The early and accurate detection of bronchiectasis is paramount to initiate treatment and to reverse early disease. The diagnosis of bronchiectasis is based upon the pathognomonic radiological finding of an increased broncho-arterial ratio on chest CT scans. Adult studies performed several decades ago derived a diagnostic threshold of 1.0. However, this finding is now outdated given the development of new CT protocols and applied to all ages, despite differences in broncho-arterial ratios between young children and the elderly. The Team has advocated using paediatric-specific criteria (a threshold value of broncho-arterial ratio<0.8), although this is not universally accepted.

Aim

To validate a paediatric broncho-arterial ratio to define a paediatric diagnostic threshold value.

Approach

Using existing resources, radiological images from 100 children without cardiac or lung disease will be assessed. Inner and outer wall broncho-arterial ratio and wall thickness will be measured, and a broncho-arterial ratio threshold confirmed.