Fifth Stage
E.N.T
Dr. Mushtaq – Lecture 6
1
Vertigo
Definition:
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Illusion of movement
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Disorder of orientation in space
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Disagreeable sensation of movement
Anatomy & physiology of balance
The balance depends on the three integrated inputs:
1- vision 70%
2- proprioceptive inputs / joints, skin & muscles. 15%
3- vestibular system 15%
Vestibular anatomy
bony & membranous labyrinths
2
Sensory epithelial cells
1. The sensory epithelium of the utricle, the
utricular macula
,
2. The sensory epithelium of saccule , the
saccular macula
3. s.c.c
crista ampullaris
Macula &crista
Vestibular sensory cells
Vestibular physiology
Utricular macula signals position of head& linear acceleration
Saccule / exact function is not known
S.c.c. angular rotation
Movement of the cilia to kinocillium side results in a
de polarization of the hair cell, a receptor potential
that in turn releases a transmitter substance that
finally depolarizes (the generator potential) the
afferent fibers that contact it .
Vertiginous pts. can be subdivided into :
1-Positional vertigo
2-Vertigo as an isolated symptom
3-Vertigo with deafness & tinnitus
4-Vertigo with other signs of neurological diseases
3
Positional vertigo
A- benign paroxysmal positional vertigo
- brief, sudden attacks of vertigo precipitated by head movement
- horizontal fatigable nystagmus after latent period
- no other aural symptom
- +ve positional test
- normal hearing assessment
Rx: rest , avoid sudden movement & labrynthine sedatives //cinnirizine
B- disequilibrium of ageing
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Degenerative changes in the maculae & cristae
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Cervical spondylosis can exacerbate the symptoms
C- Malignant positional vertigo
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Coarse variable nystagmus , no latent period
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Non-fatigable
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e,g; disseminated sclerosis
2- Vertigo as an isolated vertigo
A. Vestibular neuronitis
* frequently preceded by viral infection
* severe vertigo without deafness or tinnitus
* caloric test >>canal paresis on the affected ear
Rx: labr. Sedatives
B- drugs:
1) aminoglycosides e,g; streptomycin, gentamycin.
4
2) metronidazole
3) ethinyl oestrodiol
4) anti-hypertention
C- miscellaneous
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Anaemia
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Hypotention
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D.M.
3-vertigo with deafness & tinnitus
A- Meniere`s disease
* unknown aetiology
* theoretically, an expantion of the endolymphatic compartment >>>
increasing endolymphatic Pr. >>> decreasing the mobility of the basilar
membrane >>> hearing difficulty & tinnitus.
same changes in the vestibular apparatus >>> vestibular dysfunction
Clinical features:
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Episodes of vertigo + tinnitus & progressive sensorineural deafness
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5
th
decade
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Last for 1-24h
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Nausea & vomiting
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Normal between attacks
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Vertiginous symptoms improve although hearing tends to deteriorate
Investigations :
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Otoscopical ex >>> normal
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P.T.A >>> fluctuating SNHL
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Caloric test >>> canal pariesis
Treatment :
Medical :
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reduce salt & fluid intake
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reassurance
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vestibular sedative / cinnirizine
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vasodilator / betaserc
5
Surgical:
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Decompression of the endolymphatic sac
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Vestibular n. section
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Labyrinthectomy
B. Labyrinthitis: otorrhoea & H . loss
C. Acoustic neuroma: unilateral hearing loss & tinnitus
D. Syphilis
E. Labyrinthine trauma
F. Miscellaneous conditions: wax , eust.dysf. om
4-vertigo + signs of neurological disease
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Neoplasm involving brain stem ,cerebellum, or mid brain
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Posterior inferior cerebellar artery thrombosis
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Vertibrobasilar insufficency
Thank You,