The problem mastoid cavity

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The problem mastoid cavity

• Iain R C Swan

Perth, 2008
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Why do mastoid cavities remain active?

• Most active cavities have obvious deficiencies
• Major reason is poor surgical technique
• Wormald Nilssen, 1998
• Level 2 evidence

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Management of problem cavities

• Identify problem
• Often multiple
• narrow meatus
• facial ridge
• perforation
• Two main groups
• small, epithelialised cavities
• large or non-epithelialised cavities

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Epithelialised cavities

• Usually endaural approach
• Meatoplasty
• Take down facial ridge
• Remove all overhangs
• Preserve cavity lining if possible

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Non-epithelialised cavities

• Conservative
• toilet
• topical medication
• pinch grafts
• If fails, obliteration

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Mastoid obliteration materials

• Soft tissue
• resorbs rapidly
• Small cavity
• Cartilage meatus
• tragus
• Large cavity
• bone pate
• hydroxyapatite granules expensive
• SeronoCem granules

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Mastoid obliteration bone pate

• Post-auricular approach
• vascularised flap

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• Inferiorly based fascio-periosteal flap
• Include temporalis fascia, not muscle

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Collect bone pate

• Do not open into cavity
• Collect clean bone pate
• Moffat-Robinson collector

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Bone pate

• Mix with aqueous betadine or antibiotic
• Dry with swab

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• Revise cavity
• sinodural angle
• facial recess
• Lower facial ridge - not too much
• Remove cortical bone inferiorly
• removes angle for flap
• Small meatoplasty

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• Ossicular reconstruction if appropriate
• Close TM
• fascia
• tip of fascio-periosteal flap

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Obliterate cavity

• Ensure cavity is reasonably dry
• Fill cavity with pate

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• Cover with fascio-periosteal flap

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Results of obliteration

• n
• Inactive
• Intermittently active
• Active

48 85 7 8
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Outcome of obliteration

• Complete
• Partial
• Failed

61 27 12
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Problems with obliteration

• Concealed cholesteatoma
• avoid in presence of cholesteatoma?
• meticulous technique
• Resorption of bone
• slow
• does it matter?