Morphology of the human larynx during the first five years of life studiedon whole organ serial sections

The morphologic development of the human larynx during the first years of l ife is poorly understood to date. This study used plastinated whole organ s erial sections to determine the growth and structure of the infant larynx. The larynges of 43 children 1 to 60 months old were plastinated. Whole orga n serial sections were obtained by cutting the resulting specimen with a di amond band saw. The slices were then submitted to computer-assisted morphom etric investigation. We found that the subglottic airway rapidly increases in size during the first 2 years of life. Further growth follows a linear m ode. The relative proportion of the mucosal lining decreases likewise. In c ontrast to that in adults. and comparable to that in most mammals, the cart ilaginous glottis accounts for 60 % to 75% of the vocal folds' length at <2 years. No sexual dimorphism of the larynx exists during childhood. This st udy supplies detailed morphometric data on the growth and structure of the human larynx during the first years of life. It is the first to use plastin ated whole organ serial sections for morphology of the pediatric larynx. Th erefore, this study provides quantitative anatomic data of clinical interes t that have not been available to date.