Histological study of atelocollagen infused into the human vocal cords

There have been only three case reports of histological study on injection of atelocollagen into the human vocal cords, and none of these have indicated foreign body reaction. We histologically examined the larynx of a 70-year-old man, which had to be excised 44 days after infusion of atelocollagen into the vocal cords. The atelocollagen infused was found to have been replaced with the collagen of host cells, but no foreign body reaction was observed. As in conventional reports, the histoaffinity of atelocollagen was confirmed.