Dianna M. E. Bardo

The “circle sign”: a new sonographic sign of pneumatosis intestinalis – clinical, pathologic and experimental findings

Background. Pneumatosis intestinals (PI) represents gas in the bowel wall. The appearance of PI using high-resolution ultrasound (HRUS) has not been well described. Objective. The purpose of this report is to describe a new ultrasound sign of pneumatosis seen in three patients. This sign, called the “circle sign”, is indicative of bubbles of gas within the circumference of the bowel, producing an appearance of a continuous echogenic ring on ultrasound. Further studies of the sonographic characteristics of pneumatosis were performed with an in vitro model. Materials and methods. HRUS was performed prospectively in three patients demonstrating extensive PI radiographically. The appearance of the gas was characterized and the behavior of the intramural bubbles was studied when the bowel was compressed with the ultrasound transducer. Either CT scan or pathologic correlation was obtained in all patients. Experimental models of PI using air injected into the wall of sausage casing were developed. Results. The presence of echogenic gas bubbles within the circumference of the wall of the bowel seen with HRUS was shown to represent pneumatosis intestinalis at histologic examination or by CT scanning in the three study patients. In vitro studies confirmed the clinical impression that the use of compression is helpful in distinguishing intramural from intraluminal air. Conclusion. The presence of echogenic gas bubbles in the wall of the bowel, often seen as a circle within the circumference of the bowel, may be helpful in diagnosing PI on ultrasound using HRUS.

Desmoplastic infantile ganglioglioma (DIG): cranial ultrasound findings.

Abstract Desmoplastic infantile ganglioglioma (DIG) is a rare brain tumor encountered in infants. In spite of its large size at presentation and occasional high mitotic activity on histopathology, the tumor has a good prognosis. A 7-month-old baby girl developed increasing head circumference. On ultrasound, a large multicystic mass was seen. We report the cranial ultrasound findings for the first time. Correlative imaging of this recently recognized entity is shown.

Superficial venous thrombosis presenting as a painful popliteal fossa mass in a child

We report an unusual case of superficial venous thrombosis in a cyanotic 12‐year‐old child who had undergone recent appendectomy. Although compression, color Doppler, and duplex ultrasound techniques remain the keys to the diagnosis of venous thrombosis, SieScape sonography was beneficial in demonstrating the extent of the thrombi and their location along a superficial thrombosed vein.

Long-Term Outcomes of the Arterial Switch Operation for D-Transposition of the Great Arteries

Dextrotransposition of the great arteries (d-TGA) is a relatively rare form of complex childhood congenital heart disease, which occurs in approximately 0.2 in 1000 live births (Long et al, 2010). The most common palliative procedure for this anatomy has become the arterial switch operation (ASO). We will review in this paper the evidence that is currently available regarding the clinical management following the ASO. Individuals with d-TGA who undergo ASO at a young age thus far have excellent long-term outcomes. Long-term complications for the ASO should be monitored for and patients should have routine follow-up with specialists in adult congenital heart disease.

Magnetic resonance imaging of the pediatric mediastinum

The mediastinum, the central anatomical space of the thorax, is divided by anatomical landmarks but not by physical boundaries. The mediastinum is a conduit, a space through which cranial nerves, important nerve branches, the sympathetic chain, vascular structures, and visceral structures, the trachea and esophagus pass. This arrangement allows contiguous extension or communication of disease along facial planes and through potential spaces to and from the head and neck or cervical spine, to and from the superior mediastinum, between superior and inferior mediastinal levels, and between inferior mediastinal spaces into the intra- and retroperitoneal spaces. Magnetic resonance imaging (MRI) of the mediastinum in children poses technical challenges, in particular cardiac and respiratory motion, and diagnostic challenges, including a broad range of tissue types and possible diagnoses. In this paper we review mediastinal anatomy, MRI sequences and protocol choices and include a short discussion of features and MRI findings of some of the congenital and acquired pathologies that are most often encountered in the pediatric mediastinum.

Pediatric Cardiac CTA

Multi-detector computed tomography (MDCT) is ideally suited for imaging anatomic and functional cardiac abnormalities in congenital heart disease (CHD) when using ECG-triggering (prospective) or ECG-gating (retrospective) scan techniques with at least 64 detector rows. The newest MDCT scanners employ up to five times greater number of detector rows, improved temporal resolution, multi-energy spectral data, and iterative image reconstruction techniques. Wide detector arrays allow volumetric scanning of the entire heart in a single gantry rotation. Improved temporal resolution with faster gantry rotation and dual detector arrays is especially important when imaging the heart in infants and young children who have heart rates typically up to 140 beats per min or greater and cannot follow instructions for breath holding and remaining motionless. Spectral multi-energy CT allows reconstruction of image data using standard Hounsfield units or at two or more energy levels which may enable determination of myocardial perfusion, differentiate tissue composition, and using low monoEnergy settings boost conspicuity of intravascular contrast in poorly timed or low contrast volume examinations. Iterative reconstruction improves image quality by reducing noise, elevating the signal to noise in the image, and thereby allowing the user to reduce mA or kV. Each of these innovations in MDCT technology empowers the user to markedly reduce radiation dose while maintaining or improving image quality.

Optimizing Cardiac CTA Acquisition in Congenital Heart Disease

Purpose of ReviewThe purpose of this review of performance of cardiac computed tomographic angiography (CCTA) in patients with congenital heart disease (CHD) is to describe a strategy for optimizing CCTA protocols for various forms of CHD at diagnosis and throughout the lifetime of a patient.Recent FindingsRecent expert consensus statements provide key recommendations for patient selection and technical performance of CCTA with tips to optimize contrast injection, scan acquisition, and understanding anatomy and postoperative changes in patients with CHD. Spectral CT will become invaluable in acquiring image data which has potential for enabling improved image quality and perhaps physiologic information.Summary CCTA is an important non-invasive imaging modality for making initial diagnosis and providing follow-up imaging in patients of all ages with CHD. Optimization of imaging protocols requires combined expertise in all forms of CHD, surgical palliation procedures, and knowledge of surgical options for CHD surgery.