A histologic study of the growth of the subglottis after endolaryngeal trauma.

In young rabbits the histologic features of the growth of the subglottis were studied after an endolaryngeal trauma. This lesion of the larynx leading to a subglottic stenosis, caused specific pathologic changes of the cricoid cartilage and the subepithelial tissues. Activation of chondrocytes resulted in proliferation and regeneration of destructed cartilage. The normal subepithelial structures were replaced by granulation tissue differentiating into a thick fibrous scar and into cartilage. This ectopic cartilage together with the repaired cricoid formed a composite thickened 'ring'-like cartilaginous structure in the adult stage.