Objective: To investigate differences in middle ear ventilation mechanisms between pars flaccida and pars tensa cholesteatoma.
Study design: Retrospective case review.
Setting: A referral hospital otolaryngology department.
Patients: Sixty-six ears with pars flaccida cholesteatoma (mean age, 45.7 yr) and 19 ears with pars tensa cholesteatoma (mean age, 58.8 yr) were included. Patients with totally adhesive tympanic membranes or mixed-type cholesteatoma were excluded.
Interventions: Patients underwent canal wall down tympanoplasty with canal reconstruction. The canal wall was reconstructed with tragal or conchal cartilage and cortical bone grafts.
Main outcome measures: Habitual sniffing, preoperative sonotubometry results, mastoid pneumatization (maturation), and postoperative aeration around the stapes were investigated. Preoperative mastoid pneumatization and postoperative aeration around the stapes were measured on computed tomography scans.
Results: Ten (15.4%) of 65 patients with pars flaccida cholesteatoma and 3 (15.7%) of 19 patients with pars tensa cholesteatoma were habitual sniffers (p = 0.5). Preoperative sonotubometry indicated that a patulous pattern was more common in ears with pars flaccida than pars tensa cholesteatoma (42.8% versus 7.1%, p < 0.05), and a stenotic pattern was more common in ears with pars tensa than pars flaccida cholesteatoma (85.8% versus 42.8%, p < 0.01). Preoperative mastoid pneumatization and postoperative aeration around the stapes were significantly better in ears with pars flaccida than pars tensa cholesteatoma (p < 0.01 and p < 0.05, respectively).
Conclusion: Significantly different tubal function and mastoid pneumatization patterns suggest differences in ventilation disorders and cause between ears with pars flaccida and pars tensa cholesteatoma.