Relationship of Cricoid With the Right and Left Bronchial Diameters in the Pediatric Population Using Three-dimensional Imaging.

Understanding the relationship between cricoid and mainstem bronchi can provide to be a useful adjunct for lung isolation in children. The relationship between cricoid dimensions and the dimensions of main-stem bronchi (right and left) have been studied using 2 dimensional CT images and video-bronchoscopic images. The present study defines the volume-based relationship between the right main-stem bronchus (RMSB), left main-stem bronchus (LMSB) and the cricoid ring based on 3 dimensional CT derived images.

Methods: The three dimensional CT images of 35 children, younger than 8 years, undergoing radiological evaluation unrelated to airway symptomatology were examined. The children were evaluated during spontaneous ventilation without airway devices either during natural sleep or with sedation. The 3-dimensional images of the airway column were evaluated at the level of cricoid, right mainstem bronchus and left main-stem bronchus, volumes were calculated and comparisons made between these levels. Univariate and multivariate regression analysis was used to determine whether one or more of the variables (age, gender, height, weight and cricoid) had a predictable relationship to the RMSB and the LMSB diameter.