Airflow of the Two-Port Velopharyngeal Closure: Study Using Computational Fluid Dynamics

Buccal Myomucosal Flap Repair for Velopharyngeal Dysfunction

BACKGROUND

Velopharyngeal dysfunction (VPD) is the incomplete separation of the nasal and oral cavities during speech sound production that can persist following primary palatoplasty. Surgical technique used in management of VPD (palatal re-repair versus pharyngeal flap or sphincter pharyngoplasty) is often dictated by the preoperative velar closing ratio and closure pattern. Recently, buccal flaps have increased in popularity in management of VPD. Here, the authors investigate the effectiveness of buccal myomucosal flaps in the treatment of VPD.

METHODS

A retrospective review was performed of all patients undergoing secondary palatoplasty with buccal flaps at a single center between 2016 and 2021. Preoperative and postoperative speech outcomes were compared. Speech assessments included perceptual examinations, graded on a four-point scale of hypernasality, and speech videofluoroscopy, from which the velar closing ratio was obtained.

RESULTS

A total of 25 patients underwent buccal myomucosal flap procedures for VPD at a median of 7.1 years after primary palatoplasty. Patients had significantly increased velar closing postoperatively (95% versus 50%; P < 0.001) and improved speech scores ( P < 0.001). Three patients (12%) had continued hypernasality postoperatively. There were no occurrences of obstructive sleep apnea.

CONCLUSIONS

Treatment of VPD with buccal myomucosal flaps leads to improved speech outcomes without the risk of obstructive sleep apnea. Traditionally, palatal re-repair techniques have been used for smaller preoperative velopharyngeal gaps; however, the addition of buccal flaps allows for anatomical velar muscle correction for patients with a larger preoperative velopharyngeal gap.

CLINICAL QUESTION/LEVEL OF EVIDENCE

Therapeutic, IV.

ChatGPT for shaping the future of dentistry: the potential of multi-modal large language model

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Inspiration After Posterior Pharyngeal Flap Palatoplasty: A Preliminary Study Using Computational Fluid Dynamic Analysis

Posterior pharyngeal flap palatoplasty (PPF) is one of the most commonly used surgical procedures to correct speech, especially for patients suffering from velopharyngeal insufficiency (VPI). During PPF, surgeons use the catheter to control the lateral velopharyngeal port on each side. Airway obstruction and sleep apnea are common after PPF. To understand the air dynamics of the upper airway after PPF, we used computational fluid dynamics (CFD) to demonstrate the airflow. In our previous study, we have revealed the expiration process of the upper airway after PPF and shown the features of how PPF successfully restores the oral pressure for speech. In this study, we focus on examining the inspiration process. Normal airway structures were included. For the normal velopharyngeal structure, one cylinder was applied to each model. For recapitulating the velopharyngeal structure after PPF, two cylinders were used in each model. The ports for borderline/inadequate closure, which can help the oral cavity get the required pressure, were chosen for this study. A real-time CFD simulation was used to capture the airflow through the ports. We found that the airflow dynamics of the upper airway's inspiration were dependent on the velopharyngeal structure. Although the airflow patterns were similar, the velocities between one-port and two-port structures were different, which explained why patients after PPF breathed harder than before and suggested that the one-port structure might be a better choice for secondary VPI reconstruction based on the CFD analyses.