D. Zanetti et al., Surgical repair of bone defects of the ear canal wall with flexible hydroxylapatite sheets: A pilot study, OTOL NEURO, 22(6), 2001, pp. 745-753
Objective: Evaluation of suitability of flexible composite sheets (hydroxyl
apatite and polymer) for outer ear canal (OEC) wall reconstruction in tympa
noplasty.
Study Design: Prospective, open label pilot study.
Setting: University and regional hospital.
Patients: Forty-two randomly selected patients with chronic otitis media (n
= 20) and cholesteatoma (n = 22) among 356 patients admitted between 1996
and 1997.
Interventions: Eradication of disease through a partial or total canal wall
down mastoidectomy; immediate reconstruction of canal wall with flexible c
omposite sheet (hydroxylapatite and polymer) and connective tissue graft.
Outcome Measures: Anatomic integrity of the OEC and neotympanum, extrusion
rate, complications.
Results: At minimum follow-up of 24 months: recurrent cholesteatoma (n = 0)
, residual cholesteatoma (n = 3/22) (13.6%) in the mesotympanum (none behin
d the hydroxylapatite sheet or in the attic or antrum). The neotympanum was
intact in 38 ears (90.4%), reperforated in 2, and severely retracted and l
ateralized in 1, respectively. Anatomic integrity of the OEC was obtained i
n 37 (88%) of 42 patients, stenosis or membranous synechiae were observed i
n 5 ears and treated in the office. Extrusion of the hydroxylapatite sheet
occurred in 7 patients (16.6%) because of purulent otorrhea and granulation
tissue formation. Surgical revision achieved complete epithelialization of
the rebuilt canal wall in 33 ears (78.6%).
Conclusions: A dry, disease-free ear and normal anatomy may be expected 2 y
ears postoperatively in more than three-fourths of the patients treated usi
ng the described surgical technique. Complete protection with a connective
tissue graft is essential to avoid extrusion of the implant. The failure ra
te is significantly higher if otorrhea is present at the time of the operat
ion.