Objective: This study was conducted to compare the velopharyngeal function among the beagle dogs which the levator veli palatini (LVP) muscles construction has been experimentally changed.
Methods: Four groups of LVP muscle reconstruction were made (normal LVP, cut LVP, end-to-end sutured LVP, and overlapped-sutured LVP at the midline). Levator veli palatini contraction was induced by electrical stimulation or a hypercapnia condition to analyze the strength of the velopharyngeal closure using balloon with a blood pressure meter, and the electromyogram in those operated beagle dogs.
Results: Under a hypercapnia condition, the velopharyngeal function did not differ significantly among the 4 groups in the terms of velopharyngeal pressure. The strongest closure was shown at the overlapped sutured LVP group by electrical stimulation.
Conclusion: The reconstruction of overlapped sutured LVP showed the most effective closure. This study suggested that the palatoplasty should be conducted along the overlapped LVP (like Furlow method).
Keywords: muscle function; palatoplasty; velopharyngeal function.