Universal Modular Glottiscope System: The Evolution of a Century of Design and Technique for Direct Laryngoscopy

Abstract

Since Kirstein introduced formal direct examination (autoscopy) of the glottis in 1895, a great number of laryngoscopes have been produced to view the vocal folds; however, none have had universal appeal. The primary goals for the designs have been to optimize exposure and to facilitate instrumentation of the glottis. An analysis of more than 50 laryngoscopes was done to assess key design characteristics that would ideally be present in a laryngoscope for optimally viewing the musculomembranous vocal folds. The Pro/Engineer and Pro/Mechanica computer programs were used to model the universal modular glottiscope. This new laryngoscope comprises a plurality of specially designed examining tubes that are bivalved proximally to improve utilization of hand instrumentation, and form a single tube distally to achieve internal distention of the supraglottal tissues. The distal lumen has an arcuate isosceles-triangular conformation to optimally expose the glottis. The base of the tube is detachable for the difficult intubation or the placement of bronchoscopes. The examining tubes vary in size and dimension to accommodate the diversity of human anatomy. The tubes are easily attachable to and detachable from an ergodynamically designed universal handle that can be joined to fulcrum laryngoscope holders or suspension gallows. The universal modular glottiscope evolved from the selective integration of optimal 20th-century design modifications of Kirstein's original autoscope. This new laryngoscope is ideally suited for phonomicrosurgery as well as for difficult intubation.