A Resident Perspective on Adding Value as Radiologists.

During the annual 46th annual American Alliance of Academic Chief Residents in Radiology (A(3)CR(2)) meeting in New Orleans, chief residents discussed the role of residents within American College of Radiology 3.0 campaign. Our discussion was directed toward the evolving role of fourth-year radiology residents and how we might improve their training to better prepare them to add value as both leaders and radiologists. The ideas resulting from our Problem Solving session were divided into three categories: clinical presence in the wards and subspecialty clinics; visibility to clinicians and patients; and the education of medical students, residents, and advanced practice clinicians to aid in realizing the long-term goals of Imaging 3.0.

MR Imaging of the Lumbosacral Plexus: A Review of Techniques and Pathologies.

The lumbosacral plexus is a complex anatomic area that serves as the conduit of innervation and sensory information to and from the lower extremities. It is formed by the ventral rami of the lumbar and sacral spine which then combine into larger nerves serving the pelvis and lower extremities. It can be a source of severe disability and morbidity for patients when afflicted with pathology. Patients may experience motor weakness, sensory loss, and/or debilitating pain. Primary neurologic processes can affect the lumbosacral plexus in both genetic and acquired conditions and typically affect the plexus and nerves symmetrically. Additionally, its unique relationship to the pelvic musculature and viscera render it vulnerable to trauma, infection, and malignancy. Such conditions are typically proceeded by a known history of trauma or established pelvic malignancy or infection. Magnetic resonance imaging is an invaluable tool for evaluation of the lumbosacral plexus due to its anatomic detail and sensitivity to pathologic changes. It can identify the cause for disability, indicate prognosis for improvement, and be a tool for delivery of interventions. Knowledge of proper MR protocols and imaging features is key for appropriate and timely diagnosis. Here we discuss the relevant anatomy of the lumbosacral plexus, appropriate imaging techniques for its evaluation, and discuss the variety of pathologies that may afflict it.

Sonographic appearance of adnexal torsion, correlation with other imaging modalities, and clinical history.

This pictorial essay illustrates the varied imaging appearances of adnexal torsion and its diagnostic pitfalls. This is a difficult diagnosis with many false positives and false negatives. Diagnosis is mostly based on clinical history and ultrasound examination, with computed tomography and/or magnetic resonance used to support the diagnosis and to exclude other pathologies.

Surface phase behavior and microstructure of lipid/PEG-emulsifier monolayer-coated microbubbles.

Langmuir trough methods and fluorescence microscopy were combined to investigate the phase behavior and microstructure of monolayer shells coating micron-scale bubbles (microbubbles) typically used in biomedical applications. The monolayer shell consisted of a homologous series of saturated acyl chain phospholipids and an emulsifier containing a single hydrophobic stearate chain and polyethylene glycol (PEG) head group. PEG-emulsifier was fully miscible with expanded phase lipids and phase separated from condensed phase lipids. Phase coexistence was observed in the form of dark condensed phase lipid domains surrounded by a sea of bright, emulsifier-rich expanded phase. A rich assortment of condensed phase area fractions and domain morphologies, including networks and other novel structures, were observed in each batch of microbubbles. Network domains were reproduced in Langmuir monolayers under conditions of heating-cooling followed by compression-expansion, as well as in microbubble shells that underwent surface flow with slight compression. Domain size decreased with increased cooling rate through the phase transition temperature, and domain branching increased with lipid acyl chain length at high cooling rates. Squeeze-out of the emulsifier at a surface pressure near 35 mN/m was indicated by a plateau in Langmuir isotherms and directly visualized with fluorescence microscopy, although collapse of the solid lipid domains occurred at much higher surface pressures. Compression of the monolayer past the PEG-emulsifier squeeze-out surface pressure resulted in a dark shell composed entirely of lipid. Under certain conditions, the PEG-emulsifier was reincorporated upon subsequent expansion. Factors that affect shell formation and evolution, as well as implications for the rational design of microbubbles in medical applications, are discussed.