AJR: CTA identifies alternative diagnoses beyond negative PE
CT angiography (CTA) can identify abnormalities and injury beyond the pulmonary arteries, including broken bones and heart disease in pediatric patients, according to a study published in the September issue of the American Journal of Roentgenology.

Children with clinically suspected pulmonary embolism are increasingly being evaluated with CTA, according to the authors. Even though many children ultimately test negative for pulmonary embolism, previous study results suggest that CTA is still valuable for this indication because it has the capability to accurately detect a variety of alternative diagnoses.

Edward Y. Lee, MD, from the departments of radiology and medicine, pulmonary division at Children's Hospital Boston and Harvard Medical School in Boston, and colleagues included 89 CTA exams with clinically suspected pulmonary embolism.

Researchers found that 41 percent of those CTA exams were normal and 15.5 percent of the children were found to have pulmonary embolism on CTA. However, they found that CTA provided them with an alternative diagnosis to pulmonary embolism in 59 percent of the exams performed.

Of the 15.5 percent, the authors noted that pulmonary embolism was localized in the lobar pulmonary artery in 39 percent, the segmental pulmonary artery in 35 percent, the subsegmental pulmonary artery in 16 percent and the main or central pulmonary artery in 10 percent.

“The two most common alternative diagnoses were pneumonia and atelectasis,” said Lee. “However, a variety of other alternative diagnoses, including congenital heart disease, pulmonary hypertension, rib fractures, and more, were identified throughout the thorax.

“One of the most important advantages of CTA is its ability to show alternative diagnoses in pediatric and adult patients without evidence of pulmonary embolism,” Lee said. “Our findings emphasize the importance of systemically searching beyond the pulmonary arteries for an alternative diagnosis when interpreting pulmonary CTA studies in children.”