Pharyngeal Flap Surgery - Pharyngeal Flap Procedures

Pharyngeal Flap Procedures

Posterior pharyngeal flap surgery is the most commonly used operation to restore velopharyngeal competence (i.e., develop a functional seal between the nasal cavity and the oral cavity), and therefore correct hypernasality and nasal air escape (Ysunza et al., 2002). Posterior pharyngeal flaps can be based superiorly or inferiorly and the velum can be split transversely or along the midline (Lideman-Boshki et al., 2005). Centrally positioned, superior based flaps continue to be the most popular pharyngeal flap choice, yet inferior based flaps are easier for the surgeon to perform. Compared to superiorly based flaps, inferiorly based flaps are limited in regard to the size of velopharyngeal opening that can be covered (Peterson-Falzone et al., 2001).

Pharyngoplasties correcting hypernasal speech can be traced back as far as the 19th century when Passavant first explored palatopexy in a 23-year-old female (Hall et al., 1991). In 1876, Schoenborn also attempted to reduce the amount of air entering the nasal cavity by developing the first true inferior based pharyngeal flap surgery, where a flap of tissue was sutured into the velum and attached to the lower end of the posterior pharyngeal wall. Modifying his technique, Schoenborn published a superior based pharyngeal flap surgery in 1886, where the flap of tissue attached to the upper end of the posterior pharyngeal wall. In 1928, Rosenthal used an inferiorly based posterior pharyngeal flap in combination with a modified von Langenbeck palatoplasty in primary surgery for cleft palate repair. Taking a different approach, Padgett (1930) utilized a superiorly based flap for cleft palate patients whose primary surgical repair had been unsuccessful (Sloan, 2000). By the 1950s, posterior pharyngeal flap surgery became widely adopted in the correction of VPI (Peterson-Falzone et al., 2001).

In the 1970s, Hogan and Shprintzen advanced posterior pharyngeal flaps, leading to an increased success rate in the elimination of VPI. Hogan (1973) proposed a ‘lateral portal control’ flap to modulate the postoperative port size. In this flap, lateral ports exist on both sides of the pharyngeal flap to assist in drainage, nasal breathing, and nasal resonance. Using the pressure-flow studies of Warren and colleagues as a basis for lateral port size, Hogan placed a 4 mm diameter catheter through the lateral ports on either side of the flap to tailor the port size to the perception of nasal resonance (Sloan, 2000). Consistent with Warren’s aerodynamic data, Hogan advocated that the velopharyngeal opening be no greater than 4 mm in diameter because a larger gap would most likely result in hypernasal speech (Peterson-Falzone et al., 2001).

In 1979, Shprintzen advocated ‘tailor-made’ flaps, with the width of the flap determined by the degree of preoperative lateral pharyngeal wall adduction. According to Shprintzen, the base of the pharyngeal flap should be positioned at the site with the greatest level of lateral pharyngeal wall movement. In addition, Shprintzen recommends that a narrower flap be used with pronounced lateral pharyngeal wall movement, while a wider flap should be used with limited lateral pharyngeal wall movement (Sloan, 2000) Use of a narrow flap in individuals with limited preoperative lateral pharyngeal wall movement has the potential to increase lateral pharyngeal wall movement postoperatively (Karling et al., 1999).