A Case of Nocturnal Stridor with Combined Obstructive Sleep Apnea Caused by Bilateral Vocal Cord Palsy

Bilateral vocal cord palsy is one of the causes that trigger nocturnal stridor and obstructive sleep apnea (OSA), and three cases of OSA due to bilateral vocal cord paralysis have been described in the medical literature. In 1987, Ruff et al.1 reported a case of bilateral vocal cord palsy and sleep apnea in a patient with type I Chiari malformation. In 1996, McBrien et al.2 reported a case of bilateral vocal cord palsy in a patients with Shy-Drager syndrome (multiple system atrophy with autonomic phenomena) who sought treatment for nocturnal stridor and sleep apnea. In 2003, Luaazy and Hasse described a patient with breathing difficulty, snoring and severe OSA which were caused by bilateral vocal cord palsy of unknown origin.3 In addition to vocal cord palsy, there were several reports that congenital and acquired factors have resulted in a collapse of glottis structures that, in turn, has resulted in laryngeal stridor and OSA.4,5 In this aspect, the role of laryngeal structure, including vocal cord, to develop laryngeal stridor and OSA is important. However, the role was overlooked by many clinicians. And laryngeal exam was not routinely performed to investigate the cause of OSA. In this article, we describe a case of nocturnal stridor with combined OSA which was caused by undiagnosed bilateral vocal cord palsy and review the importance of laryngeal exam to find the problems of glottis structures.