Long Jiang Zhang MD, Abstract Co-Author: Nothing to Disclose

Guang Ming Lu MD, PhD, Abstract Co-Author: Nothing to Disclose

Jiuhong Chen MD, PhD, Presenter: Employee, Siemens AG

The purpose of this study was to evaluate the incidence and anatomical distribution of pulmonary embolism (PE) and renal vein thrombosis (RVT) in pediatric patients with nephritic syndrome using combined dual energy CT pulmonary angiography (DE-CTPA) and renal CT venography (rCTV), and to evaluate whether DE-CTPA can improve the detection of PE in these children.

Thirty two children (age ≤ 18 years) were included in this study. All children underwent contrast enhanced DE-CTPA and rCTV, 7 of them also had follow up DECT studies. The presence of PE was determined by 1) CTPA derived from the average weighted 120 kVp images; 2) DE-CTPA using dedicated dual energy software, Lung PBV and Lung Vessels applications, which can extract the iodine contents in lung parenchyma and pulmonary artery (PA). The incidence and the anatomical distribution of PE at the CTPA from the average weighted 120 kVp images, DE-CTPA, and of RVT at rCTV were recorded by two radiologists in consensus; Chi-square test was used to compare the difference of detection rate of PE with DE-CTPA and the conventional CTPA. Follow-up CT studies were also investigated if they were available.

Of 32 children, 9 patients (28.1%) had PE based on the comprehensive DE-CTPA evaluation. PE was localized in the lobar PA in 5 (55.6%), segmental PA in 6 (66.7%), the subsegmental PA in 5 (55.6%) patients. Compared with conventional CTPA, comprehensive DE-CTPA showed solitary subsegmental PE in one additional patient (9 patients vs. 8 patients), one additional segmental (11 segments vs. 10 segments), and four additional subsegmental PE (2 vs. 6 subsegmental PE) (all P＞0.05). Eight children (25%, 8/32) had RVT extending to inferior vena cava (n=5). Of 7 patients who also received follow-up DE-CTPA and rCTV studies, 4 patients showed resolution of both the PE and RVT, one patient showed persistent PE and RVT, one patient had only residual clots in segmental PA, and another patient showed no PE or RVT at the initial and follow-up DECT studies.

The prevalence of PE is 28.1% and RVT 25.0% in the nephritic children based on our small cohort. All nephritic children with RVT have PE with a predilection for segmental and subsegmental PAs. DE-CTPA has a potential to improve the detection of PE in pediatric population.

DE-CTPA has a potential to improve the detection of PE in pediatric population.

Zhang, L, Lu, G, Chen, J, Evaluation of Pulmonary Embolism in Pediatric Patients with Nephritic Syndrome with Dual-Energy CT Pulmonary Angiography.  Radiological Society of North America 2011 Scientific Assembly and Annual Meeting, November 26 - December 2, 2011 ,Chicago IL. http://archive.rsna.org/2011/11005192.html