Figure 60-3 The narrower part of the adult larynx (cylindric shape (A) occurs at the glottic opening, whereas the narrowest part of the infant larynx (funnel shaped) (B) occurs at the level of the cricoid cartilage. The normal adult configuration of the larynx is not achieved until the teenage years. This anatomic difference is one of the reasons why uncuffed endotracheal tubes are preferred for children younger than 6 years. A, anterior; Cricoid, cricoid cartilage; P, posterior. (Redrawn from Coté CJ, Todres ID: The pediatric airway. In Coté CJ, Ryan JF, Todres ID, et al [eds]: A Practice of Anesthesia for Infants and Children. Philadelphia, WB Saunders, 1992, p 55.)