Pharyngeal Flap Surgery and Nasal Airway Resistance.

Pharyngeal flap operations are commonly performed in the treatment of velopharyngeal insufficiency in patients with cleft palate or congenital velopharyngeal insufficiency (CVPI). It has been reported that nasal obstruction following this procedure usually disappears in 4 to 6 months.As previously reported, the difference between nasal resistance determined by the activeposterior method (Pp) and that determined by the active-anterior method (Pa) is thought to reflect the resistance of the nasopharynx or the pharyngeal flap.In the present study, we measured nasal airway resistance by both the active-posterior and the active-anterior methods before and after surgery periodically in 13 patients with cleft palate or CVPI, aged 5 to 24 years. The control group consisted of 57 patients with cleft palate without pharyngeal flap surgery, aged 4 to 36 years.The normal range of (Pp-Pa) was determined to be +0.2Pa/cm3/sec to -0.2Pa/cm3/sec because the value of (Pp-Pa) fell into this range in 55 out of 57 control subjects. The value of (Pp-Pa) returned to the normal range 6-7 months after flap surgery in 11 patients. However, it still remained abnormal 9 months following the procedure in 2 patients with stenosis of the lateral porus. Thus, if the flap operation is performed correctly, breathing through the nose is thought to normalize 6'-7 months after the pharyngeal flap operation.