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Purpose: Multiple-image radiography (MIR) is an analyzer-based synchrotron X-ray imaging approach capable of dissociating absorption, refraction, and scattering components of X-ray interaction with the material. It generates additional image contrast mechanisms (besides absorption), especially in the case of soft tissues, while minimizing absorbed radiation dose. Our goal is to develop a contrast agent for MIR using ultrasound microbubbles by carrying out a systematic assessment of size, shell material, and concentration. Procedures: Microbubbles were synthesized with two different shell materials: phospholipid and polyvinyl-alcohol. Polydisperse perfluorobutane-filled lipid microbubbles were divided into five size groups using centrifugation. Two distributions of air-filled polymer microbubbles were generated: 2–3 µm and 3–4 µm. A subset of polymer microbubbles 3–4 µm had iron oxide nanoparticles incorporated into their shell or coated on their surface. Microbubbles were immobilized in agar with different concentrations: 5 × 107, 5 × 106, and 5 × 105 MBs/ml. MIR was conducted on the BioMedical Imaging and Therapy beamline at the Canadian Light Source. Three images were generated: Gaussian amplitude, refraction, and ultra-small-angle X-ray scattering (USAXS). The contrast signal was quantified by measuring mean pixel values and comparing them with agar. Results: No difference was detected in absorption or refraction images of all tested microbubbles. Using USAXS, a significant signal increase was observed with lipid microbubbles 6–10 µm at the highest concentration (p = 0.02), but no signal was observed at lower concentrations. Conclusions: These data indicate that lipid microbubbles 6–10 µm are candidates as contrast agents for MIR, specifically for USAXS. A minimum concentration of 5 × 107 microbubbles (lipid-shell 6–10 µm) per milliliter was needed to generate a detectable signal. [ABSTRACT FROM AUTHOR]

We report an unusual case of chronic mesenteric ischemia presenting in a 12-year-old girl with idiopathic infantile arterial calcinosis (IIAC). This is the first reported case in the literature of chronic mesenteric ischemia in the setting of IIAC. The girl presented with a classical history of postprandial abdominal pain. Imaging demonstrated significant stenoses of the celiac axis, superior mesenteric artery (SMA) and inferior mesenteric artery (IMA). Angioplasty of the celiac axis and SMA was attempted, with successful dilation of the SMA only. At 3-, 6- and 12-month follow-ups, the child's symptoms had almost resolved. This case report has three important ramifications: chronic mesenteric ischemia is a possible clinical presentation in children with IACC, pre-angioplasty imaging is important in guiding treatment approach, and angioplasty was effective in this case of chronic mesenteric ischemia and offers hope for other similarly affected children. [ABSTRACT FROM AUTHOR]

Survivors of childhood Wilms tumors are at an increased risk of second malignant neoplasms. Recently, it has been postulated that renal cell carcinoma is among the malignancies for which this population is at risk. We present the unique case of an adult Wilms tumor survivor with non-syndromic hemihypertrophy (NSHH) who developed renal cell carcinoma. This case highlights the need for close follow-up in two populations: adults who have survived Wilms tumor and those with NSHH. [ABSTRACT FROM AUTHOR]

Physiologic changes in renal transplant patients, such as transiently low central venous pressure, may be related to increased intra-abdominal pressure, from the volume of the transplanted kidney itself. Using intraoperative and postoperative Doppler ultrasound of the transplant renal vessels, we identified changes in flow dynamics following closure of the abdomen and reversal of the changes when the abdomen was reopened. This was attributed to abdominal compartment syndrome and a fasciotomy was created in the abdominal wall to accommodate the transplanted kidney. The findings in this case, in keeping with abdominal compartment syndrome, are not often considered in transplant recipients, but may explain some of the postsurgical physiology in some patients, particularly in the pediatric population. [ABSTRACT FROM AUTHOR]

Bronchial varices, which have rarely been described in the radiology literature, can be the result of pulmonary venous obstruction and may present with hemoptysis. This case is an illustration of this rare condition, which correlates CT findings with bronchoscopic findings. We also describe the findings on phase-contrast MR that demonstrated reversed diastolic flow in the branch pulmonary artery supplying the affected lung. [ABSTRACT FROM AUTHOR]