Tinnitus

Question 1

What is tinnitus?

Answer 1

Tinnitus = perception of sound when no external sound is present

Tinnitus also described as sound of silence
=> usually masked with background noises

Objective tinnitus = apparent to the examiner

Subjective tinnitus = only apparent to the patient

*Tinnitus commonly assoc. with hearing loss

Question 2

What are the two types of tinnitus?

Answer 2

Non-pulsatile tinnitus

Pulsatile tinnitus

Question 3

What is non-pulsatile tinnitus?

What conditions are associated with non-pulsatile tinnitus?

Answer 3

=> False perception of sound heard by affected individual (subjective tinnitus)

=> often a buzzing, high pitched tone or clicking & popping noise

Conditions:

1. Noise induced hearing loss
2. Presbycusis
3. Meniere’s disease
4. Head injury
5. Otitis Media
6. Drug related i.e. salicylates, NSAIDs, loop diuretics, quinines, Aminoglycosides

Question 4

What is pulsatile tinnitus?

What condition are associated with pulsatile tinnitus?

Answer 4

=> Sound heard is synchronous with the heart-beat

=> Caused by turbulent blood flow that reaches the cochlear

Vascular causes:

1. Atherosclerosis on the internal carotid artery
2. Vascular malformations i.e. arteriovenous malformations/fistulas
3. Glomus tumour (rare hyper vascular tumours arising from paraganglia cells)

Non-Vascular causes:

1. Paget’s disease
2. Otosclerosis
3. Myoclonus of the middle ear

Question 5

What are the 7 main causes of tinnitus?

Answer 5

1. Idiopathic
2. Meniere’s disease:
   => assoc. with hearing loss, vertigo, tinnitus, sensation of fullness or pressure in one or both ears

3. Otosclerosis:
=> Onset 20-40years
=> Conductive deafness
=> Tinnitus
=> Normal tympanic membrane (10% with flamingo tinge due to hyperaemia)
=> +ve Family hx

4. Sudden onset sensorineural hearing loss (SSNHL):
=> 80% acoustic neuroma 
=> Hearing loss, vertigo, tinnitus
=> Absent corneal reflex
=> Assoc. with Neurofibromatosis type 2

5. Hearing loss:
   => Excessive loud noise
   => Presbycusis

6. Drugs:
=> Aspirin/NSAIDs
=> Aminoglycosides
=> Loop Diuretics
=> Quinines 
=> Salicylates 

7. Impacted ear wax:
   => Obvious on otoscopy

Question 6

What is otosclerosis?

Answer 6

Stapes gets stuck in place and cannot vibrate

No vibration = no sound transmitted/amplified

This is because of an abnormal bony tissue growth in middle ear

Question 7

How is tinnitus investigated?

Answer 7

1. If unilateral tinnitus + assoc. with hearing loss => MRI of the internal auditory canal to exclude acoustic neuroma (first line)
2. Pulsatile tinnitus => MR or CT angiography for underlying vascular cause
3. Audiology assessment to detect underlying hearing loss

Question 8

How is tinnitus managed?

Answer 8

1. Reassurance that tinnitus is common and can adapt to it
   => worrying makes it worse
   => silence makes it worse i.e. at night
2. Treat underlying cause i.e. hypertension, carotid stenosis, side effect of meds
3. CBT for some patients by audiologists => coping strategies and tinnitus retraining therapy (TRT)
   => noise generator can mask tinnitus if interfering sleep
   => Tinnitus support group
4. Hearing aid may improve tinnitus if assoc. with hearing loss