Three-dimensional upper airway phenotyping and OSA severity: a CT-based study

Area of Science:

• Medical Imaging
• Pulmonology
• Anatomy

Background:

• Obstructive sleep apnea (OSA) involves recurrent upper airway collapse during sleep.
• While anatomical factors are crucial, the relationship between 3D upper airway dimensions and OSA severity is not fully understood, hindering personalized treatment strategies.

Purpose of the Study:

• To identify the most relevant 3D upper airway anatomical parameter correlating with obstructive sleep apnea (OSA) severity.
• To evaluate the potential of this parameter as a reliable imaging biomarker for OSA risk stratification.

Main Methods:

• 69 OSA patients underwent polysomnography and computed tomography (CT) scans.
• 3D upper airway segmentation and measurement of parameters including minimum cross-sectional area (MIN-CSA) and the ratio of total volume to MIN-CSA (TV-NP-OP/MIN-CSA).
• Statistical analyses including correlation, ROC, and logistic regression were used to assess associations with the apnea-hypopnea index (AHI).

Main Results:

• The TV-NP-OP/MIN-CSA ratio, termed "Anatomical Risk Index," strongly correlated with OSA severity (r=0.473, p<0.001).
• This index demonstrated good diagnostic performance for moderate-to-severe and severe OSA and was an independent predictor across BMI subgroups.
• Excellent measurement reliability (ICCs > 0.90) was observed, with no volumetric parameters showing significant correlation with AHI.

Conclusions:

• The TV-NP-OP/MIN-CSA ratio is a robust 3D anatomical parameter significantly associated with OSA severity.
• This CT-derived "Anatomical Risk Index" can serve as a valuable imaging biomarker for identifying high-risk OSA phenotypes and guiding personalized treatment.