Contractility of sphincter pharyngoplasty: Relevance to speech outcomes

Sphincter pharyngoplasty has demonstrated time-tested results as a surgical treatment for velopharyngeal incompetence (VPI). However, controversy surrounding the contractility of the transposed muscles persists. Completely unaddressed in the literature is whether the dynamism of the sphincter affects speech outcomes.

To determine whether active sphincter contraction following sphincter pharyngoplasty influences velopharyngeal closure, nasal emission and hypernasality.

A prospective analysis of patients with VPI after cleft palate repair undergoing sphincter pharyngoplasty by a single surgeon was performed. Video nasendoscopy and videofluoroscopy were performed preoperatively and postoperatively at three and 12 months. Eighteen consecutive patients with cleft palate with or without cleft lip and VPI were reviewed. The average age of the patients at initial evaluation was 7.3 years, with a range of three to 19 years. Dynamicity of sphincter pharyngoplasty, velar closing ratio (VCR), and lateral wall movement (LWM) were assessed by nasendoscopy and videofluoroscopy. Nasal emission and hypernasality were assessed by perceptual speech examination.

FOR LONGITUDINAL COMPARISON, THREE GROUPS WERE CREATED: dynamic at three and 12 months (n=12); adynamic at three months and dynamic at 12 months (n=4); and adynamic at three and 12 months (n=2). Perceived hypernasality scores significantly improved at three months (P=0.0001) and showed continued improvement at 12 months (P=0.03), despite no change in VCR and LWM from three to 12 months. There were no significant differences among the three groups at any time point.

Sphincter pharyngoplasty effectively treats VPI in appropriately selected patients. Although the VCR and LWM remained stable between three months and one year, four of six adynamic sphincters became dynamic. Considering all patients, hypernasality showed continued improvement from three months to one year.

There were no differences between dynamic and adynamic sphincters in terms of speech outcomes or the mechanical properties of velopharyngeal closure.