Tinnitus

Please note that the following is a general guideline/ discussion only. For a full assessment, exclusion of any other underlying cause for your symptoms and an individualised treatment approach, you will need to be seen by a qualified specialist.

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DEFINITION

an abnormal perception of a rhythmic sound in the ear in the absence of external stimuli

EPIDEMIOLOGY

Incidence → affects 17% of the population

Age → prevalence is highest in 40-70 yo

Sex → M=F

CLASSIFICATION

Objective: heard by the patient and the examiner

Subjective: Only heard by the patient (most common type) This however could be due to sinister pathology not just due to psychological reasons.

PATHOPHYSIOLOGY

Objective-A real sound generated in body is conducted to cochlea. This could is heard by the patient and the examiner

1) Pulsatile Type: This could be due to turbulent blood flow through constricted vessels e.g. glomus (vascular tumour), AVM, aneurysm, carotid bruits

2) clicking type: This could be due toTMJ clicks, palatal myoclonus, ME muscle contraction

3) Humming type: This due to a patulous (over open) eustachian tube. This can cause excessive transmission of sounds from nasopharynx to the ear. This can cause autophonia, hearing own breathing, roaring tinnitus

 Subjective-A phantom sensation not heard by the examiner. This could be due to 

Neurological pathology such as Acoustic Neuroma, Multiple Sclerosis, Migraine, head injury

Otological pathology such as cholesteotoma, meniere's, hearing loss of various types, Eustachian tube dysfunction 

Metabolic causes such as hyper thyroidism, vitamin mineral deficiencies, poor diabetic control

Certain medications ie NSAIDS, 

Psychological: such as anxiety, depression (generally anxiety makes tinnitus worse rather than cause tinnitus) 

HISTORY AND EXAMINATION 

Usually bilateral, symmetrical tinnitus is beinign and may well be due to age related hearing loss. In unilateral other pathologies must be excluded. 

History should be directed to identify if tinnitus is could be a subjective or an objective form. 

Objective is usually click or pulsate tinnitus. If this is the case one must look for a potential cause as listed above. Bruits, vascular malformation in the middle ear must be excluded. 

If constant tinnitus, history should be taken to identify if it has any known

pattern. i.e. ear discharge and tinnitus may be due to middle ear pathology such

as cholesteotoma. Rumbling tinnitus followed by vertigo may be due to

meniere's. Unilateral hearing loss and tinnitus could be due to acoustic neuroma. Sinusitis and tinnitus may be due to eustachian tube dysfunction. 

Diabetes, metabolic issues may also induce tinnitus. 

INVESTIGATIONS

Therefore clinical suspicion will direct investigations

i.e. blood work up for metabolic causes

MRI and MRA if vascular pulsatile tinnitus 

Doppler neck if bruits or thrills 

MRI scan-if acoustic neuroma is suspected

CT fine cut temporal bones-if cholesteotoma

Audiometry if hearing loss is suspected. 

CT sinus if sinusitis is suspected

TREATMENT

If a definitive cause is identified (least common) need to treat that. This may be medical treatment such as treating sinusitis-eustacian tube dysfunction or surgery depending on the pathology. If no cause is identified (most common)  following measures can be taken.

Avoidance of precipitants

stimulants → caffeine, smoking and alcohol

loud noise → occupational and recreational

certain drugs → aspirin and NSAIDs

Medications

Rx insomnia, anxiety, and depression

combination of medication and/or psychotherapy

no medications have been found to be particularly effective

Masking and hearing aids

White noise → from a radio or a home masking machine

HAs

Hearing Aids – amplify ambient noise which masks tinnitus

Tinnitus Maskers – deliver narrow band noise, centred around pitch of tinnitus, at low intensity

Combined HA and masker

Tinnitus retraining therapy (Done by our Visiting Audiologist) 

technique of habituation using a combination of masking with low level broadband noise and counselling to achieve habituation of the reaction to tinnitus and the perception of the tinnitus signal itself

1. Removal of the negative association attached to tinnitus perception.

Signals that induce fear or indicate danger cannot and should not be habituated. We must not habituate sounds that provide warning signals. The decreased negative association of tinnitus is achieved through directive counseling. The patient is taught the basic function of the auditory system and the brain relative to tinnitus. Decreasing the reaction of the autonomic nervous system is a primary goal of the therapy.

2. Preservation of tinnitus detection, but not necessarily perception, during treatment. 

The second condition is less obvious but equally important. In order to retrain the neuronal networks, it is imperative that tinnitus be detected. Retraining cannot be achieved for a signal that is masked or undetectable. Thus, for habituation oriented therapy, masking of tinnitus excessively is counterproductive.

Low level, broad band sound is used to facilitate tinnitus habituation. Silence actually enhances tinnitus and patients undergoing TRT are advised to avoid silence. They should immerse themselves in a low level, emotionally neutral sound environment. TRT involves use of in-the-ear sound generators to provide this neutral sound environment. The sound generators are operated at a low enough level that the tinnitus can still be detected. Broad band sound contains all frequencies which gently stimulate the nerve cells in the subconscious networks allowing them to be more easily reprogrammed, or habituated, to no longer notice the tinnitus.