Pulmonary opacification represents the result of a decrease in the ratio of gas to soft tissue (blood, lung parenchyma and stroma) in the lung. When reviewing an area of increased attenuation (opacification) on a chest radiograph or CT it is vital to determine where the opacification is. The patterns can broadly be divided into airspace opacification, lines and dots.
Classification of pulmonary opacification
- airspace opacification
- linear opacification
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nodular opacification
- miliary (<2 mm), e.g. miliary tuberculosis
- micronodular (2-7 mm), e.g. acute hypersensitivity pneumonitis
- nodule (7-30 mm), e.g. lung metastasis, lung granuloma
- mass (>30 mm), e.g. bronchogenic carcinoma
- pulmonary mucoid impaction, e.g. ABPA
See also
-
parenchymal lung disease
- pulmonary opacification
- pulmonary lucency