Otoscopy Flashcards
What is rinnes test? What is rinnes positive?
Rinne’s test
- Place a vibrating 512 Hz tuning fork firmly on the mastoid process (apply pressure to the opposite side of the head to make sure the contact is firm). This tests bone conduction.
- Confirm the patient can hear the sound of the tuning fork and then ask them to tell you when they can no longer hear it.
- When the patient can no longer hear the sound, move the tuning fork in front of the external auditory meatus to test air conduction.
- Ask the patient if they can now hear the sound again. If they can hear the sound, it suggests air conduction is better than bone conduction, which is what would be expected in a healthy individual (this is often confusingly referred to as a “Rinne’s positive” result).
Summary of Rinne’s test results
These results should be assessed in context with the results of Weber’s test before any diagnostic assumptions are made:
Normal result: air conduction > bone conduction (Rinne’s positive)
Sensorineural deafness: air conduction > bone conduction (Rinne’s positive) – due to both air and bone conduction being reduced equally
Conductive deafness: bone conduction > air conduction (Rinne’s negative)
What is Weber’s test?
What is a normal response?
Weber’s test
- Tap a 512Hz tuning fork and place in the midline of the forehead. The tuning fork should be set in motion by striking it on your knee (not the patient’s knee or a table).
- Ask the patient “Where do you hear the sound?”
These results should be assessed in context with the results of Rinne’s test before any diagnostic assumptions are made:
Normal: sound is heard equally in both ears.
Sensorineural deafness: sound is heard louder on the side of the intact ear.
Conductive deafness: sound is heard louder on the side of the affected ear.
A 512Hz tuning fork is used as it gives the best balance between time of decay and tactile vibration. Ideally, you want a tuning fork that has a long period of decay and cannot be detected by vibration sensation.
Explain the difference between conductive vs sensorineural hearing loss
Conductive vs sensorineural hearing loss
Conductive hearing loss occurs when sound is unable to effectively transfer at any point between the outer ear, external auditory canal, tympanic membrane and middle ear (ossicles). Causes of conductive hearing loss include excessive ear wax, otitis externa, otitis media, perforated tympanic membrane and otosclerosis.
Sensorineural hearing loss occurs due to dysfunction of the cochlea and/or vestibulocochlear nerve. Causes of sensorineural hearing loss include increasing age (presbycusis), excessive noise exposure, genetic mutations, viral infections (e.g. cytomegalovirus) and ototoxic agents (e.g. gentamicin).
Name the following deformity and its cause
Cauliflower ear is an irreversible condition that develops as a result of repeated blunt ear trauma. Blunt trauma causes bleeding under the perichondrium of the pinna, stripping away the ear’s cartilage. This cartilage normally relies on the perichondrium for its nutrient supply and as a result, once separated it becomes fibrotic, causing distortion of the ear’s archite
What is the following condition?
Otitis externa
What is the following condition?
pre-malignant (actinic keratoses)
What is the following condition?
malignant (e.g. basal cell carcinoma, squamous cell carcinoma) skin changes.
What is the following condition?
Mastoiditis
Name the following deformity
Anotia: a complete absence of the pinna.
Name the following deformity
Microtia: underdevelopment of the pinna.
Name the following deformity
Low-set ears: the ears are positioned lower on the head than usual. Low-set ears are a feature of several genetic syndromes including Down’s syndrome and Turner’s syndrome.
Name the following condition and describe what you see
Erythema, oedmea and discharge: may suggest otitis externa or otitis media with associated tympanic membrane perforation.
Describe what you see
Healthy tympanic membrane
What is the following clinical sign and what does it indicate?
Bulging of the TM suggests increased middle ear pressure, which is commonly caused by acute otitis media with effusion (there is often an associated visible fluid level).
What is the following clinical sign and what does it indicate?
Retraction of the TM suggests reduced middle ear pressure, which is commonly caused by pharyngotympanic tube dysfunction secondary to upper respiratory tract infections and allergies.
What is the following clinical sign and what does it indicate?
Absence or distortion of the light reflex is associated with otitis media (due to bulging of the TM).
What is the following clinical sign and what does it indicate?
TM perforation.
Causes include infection (e.g. otitis media with effusion), trauma (e.g. diving-related), cholesteatoma and insertion of tympanostomy tubes (also known as grommets).
What is the following clinical sign and what does it indicate?
cholesteatoma and insertion of tympanostomy tubes (also known as grommets).
Cholesteatoma typically causes perforation in the superior part of the TM and there may be visible granulation tissue and discharge in this region.
What is the following clinical sign and what does it indicate?
Scarring of the TM is known as tympanosclerosis and can result in significant conductive hearing loss if it is extensive.
Tympanosclerosis often develops secondary to otitis media or after the insertion of a tympanostomy tube.
