Swallowing evaluation after surgery for obstructive sleep apnea syndrome: uvulopalatopharyngoplasty vs. expansion pharyngoplasty.

Purpose: To evaluate the effect of pharyngeal surgery on swallowing pattern in patients with obstructive sleep apnea syndrome (OSAS), and to compare two surgical techniques: uvulopalatopharyngoplasty (UPPP) and expansion pharyngoplasty (EP), through videofluoroscopy.
Methods: Longitudinal prospective cohort, in a tertiary referral center. 17 adult patients were enrolled this study, divided into two groups: patients who underwent UPPP (n = 10) or EP (n = 7). Swallowing videofluoroscopy (for both liquid and pasty consistences) was assessed at three different periods: before surgery, and at 14 and 28 days following surgery. Comparisons were performed between pre- and post-operative (PO) swallowing conditions in the same patient, and between surgical techniques.
Results: Asymptomatic OSAS patients already presented altered swallowing pattern before surgery. Both surgical procedures led to an increased hyoid movement time and an increased frequency of laryngeal penetration in early PO during liquid ingestion. For pasty consistency, both techniques reduced velum movement time and increased pharyngeal transit time and the rate of stasis in hypopharynx. All these parameters reached or tended to reach the pre-operative indices at day PO 28.
Conclusions: OSAS patients show sub-clinical changes in swallowing pattern before surgery. Both surgical techniques are related to transitory changes in swallowing biomechanics. Complete or partial reversal to pre-operative swallowing parameters occurs 1 month after both surgery techniques.