Nasal airway resistance in patients with different degrees of operated unilateral cleft lip: Evaluation of ventilation in 112 patients

Objective: The aim of this study was to compare the nasal airway resistance between the cleft and non-cleft sides in operated unilateral cleft lip (UCL) patients with varying severities at birth, as well as to assess the differences in nasal airway resistance between UCL patients and healthy individuals.

Methods: This retrospective study was conducted on 112 UCL patients who have undergone primary lip reconstructions but not advanced surgeries as the study group and 20 healthy participants as the control group between February 2023 to March 2024. The study group patients were grouped based on the severity of their cleft lip at birth, divided into occult cleft lip group, incomplete cleft lip group, and complete cleft lip group. The anterior rhinomanometry was used to evaluate nasal resistance, including unilateral effective resistances during inspiration (Reffin), expiration (Reffex), and the entire breath (ReffT), as well as unilateral vertex resistance during inspiration (VRin) and expiration (VRex). The Kolmogorov-Smirnov test was used to assess normality. Paired t-tests were utilized to analyze the differences in nasal resistance between the healthy and affected sides within the same group of patients. Student's t-test was used to analyze the differences in nasal resistance among patients with different degrees of cleft lip. A p-value of <0.05 was considered statistically significant.

Results: The nasal resistances of the occult cleft and incomplete cleft lip groups showed no significant differences between the cleft and non-cleft sides, and were similar to the control group. However, in the complete cleft lip group, the cleft side nasal resistance was significantly higher than the non-cleft side and control group. Among the groups, the complete cleft lip group had significantly higher nasal resistances on the cleft side for Reffin, VRin, and ReffT compared to the occult cleft group.

Conclusion: Understanding the nasal resistance of different degrees of operated UCL patients can benefit clinical diagnosis and treatment. Patients with complete cleft lip have more severe nasal obstruction on the cleft side, with greater impact on inhalation than exhalation. For these patients, treatment by an otolaryngologist is recommended to improve nasal airflow.