MDCT Pulmonary Angiography Evaluation of Pulmonary Embolism in Children

Abstract

The purpose of our study was to determine the prevalence and anatomic distribution of pulmonary embolism (PE) in a group of consecutive pediatric patients with clinically suspected PE using MDCT pulmonary angiography (pulmonary CTA). We used our hospital information system to retrospectively identify all consecutive pediatric patients (< 18 years of age) with clinically suspected PE who underwent pulmonary CTA from July 2004 to August 2007. Two experienced pediatric radiologists retrospectively reviewed by consensus a series of 98 consecutive pulmonary CTA studies. Each examination was reviewed for the ability to visualize pulmonary arteries and the presence of PE. For positive cases, the level of involvement was classified as central, lobar, segmental, or subsegmental. Lobar location was also recorded using standard nomenclature. Pulmonary CTA results were compared with the results of lower extremity ultrasound studies in the subset of patients who underwent both procedures. The study population consisted of 84 children who underwent a total of 98 pulmonary CTA studies. All pulmonary CTA studies were technically successful in visualizing arteries to the level of segmental pulmonary arteries, but the evaluation of subsegmental pulmonary arteries was limited in 78 (80%) examinations. Thirteen (15.5%) of 84 children were found to have PE on pulmonary CTA. PE was localized in the lobar pulmonary artery in 12 (39%), the segmental pulmonary artery in 11 (35%), the subsegmental pulmonary artery in five (16%), and the main or central pulmonary artery in three (10%) patients. PE was distributed in the right lower lobe in 12 (37%), the left lower lobe in eight (24%), the right upper lobe in five (15%), the right middle lobe in four (12%), and the left upper lobe in four (12%) patients. Ten of 13 patients with PE underwent lower extremity Doppler ultrasound, of whom one (10%) was positive for deep venous thrombosis. The prevalence of PE may be more common among pediatric patients than previously reported and has a similar distribution to that in adult patients.