Electronic Speckle Pattern Interferometry of the Vibrating Larynx

Abstract

Laser holography is a technique that creates a three-dimensional image of a static object. This technique can be applied to the analysis of vibrating structures. Electronic speckle pattern interferometry uses a laser for illumination of the vibrating object and solid state detectors and digital hardware technology for capturing and processing the image in real time. This was performed on a human cadaver larynx and is the first time an interferogram of vibrating vocal cords has ever been obtained. Dark and bright interference fringes are seen that represent the vibratory motion of the vocal folds. These are presented in still photos as well as real-time on videotape. This method can provide advantages over current techniques of laryngeal study: it is sensitive to motion in the vertical dimension, and the digital data can be quantitatively analyzed. Application of this technique to study the larynx should eventually be a valuable clinical tool and provide quantitative research data.

Dynamic imaging of vocal fold oscillation with four‐dimensional optical coherence tomography

“…The enlargement shows that the system was able to resolve small modes of oscillation of the surface whose amplitude is only about 100 μm. Details of mucosal wave shape on such a small scale have not been previously possible to observe with other technologies, save possibly the interferometric holographic system of Gardner 13…”

“…In previous studies the hemilarynx model was used extensively for characterizing vocal fold dynamics,11, 15–17 and optical triangulation was used to reconstruct the motion of the vocal fold surface. Other methods were used for tracking the vocal fold surface, such as x‐ray tracking of pellets21 and interferometry 13. An obvious advantage of 4D OCT is the high‐resolution dynamic imaging of the surface and the upper 1 to 2 mm of the lamina propria, which cannot be accomplished with other methods.…”

Medial surface dynamics of anin vivocanine vocal fold during phonation

“…[9][10][11] Because of the difficulty in imaging the medial surface of the vocal folds, only a few quantitative studies have attempted such imaging. [12][13][14][15][16] However, of these investigations, Berry et al 16 was the only study to image and quantify the medial surface of the vocal folds with sufficient spatial and temporal resolution to enable extraction of the underlying modes of vibration, sometimes referred to as Empirical Eigenfunctions. 17 Such modes have been shown to be helpful for investigating mechanisms of both normal and abnormal voice production.…”

Advances in the Development of the Interferometric Otoscope

“…Subsequent to the original work by Khanna and Tonndorf, 1 advances in the use of laser interferometry further elucidate the subtleties of tympanic membrane characteristics 3‐6 . Furthermore, in our laboratory, we have integrated advances in electrooptic technology (fiber optics, miniature diode lasers, solid‐state detection arrays) and digital processing to study vibratory characteristics of cadaveric human vocal cords 7‐9 . In this experiment, we demonstrate quantitative static and dynamic vibration/displacement characteristics of a human tympanic membrane based on measurements using electronic speckle pattern interferometry (ESPI).…”