Abstract
Recently, atelocollagen has been brought forward as an injectable material to the vocal folds instead of silicone. But in the clinical use, the results sometimes are not satisfactory because collagen volume decreases in the vocal folds after injection. A fundamental study of injected collagen in the tissues was recommended.
3.0 and 3.5% collagen was injected in gluteus muscle of guinea pigs, and in the vocal folds of canines respectively, and observed under light microscope. The collagen injected in muscles is spread between muscle bundles but collagen injected in the lamina propria of the mucous membrane remained there making a mass. As a conclusion, a decrease of collagen volume after injection, is due to resorption of saline solution of collagen gel, spreading collagen between muscle bundles and a back-flowing of collagen from a hole made by an injection needle.
