Deep learning-based automatic adenoid segmentation and a novel volume-based index for adenoid hypertrophy assessment
Xin Zhang1,2, Yuanyuan Li3,2, Xueying Wu4,2
1Department of Orthodontics, Shanghai Stomatological Hospital, School of Stomatology, Fudan University, Shanghai, China.
BMC Oral Health
|January 16, 2026
Summary
A new deep learning method accurately measures adenoid volume using cone-beam computed tomography (CBCT). The Three-Dimensional Adenoidal-Nasopharyngeal Ratio (3D-AN) aids in early detection of pediatric obstructive sleep apnea (OSA).
Area of Science:
- Medical Imaging
- Artificial Intelligence in Medicine
- Pediatric Sleep Medicine
Background:
- Adenoid hypertrophy is a primary cause of pediatric obstructive sleep apnea (OSA), impacting cognitive and craniofacial development.
- Accurate assessment of adenoid volume and nasopharyngeal obstruction is crucial for timely intervention.
- Current methods for quantifying airway obstruction lack precision in three dimensions.
Purpose of the Study:
- To develop a deep learning-based method for accurate adenoid segmentation from CBCT scans.
- To establish a novel quantitative index, the Three-Dimensional Adenoidal-Nasopharyngeal Ratio (3D-AN), for assessing nasopharyngeal airway obstruction.
- To investigate the correlation between the 3D-AN and pediatric OSA.
Main Methods:
- A SegResNet-based deep learning model was trained on CBCT scans from pediatric OSA patients to segment adenoids.
- Adenoid volume was determined by predicting postoperative airway morphology from preoperative scans.
- The 3D-AN ratio was calculated using adenoid and nasopharyngeal volumes, and its correlation with OSA was analyzed using polysomnography data.
Main Results:
- The adenoid segmentation model achieved a Dice similarity coefficient of 0.88 and a relative volume error of 0.09.
- A 3D-AN ratio below 0.18 showed no significant correlation with pediatric OSA.
- A 3D-AN ratio above 0.18 demonstrated a significant correlation with pediatric OSA (r=0.56, P<0.01).
Conclusions:
- An automated deep learning method provides accurate adenoid segmentation from CBCT.
- The novel 3D-AN ratio shows potential for early detection of adenoid-related airway obstruction.
- This approach can support future research and clinical management of pediatric airway obstruction.


