Three-dimensional reconstruction of vocal fold geometrical deformation induced by formalin fixation

Abstract

In our previous study [Kimura et al., J. Acoust. Soc. Am. 109, 2413 (2001)], we showed that significant tissue deformation and distortion of vocal fold geometry is induced by the commonly used histological procedure of formalin fixation. Significant shrinkages of the vocal fold body (thyroarytenoid muscle) and considerable distortion of the vocal fold cover (particularly the free edge) were observed. In mid-membranous coronal sections of canine tissues, there was an average of 20% shrinkage in vocal fold thickness and 40% shrinkage in vocal fold depth. This paper reports a three-dimensional (3-D) follow-up to these two-dimensional measurements. Vocal fold coronal sections every 2 mm along the anteroposterior direction were prepared from the same canine tissue samples, allowing for 3-D reconstruction of geometrical deformation. Results showed that the free edge of the vocal fold cover was significantly deformed, as emphasized by 3-D images.