The vocal folds are a small, yet complex structure of muscles that require a lot of hydration to work properly. The thyroarytenoid muscle (aka vocalis muscle) is the innermost part, which is covered in several layers of a Jello-like substance of mucosa called the lamina propria. It is soft, elastic, and covered with epithelium, which is a thin layer akin to loose skin. Just as our skin can get red and irritated if it’s too dry, this can happen to the vocal folds too, leading to the same issues, plus swelling.
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