Box 1.

The ATS/ERS consensus statement for the diagnosis of IPF set out criteria for the optimal HRCT technique for evaluation of ILD¹

Optimal HRCT technique for evaluation of ILD
Non-contrast scans obtained on full inspiration without respiratory motion. Contiguous or non-contiguous axial scans with thin sections, reconstructed at ≤2 cm intervals. Reconstructed slice collimation ≤2 mm. High resolution reconstruction algorithm. Field of view to include lungs only. Expiratory scans are helpful to exclude lobular air trapping suggestive of hypersensitivity pneumonitis. Prone scans if dependent density obscures detail on supine images. Optional coronal and sagittal reconstructions if volumetric images are obtained.

Optimal HRCT technique for evaluation of ILD

Non-contrast scans obtained on full inspiration without respiratory motion.
Contiguous or non-contiguous axial scans with thin sections, reconstructed at ≤2 cm intervals.
Reconstructed slice collimation ≤2 mm.
High resolution reconstruction algorithm.
Field of view to include lungs only.
Expiratory scans are helpful to exclude lobular air trapping suggestive of hypersensitivity pneumonitis.
Prone scans if dependent density obscures detail on supine images.
Optional coronal and sagittal reconstructions if volumetric images are obtained.

ATS = American Thoracic Society; ERS = European Respiratory Society; HRCT = high resolution computerised tomography; ILD = interstitial lung disease; IPF = idiopathic pulmonary fibrosis