Examination of the Ear

Hey people...... Just a brief summary of the ear exam!

Testing the Eight Cranial (Acoustic) Nerve

Two components

• Cochlear - afferent fibres subserving hearing , organ of Corti
• Vestibular - afferent fibres subserving balance, begin in utricle and semicircular canals and joins with auditory fibres of facial canal

History

• Noticed by patient or relatives?
• Unilateral hearing loss more common - nerve lesion?
• Gradual or sudden onset?
• History of deafness? Occupational ? Recreational? Exposure to loud noise?
• History of trauma or recurrent ear infections?

Examination

• Look at patient's ear, if patient is wearing hearing aid, remove it.
• Examine pinna :-

-look for scars behind ears

-pull on pinna gently, if tender = external ear disease/temporomandibular joint

-feel for nodes, if present = disease of external auditory meatus (canal)

• Inspect external auditory meatus (canal)

- Canal angulates, thus, to see eardrum, pull the auricle(earlobe) up and backwards before inserting otoscope ( oto = ear)

- Normal eardrum = PEARLY GREY and CONCAVE

- Look for wax or other obstructions and inspect eardrum for inflammation

A Quick Simple Test to test hearing

• Cover opposite auditory meatus with 1 finger, moving this finger as a distraction while you whisper a number in the other ear
• Use same numbers for both ears.
• For high tone, use 68 and low tone, use 100
• Whisper towards the end of expiration to standardize volume and 60cm from ear
• Examiner's larynx should not vibrate if whispering is soft enough

If partial deafness is suspected, Rinne's and Weber's Tests

Rinne's Test : it compares the patients ability to hear a tone conducted via air and bone - the mastoid process.

• normal ear, air conduction (AC) is better than bone conduction (BC) = Rinne Positive
• conductive hearing loss, bone conduction is better than air = Rinne Negative

Weber's Test: it compares bone conduction in both ears. It is most valuable in distinguishing between a true and false Rinne's negative test. It is frequently done post-operatively, to check that the ear is active.

If the sound lateralizes (is louder on one side than the other), it suggests the following:

• an ipsilateral(same side) conductive hearing loss
• a contralateral(opposite site) sensorineural (caused by lesion/disease of inner ear/auditory nerve) hearing loss.

Extra info on weber's test:

http://hemakumar.fastlink.in/pdfs/webertest.pdf