Parenchymal and pleural abnormalities in children with and without pulmonary embolism at MDCT pulmonary angiography.

BACKGROUND: Prior studies in adults suggest that a wedge-shaped peripheral consolidation may be predictive of pulmonary embolism (PE). In contrast, a previous study in children provided no evidence of an association between this finding and PE, but it was limited by a small sample size and was not specifically designed to answer this question.

OBJECTIVE: To compare the frequencies of parenchymal and pleural abnormalities in children with and without PE at multidetector computed tomographic pulmonary angiography (CTPA).

MATERIALS AND METHODS: The study population included 22 consecutive pediatric patients (11 males, 11 females; mean age 13.2 +/- 5.8 years; range 4 months to 18 years) with PE diagnosed by CTPA from July 2004 to January 2009 and identified using our hospital database. The comparison group included 22 randomly selected pediatric patients (10 males, 12 females; mean age 15.2 +/- 3.3 years; range 5.6 to 18 years) who underwent CTPA studies without evidence of PE during the same study period. All CTPA studies were reviewed by consensus by two pediatric radiologists for the presence of parenchymal and pleural abnormalities including: wedge-shaped peripheral consolidation, other forms of consolidation, atelectasis, linear opacity, ground-glass opacity, mosaic attenuation pattern, nodule, mass, focal patchy increased attenuation, and pleural effusion. Differences in frequencies of parenchymal and pleural abnormalities between the two groups were analyzed by logistic regression to determine odds ratios for association with PE. The two groups were also compared with respect to risk factors for PE.

RESULTS: Wedge-shaped peripheral consolidation was seen in eight children (36%) with PE and in two children (9%) without PE [odds ratio = 5.7, 95% confidence interval (CI): 1.2 to 30, p = 0.03]. There were no significant differences in the frequency of other findings between the groups (all p-values > 0.10). Prior history of neoplasm was the only independent risk factor significantly associated with the presence of PE (p = 0.006).

CONCLUSION: Wedge-shaped peripheral consolidation is significantly associated with PE on CTPA studies of children. The identification of a wedge-shaped peripheral consolidation in children should alert radiologists to carefully evaluate for concurrent PE.