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Updated: Jul 5, 2025

Minimally Invasive Murine Laryngoscopy for Close-Up Imaging of Laryngeal Motion During Breathing and Swallowing
Published on: December 1, 2023
Body positioning-related laryngeal narrowing pattern and expiratory mechanical constraints in advanced chronic
Yuka Nagata1, Keisuke Miki1, Ryo Kijima1
1Department of Respiratory Medicine, NHO Osaka Toneyama Medical Center, 5-1-1 Toneyama, Toyonaka, Osaka, 560-8552, Japan.
Abstract:
We previously reported that laryngeal widening led to improved exercise tolerance in COPD. However, it is not clear whether laryngeal narrowing occurs as a compensatory response to tracheal movement or is affected by posture. Here, we report the case of an advanced COPD patient whose more prolonged expiration in a head-forward leaning position compared with that in a neck-extended position occurred with an excessive duration of severe laryngeal narrowing without tracheal obstruction, which led to exercise intolerance with expiratory mechanical constraints. This case provided useful insights into the regulation of the upper airway with body positioning for improving exercise tolerance.
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