Different surgical techniques have been described in the literature to increase vocal pitch. The purpose of this study is to systematically review these surgeries and perform a meta-analysis to determine which technique increases pitch the most.Data Sources
CINAHL, Cochrane, Embase, Medline, PubMed, and Science Direct.Review Methods
A systematic review and meta-analysis of the literature was performed using the CINAHL, Cochrane, Embase, Medline, PubMed, and Science Direct databases. Studies were eligible for inclusion if they evaluated pitch-elevating phonosurgical techniques in live humans and performed pre- and postoperative acoustic analysis. Data were gathered regarding surgical technique, pre- and postoperative fundamental frequencies, perioperative care measures, and complications.Results
Twenty-nine studies were identified. After applying inclusion and exclusion criteria, a total of 13 studies were included in the meta-analysis. Mechanisms of pitch elevation included increasing vocal cord tension (cricothyroid approximation), shortening the vocal cord length (cold knife glottoplasty, laser-shortening glottoplasty), and decreasing mass (laser reduction glottoplasty). The most common interventions were shortening techniques and cricothyroid approximation (6 studies each). The largest increase in fundamental frequency was seen with techniques that shortened the vocal cords. Preoperative speech therapy, postoperative voice rest, and reporting of patient satisfaction were inconsistent. Many of the studies were limited by low power and short length of follow-up.Conclusions
Multiple techniques for elevation of vocal pitch exist, but vocal cord shortening procedures appear to result in the largest increase in fundamental frequency.