Velopharyngeal Surgery: A Prospective Randomized Study of Pharyngeal Flaps and Sphincter Pharyngoplasties

Antonio Ysunza, M.D., Sc.D., Ma. Carmen Pamplona, M.A., Elena Ramírez, B.A., Fernando Molina, M.D., Mario Mendoza, M.D., and Andres Silva, M.D. Mexico City, Mexico

Residual velopharyngeal insufficiency after palatal re- normalities of the velopharyngeal sphincter in- pair varies from 10 to 20 percent in most centers. Sec- volving the velum and/or pharyngeal walls. Hy- ondary velopharyngeal surgery to correct residual velo- pharyngeal insufficiency in patients with cleft palate is a pernasality is the signature characteristic of topic frequently discussed in the medical literature. Sev- persons with cleft palate. This disorder is diag- eral authors have reported that varying the operative ap- nosed efficiently through a careful clinical ex- proach according to the findings of videonasopharyngos- amination and with the aid of procedures such copy and multiview videofluoroscopy significantly as videonasopharyngoscopy and videofluoros- improved the success of velopharyngeal surgery. This ar- 1–3 ticle compares two surgical techniques for correcting re- copy. In our population, cleft palate occurs sidual velopharyngeal insufficiency, namely pharyngeal in approximately one in every 750 human flap and sphincter pharyngoplasty. Both techniques were births, making it one of the most common carefully planned according to the findings of videona- congenital malformations.4 sopharyngoscopy and multiview videofluoroscopy. Fifty patients with cleft palate and residual velopharyn- Surgical closure of the palatal cleft does not geal insufficiency were randomly divided into two groups: always result in a velopharyngeal port capable 25 in group 1 and 25 in group 2. Patients in group 1 were of supporting normal speech. Residual velo- operated on by using a customized pharyngeal flap ac- pharyngeal insufficiency is considered when cording to the findings of videonasopharyngoscopy and palatal repair is unsuccessful in providing com- multiview videofluoroscopy in each case. Those in group 2 received a sphincter pharyngoplasty also customized plete closure of the velopharyngeal sphincter 2,4–6 according to the findings of videonasopharyngoscopy and during speech. Residual velopharyngeal in- multiview videofluoroscopy. The median age of the pa- sufficiency varies from 10 to 20 percent in most tients in both groups was not significantly different (p Ͼ institutions. In our center, 650 patients with 0.5). The frequency of residual velopharyngeal insuffi- cleft palate were operated on between 1995 ciency after the individualized velopharyngeal surgery was not significantly different between the patient groups (12 and 2000. Residual velopharyngeal insuffi- percent versus 16 percent; p Ͼ 0.05). ciency was demonstrated in 71 (11 percent) of It seems that customized pharyngeal flaps and these patients.4 Secondary velopharyngeal sur- sphincter pharyngoplasties performed according to gery to correct velopharyngeal insufficiency in the findings of videonasopharyngoscopy and multiview videofluoroscopy are safe and reliable procedures for cleft palate patients with residual velopharyn- treating residual velopharyngeal insufficiency in cleft geal insufficiency is a topic frequently dis- palate patients. (Plast. Reconstr. Surg. 110: 1401, 2002.) cussed in the medical literature.4,7–12 Several reports have suggested that there cannot be one single operative approach to velopharyn- Velopharyngeal insufficiency refers to exces- geal insufficiency because velopharyngeal sive nasal resonance or hypernasality during physiology varies so remarkably from one indi- speech as the consequence of anatomical ab- vidual to another. Thus, a single operation is

From the Cleft Palate Clinic, Hospital Gea Gonzalez; and the Audiology and Phoniatrics Department, Hospital General de México. Received for publication November 2, 2001; revised February 26, 2002. DOI: 10.1097/01.PRS.0000029349.16221.FB 1401 1402 PLASTIC AND RECONSTRUCTIVE SURGERY, November 2002 not likely to correct all cases of velopharyngeal associated with velopharyngeal insufficiency re- insufficiency because closure defects at the quires speech therapy because of the dysfunc- velopharyngeal sphincter have been noted to tion not only of the velopharyngeal sphincter vary in size, position, shape, and consistency but also of the entire vocal tract.5,19–22 There- between individuals presenting with velopha- fore, articulation therapy before individualized ryngeal insufficiency.4,7,10,12 Videonasopharyn- velopharyngeal surgery is suggested to attempt goscopy and multiview videofluoroscopy pro- to increase the movements of the velopharyn- vide visualization of the velopharyngeal geal sphincter and thus reduce the degree of sphincter during speech. These procedures nasal obstruction necessary to eliminate velo- provide the best assessments to help plan and pharyngeal insufficiency.5,10,20 Moreover, at the direct the optimal treatment of velopharyngeal end of the operation articulation will be nor- insufficiency.1,2,4,12 Furthermore, several au- mal or nearly normal, so the postoperative re- thors have reported that varying the operative sult can be appreciated almost immediately. approach according to the findings of videona- Even if surgery corrects velopharyngeal insuffi- sopharyngoscopy and multiview videofluoros- ciency before the elimination of compensatory copy significantly improved the success of velo- articulation disorder, little change in speech is pharyngeal surgery.4,7,10,11 noticeable and it remains largely unintelligi- The goal in treating velopharyngeal insuffi- ble. Although patients and parents can be ciency is to restore a functional seal between counseled that speech therapy will still be nec- the nasopharynx and oropharynx so that nor- essary, at our center we believe that the largest mal speech articulation occurs. Several options trauma to the patient (i.e., surgery) should be are available. Individualized velopharyngeal saved for last and should result in a noticeable surgery is often performed when palatal clo- and important change in speech.5,10 sure fails to completely correct velopharyngeal This article compares two surgical tech- insufficiency and residual velopharyngeal in- niques for correcting residual velopharyngeal sufficiency persists. Individualized surgery in- insufficiency: pharyngeal flap and sphincter cludes customized pharyngeal flaps and pharyngoplasty. Both procedures were care- sphincter pharyngoplasties performed accord- fully planned according to the findings of ing to the findings of videonasopharyngoscopy videonasopharyngoscopy and multiview video- and multiview videofluoroscopy, as reported fluoroscopy. The size and form of the gap, previously.4,10,12,13 Pharyngeal flap is the main- lateral pharyngeal wall motion, and level of stay of surgical therapy for velopharyngeal in- maximum displacement of the velopharyngeal sufficiency in many facilities. Multiple modifi- sphincter were considered as criteria for indi- cations have been developed in an effort to vidualizing the surgical procedure. However, optimize speech outcome. In general, most before surgical planning, one of the two tech- centers have reported resolution of velopha- niques was selected randomly in each case. ryngeal insufficiency in 80 to 90 percent of patients undergoing customized pharyngeal PATIENTS AND METHODS flap operations.4,10,13,14 Sphincter pharyngo- The sample size was calculated at an alpha 95 plasty is another surgical procedure frequently percent confidence interval and a beta power used for correcting residual velopharyngeal in- of 80 percent for a comparative study of the sufficiency. This procedure can be also two treatment groups. The frequency of post- planned according to the specific findings of operative velopharyngeal insufficiency after in- the velopharyngeal sphincter in each case. The dividualized velopharyngeal surgery in cleft success rate for correcting velopharyngeal in- palate cases during 4 previous years at the cleft sufficiency with especially designed sphincter palate clinic was considered. We aimed to de- pharyngoplasty varies from 80 to 90 tect a 20 percent difference in proportion. percent.12,15–18 These data indicated at least 23 patients for Normality of the final speech results in all inclusion in each treatment group. A prospec- patients with velopharyngeal insufficiency de- tive study was completed of patients diagnosed pends on articulation as much as on normal with residual velopharyngeal insufficiency after resonance balance. Nasal resonance is cor- unilateral cleft lip and palate had been surgi- rected by physical management of the velopha- cally repaired at the cleft palate clinic of the ryngeal sphincter (surgery or prosthetic appli- Hospital Gea Gonzalez in Mexico City. All pa- ances). Compensatory articulation disorder tients diagnosed with residual velopharyngeal Vol. 110, No. 6 / VELOPHARYNGEAL SURGERY 1403 insufficiency from January of 1995 to Decem- sufficiency and associated compensatory artic- ber of 2000 were studied. During this period, ulation disorder, as demonstrated by phono- 359 patients who presented with a repaired logic assessment, videonasopharyngoscopy, unilateral cleft lip and palate at our clinic were and multiview videofluoroscopy. These pa- evaluated. The protocol was approved by the tients received speech therapy according to the research and bioethics committee of the hos- guidelines reported previously, including pho- pital. All parents and legal guardians were nologic approach and whole language inter- counseled before the patients were included in vention.23,25 Speech therapy was continued un- the study group. The study methods and surgi- til placement of articulation was adequate, cal procedures were carefully explained to all even when hypernasality was present. At the parents and legal guardians. We were espe- end of the speech intervention, all patients cially careful to point out that the surgical ap- were independently examined by two speech proach would be carefully planned according pathologists with 10 years of experience in eval- to the findings of videonasopharyngoscopy and uating and treating patients with cleft palate. multiview videofluoroscopy in each case, re- The patients did not continue the study proto- gardless of the random selection of one of the col until both pathologists were convinced that two surgical procedures. The goal was to the compensatory articulation disorder had achieve the best possible result with the surgi- been corrected, at least during the production cal technique assigned to each case. The par- of selected speech samples, which are routinely ents and legal guardians of all selected patients used in our center.23,25 Total time of speech agreed to participate in the study. intervention was considered to be the time To qualify for the subject group for this from onset of therapy until normalization of study, the patients had to meet the following placement of articulation, even when hyperna- criteria: sality was present. After the speech interven- tion, the 20 patients underwent additional 1. a diagnosis of nonsyndromic unilateral cleft videonasopharyngoscopy and multiview video- lip and palate with no other medical fluoroscopy to record data of the velopharyn- condition; geal sphincter without the influence of com- 2. velopharyngeal insufficiency with or with- pensatory articulation disorder. Finally, these out compensatory articulation disorder as 20 cases were included within the whole study demonstrated by phoniatric assessment, group of 50 cases. videonasopharyngoscopy, and multiview It should be noted that although surgery was videofluoroscopy; indicated in these 20 patients at the time in 3. chronologic age between 4 and 8 years at which placement of articulation had been cor- the time of selection for the study; rected, it was carefully explained to all parents 4. normal hearing as demonstrated by conven- that speech therapy must be continued until tional pure-tone audiometry; articulation was completely corrected during 5. language development within reference spontaneous connected speech. limits as demonstrated by the Speech Dis- For the surgical treatment, the patients were crimination Score model23; randomized to either the pharyngeal flap 6. absence of postoperative fistulas; group or the sphincter pharyngoplasty group 7. cleft palate width of grades I or II24; using block randomization. The precise 8. palatal repair of the unilateral cleft lip and method of block randomization was blind to palate performed according to the surgical the surgeons and involved balancing the num- routine of the cleft palate clinic (i.e., surgi- ber of patients recruited to both groups of the cal repair of the lip and primary palate be- study, after every 20 recruits. This level of block tween 1 and 3 months of age, and surgical randomization ensured that if the study had repair of the secondary palate before 8 been stopped early, there would have been months of age with a minimal-incision almost exactly the same number of operations. palatopharyngoplasty).24 The blinding ensured that the surgeons did A total of 50 patients met the criteria for not obtain sufficient knowledge to enable inclusion in the study group. Twenty-seven pa- them to second-guess the allocation of the next tients with residual velopharyngeal insuffi- recruit.26 ciency did not meet the criteria for this study. Twenty-five patients were included in group Twenty patients showed velopharyngeal in- 1 and 25 in group 2. Patients in group 1 were 1404 PLASTIC AND RECONSTRUCTIVE SURGERY, November 2002 operated on by using a customized pharyngeal RESULTS flap according to the findings of videonasopha- The age of the patients in group 1 (n ϭ 25) ryngoscopy and multiview videofluoroscopy in ranged from 4 years to 7 years, 7 months (me- each case. Those in group 2 received a sphinc- dian: 4 years, 7 months). In group 2 (n ϭ 25), ter pharyngoplasty also customized according ages ranged from 4 years to 7 years, 4 months to the findings of videonasopharyngoscopy and (median: 4 years, 5 months). A Mann-Whitney multiview videofluoroscopy. As previously re- rank sum test revealed a nonsignificant differ- ported, the size and form of the gap, lateral ence in age between both groups (p Ͼ 0.5). pharyngeal wall motion, and level of maximum The total time of speech intervention in the displacement of the velopharyngeal sphincter 20 patients who presented with velopharyngeal were considered as criteria for individualizing insufficiency and compensatory articulation the surgical procedure; i. e., width, location, disorder ranged from 11 to 41 months (mean and level of insertion of the pharyngeal flap or Ϯ SD, 20.2 Ϯ 9.5). Although 92 percent of the the lateral flaps of the sphincter pharyngo- patients demonstrated an improvement in plasty.4,10,12,13 All procedures were performed velopharyngeal movements and a reduction in by the same team, which included two of the gap size after correction of compensatory artic- current authors. ulation, in none of the patients was velopha- Four months after the surgical procedures, ryngeal insufficiency corrected by speech ther- all patients underwent additional phoniatric evaluation. A blind procedure was used apy. Moreover, the form of the gap at the whereby all analyses were independently con- velopharyngeal insufficiency was not modified ducted by two speech pathologists with 10 years by speech therapy. The opinions of the exam- of experience in evaluating and treating cleft iners for the preoperative videonasopharyngos- palate patients in our center. Only perceptual copy and multiview videofluoroscopy coin- evaluations were used to keep the examiners cided in most of the cases regarding the blind to the surgical procedures that had been presence or absence (yes or no) of velopharyn- performed. Postoperative videonasopharyngos- geal insufficiency in each case. A kappa statistic copy and multiview videofluoroscopy were also of 0.90 was found between the pair of examin- performed 4 months after the surgical proce- ers analyzing videonasopharyngoscopies. How- ever, it should be noted that a kappa statistic of dures. All of these evaluations were indepen- Ͻ dently analyzed by two phoniatrists who had 10 0.75 was found when the size of the gap was years of experience in performing and assess- assessed by the pair of examiners. This value ing these procedures in our center. The pres- denoted a nonsignificant reproducibility. ence or absence of velopharyngeal insuffi- Closure patterns of the velopharyngeal ciency, and the size and form of the defect at sphincter during speech were evenly distrib- the velopharyngeal sphincter during speech, uted between the two treatment groups. Forty- were determined. Concordance between each five percent of the patients showed a coronal pair of examiners was evaluated using the pattern, 47 percent showed a circular pattern, kappa statistic; kappa Ͼ0.75 was considered as and 8 percent showed Passavant’s ridge. The denoting excellent reproducibility.26 When dif- gap size of the velopharyngeal closure during ferences occurred, each case was discussed by speech as observed preoperatively by videona- the examiners until an agreement was reached. sopharyngoscopy and multiview videofluoros- The results from both groups of patients copy was not significantly different between the were compared. Age was considered as a one- groups (28.25 Ϯ 7.82 percent in group 1; 29.25 dimensional variable and was analyzed by a Ϯ 6.34 percent in group 2; p Ͼ 0.5). Mann-Whitney rank sum test. Another dimen- A kappa statistic of 0.90 was found between sional variable was the size of the gap as ob- the pair of examiners analyzing postoperative served by videonasopharyngoscopy and multi- phoniatric assessment. When postoperative re- view videofluoroscopy, which was analyzed by sults of the videonasopharyngoscopy and mul- Student’s t test. Velopharyngeal insufficiency tiview videofluoroscopy were examined, a was considered as a binary variable (yes or no) kappa statistic of 0.90 was found between the and was analyzed with a Fisher’s exact t test. For pair of examiners regarding the presence or each variable, an alpha value of 0.05 was se- absence (yes or no) of velopharyngeal insuffi- lected for considering the results as stochasti- ciency in each case. cally significant.27 Both examiners noted that all the patients Vol. 110, No. 6 / VELOPHARYNGEAL SURGERY 1405 who presented with postoperative velopharyn- way obstruction were found in any of the pa- geal insufficiency showed only bubbling at the tients operated on in this study. velopharyngeal sphincter during speech, but Surgical management of velopharyngeal no gap could be defined (i.e., a “pinhole” gap). insufficiency presents the challenge of bal- Thus, according to previous reports, all of ancing acceptable nasal resonance and nasal these patients were recorded as having a defect obstruction. In this study, the surgical result of 10 percent.1 was considered a success when oronasal res- The success rate for correcting velopharyn- onance was normal and nasal air escape was geal insufficiency after the surgical procedures absent; residual velopharyngeal insuffi- was not significantly different between the ciency, however mild, was counted as such. groups (p Ͼ 0.05). Three patients (12 percent) We believe this to be a less biased way of from group 1 and four (16 percent) from reporting results. In this study, patients un- group 2 demonstrated postoperative velopha- dergoing either procedure were at risk for ryngeal insufficiency. Complete closure of the obstructive airway symptoms. velopharyngeal sphincter was achieved in 22 None of the parents reported that a child patients (88 percent) from group 1 and in 21 had obstructive sleep apnea after surgery. As (84 percent) from group 2 (Table I). noted earlier, in our cleft palate clinic all pa- tients who present with residual velopharyn- geal insufficiency after palatal repair routinely DISCUSSION undergo videonasopharyngoscopy and multiv- The results of this study suggest that the iew videofluoroscopy. When the risk of obstruc- frequency of velopharyngeal insufficiency was tion is detected, tonsillectomy is performed not significantly different when two methods of before velopharyngeal surgery, and/or naso- individualized velopharyngeal surgery were pharyngeal tubes are routinely used in the used. This study was undertaken to examine postoperative period.28 our experience with the sphincter pharyngo- The relatively small number of patients and plasty and pharyngeal flap procedures after the homogeneity29 of the sample included in our clinical experience indicated that similar this study do not allow definite conclusions. good results were being obtained with both With these limitations in mind, we believe we procedures. Individually customized pharyn- can comment about speech outcome in pa- geal flaps and sphincter pharyngoplasties, ac- tients undergoing pharyngeal flap and sphinc- cording to the findings of videonasopharyngos- ter pharyngoplasty at our institution. Reso- copy and multiview videofluoroscopy, seem to nance and speech outcomes seemed similarly be similarly useful in treating residual velopha- favorable after either a pharyngeal flap or a ryngeal insufficiency in patients with cleft sphincter pharyngoplasty. Thus, it seems ap- palate. propriate to approach residual velopharyngeal All patients operated on with these two pro- insufficiency after palatal repair with a care- cedures showed only bubbling at the velopha- fully planned surgical procedure, individually ryngeal sphincter, with no defined gap postop- customized for each case according to the find- eratively. Thus, the size of the gaps was ings of videonasopharyngoscopy and multiview reduced in all cases. No complications such as videofluoroscopy. Furthermore, regardless of postoperative bleeding, fistulas, or upper air- the selection of a pharyngeal flap or a sphinc- ter pharyngoplasty, it seems that the planning TABLE I of the surgical procedure to match the postop- Postoperative Frequency of Velopharyngeal Insufficiency erative structure to the preoperative move- ments seen in the velopharyngeal sphinc- ter4,7,10,11 is one of the most important aspects Velopharyngeal Complete Insufficiency Closure of this surgery. Group* n % n % Total (n) The variability of velopharyngeal valving in 1 3 12 22 88 25 patients with velopharyngeal insufficiency 2 4 16 21 84 25 stresses the importance of observing the com- Total 7 43 50 ponent movements of velopharyngeal closure. Ͼ p 0.05 Operations to correct velopharyngeal insuffi- * A Fisher’s exact test demonstrated that the frequency was not significantly different, independently of the surgical procedure used in each group of ciency provide tissue obturators (pharyngeal patients (group 1, pharyngeal flap; group 2, sphincter pharyngoplasty). flap or lateral flaps of the sphincter pharyngo- 1406 PLASTIC AND RECONSTRUCTIVE SURGERY, November 2002 plasty) that will close the gaps during speech. 7. Shprintzen, R. J., Lewin, M. L., and Croft, C. B. A com- The tissue obturator must be placed correctly. prehensive study of pharyngeal flap surgery: Tailor made flaps. Cleft Palate J. 16: 46, 1979. In our center, when surgery is indicated, the 8. Argamaso, R. V. Physical management of velopharyn- surgeon, phoniatrist, and speech pathologist geal incompetence. J. Childhood Comun. Dis. 10: 67, review the studies immediately before treat- 1986. ment. The size and shape of the gap are con- 9. Argamaso, R. V., Shprintzen, R. J., Strauch, B., et al. The sidered for determining the width of the pha- role of lateral pharyngeal wall motion in pharyngeal flap surgery. Plast. Reconstr. Surg. 66: 214, 1980. ryngeal flap or the lateral flaps of the sphincter 10. Shprintzen, R. J. Surgery for speech: The planning of pharyngoplasty. The symmetry of displacement operations for velopharyngeal insufficiency with is considered for deciding if the flap should be emphasis on the preoperative assessment of both skewed or if the width of one of the lateral flaps pharyngeal physiology and articulation. In M. Y. should be increased. The contour of the lateral Ferguson (Ed.), Proceedings of the British Craniofacial Society. Manchester: University of Manchester Press, pharyngeal walls and velum, which refers to the 1988. vertical extent of movement as observed by the 11. Peat, B. G., Albery, E. H., Jones, K., et al. Tailoring frontal and lateral projections of the videofluo- velopharyngeal surgery: The influence of etiology roscopy, should also be considered. The height and type of operation. Plast. Reconstr. Surg. 93: 948, of the pharyngeal flap or the lateral flaps is a 1994. 12. Ysunza, A., Pamplona, M., and Molina, F. Velopharyn- key element. The tissue should be placed at the geal motion after sphincter pharyngoplasty: A video- level of maximum movement. nasopharyngoscopic and electromyographic study. In conclusion, we suggest varying the surgi- Plast. Reconstr. Surg. 104: 905, 1999. cal approach to velopharyngeal insufficiency, 13. Shprintzen, R. J. Cleft Palate Management: A Multidisci- using the pharyngeal flap or sphincter pharyn- plinary Approach. St. Louis: Mosby, 1996. 14. Morris, H. L., Bardach, J., Jones, D., et al. Clinical re- goplasty according to the relative contribution sults of pharyngeal flap surgery: The Iowa experience. of the movements of the velum, lateral pharyn- Plast. Reconstr. Surg. 95: 652, 1995. geal walls, posterior pharyngeal wall, and level 15. Riski, J. E., Ruff, G. L., Georgiade, G. S., et al. Evaluation of maximum displacement of the velopharyn- of failed sphincter pharyngoplasties. Ann. Plast. Surg. geal sphincter. Surgeons who treat velopharyn- 28: 545, 1992. 16. Riski, J. E., Ruff, G. L., Georgiade, G. S., et al. Evaluation geal insufficiency must critically assess their of the sphincter pharyngoplasty. Cleft Palate-Craniofac. own outcomes to develop an appropriate treat- J. 29: 254, 1992. ment algorithm. 17. Witt, P. D., D’Antonio, L. L., Zimmerman, G. J., and Dr. Antonio Ysunza Marsh, J. L. Sphincter pharyngoplasty: A preop- Hospital Gea Gonzalez erative and postoperative analysis of perceptual speech characteristics and endoscopic studies of 4800 Calzada Tlalpan velopharyngeal function. Plast. Reconstr. Surg. 93: México D. F. 14000 1154, 1994. [email protected] 18. Witt, P. D., Marsh, J. L., Arlis, H., et al. Quantification of dynamic velopharyngeal port excursion following REFERENCES sphincter pharyngoplasty. Plast. Reconstr. Surg. 101: 1. Golding-Kushner, K. J., Argamaso, R. V., Cotton, R. T., et 1205, 1998. al. Standardization for the reporting of nasopharyn- 19. Trost-Cardamone, J. E. Effects of velopharyngeal in- goscopy and multiview videofluoroscopy: A report competence on speech. J. Child Commun. Dis. 10: 31, from an International Working Group. Cleft Palate 1986. J. 27: 337, 1990. 20. Ysunza, A., Pamplona, C., and Toledo, E. Change in 2. Shprintzen, R. J., and Golding-Kushner, K. J. Evaluation velopharyngeal valving after speech therapy in cleft of velopharyngeal insufficiency. Otolaryngol. Clin. palate patients: A videonasopharyngoscopic and mul- North Am. 22: 519, 1989. tiview videofluoroscopic study. Int. J. Pediatr. Otorhino- 3. Trost-Cardamone, J. E. Coming to terms with VPI: A laryngol. 24: 45, 1992. response to Loney and Bloem. Cleft Palate J. 26: 68, 21. Ysunza, A., Pamplona, M., Femat, T., et al. Videonaso- 1989. pharyngoscopy as an instrument for visual biofeed- 4. Ysunza, A., Pamplona, M., Mendoza, M., et al. Surgical back during speech in cleft palate patients. Int. J. Pe- treatment of submucous cleft palate: A comparative diatr. Otorhinolaryngol. 41: 291, 1997. trial of two modalities for palatal closure. Plast. Recon- 22. Ysunza, A., Pamplona, M. C., Mendoza, M., et al. Speech str. Surg. 107: 9, 2001. outcome and maxillary growth in patients with uni- 5. Pamplona, M., Ysunza, A., Guerrero, M., et al. Surgical lateral complete cleft lip/palate operated on at 6 ver- correction of velopharyngeal insufficiency with and sus 12 months of age. Plast. Reconstr. Surg. 102: 675, without compensatory articulation. Int. J. Pediatr. Oto- 1998. rhinolaryngol. 34: 53, 1996. 23. Pamplona, M. C., Ysunza, A., Gonzalez, M., et al. Lin- 6. Kuehn, D. P., and Moller, K. T. Speech and language guistic development in cleft palate patients with and issues in the cleft palate population: The state of the without compensatory articulation disorder. Int. J. Pe- art. Cleft Palate-Craniofac. J. 37: 348, 2000. diatr. Otorhinolaryngol. 54: 81, 2000. Vol. 110, No. 6 / VELOPHARYNGEAL SURGERY 1407

24. Mendoza, M., Molina, F., Azzolini, C., and Ysunza Rivera, 26. Rosner, B. Fundamentals of Biostatistics, 5th Ed. Pacific A. Minimal incision palatopharyngoplasty: A prelim- Grove, Calif.: Duxbury, 2000. inary report. Scand. J. Plast. Reconstr. Surg. Hand Surg. 27. Feinstein, A. Multivariate Analysis. New Haven: Yale Uni- 28: 199, 1994. versity Press, 1996. 25. Pamplona, M. C., Ysunza, A., and Espinoza, J. A 28. Ysunza, A., García-Velasco, M., García-García, M., et al. comparative trial of two modalities of speech inter- Obstructive sleep apnea secondary to surgery for velo- vention for compensatory articulation in cleft pal- pharyngeal insufficiency. Cleft Palate-Craniofac. J. 30: ate children, phonologic approach versus articula- 387, 1993. tory approach. Int. J. Pediatr. Otorhinolaryngol. 49: 29. Shprintzen, R. J. Fallibility of clinical research. Cleft Pal- 21, 1999. ate-Craniofac. J. 28: 136, 1991.