Purpose or Case Report: Abdominal Magnetic Resonance Angiography (MRA) has gained favor in pediatric patients due to its lack of ionizing radiation and noninvasive nature. Reports exist regarding incidental findings on body MRA in adult patients. However, the incidental findings in pediatric abdominal MRA have not been previously reported. Our study aims to determine the frequencies, characteristics and categories of incidental findings in pediatric patients undergoing abdominal MRA.
Methods & Materials: Retrospective study was performed in 78 consecutive contrast-enhanced abdominal MRA of patients between age 0-20 years over a 7 year time-period. The presence of incidental vascular and extravascular findings was noted. Reports were categorized in consensus by 2 radiologists as no incidental finding (group A), normal/normal variants/non-significant incidental common findings (group B), or abnormal incidental findings (group C). Group C was reviewed to determine whether or not additional management was performed.
Results: 40 boys and 38 girls (51%:49%) were reported with mean age 12.3 yrs (SD±5.6 yrs, range 7 d-20 yrs). Three most common indications for MRA were renal artery stenosis (24.4%), vasculitis (21.8%), and suspected intra-abdominal venous thrombosis (14.1%). We identified a total of 92 incidental findings in 50/78 patients; 60 findings in 28 patients in group B and 32 findings in 21 patients in group C (see Table). Atelectasis at the lung bases was the most common incidental group B finding (14/78 patients). The most common findings in group C were ascites, scoliosis, and splenomegaly. There were 3 abnormal incidental findings that lead to causative workup and/or further management (moderate ascites, pericardial/pleural effusion, and venous malformation). The remaining cases with abnormal findings received treatment of their primary conditions only.
Conclusions: Pediatric abdominal MRA revealed a large number of incidental findings. The large majority were findings without clinical significance. Basal lung atelectasis was the most common overall incidental and non-significant findings, while ascites was the most common abnormal incidental findings. Although not all abnormal incidental findings affected management, appropriate identification and communication of relevant findings would improve patient care.