Evaluation of atelocollagen implant therapy for a rabbit model of acquired tracheomalacia following tracheostomy.

PURPOSE: This study evaluated whether local atelocollagen gel administration prevented airway collapse in a rabbit model of acquired tracheomalacia after tracheostomy. METHODS: Japanese white rabbits (≥ 20 weeks) underwent anterior resection of the second-fourth tracheal rings with mucosal preservation. Group A received 1 mL of 3% atelocollagen around the trachea, whereas Group B was untreated. Bronchoscopy was performed preoperatively (Term 1), immediately postoperatively (Term 2), and 3-4 months postoperatively (Term 3). The tracheal lumen area was measured using negative-pressure suction. RESULTS: Six of seven rabbits in Group A and five of six rabbits in Group B survived. At 30 cmHg, lumen area (%) in Group A was 90.1 ± 19.9 (Term 1), 48.0 ± 40.4 (Term 2), and 69.0 ± 50.3 (Term 3), versus 99.4 ± 7.8, 53.4 ± 20.0, and 15.0 ± 18.8 in Group B. No differences were observed at Terms 1 or 2. At Term 3, lumen area decreased with increasing suction in Group B but was relatively preserved in Group A. Lumen area ≥ 50% at 30 cmHg was observed in 4/6 (66.7%) in Group A and 0/5 (0%) in Group B. CONCLUSION: Local atelocollagen administration may attenuate airway collapse in tracheomalacia at 3-4 months.