ARYEPIGLOTTIC FOLD - NORMAL TOPOGRAPHY AND CLINICAL IMPLICATIONS

The aryepiglottic folds extend between the arytenoid cartilage and the lateral margin of the epiglottis on each side and constitute the late ral borders of the laryngeal inlet. They are involved in physiologic c losure mechanisms of the larynx and in pathologic conditions such as i nspiratory strider. Information on the normal topography of the aryepi glottic folds is poor and controversial. Therefore, this region was re investigated in serial whole-organ sections of 25 plastinated normal a dult human larynges. Dorsally, the right and the left aryepiglottic fo lds are separated by the interarytenoid notch and comprise the cornicu late and cuneiform cartilages, as well as numerous groups Of mucous gl ands. Ventrally, the aryepiglottic folds are adjacent to the peri-epig lottic adipose tissue. Both regions are clearly separated by several l ayers of transversely oriented collagenous fiber layers. The muscular constituent of the aryepiglottic folds is only poorly developed, and n o muscle fibers insert at the epiglottis. A coherent quadrangular memb rane representing a ligamentous ''skeleton'' of the aryepiglottic fold s is absent. A conspicuous collagenous fiber layer is found only to st rengthen the free dorsal margin of the fold. Both muscular and ligamen tous components may render the aryepiglottic folds sufficiently tense as to resist inspiratory inward suction in normal cases. However, plia bility must be preserved to guarantee adequate folding in approximatio n of the aryepiglottic folds during deglutition. Thereby, the posterio r part of the laryngeal inlet is closed, whereas the anterior part is probably closed by independent inward bulging of the peri-epiglottic a dipose tissue. (C) 1998 Wiley-Liss, Inc.