When things go wrong in the nervous system and general exam

Question 1

Types of nerve system damage or dysfunction

Answer 1

Neuronal/nerve damage can be temporary or permanent
Permanent: injury or tumors
Temporary- inflammation, pressure, transient lack of oxygen
Clinical signs reflect the disease process and part of the nervous system affected

Question 2

Signs fall in general catagories

Answer 2

Loss of function: seen if damage to the nerves or the nerve cell bodies which are located close to where the nerve enters the spinal cord
Hyperreflexia: typically seen in intact reflex arcs caudal to the injury
Discharge- electrical bursts in the brain that may result in seizures. Can be acquired or due to genetic problems e.g. absence of a receptor for an inhibitory neurotransmitter.

Question 3

Why do a neuro exam

Answer 3

The neurological exam allows us to
Localize the lesion
Determine its cause

Question 4

Goal of the neuro exam

Answer 4

Localize lesion and make diagnosis
Job of the vet
Information from the history and neurological exam will narrow down the possible location of the lesion
Knowledge of the physiology and anatomy of the nervous system is critical
Further testing such as CSF tap, myelogram, CT, or MRI can provide a specific diagnosis
It is unlikely that you will be performing the neurological exam on your own, however, you will assist and need to understand whats going on

Question 5

History part of neuro exam

Answer 5

The primary complaint- behavioural, seizures, gait abnormalities, head tilt, abnormal eye movements
Species and breed
Age/sex
Housing/management
Onset and progression
Behavioural changes
Description of onset and progression
Acute→ sudden onset of clinical signs→ trauma, vascular accident, toxins, infection
Chronic→ slow onset of clinical signs→ neoplasia and degenerative conditions
Progressive vs. nonprogressive- progression means that the clinical signs have worsened since they first appeared

Question 6

Observation part of neuro exam

Answer 6

Mentation- alert, depressed, stupor, coma
Alert- normal animals, aware and engaged with its surroundings
Lethargic/depressed- conscious but inactive, may sleep when undisturbed
Stuporous- tends to sleep when undisturbed and stimuli like touch and sound may not rouse them. Usually response to painful stimuli.
Comatose- deeply unconscious, cannot be aroused

Question 7

Palpation of neuro exam

Answer 7

Trauma/pain
Push on each vertebrae to test for pain response
Asymmetry to muscle
Muscles atrophy rapidly and severely with loss of nerve supply

Question 8

Posture of nueo exam

Answer 8

Head tilt- vestibular signs
Fixed head and neck position- common in animals with neck pain
Wide-based stance common in many neurological diseases
Can see rigidity of limbs (full extensions) with certain brain diseases

Question 9

What to check in neuro exam

Answer 9

History
Observation-mentation
Palpation
Postural and gait
Reflexes
Cranial nerve exam