Invention of the Flexible Fiberoptic Nasopharyngolaryngoscope: Perspectives From the East

OBJECTIVES: To trace the historical origins of the fiberoptic nasopharyngolaryngoscope (laryngoscope) and to shed light on the innovative scientists who developed this technology. DATA SOURCES: Primary sources included original research articles and abstracts reporting the initial development of the fiberoptic laryngoscope and similar technologies, original documents from the University of Tokyo's Research Institute of Logopedics and Phoniatrics (RILP) Annual Bulletin, and an interview with the lead inventor. REVIEW METHODS: Available information was reviewed regarding: how and why the fiberoptic laryngoscope was developed, what technologies preceded this development, who the inventors were, what historical context this technology was shaped in, and its long-term impact. RESULTS: The fiberoptic laryngoscope was invented in 1967 by Drs. Masayuki Sawashima, Hajime Hirose, and Osamu Fujimura at the University of Tokyo's RILP. This groundbreaking innovation arose during a wave of rapid technological advancement in Japan following World War II. Dr. Sawashima highlights that a key inspiration for the fiberoptic laryngoscope was the success of the fiberoptic bronchoscope, developed by Japanese physician-scientist Dr. Shigeto Ikeda in 1962. The inventors of the fiberoptic laryngoscope reported the first real-time images and videos of the glottis during unperturbed speech and breathing, revolutionizing understanding of laryngeal function and setting the stage for modern laryngology and speech language pathology. According to Dr. Sawashima, the team never patented their technology. CONCLUSION: The flexible laryngoscope was invented in 1967 by Sawashima, Hirose, and Fujimura at the University of Tokyo RILP, a foundational contribution to modern laryngology that has gone largely unrecognized in English-language literature. LEVEL OF EVIDENCE: NA.