion would result in a flaccid bladder that is distended, abnormally large, and atonic urethral sphincter?

A

Sacral lesion S1 and S2

98
Q

What lesion would result in a hypertonic bladder that has increased tone, high pressure, and a hypertonic urethral sphincter?

A

Lesion cranial to S1