Ear and Eye (ENT 2) Flashcards
What are the four categories of dizziness?
Vertigo
Presyncope
Disequilibrium
Light headedness
What is vertgio? How may this be described?
Imbalance of tonic vestibular signal
False sense of motion / spinning sensation
What is disequilibirum?
Symmetric vestibular loss, proprioceptive loss, cerebellar damage
Off balance / wobbly
what is presyncope?
Diffusely diminished blood flow / blood
Feeling of losing consciousness / blacking out
What is psychogenic?
Abnormality in the integration of afferent signal by CNS
Vague sumptoms
Possibly feeling disconnected with the environment
What may cause disequilibrium?
Cerebellar damage
Basal ganglia lesion
Cerebellar damage
What may cause presyncope?
Orthostatic hypotension
Hypoglycaemia
Cardiac arrhythmia
List some peripheral causes of vertigo
Benign paroxsymal positional vertigo (BPPV) Vestibular neuritis Meniere disease Otoscleroris Lavrynthitis
List some central causes of vertigo
Vestibular migraine CV disease Cerebellopontine angle and posterior fossa meningiomas MS Acoustic neuroma
How does BPPV present?
Attacks of sudden rotational vertigo lasting >30s are provoked by head turning
Other otological symptoms rare
How is BPPV diagnosed?
Establish important negatives:
No persistent vertigo
No speech, visual, motor or sensory problems
No tinnitus, headache, ataxia, facial numbness, dysphagia
Hallpike test +ve
What is an acoustic neuroma?
Usually painless benign subarachnoid tumours that cause problems by local pressure, and then behave as SOL
Rare = 1 / 100,000 / year
Where do acoustic neuromas usually arise?
Superior vestibular Schwann cell layer
Sometimes called vestibular schwannoma
How do acoustic neuromas present?
Progressive ipsilatural tinnitus +/- sensorineural deafness (cochlear nerve vompression)
Disequilibrium common
Vertigo rare
Trigeminal compression above tumour may give numb face
What investigations are done for an acoustic neuroma?
MRI for all those with unilateral tinnitus / deafness
Key differential = meningioma
What is the management of an acoustic neuroma?
Surgery is difficult and not often needed eg if elderly
Methods of preserving hearing and facial nerve eg stereotactic radiosurgery
What is tinnitus?
Perception of sound in the ears or head where no external source of the sound exists
How can tinnitis be divided?
Objective (audible to examiner) - rare
Subjective (audible only to pt)
What can cause objective tinnitis?
1) Vascular disorders = Pulsatile vibratory sounds
AV malformations, glomus tumours
2) High output cardiac states = Pulsatile sounds
Pagets, hyperthyroid, anaemia
3) Myoclonus of palatal of stapedius / tensor tympani muscles = audible click
4) Patulous eustachian tube = prolonged opening, causing abnormal sound transmission to ear
What can cause subjective tinnitis?
Most commonly associated with disorders causing sensorineural hearing loss eg presbycusis, noise induced hearing loss, Menieres (unilateral)
Conductive deafness less common eg impacted wax, otosclerosis
Otitis media with effusion Thyroid dysfunction DM MS Acoustic neuroma Anxiety
List some ototoxic drugs?
Cause bilateral tinnitis with associated hearing loss
Cisplatin and aminoglycosides = permanent hearing loss
Aspirin, NSAIDs, quinine, macrolides and loop diuretics are associated with tinnitus and reversible hearing loss
List some aminoglycosides
Gentamicin Tobramycin Plazomicin Streptomycin Neomycin
What is the pathophysiology of tinnitis
Poorly understood
Spontaneous otoacoustic emissions
Altered or increased spontaneous activity of auditory nerve
Inappropriate feedback pathways in auditory-limbic system
What tests can be done for tinnitis?
Audiometry
Tympanogram
MRI for unilateral tinnitus to exclude acoustic neuroma