Comparison of Pharyngeal Airway Dimensions Between Nonsyndromic Cleft Lip and Palate Patients and Healthy Controls: A Systematic Review and Meta-Analysis

Objective This study aimed to evaluate the dimensions of pharyngeal airways among nonsyndromic cleft lip and palate (CLP) patients, comparing them with a healthy control group. Design Systematic review and meta-analysis. Patients and Exposures Patients with CLP. Comparison Patients without CLP. Main Outcome Measures Primary outcomes included the volume of different pharyngeal sections, total pharyngeal airway volume, and the minimum cross-sectional area of the pharynx. Secondary outcomes were to assess the effect of cleft type, age, and sex on pharyngeal airways. Results A comprehensive search of MEDLINE, Web of Science, EMBASE, Scopus, and Cochrane's CENTRAL (up to August 2023) identified 39 clinical studies meeting PECO criteria, with their risk of bias assessed using the Risk of Bias in Non-randomized Studies of Exposure tool. Of these, 33 were included in a random-effects inverse variance meta-analysis. The results indicated that nonsyndromic CLP patients demonstrated a significant reduction in the volumes of total pharyngeal airway ( P = .01), velopharynx ( P < .001), and oropharynx ( P < .001) compared to healthy individuals. No significant differences were observed between groups regarding nasopharynx ( P = .60) and hypopharynx ( P = .36) regions. The minimum cross-sectional area was significantly smaller in CLP patients compared to healthy individuals ( P = .02). The cleft type, age, and sex showed no significant effects on the extent of dimension reduction in pharyngeal airways ( P > .05). Conclusion The pharyngeal airway dimensions, particularly in the middle sections (velopharynx and oropharynx), are significantly reduced in nonsyndromic CLP patients when compared to the healthy controls. Variations in CLP type, patient age, and sex do not significantly influence this decrease in dimensions.