Exploration of glottic function before and after injection of collagen for rehabilitation of the vocal cord.

After more than one year's use of injectable collagen for vocal and glottic rehabilitation, the subjective and objective results have been presented for a series of 18 patients, 17 of whom had paralysis of one vocal cord, while one patient had a post-traumatic atrophy of the left cord. The assessment is based on rigid and flexible fibroscopy, stroboscopy, the objective phonatory assessment with measurement of the phonatory quotient and mean flow rate, EMG of the vocal cords and frequential analysis of the voice. Apart from the improvement in the phonatory quotients and outputs after injection, the noteworthy results have been the persistence of flexibility and undulation in the cord injected, visible by stroboscopy, and also the reappearance of the fundamental and 2 or 3 first harmonics on frequential analysis of the voice. The mean follow-up was 6.5 months, with a maximum of 14 months and minimum of 1 month. At the medium term, injectable collagen would appear to be a worthwhile alternative to Teflon because of its simplicity of use, its very great tolerance and the quality of the functional results obtained.