Is bronchial wall imaging affected by temporal resolution? comparative evaluation at 140 and 75 ms in 90 patients

To evaluate the influence of temporal resolution (TR) on cardiogenic artefacts at the level of bronchial walls.

Ninety patients underwent a dual-source, single-energy chest CT examination enabling reconstruction of images with a TR of 75 ms (i.e., optimized TR) (Group 1) and 140 ms (i.e., standard TR) (Group 2). Cardiogenic artefacts were analyzed at the level of eight target bronchi, i.e., right (R) and left (L) B1, B5, B7, and B10 (total number of bronchi examined: n = 720).

Cardiogenic artefacts were significantly less frequent and less severe in Group 1 than in Group 2 (p < 0.0001) with the highest scores of discordant ratings for bronchi in close contact with cardiac cavities: RB5 (61/90; 68%); LB5 (66/90; 73%); LB7 (63/90; 70%). In Group 1, 78% (560/720) of bronchi showed no cardiac motion artefacts, whereas 22% of bronchi (160/720) showed artefacts rated as mild (152/160; 95%), moderate (7/160; 4%), and severe (1/160; 1%). In Group 2, 70% of bronchi (503/720) showed artefacts rated as mild (410/503; 82%), moderate (82/503; 16%), and severe (11/503; 2%).

At 75 ms, most bronchi can be depicted without cardiogenic artefacts.

• Quantitative CT helps analyze morphologic changes in COPD patients • Cardiogenic artefacts may hamper precise analysis of bronchial dimensions • Temporal resolution of CT acquisitions is an important parameter for bronchial imaging.