ENT Flashcards
(157 cards)
Which bone directly contacts the Tympanic Membrane?
Malleus
During examination, how may you test hearing?
Gross hearing
Weber’s Test (512Hz): central forehead
Rinner’s Test (512Hz): mastoid process until stopped, then 1cm from external auditory canal
Give 5 differentials for Sensorineural Hearing Loss.
Presbyacusis Noise exposure Meniere's Disease Labyrinthitis Acoustic neuroma Neurological conditions Infections (e.g. meningitis) Medications (loop diuretics; Aminoglycoside antibiotics; Chemotherapy drugs)
Which drugs may cause sensorineural hearing loss?
Loop diuretics
Aminoglycosides
Chemotherapy drugs
Give 5 differentials of conductive hearing loss.
Ear wax Infection (AOM; OE) Effusion Eustachian tube dysfunction Perforated TM Otosclerosis Cholesteatoma Exostoses Tumours
what investigation may be used to examine a patient’s hearing?
Audiometry
How does Audiometry work?
Variety of tones and volumes played via air conduction (headphones) and bone conduction (oscillator).
Recorded on an audiogram which helps differentiate conductive and sensorineural hearing loss
Audiogram charts the volume at which a patient can hear different tones.
Frequency (Hz) on X-axis and Volume (dB) on y-axis
Hearing is tested to find quietest volume patient can hear each frequency.
Note: Best hearing (lowest dB) will be highest on a chart. It is a test of hearing, so dB is placed inversely on the graph.
X = LS air conduction
O = RS air conduction
[ = R sided bone conduction
] = L sided bone conduction
What is the healthy range of hearing shown on an audiogram?
0-20dB
In sensorineural hearing loss, what will an audiogram show?
Both air and bone conduction is greater than 20dB
In conductive hearing loss, what will an audiogram show?
Air conduction readings >20dB thus below normal range line and lower on audiogram
In mixed hearing loss, what will an audiogram show?
Both air conduction and bone conduction will be >20dB however there will be a >15dB difference between the two values
What are the clinical features of Presbyacusis?
Hearing loss: Gradual, Higher pitch sounds lost first; symmetrical
May be associated tinnitus
How is Presbycusis treated?
Supportive: Optimising environment; Hearing aids
or
Surgery: Cochlear implant surgery
What would Audiometry show in Presbycusis?
Age-related hearing loss is a sensorineural hearing loss.
Both air and bone conduction will be reduced thus >20dB and move inferiorly
Will be symmetrical, affecting both ears
What is the definition of Sudden Sensorineural hearing loss?
Hearing loss that is sensorineural <72 hours which is unexplained by other causes
What is the most common cause of Sudden Sensorineural Hearing Loss?
A. Acoustic neuroma
B. Cogan’s syndrome
C. Migraine
D. Idiopathic
D - 90%
What is the audiometry criteria required to establish a diagnosis of sudden sensorineural hearing loss?
> 30dB loss at 3 consecutive frequencies
How is Sudden Sensorineural Hearing Loss managed?
Referral to ENT (24 hours)
+
Steroids: Intra-tympanic or PO
A patient presents with a reduced hearing in their L ear over the past 2 months; there is a feeling of fullness in the ear with some discomfort. They are hearing some popping noises in the ear. Symptoms get worse when walking up hills of flying.
Otoscopy shows nothing abnormal.
What investigations may you wish to undertake?
Tympanometry
Audiometry
Nasopharyngoscopy
CT scan
A patient presents with a reduced hearing in their L ear over the past 2 months; there is a feeling of fullness in the ear with some discomfort. They are hearing some popping noises in the ear. Symptoms get worse when walking up hills of flying.
Otoscopy shows nothing abnormal.
Tympanometry shows a peak admittance with negative ear canal pressures.
What is your diagnosis?
Eustachian Tube Dysfunction
A patient presents with a reduced hearing in their L ear over the past 2 months; there is a feeling of fullness in the ear with some discomfort. They are hearing some popping noises in the ear. Symptoms get worse when walking up hills of flying.
Otoscopy shows nothing abnormal.
Tympanometry shows a peak admittance with negative ear canal pressures.
What is your management?
Supportive: Watch and wait; Valsalva manoeuvre; Decongestant nasal sprays; Otovent
±
Surgery: Tx cause; Grommets (tiny tubes into TM); Balloon dilation Eustachian tuboplasty
How is otosclerosis inherited?
Autosomal dominant
What is the pathophysiology involved in otosclerosis?
Middle ear bones undergo sclerosis e.g. stapes which attaches to oval window (fenestra ovalis) of cochlea thus reduced sound transmission
This is a form of conductive hearing loss
What is the epidemiology of Otosclerosis?
Female
<40