Table 1—

Characteristics of an ideal quantitative airway imaging tool

Readily repeatable measurements in airway sizes spanning the tracheobronchial tree
Automated measurement of dimensions (e.g. lumen area and wall thickness)
Correction of angle of orientation, ensuring airways are measured in cross section
Favourable inter-observer and intra-observer repeatability
Safe for long-term and repeated use (minimal levels of ionising radiation)
Measurements easily repeated before and after interventions
Dynamic acquisition so that functional, as well as structural, airway information is available
Ability to segment the airway into a three-dimensional view
Provide detail of the subsurface architecture