[Role of remodeling of pharyngeal cavity in velopharyngoplasty for treating obstructive sleep apnea hypopnea syndrome and its related anatomic study].

Objective: To investigate a new velopharyngoplasty (VPP), including its anatomic character and its mechanism of remodeling of oral-pharynx cavity for treating obstructive sleep apnea hypopnea syndrome (OSAHS).

Methods: Two cases of soft palate were dissected in adult male cadavers. And the model of VPP was established to further observe its technical characteristics. A total of 85 OSAHS patients were studied by PSG. And all cases received velopharyngoplasty (VPP) and follow-ups. Ten cases were selected for CT scanning of palatal pharyngeal cavity and CT workstation was employed for imaging measurements.

Results: The measured parameters of pharyngeal palate included soft palate length, maximal thickness of soft palate, soft palate to posterior pharyngeal edge of free space, parapharyngeal space (distance between tonsils), uvula length, width of uvula base, velopharyngeal cross-sectional area and cross-sectional area of angina. All these parameters had a significantly difference between pre-operation and post-operation [(37.8 +/- 5.5) mm vs (27.0 +/- 4.1) mm, (13.3 +/- 2.2) mm vs (9.3 +/- 2.5) mm, (7.1 +/- 2.8) mm vs (10.3 +/- 1.7) mm, (45.2 +/- 25.5) mm(2) vs (135.3 +/- 26.4) mm(2), (2.0 +/- 21.8) mm(2) vs (208.4 +/- 15.9) mm(2)]; however there was no significant difference in retropharyngeal wall thickness [(6.8 +/- 2.9) mm vs (7.0 +/- 2.5) mm].

Conclusion: VPP remodels palatopharyngeal region through the design of incision, the management of pharyngopalatine arch tonsillectomy and the suture of laterapharynx mucisae. This surgical procedure can obviously upgrade the velum platinum, enlarge the oropharyngeal airway effectively. It is a significant modified-UPPP surgical technique.