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Vestibular syndrome - Coggle Diagram

- - - - extension of otitis interna in the brainstem
      - affected animals can have other signs suggestive of inner ear involvement
        
        e.g. Horners and facial nerve paresis
      - consider if animal has central vestibular disease with facial nerve paresis and horners.
      - Diagnosis typically via MRI
      - Treatment consists of antibiotics
        
        preferentially after myringotomy and bacterial cultures
      - Otitis media/interna may require surgical treatment by a bulla osteotomy
  - - - significantly associated with peripheral neuroanatomical localisation
    - - paracute onset of often severe clinical signs
        
        vomiting can be seen in the acute stage of the disease
        
        acute idiopathic facial nerve paralysis
        
        improving clinical signs significantly associated
      - a higher body weight is significantly associated
    - - fluids and nutritional support
      - anti-emetics
      - physiotherapy
      - eye lubrication if facial nerve paresis present
    - - residual head tilt can remain
        
        this is the last neurological deficit to improve
      - recurrent episodes are possible
      - good prognosis
    - - drooping, menace absent, palpebral reflexes absent
      - cosmetic issue, does not affect QoL
      - most will continue to have facial nerve deficits
- - - - ears will be at different heights
    - - this is forebrain disease
      - body often involved
      - ears at same height
    - - but these animals will have no other evidence of vestibular dysfunction
  - - - tight circles
    - - unilateral, asymmetrical
  - - - involuntary
      - rhythmic ocular movement to keep retina fixated on a visual target as the head rotates
    - - occurs spontaneously (spontaneous) or when an abnormal head posture is induced (positional)
    - - not usually pathological
      - slow phase in one direction and a rapid recovery in the opposite direction
      - can be horizontal, rotary or vertical in character
      - Spontaneous /resting
        
        observed when the head is in a normal static position
      - positional
        
        elicited by moving the head into an unusual position
        
        e.g. dorsal extension or placing the animal in dorsal recumbency
    - - if no fast/slow phase can be recognised
        
        the eyes move with an equal velocity in each direction, which resembles the trajectory of a pendulum
      - Congenital in certain cat breeds
        
        siamese
        
        birman
        
        himalayan
      - can be associated with convergent strabismus
      - Manifestation of a congenital abnormality in the visual pathway
        
        larger percentage than normal of optic nerve axons cross the chiasm
        
        should not be seen as a pathological nystagmus or indication for vestibular disease
      - conflicting visual information mapped in central visual pathway
      - occasionally seen the cerebellar disease and visual deficits
  - - - the eye on the affected side deviates ventrally or ventrolaterally when the head is elevated
      - increased exposure of sclera dorsally
      - occurs on the side ipsilateral to the lesion
  - - - Meclozine
      - Maropitant
- - - - common cause of acute vestibular disease
      - paracute onset of non-progressive and focal (often obviously lateralised) clinical signs
        
        can be non-ambulatory
      - if not immediately fatal, very good prognosis with improvement expected in a couple of days
      - 50% of dogs have underlying disease predisposing them to a cerebrovascular accident
        
        Hypertension
        
        Hyperadrenocorticism (cushing)
        
        diabetes mellitus
        
        hypothyroidism
        
        protein losing enteropathy
        
        protein losing nephropathy
        
        coagulation disorder
        
        sepsis
        
        neoplastic emboli
        
        heart disease
        
        Further diagnostics
        
        Recommended
        
        blood pressure reading
        
        interpret with caution as hypertension is a normal physiological response after ischaemic infarct and often have multiple reasons to be hypertensive.
        
        complete blood work
        
        urinalysis
        
        Additional
        
        thoracic and abdominal imaging
        
        coagulation profile
        
        cardiac ultrasound
        
        endocrinology screening
    - - Signs possibly due to damage to adjacent midbrain regions involved in vestibular function
- - - - Horner's syndrome
      - facial and vestibulocochlear nerve run in close proximity
      - facial and sympathetic nerve run through inner ear
  - - - suggestive for brainstem localisation
      - on affected side
      - most often same side as head tilt
      - due to involvement of the UMN pathways to the limbs
    - - depression of consciousness due to disturbance of the ascending reticular activating system
    - - CNs V to XII
    - - may not be reliable as hard to differentiate from rotary nystagmus
    - - CAN RULE IN CENTRAL, BUT CANNOT RULE OUT
      - CATS WITH CENTRAL DISEASE DO NOT ALWAYS DISPLAY THESE ABNORMALITIES/SIGNS
    - - due to involvement of the UMN pathways to the limbs
      - or tetra paresis in combination with ataxia (esp. brainstem)
  - - - titubation
- - - - brainstem
      - cerebellum
- - - - paresis typically not a feature
      - possible crouching close to floor
    - - physiologic nystagmus also absent
      - no spontaneous os positional nystagmus
  - - - metronidazole toxicity
        
        onset of clinical signs can occur as soon as 3d after starting treatment , but also seen following chronic therapy
        
        doses between 30 and >60mg/kg/day have been associated with development of clinical signs
        
        can also occur with recommended dose, esp. if liver dysfunction present.
        
        administration of diazepam demonstrated to fasten recovery
        
        initial dose of 0.43mg/kg IV, followed by 0.43mg/kg orally q8h for 3 days
        
        recovery typically seen in 1-3 days with this
        
        Recovery within 2-3 weeks after discontinuation without the addition of diazepam
        
        Typically results in a forebrain disease in cats
    - - Thiamine deficiency