The 'acquired' pathogenesis theory of cholesteatoma most widely accepted today involves:
- A Metaplasia of the middle ear respiratory epithelium into keratinising squamous epithelium
- B Invagination/retraction of the pars flaccida (Shrapnell's membrane) secondary to Eustachian tube dysfunction, forming a retraction pocket ✓
- C Implantation of squamous epithelium through a traumatic perforation
- D Failure of regression of the first branchial groove epithelium
Correct answer: B. Invagination/retraction of the pars flaccida (Shrapnell's membrane) secondary to Eustachian tube dysfunction, forming a retraction pocket
Explanation
The most widely accepted mechanism for acquired primary cholesteatoma is retraction-pocket theory: chronic negative middle ear pressure from Eustachian tube dysfunction causes inward retraction of the pars flaccida, forming a self-deepening pocket that accumulates desquamated keratin — this is a cholesteatoma. Secondary acquired cholesteatoma occurs by epithelial migration through a pre-existing perforation. Metaplasia and branchial remnant theories account for a minority of cases.
Reference: Dhingra Diseases of Ear, Nose and Throat, 7th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
Written and medically reviewed by the StethoPrep medical team.