Purpose: To evaluate the effect of the different surgical techniques used in the treatment of obstructive sleep apnea (OSA) on the postoperative voice and nasalance, and to conduct a meta-analysis through the assessment of postoperative changes.
Methods: Systematic literature review and meta-analysis of published data using the data sources, MEDLINE, Google Scholar, Cochrane, and SAGE. All studies published in English specifying any upper airway surgery for treatment of snoring and/or OSA were included, provided they indicated the pre- and postoperative mean ± standard deviation (SD) values for voice parameters and nasality. The primary outcomes were the changes in preoperative-postoperative mean values of fundamental frequency (mF0), jitter, shimmer, and nasalance scores.
Results: After removal of duplications, 214 studies were potentially relevant, and 25 studies ultimately met the criteria for inclusion in the present review. Of the 25 studies evaluated in this review, 12 studies with 379 patients were available for the meta-analysis calculations. In general, a fixed-effects model was used to analyze the data in the subgroups. The meta-analysis results showed no significant differences in either subgroup analysis between the preoperative and postoperative assessments of mF0, jitter, shimmer, oral nasalance, nasal nasalance, and oronasal nasalance (All had values of p > 0.05).
Conclusion: The results of this meta-analysis indicated no significant effect of surgical treatments for snoring or OSA on glottic functioning and nasalance parameters, regardless of surgery type. Further prospective studies are needed to assess more parameters for detailed acoustic analyses.
Keywords: Meta-analysis; Nasalance; Obstructive sleep apnea; Snoring; Surgery; Voice.