Velopharyngeal function after two different types of pharyngoplasty.

OBJECTIVE: To evaluate velopharyngeal function after two different types of pharyngoplasty: pharyngeal flap (PF) and sphincter pharyngoplasty (SP).
DESIGN: Two groups of patients operated on with pharyngeal flaps or sphincter pharyngoplasty were studied prospectively.
SETTING: The study was carried out at the cleft palate clinic of the Hospital Gea Gonzalez in Mexico City. PATIENTS: Fifty-eight cleft palate patients were studied. All patients had undergone palatal repair and showed residual velopharyngeal insufficiency. Twenty-five patients were operated on using a pharyngeal flap. Twenty-three patients were operated on using a sphincter pharyngoplasty. MAIN OUTCOME MEASURES: Pharyngeal muscle function was evaluated using selective electromyography (EMG) and simultaneous videonasopharyngoscopy (VNP). The superior constrictor muscle was approached directly. The levator veli palatini was included in the central pharyngeal flap. The palatopharyngeus were included in the lateral and superiorly-based surgical flaps inserted on the posterior pharyngeal wall. All patients showed a complete velopharyngeal closure after surgery.
RESULTS: None of the patients showed muscle activity on the central pharyngeal flaps. None of the patients showed muscle activity on the lateral flaps of the sphincter pharyngoplasties. All the patients showed strong muscle activity of the superior constrictor.
CONCLUSIONS: It is concluded that lateral pharyngeal flaps in cases of sphincter pharyngoplasty and the central pharyngeal flap in cases of pharyngeal flap, show absence of intrinsic activity during speech. The participation of these structures when velopharyngeal closure occurs during speech is rather passive. These flaps, central or lateral, increase tissue volume on specific areas; their movements are produced by the underlying superior constrictor.