Otoscopy and tuning fork tests

Question 1

What is otoscopy?

Answer 1

The examination of the pinna, ear canal and tympanic membrane through the use of an otoscopy

Question 2

What is the purpose of otoscopy?

Answer 2

To ensure that the ear canals are free of any obvious obstructions that would hinder further audiological testing or intervention

Question 3

Why is it important to look for signs of surgical scarring during otoscopy?

Answer 3

This may affect how you take an impression for a hearing aid

Question 4

How do you prepare the patient before otoscopy?

Answer 4

-Ask if the patient has any ear-related symptoms such as discomfort, pain or ear discharge, is currently being treated for any ear-related problems or has previously has surgery involving their ears
-Explain procedure to the patient and tell them to report any pain or discomfort they fell
-Obtain verbal informed consent
-Start with the ear least likely to have any abnormalities

Question 5

What is the onward referral criteria for otoscopy?

Answer 5

1. Complete or partial obstruction of the external auditory canal
2. Abnormal appearance of the outer ear and/ or the eardrum

Question 6

What is the safest position to do otoscopy in?

Answer 6

-Patient and audiologist seated
-Otoscopy braced securely against the patient’s head by the examiner’s pinky finger
-Manipulation of pinna appropriate

Question 7

What are signs of a healthy tympanic membrane?

Answer 7

-Light reflex (cone of light) at 7 o’clock in the left ear and 5 o’clock in the right ear
-Pearly grey in colour, shiny and translucent
-No bulging or retraction
-Smooth in consistency
-Short process, malleus and umbo visible
-Intact with no lesions, blood or holes

Question 8

Describe this otoscopy result

Answer 8

Normal otoscopy in both left and right ear

Question 9

Describe this otoscopy result

Answer 9

Occluding ear wax (cerumen) in both left and right ear

Question 10

Describe this otoscopy result

Answer 10

Schwartz sign (characteristically reddish discoloration) in both right and left ear- sign of otosclerosis

Question 11

Describe this otoscopy result

Answer 11

-Tympanic membrane perforation in both the left and right ear
-In the right ear the edges are quite smooth- suggests it could have been there a while
-No active infection

Question 12

Describe this otoscopy result

Answer 12

Normal for both right and left ear

Question 13

Describe this otoscopy result

Answer 13

Normal right ear, glomus tumour in the left ear

Question 14

Describe this otoscopy result

Answer 14

Normal right ear, potential fluid build up in the left ear suggests otitis media with effusion

Question 15

Describe this otoscopy result

Answer 15

Normal right ear, no otoscopy could be carried out in the left ear due to abnormal ear canal and external ear (caused by radical mastoidectomy)

Question 16

What are tuning fork tests?

Answer 16

-Tuning forks provide very basic information about the probable presence or absence of a significant conductive element to the hearing loss

Question 17

According to the BSA recommended procedure what frequency should the tuning fork elicit and why?

Answer 17

-516 Hz
-At this frequency the tone does not fade too quickly, produces limited overtones and is not vibrotactile (you can’t feel the vibration without the sound)

Question 18

What is the correct method for striking the tuning fork?

Answer 18

-The tuning fork must include a footplate and there should be no damage or chips to the tines
-Hold the tuning fork by its stem and strike one side of the tines, two thirds along the tine from the base on a padded surface, your elbow or ball of hand

Question 19

What are the names of the two tuning fork tests?

Answer 19

The Weber Test and The Rinne Test

Question 20

What is the procedure for the Weber test?

Answer 20

1. Strike the tuning fork and place it on the patient’s midline
2. Place the other hand gently on the patient’s head to ensure enough counter-pressure is applied
3. Hold in place for 4 seconds
4. Ask the patient where the tone is heard (both ears, centrally in the head, or towards the left or right)

Question 21

For the Weber test, what can be interpreted if the patient hears the tone:
1. Centrally
2. In one ear

Answer 21

1. Symmetrical hearing or symmetrical hearing loss
2. Asymmetrical sensorineural hearing loss (sound heard in the better ear), asymmetrical conductive hearing loss (sound heard in the poorer ear)

Question 22

What is the procedure for the Rinne test?

Answer 22

1. Start with the ear which the Weber has lateralised to (if appropriate)
2. Strike the tuning fork and hold the tines approximately 25mm from the ear canal entrance in position for 2 seconds
3. Press the footplate firmly against the mastoid
4. Place your other hand on the opposite side of the patient’s head to ensure enough counter-pressure is applied
5. Hold the tuning fork in place for another 2 seconds
6. Ask the patient whether the tone is louder next to the ear or behind the ear

Question 23

What can be interpreted from the Rinne test if the patient hears the tone louder:
1. Next to the ear canal
2. Behind the ear

Answer 23

1. Air conduction is better- indicates either normal hearing or a sensorineural hearing loss (Rinne positive result)
2. Bone conduction is better- indicates a significant conductive element to the hearing loss (Rinne negative result)

Question 24

What are the problems with the Weber test?

Answer 24

-The Weber test can determine a difference of 5dB between the ears in terms of bone conduction thresholds
-This test is complicated by the presence of a unilateral or asymmetrical conductive hearing loss (the tone will able to be heard on the conductive side or the side with the greater conductive loss)
-Therefore it is prone to error

Question 25

What are the problems with the Rinne test?

Answer 25

-The Rinne test is able to distinguish a conductive hearing loss with an air-bone gap of 17.5 dB- 30 dB
-It has a limited use in detecting mild conductive hearing loss or mixed hearing loss with an air-bone gap of less than 17.5 dB
-False Rinne test negative results occur when the bone conduction transmits through the skull to the opposite ear and is detected through cross hearing by the better cochlea
-This occurs with a severe sensorineural hearing loss on the test side

Question 26

What does the following tuning fork test result suggest?
Weber: Lateralised to the right
Rinne: Positive bilaterally

Answer 26

Weber: Conductive hearing loss on the right side or left-sided sensorineural hearing loss
Rinne: Air conduction surpasses bone conduction- rules out conductive hearing loss

Result: Left-sided sensorineural hearing loss

Question 27

What does the following tuning fork test result suggest?
Weber: Lateralised to the right
Rinne: Negative on the right

Answer 27

Weber: Conductive hearing loss on the right side or left-sided sensorineural hearing loss
Rinne: Air conduction inferior on the right side

Result: Conductive hearing loss on the right side

Question 28

What does the following tuning fork test result suggest?
Weber: No lateralisation
Rinne: Positive bilaterally

Answer 28

Weber: Normal bilateral hearing or bilateral conductive or sensorineural hearing loss
Rinne: Air conduction surpasses bone conduction on both sides

Result: Normal hearing or bilaterally equal sensorineural hearing loss

Question 29

What does the following tuning fork test result suggest?
Weber: No lateralisation
Rinne: Negative bilaterally

Answer 29

Weber: Normal bilateral hearing or bilateral conductive or sensorineural hearing loss
Rinne: Bone conduction surpasses air conduction on both sides

Result: Symmetrical conductive hearing loss

Question 30

What is an example of a case where tuning fork tests become much more difficult to interpret?

Answer 30

Mixed hearing loss

Question 31

Name the red flags that should be asked during history taking

Answer 31

1. Sudden (72 hours) or rapid (90 days) hearing deterioration
2. Fluctuating hearing loss
3. Facial numbness
4. Otalgia
5. Discharge
6. Hyperacusis
7. Tinnitus (with follow up q’s)
8. Vertigo
9. Difficulties with sound processing
10. History of noise exposure
11. Previous otological history including ear infections and surgery