Vascular Anomalies of the Pediatric Liver.

The liver is a unique organ as it receives afferent blood supply from the umbilical vein, portal vein, and hepatic artery in the developing embryo but has only one efferent drainage method, through the hepatic veins. In the postnatal period, about 70% of the afferent blood flow into the liver is from the portal venous system, unique vessels that begin and end in a capillary system. Vascular anomalies of the hepatic artery, hepatic veins, portal vein, and/or umbilical vein can be congenital or acquired secondary to inflammation and/or infection, trauma, systemic disorders, or iatrogenic causes. The vascular anomalies can be incidental findings at imaging, or the infant or child can present with symptoms such as abdominal pain and ascites, be diagnosed with gastrointestinal bleeding, and have abnormal liver function test results. Imaging can demonstrate vascular findings such as shunts, thrombosis, or collaterals; secondary parenchymal findings such as diffuse or focal abnormal enhancement patterns; and parenchymal lesions such as regenerative nodules. This article discusses and illustrates vascular disorders of the liver that may be encountered in the pediatric population. These include (a) normal vascular variants; (b) congenital anomalies (preduodenal portal vein and infradiaphragmatic total anomalous pulmonary venous return); (c) acquired thromboses (extrahepatic portal venous thrombosis); (d) inflammatory vascular conditions, which can result in hepatic artery aneurysms or pseudoaneurysms; (e) hepatic venous outflow disorders (veno-occlusive disease); and shunt lesions. Liver transplantation and associated vascular complications are a large topic and will not be reviewed in this article. Knowledge of the vascular and parenchymal changes seen with these entities can aid imaging diagnosis and guide appropriate management. ©RSNA, 2019.

Sarcoidosis: radiographic manifestations in the nails and distal phalanges.

Sarcoidosis is a granulomatous disease which can affect multiple organ systems. Clinical and radiologic manifestations depend on the organ system involved and the chronicity of disease. Nail involvement in sarcoidosis is rare, but is clinically relevant as it indicates chronic systemic disease. Nail abnormalities can be identified radiographically, and when seen in patients with known or suspected sarcoidosis, should prompt careful evaluation of the underlying bone for osseous involvement. We describe a case of sarcoidosis with radiographic findings in the nails and distal phalangeal tufts, which were indicative of nail and osseous sarcoid involvement and strongly supported the presence of chronic systemic disease. Although the nail findings resolved clinically and on radiographs after treatment, the osseous findings showed only minimal improvement. To our knowledge, the radiographic findings of nail sarcoidosis have not been previously addressed in the literature.

Utility of Gadolinium Use in the Imaging Follow-Up of Nonenhancing Primary Brain Neoplasms in Children.

Background and purpose Gadolinium-based contrast agents (GBCAs) have been administered clinically since 1988. They are remarkably well tolerated by children and result in dose-dependent tissue deposition, even in patients with normal renal function. No adverse effects of gadolinium deposition in patients with normal renal function have been established. Given the uncertain effects of gadolinium deposition, we sought to analyze gadolinium use in the imaging follow-up of nonenhancing primary brain neoplasms in children. Materials and methods This retrospective, institutional review board-approved and Health Insurance Portability and Accountability Act-compliant study evaluated pediatric patients who received GBCA in the routine evaluation of brain neoplasms. This special subset included 30 patients (<18 years old) with initially nonenhancing primary intracranial neoplasms who received treatment and follow-up at our institution. Patient data included sex, age from diagnosis to most recent imaging follow-up, number of contrast-enhanced magnetic resonance imaging (MRI) follow-up exams, and histopathology from a biopsy or resection. Results The group had an expected variety of tumors, including low-grade astrocytomas, dysembryoplastic neuroepithelial tumors, oligodendrogliomas, and teratomas. Half of our patients had tumors of unknown histopathology that were not biopsied or resected. The median age at diagnosis was 8.9 years, the median of four follow-up MRIs per patient, and the median follow-up time of four years. Only one of the 30 patients developed an enhancing focus on follow-up MRI that remained stable and asymptomatic over two years and did not require surgical intervention. Conclusion Judicious use of GBCA in children, especially when numerous exams over many years are anticipated, is advised given the data regarding soft-tissue deposition. Preliminary results suggest that it may be feasible to omit GBCA from routine follow-ups of initially nonenhancing brain neoplasms.

A 13-Year-Old Male Patient With Severe Multifocal Pneumonia and Bronchiectasis That Required Extracorporeal Membrane Oxygenation.

CASE PRESENTATION: A 13-year-old male patient with intermittent asthma and joint hypermobility presented to the ED in acute hypoxemic respiratory distress. He reported experiencing cough, increased work of breathing, and worsening chest pain for 3 days before presentation. He also reported fatigue and decreased appetite for 2 weeks. He had no known fever, myalgias, or recent weight loss. His medical history included two hospitalizations during early childhood for viral respiratory illnesses, one of which required intubation at 8 months of age. He had a gastrostomy tube placed shortly after his hospitalization because of failure to thrive secondary to aspiration based on a swallow study. His weight gain and growth improved with adequate nutrition, and his gastrostomy tube was removed at 2 years of age. His newborn screen, which included immunoreactive trypsinogen, was normal. He was noted to have hypermobile joints on physical examination at a clinic visit in childhood, but his examination results were not concerning for a hypermobility syndrome, and further diagnosis was not pursued. His parents endorsed that he has been a "healthy child" overall other than the occasional cough, which was attributed to asthma. His lifestyle was described as sedentary; he did not play any sports or have any unusual hobbies. He did not take any daily medications and no environmental exposures were reported. There was no family history of pulmonary, autoimmune, or connective tissue disease.

Acquired Whole-lung Mismatched Perfusion Defects on Pulmonary Ventilation/Perfusion Scintigraphy.

Despite the increasing use of computed tomography pulmonary angiography to evaluate for pulmonary embolism (PE), ventilation/perfusion (V/Q) scintigraphy is still a fairly common examination. A rare finding on V/Q scintigraphy is whole-lung mismatched perfusion defect. Although this finding can occur with PE, it has an important, limited differential diagnosis. In this pictorial essay, we describe different causes of acquired whole-lung mismatched perfusion defect.