Acute mastoiditis Acute mastoiditis is the result of extension of acute otitis media into the mastoid air cells with suppuration and bone necrosis. Common in the preantibiotic era, it is now rare in theWestern world (Fig. 10.1). SYMPTOMS 1 Pain—persistent and throbbing. 2 Otorrhoea—usually creamy and profuse. 3 Increasing deafness. SIGNS 1 Pyrexia. 2 General state—the patient is obviously ill. 3 Tenderness is marked over the mastoid antrum. 4 Swelling in the postauricular region, with obliteration of the sulcus.The pinna is pushed down and forward (Fig. 10.2). 5 Sagging of the meatal roof or posterior wall. 6 The tympanic membrane is either perforated and the ear discharging, or it is red and bulging. If the tympanic membrane is normal, the patient does not have acute mastoiditis. INVESTIGATIONS 1 White blood count—raised neutrophil count. 2 CT scanning shows opacity and air cell coalescence. OCCASIONAL FEATURES OF ACUTE MASTOIDITIS 1 Subperiosteal abscess over the mastoid process. 2 Bezold’s abscess—pus breaks through the mastoid tip and forms an abscess in the neck. 3 Zygomatic mastoiditis—results in swelling over the zygoma. TREATMENT When the diagnosis of acute mastoiditis has been made, do not delay.The patient should be admitted to hospital. 1 Antibiotics should be administered intravenously (i.v).The choice of antibiotic, as always, depends on the sensitivity of the organism. If the organism is not known and there is no pus to culture, start amoxycillin and metronidazole immediately. 2 Cortical mastoidectomy. If there is a subperiosteal abscess or if the response to antibiotics is not rapid and complete, cortical mastoidectomy must be performed.The mastoid is exposed by a postaural incision and the cortex is removed by drilling. All mastoid air cells are then opened, removing pus and granulations. The incision is closed with drainage. The object of this operation is to drain the mastoid antrum and air cells but leave the middle ear, the ossicles and the external meatus untouched. Meningitis CLINICAL FEATURES 1 The patient is unwell. 2 Pyrexia—may only be slight. 3 Neck rigidity. 4 Positive Kernig’s sign. 5 Photophobia. 6 Cerebrospinal fluid (CSF)—lumbar puncture essential unless there is raised intracranial pressure (q.v). (a) Often cloudy. (b) Pressure raised. (c) White cells raised. (d) Protein raised. (e) Chloride lowered. (f) Glucose lowered. (g) Organisms present on culture and Gram stain. TREATMENT 1 Do not give antibiotic until CSF has been obtained for culture and confirmation of diagnosis.Then start penicillin parenterally and intrathecally. 2 Mastoidectomy is necessary if meningitis results from mastoiditis and should not be delayed.The type of operation will be dictated by the extent and nature of the ear disease. Extradural abscess An abscess formed by direct extension either above the tegmen or around the lateral sinus (perisinus abscess). The features of mastoiditis are present and often accentuated. Severe pain is common.The condition may only be recognized at operation. In addition to antibiotics, mastoid surgery is essential to treat the underlying ear disease and drain the abscess. Brain abscess Otogenic brain abscess may occur in the cerebellum or in the temporal lobe of the cerebrum.The two routes by which infection reaches the brain are by direct spread via bone and meninges or via blood vessels, i.e. thrombophlebitis. A brain abscess may develop with great speed or may develop more gradually over a period of months.The effects are produced by: 1 systemic effects of infection, i.e. malaise, pyrexia—which may be absent; 2 raised intracranial pressure, i.e. headache, drowsiness, confusion, impaired consciousness, papilloedema; 3 localizing signs. TEMPORAL LOBE ABSCESS Localizing signs (Fig. 10.3): 1 dysphasia—more common with left-sided abscesses; 2 contralateral upper quadrantic homonymous hemianopia; 3 paralysis—contralateral face and arm, rarely leg; 4 hallucinations of taste and smell. CEREBELLAR ABSCESS Localizing signs: 1 neck stiffness; 2 weakness and loss of tone on same side; 3 ataxia—falling to same side; 4 intention tremor with past-pointing; 5 dysdiadokokinesis; 6 nystagmus—coarse and slow; 7 vertigo—sometimes. DIAGNOSIS OF INTRACRANIAL SEPSIS: 1 Any patient with chronic ear disease who develops pain or headache should be suspected of having intracranial extension. 2 Any patient who has otogenic meningitis, labyrinthitis or lateral sinus thrombosis may also have a brain abscess. 3 Lumbar puncture may be dangerous owing to pressure coning. 4 Neurosurgical advice should be sought at an early stage if intracranial suppuration is suspected. 5 Confirmation and localization of the abscess will require further investigation. Computerized tomography (CT) scanning will demonstrate intracranial abscesses reliably and should always be performed when it is suspected. Magnetic resonance (MR) imaging shows soft-tissue lesions with more detail than CT but gives no bone detail. If in doubt what to do, discuss the problem with a radiologist. TREATMENT It is the brain abscess that will kill the patient, and it is this that must take surgical priority.The abscess should be drained through a burr hole, or excised via a craniotomy and then, if the patient’s condition permits, mastoidectomy should be performed under the same anaesthetic. After pus has been obtained for culture, aggressive therapy with antibiotics is essential, to be amended as necessary when the sensitivity is known. PROGNOSIS The prognosis of brain abscess has improved with the use of antibiotics and modern diagnostic methods but still carries a high mortality; the outlook is better for cerebral abscesses than cerebellar, in which the mortality rate may be 70%. Left untreated, death from brain abscess occurs from pressure coning, rupture into a ventricle or spreading encephalitis. Subdural abscess Subdural abscess more commonly occurs in the frontal region from sinusitis, but may result from ear disease. Focal epilepsy may develop from cortical damage.The prognosis is poor. Labyrinthitis Infection may reach the labyrinth by erosion of a fistula by cholesteatoma. It may rarely arise in acute otitis media. CLINICAL FEATURES 1 Vertigo may be mild in serous labyrinthitis or overwhelming in purulent labyrinthitis. 2 Nausea and vomiting. 3 Nystagmus towards the opposite side. 4 There may be a positive fistula test—pressure on the tragus causes vertigo or eye deviation by inducing movement of the perilymph. 5 There will be profound sensorineural deafness in purulent labyrinthitis. TREATMENT 1 Antibiotics. 2 Mastoidectomy for chronic ear disease. 3 Occasionally, labyrinthine drainage. Lateral sinus thrombosis A perisinus abscess from mastoiditis causes thrombosis of the lateral sinus and ascending cortical thrombo-phlebitis. Septic emboli are given off and metastatic abscesses may occur. The prognosis is poor but improved by early diagnosis and treatment. CLINICAL FEATURES 1 Swinging pyrexia—up to 40°C. 2 Rigors. 3 Polymorph leucocytosis. 4 Positive Tobey–Ayer test—sometimes. Compression of contralateral internal jugular vein Æ rise in CSF pressure. Compression of ipsilateral internal jugular vein Æno rise. 5 Meningeal signs—sometimes. 6 Positive blood cultures, especially if taken during a rigor. 7 Papilloedema—sometimes. 8 Metastatic abscesses—prognosis poor. 9 Cortical signs—facial weakness, hemiparesis. TREATMENT 1 Antibiotics. 2 Mastoidectomy with wide exposure of the lateral sinus and even removal of infected thrombus. Facial paralysis Facial paralysis can result from both acute and chronic otitis media. 1 Acute otitis media—especially in children and especially if the facial nerve canal in the middle ear is dehiscent. It is, however, uncommon. 2 Chronic otitis media—cholesteatoma may erode the bone around the horizontal and vertical parts of the facial nerve, and infection and granulations cause facial paralysis. In the early stages, the patient will complain of dribbling from the corner of the mouth. Clinical examination confirms the diagnosis—it may be difficult to detect if the weakness is minimal. TREATMENT If due to acute otitis media, a full recovery with antibiotic therapy is to be expected. If due to CSOM, mastoidectomy is mandatory, with clearance of disease from around the facial nerve. Remember—a facial palsy occurring in the presence of chronic ear disease is not Bell’s palsy and active treatment is needed if the palsy is not to become permanent. Do not give steroids. Petrositis Very rarely, infection may spread to the petrous apex and involve the VIth cranial nerve. CLINICAL FEATURES (GRADENIGO’S SYNDROME): 1 Diplopia from lateral rectus palsy. 2 Trigeminal pain. 3 Evidence of middle-ear infection. TREATMENT 1 Antibiotics. 2 Mastoidectomy with drainage of the apical cells.