Investigation of relationship between neck anteroposterior-transvers diameters and trachea anteroposterior-transvers diameters based on CT scans

Year 2026, Volume: 8 Issue: 2, 319 - 323, 10.03.2026

Abdullah Belada , Cansu Şengül , Mehmet Ali Özel , İlhan Ünlü , Buğra Subaşı , Ender Güçlü , Ayşe Nur Belada , Ömer Önbaş

https://izlik.org/JA27SF79BS

Abstract

Aims: The tracheal diameter may be influenced by external anatomical characteristics, and accurate estimation of airway dimensions is important for procedural planning. This study aimed to evaluate the anatomical relationship between neck and tracheal dimensions using radiological measurements in the anteroposterior (AP) and transverse (TR) planes.
Methods: A total of 180 adult patients were retrospectively included in the study. The AP and TR diameters of the first tracheal ring and the AP and TR diameters of the neck at the level of the cricoid cartilage were measured on computed tomography (CT) images. Body mass index was calculated from recorded height and weight data. Correlation analyses and multiple linear regression models adjusted for age, sex, and body mass index were performed.
Results: Significant sex-related differences were observed in tracheal AP and TR diameters (trachea AP: 19.97±2.10 mm vs. 16.32±1.87 mm; trachea TR: 20.00±1.67 mm vs. 16.14±1.69 mm; both p<0.001). Significant differences were also found in neck dimensions between males and females (neck AP: 141.56±14.64 mm vs. 123.79±20.41 mm; p<0.001; neck TR: 126.24±12.97 mm vs. 120.12±12.99 mm; p=0.002). Correlation analysis demonstrated statistically significant associations between tracheal and neck measurements. In multivariable regression analysis, neck AP diameter and sex were significantly associated with both tracheal AP and TR diameters.
Conclusion: Tracheal and neck dimensions measured on CT were statistically associated, with stronger relationships observed in AP measurements. However, the magnitude of these associations was limited, indicating that external neck measurements alone are insufficient for precise prediction of tracheal size. Neck measurements may serve as complementary anatomical indicators within a multifactorial airway assessment approach rather than as standalone predictors.

Keywords

Tracheal diameter , neck diameter , airway management

Ethical Statement

This product received ethical committee approval in 2023. There are no conflicts of interest among the authors.

Supporting Institution

The authors also declare that they did not receive any financial support for the study

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