Transcript Otology Seminar Temporal Bone Osteomyelitis

Yi-Tsen, Lin
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Introduction
Pathophysiology
Pathogens
Clinical manifestations
Laboratory studies
Imaging
Medical treatment
Surgical treatment
Prognosis
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1959, Meltzer and Keleman:
 Bacillus pyocyaneus osteomyelitis of temporal
bone in a diabetic patient
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1968, Chandler:
 Malignant otitis externa
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Skull base osteomyelitis
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Malignant otitis externa
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Chronic otitis media
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Osteoradionecrosis
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Soft tissue infection of the ear canal
Spread via the fissures of Santorini and the
tympanomastoid suture
Via venous channels and fascial planes within the
temporal bone
Along the middle and posterior fossa surfaces
Reaching the petrous apex (Gradenigo’s syndrome)
May cross midline
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The otic capsule exhibits significant resistance.
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Spread to skull base and involvement of IX, X, XI
cranial nerves (Vernet’s syndrome)
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Intracranial invasion:
 Meningitis
 Intracranial abscess
 Septic thrombosis of the sigmoid sinus or internal jugular
vein
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Extracranial extension:
 Prevertebral / parapharyngeal abscess
 Spread to sympathetic plexus around carotid sheath
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Bacteria
 Pseudomonas aeruginosa
 Staphylococcus epidermidis
 Staphylococcus aureus
 Klebsiella spp.
 Proteous spp.
 Non-tuberculous mycobacteria (NTM)
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Fungus
 Aspergillus fumigatus
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Pseudomonas aeruginosa
 Gram-negative, obligate aerobic bacillus
 Not normal flora of the ear canal
 Colonization after significant water exposure or
minor trauma
 A mucoid layer carrying lytic enzymes 
necrotizing vasculitis
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Non-tuberculous mycobacteria (NTM)
 Mycobacterial species other than the M. tuverculosis
complex or M. lerae
 Rapidly growing mycobacteria
 Slowly growing mycobacteria
 Diagnosis:
▪ Repeated isolation of the same NTM species
▪ Typical granulomas or presence of mycobacteria on
histopathology
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Fungus
 Less commonly associated with diabetic patients
 Immunocompromised patients (e.g. HIV,
hematologic malignancies)
 History of chronic otitis media
 Most common: Aspergillus fumigatus
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Diabetic patients
 Defects in: chemotaxis, phagocytosis, oxidative
burst and killing function of PMNs, and cellular
immunity
 Neutral pH of the cerumen
 Diabetic microangiopathy  Ischemia
 P. aeruginosa infections
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Patients with HIV infections
 Decreased numbers of CD4 T cells
 Impaired chemotaxis and neutrophil
degranulation
 Blunted humoral immue response
 P. aeruginosa infections (CD4 <100/mm3)
 Invasive Aspergillus infections (CD4 <50/mm3)
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After water exposure or trauma
“Deep” otalgia
 Severe, unremitting, and throbbing pain
 May accompanying headache and TMJ pain
 Worse at night
 Refractory to analgesics
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Fever is uncommon.
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Diabetic or immunocompromised patients
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A tender and swollen external auditory canal
A granulomatous polyp in the floor of the
external auditory canal at the bonycartilaginous junction
Cranial nerve palsy (Most common: CN7)
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Petrous apicitis
1907, Gradenigo:
 Triad: Constant otorrhea, headache, diplopia
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Diagnostic Criteria
 Suppurative otitis media
 Pain in the distribution of the trigeminal nerve
 Abducens nerve palsy
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Jugular foramen syndrome
Paralysis of the glossopharyngeal, vagus, and
accessory cranial nerves
Causes:
 Skull bass osteomyelitis
 Trauma
 VZV infection
 Cholesteatoma
 Giant cell arteritis
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Culture
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Tissue biopsy
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Laboratory studies
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Image studies
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Leukocytosis
Erythrocyte sedimentation rate (ESR)
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Evaluation for diabetes
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HRCT of temporal bone
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MRI
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Technetium-99 SPECT
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Gallium-67 Scan
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Skull base bone destruction
 More than 30% of affected bone demineralization
to appear eroded on CT
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Abscess formation
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Not an appropriate exam to evaluate response
 Remineralizaiton of afflicted bone may never occur
despite resolution of the infection.
Erosion of the tympanic plate along the
posterior margin of the mandibular fossa
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Identifying soft tissue changes
High signal intensities on T2-WIs
Dural enhancement
Involvement of the medullary space of bone
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Change in MRI do not resolve with disease.
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Trigeminal ganglion in Meckel cave
CN6 Abducens Nerve
Jugular Foramen
Hypoglossal canal
Petrous apex (small arrow)
Constriction of the carotid artery (large arrow)
Invovement of infratemporal fossa
Invovement of paraspinal space
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Areas of increased osteoblastic activity
Infection, trauma, neoplasm, and
postoperative conditions
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Three phase bone scan
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 Immediately after injection (blood flow phase)
 15 minutes after injection (blood pool phase)
 4 hours after injection (osseous phase)
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Osteomyelitis: intense uptake in all 3 phases
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Earlier diagnosis of osteomyelitis
 Bone demineralization need not be present.
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The 99Tc bone scan remains positive for
several months after clinical resolution.
 Bone repair continues for a prolonged period after
injury.
Grade I: Mild uptake
Grade II: Focal mastoid/temporal bone uptake not reaching midline
Grade III: Petrous temporal bone uptake reaching midline
Grade IV: Uptake crossing midline to involve the contralateral side
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Areas of active inflammation (infection) by
binding to acute phase reactants
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It should be repeated every 4 weeks to
monitor antibiotic response until it is normal.
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It returns to normal sooner once the infection
is resolved.
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Antipseudomonal antibiotics
 Ceftazidime
 Ciprofloxacin
 Ticarcillin or piperacillin
 3rd or 4th cephalosporin (e.g. cefepime)
 Carbapenem (e.g. imipenem)
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Ceftazidime
 A third generation cephalosporin
 Bactericidal activity against P. aeruginosa
 Monotherapy
 Combined with an aminoglycoside to:
▪ Broaden the spectrum
▪ Reduce resistance
▪ Potentially improve treatment result
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Ciprofloxacin
 Strong bone penetration
 Effectiveness against Pseudomonas
 Rapid accumulation in tissue with oral administration
 A mild side effect profile
 Rising resistance?
 Magnesium salts reduces GI absorption.
 Concurrent administration with theophylline can lead
to toxicity.
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Treatment time
 At least 4 to 8 weeks
 A change to oral antibiotic after an initial 2 week
course of IV combined therapy in patients with
early disease
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The previous treatment of these patients
with topical or oral antibiotics often leads to
negative cultures of the external auditory
canal.
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Bacterial identification and sensitivities ?
Djalilian HR et al. 2006
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A retrospective study
8 consecutive patients over a 2-year period
Median age: 54 years (42-84 yr)
Comorbidity: all pts with DM
Treatment
 Topical polymyxin, neomycin, and hydrocortisone
 Oral ciprofloxacin (750mg two times per day)
 Intravenous ceftazidime (2g every 12 hours)
▪ Peripheral intravenous central catheter (PICC)
Hospitalization
Treatments
for 4 days
at home
• Lab exams
• 99Tc bone scan
• 67Ga scan
• Start Tx
• Topical otic
• Oral ciprofloxacin
• IV ceftazidime
Week 6
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67Ga scan: all
negative
• Remove PICC
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NTM infection (combination therapy)
 Antibiotics
▪ Duration of medical treatment: average 7 months
▪ Until a disease free period of 4-6 months
 Surgical debulking or clearance of disease
Petrini B 2008
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Biopsy
Debridement of granulation tissue
Decompression of cranial nerves
The first-line treatment of osteomyelitis in
areas other than the cranial base includes
aggressive debridement of devitalized tissue.
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Mastoidectomy
Petrosectomy
 Infracochlear approach
 Transmastoid infralabyrinthine approach
 Middle fossa approach
 Translabyrinthine approach
 Transotic appoach
Infracochlear approach
Transmastoid
infralabyrinthine approach
Middle fossa approach
Translabyrinthine approach
Transotic approach
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Removal of the bone circumferentially
around the sound conduction/transduction
pathway
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Intraoperative facial and trigeminal nerve
monitoring
Visosky AMB et al. 2006
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A curved incision
begins at 0.2 cm
posterior and inferior
to the mastoid tips,
and ends at the
zygomatic zoot in the
preauricular crease.
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The skin and
temporoparietal fascia
is reflected anteriorly
and inferiorly.
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The temproralis
muscle is reflected
inferiorly, and the
anterior edge is left
attached to the
periosteum.
A mastoidectomy is
performed along with
an extended facial
recess approach.
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The facial nerve is
skeletonized.
The bone overlying the
posterior and middle
fossa dura and the
sigmoid sinus is removed.
The semicircular canals
are skeletonized.
The integrity of the
external auditory canal is
preserved.
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A craniotome is used to
turn a bone flap from
the sinodural angle to
the zoot of zygoma.
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The petrous apex is
exposed by elevating
the middle fossa dura.
The internal auditory
canal and the
semicircular canals are
skeletonized.
The anterior 1/3 of the
temporalis muscle is
left in place.
 The middle 1/3 is
inserted into the
petrous apex defect.
 The posterior 1/3 is
used to fill the mastoid
and the jugular fossa.
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Pts
Age Sex
Diagnosis
Operation
 Modified circumferential
petrosectomy and complete
mastoidectomy
1
8
M
Gradenigo syndrome
Tolosa-Hunt Syndrome
2
14
M
Gradenigo syndrome
Modified circumferential
petrosectomy
Modified circumferential
petrosectomy
Mastoidectomy (zygomatic and
supralabyrinthine air cells)
3
66
F
Acute mastoiditis with
petrous apicitis
Facial palsy
4
84
M
Cranial base osteomyelitis
Facial palsy
Modified circumferential
petrosectomy
5
56
F
Cranial base osteomyelitis
Circumferential petrosectomy
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Culture-directed antibiotic therapy as the first-line
treatment.
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For recalcitrant disease, the circumferential
petrosectomy provides the capability to debride the
necrotic bone and the inflammatory tissue with a
low risk of morbidity.
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This procedure can be tailored to the extent of the
patient’s disease.
Visosky AMB et al. 2006
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Success in the treatment of osteomyelitis
elsewhere in the body
Oxidative killing by leukocytes of aerobic
bacteria (P. aeruginosa)
In otogenic skull base osteomyelitis, it did not
influence disease-specific survival.
Grade I: Mild uptake
Grade II: Focal mastoid/temporal bone uptake not reaching midline
Grade III: Petrous temporal bone uptake reaching midline
Grade IV: Uptake crossing midline to involve the contralateral side
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Poor prognostic factors:
 Fungal / mixed infection
 Immunocompromised
 Cranial nerve palsy
 Intracranial extension
Otogenic Skull Base Osteomyelitis
Etiology
• Malignant otitis externa / Otitis media
Pathogen
• Pseudomonas aeruginosa
Diagnosis
• Culture
• MRI / CT / 99Tc scan / 67Ga scan
Medical treatment
• Antibiotics (ceftazidime, ciprofloxacin)
Surgical treatment
• Biopsy / Debridement / Decompression of the
cranial nerves
Prognosis
• A prolonged treatment course
• Significant morbidity and mortality
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Lee S et al., Otogenic cranial base osteomyelitis: a proposed prognosisbased system for disease classification. Otol Neurotol 2008; 29: 666-272
Sreepada GS et al., Skull base osteomyelitis secondary to malignant
otitis externa. Curr Opin Otolaryngol Head Neck Surg 2003; 11: 316-323
Djalilian HR et al., Treatment of culture-negative skull base osteomyelitis.
Otol Neurotol 2006; 27: 250-255
Merchant S et al., Osteomyelitis of the temporal bone and skull base in
diabetes resulting from otitis media. Skull Base Surg 1992; 2(4): 207-212
Petrini B, Non-tuberculous mycobacterial infections. Scad J Infect Dis
2006; 38: 246-255
Horwich P, Approach to imaging modalities in the setting of suspected
osteomyelitis. Uptodate 2008
Coker NJ et al, Atlas of otologic surgery. 1st Ed. Saunders
Visosky AMB et al., Circumferential petrosectomy for petrous apicitis and
cranial base osteomyelitis. Otol Neurotol 2006; 27: 1003-1013