A Portable High-Speed Camera System for Vocal Fold Examinations

SummaryAimIn this article, we present a new portable low-cost system for high-speed examinations of the vocal folds. Analysis of glottal vibratory parameters from the high-speed recordings is compared with videostroboscopic recordings.Methods and ResultsThe high-speed system is built around a Fastec 1 monochrome camera, which is used with newly developed software, High-Speed Studio (HSS). The HSS has options for video/image recording, contains a database, and has a set of analysis options. The Fastec/HSS system has been used clinically since 2011 in more than 2000 patient examinations and recordings. The Fastec 1 camera has sufficient time resolution (≥4000 frames/s) and light sensitivity (ISO 3200) to produce images for detailed analyses of parameters pertinent to vocal fold function. The camera can be used with both rigid and flexible endoscopes. The HSS software includes options for analyses of glottal vibrations, such as kymogram, phase asymmetry, glottal area variation, open and closed phase, and angle of vocal fold abduction. It can also be used for separate analysis of the left and vocal fold movements, including maximum speed during opening and closing, a parameter possibly related to vocal fold elasticity. A blinded analysis of 32 patients with various voice disorders examined with both the Fastec/HSS system and videostroboscopy showed that the high-speed recordings were significantly better for the analysis of glottal parameters (eg, mucosal wave and vibration asymmetry).ConclusionsThe monochrome high-speed system can be used in daily clinical work within normal clinical time limits for patient examinations. A detailed analysis can be made of voice disorders and laryngeal pathology at a relatively low cost.