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Complications of Chronic Otitis Media Chunfu Dai Three categories on an anatomic basis Extratemporal extracranial Intratemporal Bezold abscess Subperiosteal abscess Mastoiditis, labyrinthitis, sensorineural hearing loss, petrositis Facial paralysis, cholesteatoma, labyrinthine fistula Intracranial Epidural abscess, lateral sinus thrombosis, otitic hydrocephalus, meningitis, brain abscess, subdural abscess Causes Hyper-function of immune system Strong bacteria Damaged structures Infant, older cholesteatoma Unreasonable interventions Drug resistant, Poor drainage Transmission course Pathways of spread Direct extension of infection to structure (bone erosion) Hemogenous routine (microbiologic an host factors) Bacteria gain access to intracranial through unsealed gap, inner ear Bezold abscess Definition: Erosion the tip of the mastoid bone Infects the soft tissue of the neck, Deep to the sternocleidomastoid muscle Diagnosis Ear infection Mass in the neck Fever, neck stiff, otorrhea CT scan Bezold abscess Treatment Antibiotic Abscess cavity should be evacuated An external drainage should be placed Mastoidectomy Antrum drainage required, via epitympanum to the middle ear Supperiosteal abscess Definition: Bone erosion, via osteitis or necrosis, leads to a dehiscence into the postauricular soft tissue. Diagnosis Fever, pain and otorrhea Followed by appearance of the postauricular mass, displacing the auricle anteriorly CT scan Supperiosteal abscess Managements Antibiotic Drainage, using postauriclar incision After achieving effective drainage of the mastoid infection, the site of suppuration can be addressed Necrotic tissues require debridement Labyrinthitis Classifications Cirvumscribed labyrinthitis (fistula of labyrinth) Serous labyrinthitis Communication of middle ear with perilymphatic space Toxin, inflammatory media Suppurative labyrinthitis Bacteria Fistula of labyrinth Including bone erosion, exposure of the endosteal membrane and a true fistula into the fluid compartment of the inner ear. It occurs in 5-10% of cases with cholesteatoma Lateral semicircular canal is the most common location (90%) Mechanism of bone erosion Osteolysis resorptive osteitis Fistula of labyrinth Diagnosis Vertigo (intermittent or constant) Hearing loss Fistula test (only 50% of patients are positive) CT scan may demonstrate evidence of fistula, however, small fistula can be overlooked Fistula of labyrinth Managements Surgical invervention mastoidectomy Removal cholesteatoma matrix at the primary operation, fistula closed with temporal fascia Leaving cholesteatoma matrix undisturbed. 9-12 months later, second operation is performed. antibiotic Serous labyrinthitis Occurs from inflammation, rather than infection Caused by bacterial toxins, inflammtory mediators Inflammatory cells rather than bacteria are found in the labyrintine fluids Vertigo, sensorineural hearing loss Suppurative labyrinthitis Bacteria infiltrates the fluid space of inner ear Vestibular symptoms Acute phase of inflammation: Vertigo, nausea The phase of central compensation: imbalance or unsteadiness Recovery phase: severe perturbation, patients experiences a brief sensation of vertigo. Suppurative labyrinthitis Symptoms associated with cochlea Permanent sensorineural hearing loss Tinnitus Suppurative labyrinthitis Interventions Antibiotic Address the problem of the underlying COM and cholesteatoma Electrolyte (due to vomiting) Prevention Early and effective treatment of the COM and cholesteatoma Petrous apicitis The most medial and anterior portion of the temporal bone 30% of temporal bones with pneumatization of the petrous apex Proximity to the posterior and middle cranial fossae Petrous apicitis Classic triad (Gradenigo’s syndrome) Deep ear and retroorbital pain (irritation of the trigeminal nerve) Aural discharge Ipsilateral abducents nerve palsy Petrous apicitis Managements Antimicrobials directed against the most likely pathogens. If hearing present in the affected ear, otic capsule should be preserved while effective drainage achieved retrolabyrinthine, infralabyrinthine, infracochlear approachs can gain access to the petrous apex Petrous apicitis Managements The affected ear is dead ear, translabyrinthine or transcochlear approaches afford greater access to the petrous apex Intracranial complications Overview It is less frequently, due to Improved access to medical care and medication Broad spectrum antibiotic Pathways of spread Direct extension of infection to intracranial structure (bone erosion) Hemogenous routine (microbiologic an host factors) Bacteria gain access to intracranial through unsealed gap, inner ear Epidural abscess Epidual space is a potential space between the periosteum and outer dural layer, the tough dura often will limit the spread of infection. diagnosis No specific symptoms and signs to an epidural abscess, Pulsative otic discharge Headache (associated with the size of abscess) CT reveals bone erosion, abscess MRI can detect dural thickening and inflammation Epidural abscess Managements Surgical exploration and drainage Bone overlying the temgen tympani, sigmoid sinus, and posterior fossa dura must be thinned, epidural space should be visualized, non inflamed dura is encountered. Medical treatment Antibiotic Sigmoid sinus thrombosis Pathway . Direct extension of mastoid infection Retrograde thrombosis Antergrade thrombosis Sigmoid sinus thrombosis Diagnosis Clinical presentation: high, spiking fevers, Headache, Intracraninal high pressure active ear disease Acute phase of thrombosis, absence of flow signal in MR venography images Sigmoid sinus thrombosis Managements Surgical exploration Mastoidectomy to expose the sigmoid sinus A needle may be used to aspirate the sinus, if freeflowing blood returns, then no additional surgery is needed. If no blood returns, then open and draining the sinus are indicated. In the face of ongoing septic pulmonary emboli, internal jugular vein ligation can be performed. Sigmoid sinus thrombosis Managements Medical treatment Antibiotics Anticoagulation (in individual cases, in the face of propagating thrombosis) Meningitis Among intracranial complications of COM, meningitis is one of the most common, it account for 50% of the intracranial complications. In COM, bacterial contamination may occur via bone erosion with epidural abscess/granulation formation or retrograde thrombophlebitis of emissary veins. Meningitis Diagnosis Symptoms of COM High fever, headache, vomiting Neck stiffness and altered mental status CT or MRI will document meningeal enhancement Lumbar puncture and examination of the CSF is mandatory (CFS leukocytosis and low glucose, elevated level of protein and lactate, bacteria culture present positive) Meningitis Managements Urgent antibiotic (culture and sensitivity reports from the CSF samples can further direct antibiotic therapy Adjunctive therapy (dexamethasone can reduce the neurologic and auditory squelae of bacterial meningitis Reduce the high intracranial pressure Mastoidectomy (removal lesion and achievement of drainage) Brain abscess 62% of abscesses were located in the tempora lobe and 34% in the cerebellum Direct extension along preformed pathways or perivascular channels is more likely route of infection. The thin bone of tegmen may be more easily violated than the bone overlying the posterior fossa dura, given the increased frequency of temporal lobe versus cerebellar abscess. Brain abscess phases Initial phase: localized microfoci and cerebritis or encephalitis Second phase: expansion and secondary delineation of the abscess Final phase: a dense fibroglial scar (capsule) or rupture. Brain abscess Diagnosis Fever, headache and vomiting. Symptoms and signs are derived from the location and size of abscess MRI may be more sensitive in defining area of cerebritis Brain abscess Temporal abscess Contralateral body paralysis Facial paralysis (central) Mutism Cerebellar abscess Central nystagmus Reduction of muscle tension Ataxia Dysfunction of distance perception Brain abscess Treatments Antibiotic (penetration of the blood-brain barrier should be considered) Steroid is administered to reduce brain swelling, dehydration agent will reduce intracranial pressure. Surgical drainage and excision of abscess required Otologic surgery depends on the patient’s clinical stability