Collagen implants in the human larynx. Pathological examinations of two cases.

We have studied two postmortem human laryngeal specimens after the injection of collagen. The first larynx was removed 14 days after injection, while the second was examined 5 months after injection. The specimens are described macroscopically and microscopically. Excellent tolerance to the collagen was noted, with virtually no inflammatory reaction seen. The collagen injected seems to have been colonized progressively by the host cells and by neovessels. These findings coincide closely with those observed in animal models. In comparison to the inflammatory granulomas found after injections with Teflon, the absence of inflammatory reactions following the use of collagen does at least contribute to justifying its continued application clinically.