Assessment of superior mesenteric vascular flow quantitation in children using four-dimensional flow magnetic resonance imaging: A feasibility study

BACKGROUND Four-dimensional (4D) flow magnetic resonance imaging (MRI) is used as a noninvasive modality for assessing hemodynamic information with neurovascular and body applications. The application of 4D flow MRI for assessment of bowel disease in children has not been previously described. AIM To determine feasibility of superior mesenteric venous and arterial flow quantitation in pediatric patients using 4D flow MRI. METHODS Nine pediatric patients (7-14 years old, 5 male and 4 female) with history or suspicion of bowel pathology, who underwent magnetic resonance (MR) enterography with 4D flow MR protocol from November 2022 to October 2023. Field strength/sequence: 3T MRI using 4D flow MR protocol. Flow velocity and peak speed measurements were performed by two diagnostic radiologists placing the region of interest in perpendicular plane to blood flow on each cross section of superior mesenteric artery (SMA) and superior mesenteric vein (SMV) at three predetermined levels. Bland-Altman analysis, showed good agreement of flow velocity and peak speed measurements of SMV and SMA between two readers. RESULTS Mean SMV flow velocity increased from proximal to mid to distal (0.14 L/minute, 0.17 L/minute, 0.22 L/minute respectively). Mean SMA flow velocity decreased from proximal to mid to distal (0.35 L/minute, 0.27 L/minute, 0.21 L/minute respectively). Observed agreement was good for flow velocity measurements of SMV (mean bias -0.01 L/minute and 95% limits of agreement, -0.09 to 0.08 L/minute) and SMA (mean bias -0.03 L/minute and 95% limits of agreement, -0.23 to 0.17 L/minute) between two readers. Good agreement for peak speed measurements of SMV (mean bias -1.2 cm/second and 95% limits of agreement, -9.4 to 7.0 cm/second) and SMA (mean bias -3.2 cm/second and 95% limits of agreement, -31.4 to 24.9 cm/second). CONCLUSION Flow quantitation using 4D Flow is feasible to provide hemodynamic information for SMV and SMA in children.