CT Diagnostic Criteria For UIP
CT Diagnostic Criteria For UIP
CT Diagnostic criteria for UIP
Thoracic high resolution CT scan is the first line test for diagnosing ILD and idiopathic pulmonary fibrosis (IPF).
In about 50% of cases, the thoracic HRCT shows a characteristic usual interstitial pneumonia (UIP) pattern, supporting the IPF diagnosis without performing lung biopsy in an appropriate clinical context.
For a CT to suggest UIP, a certain number of CT criteria must be met according to an official ATS/ERS/JRS/ALAT clinical pratice guideline.
Subpleural and basal
- Distribution is often heterogeneous
Variants of distribution: occasionally diffuse, may be asymmetrical
Honeycombing
- With or without traction bronchiectasis or bronchiolectasis
Possibly superimposed mild ground-glass opacities, reticular pattern, pulmonary ossification
Subpleural and basal predominance of anomalies
- Distribution is often heterogeneous
Reticular pattern with peripheral
- traction bronchiectasis or bronchiolectasis
May have mild ground-glass opacities
Subpleural and basal predominant
- Subtle reticulation
may have mild ground-glass opacities or distortion
(“early UIP pattern”)
CT features and/or distribution of lung fibrosis that do not suggest any specific etiology (“truly indeterminate”)
Predominant distribution
- Peribronchovascular
- Perilymphatic
- Upper or mid-lung
CT features:
- Cysts
- Marked mosaic attenuation
- Predominant GGO
- Profuse micronodules
- Centrilobular nodules
- Nodules
- Consolidation
Orientation to a secondary pulmonary fibrosis
- Pleural plaques (asbestosis)
- Dilated esophagus (CTD)
- Distal clavicular erosions (RA)
- Extensive lymph node enlargement
- Pleural effusions, pleural thickening (CTD/drugs)