Vocal fold injection of collagen for unilateral vocal fold paralysis caused by chest diseases

Background. Patients having malignant chest diseases sometimes suffer from vocal fold paralysis. Treatment for vocal fold paralysis is important for such patients, because vocal fold paralysis causes lack of the versatility of the human voice which is essential for our communication. Methods. Seventeen patients suffering from unilateral vocal fold paralysis were treated with vocal fold injections of collagen. Three patients received twice, and 20 treatments were conducted. A flexible bronchofiberscope was used under local anesthesia in order to observe the whole procedure of vocal fold injection. Using an injector and a long needle, collagen was injected with transcutaneous technique mainly through the cricothyroid membrane. The amount of collagen was determined with bronchoscopic findings. Results. During and after treatment, no complication was observed. Of 20 treatments, a marked improvement was observed in 8, and moderate improvement was observed in 9 treatments. Conclusions. Vocal fold injection of collagen is a very useful and safe treatment for unilateral vocal fold paralysis caused by chest diseases.