Exogenous lipoid pneumonia: serial chest plain roentgenography and high-resolution computerized tomography findings

Between May 1988 and July 2002, six patients with pneumonia due to diesel, animal, or vegetable oil aspiration were admitted to Kaohsiung Medical University Hospital. The purpose of this study was to demonstrate distinctive radiographic findings of oil-induced lipoid pneumonitis on initial serial chest roentgenograms and high-resolution computerized tomography (CT) scans. Initial chest roentgenograms (n = 6), CT scans (n = 6), and roentgenography and CT follow-up studies were analyzed retrospectively by two chest radiologists and two surgeons, focusing on the pattern and distribution of parenchymal abnormalities. The most common location was the right middle lobe, followed by the right lower lobe, the left lower lobe, and the lingular lobe. Follow-up chest roentgenograms (n = 6) showed complete disappearance of the parenchymal lesions in only one patient and partial decrease in the extent of lesions in five patients. Lipoid pneumonia presents non-specific findings on chest roentgenography. It is commonly located in both lower and the right middle lobes. On high-resolution CT, the lesions appear most commonly as areas of consolidation, ground-glass attenuation mixed with paving pattern, and poorly defined nodules.