Expansion of the infant subglottis by external cricoid distraction: an animal model

A technique is described to expand the subglottis by anterior cricoid split (ACS) combined with external cricoid distraction (ECD) using a posterior belly of digastric muscle sling. This technique was used on 5-week-old rats that were killed 6 weeks after surgery, and the larynges were examined histologically and compared with those of rats who underwent ACS alone. Information was available from ten animals in the ECD group and five in the ACS alone group. Separation of the cut ends of the cricoid was found to be maintained in all animals after ECD, the gap having been filled by fibrous tissue lined by respiratory epithelium. A lesser degree of cricoid separation was seen in the animals that underwent ACS alone.