Neurological localization Flashcards
Is it a neurological patient?
How can you tell? (4)
- anamnesis (main complaint, onset, course, pain, previous/related illnesses)
- general clinical examination
- orthoaedic/ophthalmological/dermatological examinations
- neurological examination
Once we have established its a neuro case, we wanna localize it. What are the options for where we could localize a lesion to?
Brain:
* forebrain
* cerebellum
* brainstem
Spinal cord:
* C1-C5
* C6-Th2
* Th3-L3
* L4-S3
PNS:
* peripheral cranial nerves
* peripheral cranial nerves
* nerve roots
* spinal nerves
* neuromuscular synapse
* muscles
Vestibular:
* peripheral (inner ear)
* central (cerebellum, brainstem)
3-4 important q’s for localization (flowchart)
- Is there monoparesis?
- Generally decreased spinal reflexes?
- CN deficit?
- Vestibular signs?
4 exception to your typical localization rules.
- Unilateral spinal cord damage may occur in a patient with monoparesis! (usually with monoparesis, its related to the PNS)
- Some patients with diffuse or multifocal spinal cord injury may have impaired reflexes in all limbs! (usually decreased reflexes in all limbs indicates PNS issue)
- Cranial nerve deficits can be caused by extracranial (peripheral) nerve disease! (usually CN deficit indicates brain lesion)
- Cranial nerve deficits may coexist with generally weakened spinal reflexes (e.g. polyneuropathy, hypothyroidism).
FOREBRAIN lesion signs,
mental status
CN
posture/gait
postural reactions
spinal reflexes
muscle tone
sensitivity
other findings
Cerebellum lesion signs,
mental status
CN
posture/gait
postural reactions
spinal reflexes
muscle tone
sensitivity
other findings
Brainstem lesion signs,
mental status
CN
posture/gait
postural reactions
spinal reflexes
muscle tone
sensitivity
other findings
tetraparesis with
* normal/increased reflexes in the front limbs
* normal/increased reflexes in the hind limbs
C1-C5
tetraparesis with
* decreased/absent reflexes in the front limbs
* normal/increased reflexes in the hind limbs
C6-Th2
paraparesis with
* normal/increased reflexes in the
hind limbs
Th3-L3
paraparesis with
decreased/absent reflexes in the
hind limbs
L4-S3
PERIPHERAL NERVOUS SYSTEM (PNS) involves? (5)
Clinical signs? (5)
peripheral cranial nerves
nerve roots
spinal nerves
neuromuscular synapse
muscle
Clinical signs:
* monoparesis, tetraparesis
* decreased/absent spinal reflexes in one or all limbs
* proprioceptive positioning deficit
* decreased muscle tone
* NB! There may be a CN deficit! (this is one of those 4 exceptions)
How to differentiate peripheral vestibular problem from central vestibular problem? (5)
If disoriented, indicates peripheral.
If stupor, indicates central.
In peripheral, facial nerve involvement due to anatomy. Central may involve way more CNs.
Vertical nystagmus only in central!
Paresis can be in central, not in peripheral.
Postural reactions may have deficit in central but not in peripheral.
“TRÜFFEL”, French bulldog, 7.y.
* 5 days of movement problems, started
suddenly, stumbles with front limbs
* restless, can’t find a comfortable position
* painful
localize
C1-C5 (due to disc prolapse)
“ROXANNE”, mixed, 9.y.
* a couple of weeks ago seemed painful for a short while when touched
* 5 days ago, hind limbs became weaker, hind legs were “drifting”
* difficult to take position when urinating/ defecating
localize
Th3-L3 (due to disc disease)
“LANCELOT”, bernese mountain dog, 5.y
* ran from yard to room, tripped on the stairs
* doesn`t get up
* does not seem painful
localize
C6-Th2 (due to fibrocartilaginous embolism, only first few hours painful then generally not painful)
Describe FCE.
Canine fibrocartilaginous embolism (FCE) causes acute death of part of the spinal cord due to the sudden blockage of a blood vessel by a small piece of fibrocartilage, likely originating from an intervertebral disc. This blockage disrupts blood flow, leading to spinal cord damage and resulting in sudden, non-progressive weakness or paralysis, typically in the hind limbs.
FCE primarily affects young to middle-aged large and giant breed dogs, though small breeds can also be affected.
only first few hours painful then generally not painful. affected dogs often show sudden weakness or paralysis without signs of distress.
Diagnosis is typically made through MRI, as there are no definitive blood tests for FCE. While there is no specific treatment, supportive care, physical therapy, and time can lead to varying degrees of recovery, with many dogs regaining function within weeks to months.
“ORANZU”, domestic shorhair, 5.y
* progressive movement difficulty, not jumping, weak hind limbs, painful
* apathetic, sleeps more, intermittent appetite
* outdoor cat
* fever T 39,9
localize
L4-S3
Due to tail sign we can suspect cauda equina region as well.
“VIKI”, golden retriever, 8.y.
* 2 weeks of hind limb lamness
* in the morning moved few steps, from noon not able to stand up
* panting, does not seem painful
* daily on a large garden area, no trauma
* eats raw and defrosted chicken meat, can bury the bones and eat them later
localize
peripheral nervous system
* nerve roots
* spinal nerves
* neuromuscular synapse
* muscles
polyradiculoneuritis in small animals
Polyradiculoneuritis in small animals, often compared to Guillain-Barré syndrome in humans, is an immune-mediated disorder affecting the peripheral nerves and nerve roots.
It commonly presents as acute, progressive weakness that starts in the hind limbs and advances to the front limbs, potentially leading to complete paralysis while leaving sensation intact.
The condition is often linked to an immune response triggered by infections, vaccines, or raccoon bites (in raccoon variant polyradiculoneuritis).
Affected animals may lose reflexes but usually do not experience pain.
Diagnosis is based on clinical signs, nerve conduction studies, and ruling out other neuromuscular diseases.
Treatment involves intensive nursing care, physical therapy, and time, as most dogs gradually recover over weeks to months, though some may have residual weakness.
“CAESAR”, miniature schnauzer, 14.y
1 generalised seizure
menace on left side is decreased
localize
brain, right forebrain (contralateral to decreased menace)
(due to meningioma)
“FRANCIS”, french bulldog, 1,4.a.
* 2 days decreased appetite, today vomiting
* coordination seems worse, drifts to the right
* rhythmic movement of the eyes
* previously ear and skin problems
localize
peripheral vestibular problem (due to left otitis interna or media)
“ITI”, domestic shorthair, 8 m
* from a litter by the stable
* uncoordinated movement since kitten
* no deterioration
* appetite and general condition good
localize
cerebellum
(cerebellar hypoplasia due to pankeukopenia infection during gestation probably, feline distemper)
“CARA”, miniature schnauzer, 1.8.y
* 2 days ago salivation, splashing when drinking water
* 1x regurgitation
* sometimes keeps tongue out of mouth
* apathetic
localize
brainstem
* glossopharyngeal CN IX and/or
* vagus CN X
Because swallowing reflex:
➢ A/E: glossopharyngeal (IX)
❖ brainstem
➢ A/E: vagus nerve (X)
