Fig. 9.1 The ear. A The pinna. B Cross-section of the outer, middle and inner ear.

A B

Fig. 9.2 Structures seen on otoscopic examination of the right ear. A Main structures. B Normal tympanic membrane.

EAR

The history • 173

9

of the VIII nerve or cochlea (Box 9.2). Profound loss before speech

acquisition affects speech development and quality.

Tinnitus

Tinnitus is an awareness of a noise in the absence of an external

stimulus.

Ask about:

• quality of tinnitus: high-pitched, ringing, pulsatile

• intermittent or constant nature

• whether it is unilateral or bilateral

• associated hearing loss or other ear symptoms.

cholesteatoma (an invasive collection of keratinising squamous

epithelium) can form. The chorda tympani nerve runs through

the middle ear carrying taste fibres from the anterior two-thirds

of the tongue; these ‘hitch a ride’ with the facial nerve, which

runs through the mastoid bone in the wall of the middle ear.

Inner ear

The inner ear contains the organs of hearing (cochlea) and balance

(vestibular system). The vibration of the stapes footplate stimulates

fluid within the cochlea. This results in the movement of hair cells

in the cochlea, which are converted to electrical impulses along

the vestibulocochlear nerve (VIII).

The vestibular system helps maintain balance, along with

visual input and proprioception. The vestibular part of the inner

ear contains:

• The lateral, superior and posterior semicircular canals:

these lie at right angles to detect rotational motion of their

fluid (endolymph) in three planes.

• The utricle and the saccule: their hair cells are embedded

in a gel layer containing small crystals (otoliths), which are

subject to gravity and enable detection of head tilt and

linear acceleration.

The history

Common presenting symptoms

Pain and itching

Ask about:

• quality of the pain

• preceding trauma, upper respiratory tract infection (URTI)

• associated symptoms: dysphagia/voice change

(suggesting possible referred pain from a throat lesion).

Otalgia (ear pain) associated with pruritus (itching) is often

due to otitis externa. Acute otitis media is common in children

and otalgia often follows an URTI. Other causes of otalgia are

described in Box 9.1.

Ear discharge

Ask about:

• purulent, mucoid or blood-stained discharge (otorrhoea)

• associated pain.

A purulent discharge can be caused by otitis externa or acute

otitis media with a perforation. A chronic offensive discharge

may be a sign of cholesteatoma.

Blood-stained discharge may suggest the presence of

granulation tissue from infection or can be a result of trauma,

with or without an associated cerebrospinal fluid (CSF) leak.

Hearing loss

Ask about:

• sudden or gradual onset

• precipitating factors: trauma, URTI, noise exposure,

antibiotics

• impact of the hearing loss on the patient’s function.

Hearing loss can be due to disruption in the conduction

mechanism or may have sensorineural causes, such as failure

9.1 Causes and features of earache (otalgia)

Cause Clinical features

Otological

Acute otitis externa Pain worse on touching outer ear, tragus

Swelling of ear canal

Purulent discharge and itching

Acute otitis media Severe pain, red, bulging tympanic

membrane, purulent discharge if tympanic

membrane perforation present

Perichondritis Erythematous, swollen pinna

Trauma Pinna haematoma, pinna laceration,

haemotympanum (blood behind tympanic

membrane); cerebrospinal fluid leak or

facial nerve palsy may be present

Herpes zoster (Ramsay

Hunt syndrome)

Vesicles in ear canal, facial nerve palsy

may be present; vertigo is common

Malignancy Mass in ear canal or on pinna

Non-otological

Tonsillitis

Peritonsillar abscess

Sore throat, tonsil inflammation

Trismus, soft-palate swelling in peritonsillar

abscess

Temporomandibular

joint dysfunction

Tenderness, clicking of joint on jaw opening

Dental disease Toothache, e.g. due to dental abscess

Cervical spine disease Neck pain/tenderness

Cancer of the pharynx

or larynx

Associated sore throat, hoarseness,

dysphagia, weight loss, neck lump

9.2 Causes of hearing loss

Conductivea

• Wax

• Otitis externa

• Middle ear effusion

• Trauma to the tympanic

membrane/ossicles

• Otosclerosis

• Chronic middle ear infection

• Tumours of the middle ear

Sensorineuralb

• Genetic, e.g. Alport’s

syndrome

• Prenatal infection, e.g. rubella

• Birth injury

• Infection:

• Meningitis

• Measles

• Mumps

• Trauma

• Ménière’s disease

• Degenerative (presbyacusis)

• Occupation- or other

noise-induced

• Acoustic neuroma

• Idiopathic

a

Disruption to the mechanical transfer of sound in the outer ear, eardrum or

ossicles. b

Cochlear or central damage.

174 • The ear, nose and throat

• associated headaches, nausea or aura (migraine)

• previous significant head injury; previous URTI.

The most common causes of vertigo include benign paroxysmal

positional vertigo (attributed to debris within the posterior

semicircular canal), vestibular neuritis (also known as vestibular

neuronitis, a viral or postviral inflammatory disorder) and Ménière’s

disease (caused by excess endolymphatic fluid pressure). Other

causes include migraine, cerebral ischaemia, drugs and head

trauma. Discriminating features are described in Box 9.3.

Nystagmus

Nystagmus is an involuntary rhythmic oscillation of the eyes,

which can be horizontal, vertical, rotatory or multidirectional. It

may be continuous or paroxysmal, or evoked by manœuvres

such as gaze or head position. The most common form, ‘jerk

nystagmus’, consists of alternating phases of a slow drift in one

direction with a corrective saccadic ‘jerk’ in the opposite direction.

The direction of the fast jerk is used to define the direction of

nystagmus (Box 9.4). Pendular nystagmus, in which there is

a sinusoidal oscillation without a fast phase, is less common.

Nystagmus may be caused by disorders of the vestibular, visual

or cerebellar pathway.

Tinnitus is usually associated with hearing loss. An acoustic

neuroma (a tumour of the vestibulocochlear nerve, cranial nerve

VIII) needs to be considered in unilateral tinnitus or tinnitus with

an asymmetrical sensorineural hearing loss.

Vertigo

Vertigo is a sensation of movement relative to one’s surroundings.

Rotational movements are most common and patients often have

associated nausea, vomiting and postural or gait instability. Vertigo

can originate peripherally or, less often, centrally (brainstem,