Volumetric MRI Evaluation of Airway, Tongue, and Mandible in Different Skeletal Patterns: Does a Link to Obstructive Sleep Apnea Exist (OSA)?

ABSTRACT

Backgroun/Objectives: Craniofacial disharmony has been long debated as an important predisposing factor in the development and progression ofsleep-disordered breathing and OSA. The present study was aimed to determine and compare whether a direct correlation occurs between the airway volume, mandibular dimension, and tongue volume in different craniofacial growth patterns. The objectives were the 3D MR[ assessment and comparison ofairway volume, mandibular dimensions, and tongue volume in Class I normodivergent, Class II hyperdivergent, and OSA group. MATERIALS/METHODS: Study population included 45 patients (12-18 years). Soft tissue volume estimation for airway [oropharyngeal (OP), nasopharyngeal (NP)] and tongue was carried out using MRI and DICOM image processing software(Osirix@ v5.6).Mandibular dimensions were characterized on MR, and derivations were made using the Pythagoras theorem. Subsequently, 3D reconstructions were carried out. The mean and standard deviation were obtained. Kruskal-Wallis and Wilcoxon rank sum test were used. Multiple regression analysis was performed for OP and NP volumes using BMI, mandibular area, and tongue volume as predictors for the complete sample. RESULTS: It was found that in overall sample, mandibular length showed a positive correlation with OR NP and tongue volumes. For both OP and NP glossomandibular area, and tongue volume were found to be statistically significant predictors. CONCLUSIONS/IMPLICATIONS A direct correlation was confirmed between the airway volume, mandibular dimensions, and tongue volume in different craniofacial growth patterns. The present knowledge can be utilized on patients for treatment of reduced airway space using the derived formula for mandibular dimensions, and the regression equations can be used as a diagnostic aid in determining the OP and NP volume for any individual using 2D radiofraphs in orthodontics.