• Ask the patient, ‘Where do you hear the sound?’

• Record which side Weber’s test lateralises to if not

central.

In a patient with normal hearing, the noise is heard in the

middle, or equally in both ears.

In conductive hearing loss the sound is heard louder in the

affected ear. In unilateral sensorineural hearing loss it is heard

louder in the unaffected ear. If there is symmetrical hearing loss

it will be heard in the middle. Fig. 9.8 Weber’s test.

A B

Fig. 9.9 Rinne’s test. A Testing bone conduction. B Testing air conduction.

178 • The ear, nose and throat

nystagmus may occur. This assesses for gaze nystagmus

and smooth pursuit.

• If any oscillations are present, note:

• whether they are horizontal, vertical or rotatory

• which direction of gaze causes the most marked

nystagmus

• in which direction the fast phase of jerk nystagmus

occurs.

Discriminating characteristics of nystagmus are detailed in

Box 9.4.

Dix–Hallpike positional test

Examination sequence

• Ask the patient to sit upright, close to the end of the

couch.

• Turn the patient’s head 45 degrees to one side (Fig. 9.10A).

• Rapidly lower the patient backwards so that their head is

now 30 degrees below the horizontal. Keep supporting the

head and ask the patient to keep their eyes open, even if

they feel dizzy (Fig. 9.10B).

• Observe the eyes for nystagmus. If it is present, note

latency (time to onset), direction, duration and fatigue

(decrease on repeated manœuvres).

• Repeat the test, turning the patient’s head to the other

side (Fig. 9.10C).

Normal patients have no nystagmus or symptoms of vertigo.

A positive Dix–Hallpike manœuvre is diagnostic for benign

paroxysmal positional vertigo. There is a delay of 5–20 seconds

before the patient experiences vertigo and before rotatory jerk

nystagmus towards the lower ear (geotropic) occurs; this lasts for

less than 30 seconds. The response fatigues on repeated testing

due to adaptation. Immediate nystagmus without adaptation,

and not necessarily with associated vertigo, can be caused by

central pathology.

Head impulse test (or head thrust test)

Examination sequence

• Sit opposite the patient and ask them to focus on a target

(usually your nose).

test is more sensitive and therefore the tuning fork will lateralise

to the affected ear in conductive hearing loss before Rinne’s

test becomes abnormal (negative). In sensorineural hearing loss,

Rinne’s test will be positive, as air conduction is better than

bone conduction.

Tuning fork test findings are summarised in Box 9.5.

Testing vestibular function

Testing for nystagmus

Examination sequence

• Patients should be tested with spectacles or contact

lenses for best corrected vision.

• With the patient seated, ask them to fixate on a stationary

target in a neutral gaze position and observe for

spontaneous nystagmus.

• Hold your finger an arm’s length away, level with the

patient’s eye, and ask the patient to focus on and follow

the tip of your finger. Slowly move your finger from side to

side and up and down and observe the eyes for any

oscillations, avoiding extremes of gaze where physiological

9.5 Tuning fork tests

Weber test Rinne test

Bilateral normal hearing Central AC>BC, bilateral

Bilateral symmetrical

sensorineural loss

Central AC>BC, bilateral

Unilateral or asymmetrical

sensorineural loss LEFT

Louder right AC>BC, bilaterala

Unilateral conductive loss LEFT Louder left BC>AC, left

AC>BC, right

Bilateral conductive loss

(worse on LEFT)

Louder left BC>AC, bilateral

a

Patients with a severe sensorineural loss may have BC>AC due to BC crossing

to the other better-hearing cochlea that is not being tested (false-negative

Rinne test).

AC, air conduction; BC, bone conduction.

A

120

degrees

B C

120

degrees

Fig. 9.10 Dix–Hallpike position test. The examiner looks for nystagmus (usually accompanied by vertigo). Both nystagmus and vertigo typically decrease

(fatigue) on repeat testing. See text for details.

Anatomy and physiology • 179

9

If imbalance or vertigo with nystagmus is induced, it suggests an

abnormal communication between the middle ear and vestibular

system (such as erosion due to cholesteatoma).

Investigations

Initial investigations in ear disease are summarised in Box 9.6

and Figs 9.11–9.12.

• Hold the patient’s head, placing a hand on each side of it.

• Rapidly turn the patient’s head to one side in the

horizontal plane (roughly 15 degrees) and watch for any

corrective movement of the eyes. Repeat, turning the head

towards the other side. The eyes remain fixed on the

examiner’s nose in a normal test. When the head is turned

towards the affected side the eyes move with the head

and there is then a corrective saccade.

This is a test of the vestibulo-ocular reflex. The presence of a

corrective saccade is a positive test and indicates a deficiency

in the vestibulo-ocular reflex. It is useful to identify unilateral

peripheral vestibular hypofunction. You must be careful when

performing this test in patients with neck problems because of

the rapid movements of the head.

Unterberger’s test

Examination sequence

• Ask the patient to march on the spot with their eyes

closed. The patient will rotate to the side of the damaged

labyrinth.

Fistula test

Examination sequence

• Compress the tragus repeatedly against the external

auditory meatus to occlude it.

9.6 Investigations in ear disease

Investigation Indication/comment

Swab from external auditory meatus Otorrhoea, such as in otitis externa or otitis media with a tympanic membrane perforation; microscopy and

culture can help guide treatment

Magnetic resonance imaging Acoustic neuroma (Fig. 9.11)

Asymmetrical sensorineural hearing loss or unilateral tinnitus

Audiometry Hearing loss

A single-frequency tone at different noise levels is presented to each ear in turn through headphones in a

soundproof booth. The intensity of sound is reduced in 10-decibel steps until patients can no longer hear it.

The hearing threshold is the quietest sound they can hear. Audiograms display air and bone conduction

thresholds, and conductive and sensorineural hearing loss can therefore be differentiated (Fig. 9.12)

Impedance audiometry (tympanometry) Conductive hearing loss (e.g. otitis media with effusion, ossicular discontinuity, otosclerosis)

Eustachian tube dysfunction

The compliance of the tympanic membrane is measured during changes in pressure in the ear canal;

compliance should be maximal at atmospheric pressure

Vestibular testing: Unilateral vestibular hypofunction

Caloric tests Water at 30°C and then 44°C is irrigated into the external ear canal. Electronystagmography records

nystagmus. The response is reduced in vestibular hypofunction

Posturography Reveals whether patients rely on vision or proprioception more than usual

Usually reserved for specialist balance clinics

Fig. 9.11 Magnetic resonance image showing a right acoustic

neuroma (arrow).

NOSE AND SINUSES

Anatomy and physiology

The external nose consists of two nasal bones that provide support

and stability to the nose. The nasal bones articulate with each

other and with bones of the face: the frontal bone, the ethmoid

bone and the maxilla. The nasal bones also attach to the nasal

septum and the paired upper lateral cartilages of the nose. There

are two further paired cartilages, the lower lateral cartilages, which

form the nasal tip. Internally the nasal septum, which is bone

posteriorly and cartilage anteriorly, separates the nose into two

nasal cavities that join posteriorly in the postnasal space. There

are three turbinates on each side of the nose, superior, middle and

inferior, which warm and moisten nasal airflow (Figs 9.13 and 9.14A).

One important function of the nose is olfaction. The olfactory

receptors are situated high in the nose in the olfactory cleft.

Olfactory fibres from the nasal mucosa pass through the cribriform

plate to the olfactory bulb in the anterior cranial fossa.