Fig. 9.1 The ear. A The pinna. B Cross-section of the outer, middle and inner ear.
of the VIII nerve or cochlea (Box 9.2). Profound loss before speech
acquisition affects speech development and quality.
Tinnitus is an awareness of a noise in the absence of an external
• 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.
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
• 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
• 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
• purulent, mucoid or blood-stained discharge (otorrhoea)
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.
• precipitating factors: trauma, URTI, noise exposure,
• 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)
Acute otitis externa Pain worse on touching outer ear, tragus
Purulent discharge and itching
Acute otitis media Severe pain, red, bulging tympanic
membrane, purulent discharge if tympanic
Perichondritis Erythematous, swollen pinna
Trauma Pinna haematoma, pinna laceration,
haemotympanum (blood behind tympanic
membrane); cerebrospinal fluid leak or
facial nerve palsy may be present
Vesicles in ear canal, facial nerve palsy
may be present; vertigo is common
Malignancy Mass in ear canal or on pinna
Sore throat, tonsil inflammation
Trismus, soft-palate swelling in peritonsillar
Tenderness, clicking of joint on jaw opening
Dental disease Toothache, e.g. due to dental abscess
Cervical spine disease Neck pain/tenderness
Associated sore throat, hoarseness,
dysphagia, weight loss, neck lump
• Chronic middle ear infection
• Prenatal infection, e.g. rubella
Disruption to the mechanical transfer of sound in the outer ear, eardrum or
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 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
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 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,
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