Predictive Value of 2D Radiographic Skeletal and Airway Measurements for Sleep Apnea in Children: A Cross-sectional Sleep Study on Airway Indicators and Diagnostic Cut-Off

OBJECTIVES: (a) To evaluate the link between 2D radiographic measurements of skeletal structures, airways and the likelihood of sleep apnea in children, and (b) to determine threshold values for predicting sleep apnea prior to diagnostic testing. MATERIALS AND METHODS: The study included 99 participants (7-17 years, median 11), referred to a sleep center for an overnight sleep study. Participants were divided into two age groups: 7-11 years and 12-17 years. CBCT scans were conducted within 30 days of the assessment. Lateral cephalograms were reconstructed for skeletal and airway analyses. Skeletal parameters included SNA, SNB, FMA, and SN-MP angles. Airway measurements included Retropalatal Airway space (RPA), PNS to adenoid point 1 (ad1), PNS to adenoid point 2 (ad2), and Adenoid to Nasopharynx (A/N) ratio). After verifying reliability, correlations between skeletal and airway measurements with the apnea-hypopnea index (AHI) were examined. ROC curves were generated, and sensitivity, specificity values were calculated to predict AHI levels of ≥5 and ≥10. RESULTS: Significant correlations were found between AHI and airway measurements of adenoid enlargement (RPA, PNS-ad1, PNS-ad2, and A/N ratio; p<0.05) in both groups. ROC curve analyses yielded significant predictive values, with proposed cut-off values for AHI ≥ 5 and AHI ≥ 10. No significant association was found between AHI and skeletal measurements (p>0.05). CONCLUSION: OSA prediction values were slightly better for 2D measurements, including the RPA, PNS-ad1, PNS-ad2, and A/N ratio, compared to previously reported 3D measurements. Two-dimensional radiographs, which offer equivalent or better predictive value with lower radiation exposure, are supported for OSA prediction, especially in younger children where adenoid enlargement is a key factor.