Left innominate vein aneurysm: diagnostic imaging and pitfalls.

Thoracic venous aneurysms are very rare. They may be asymptomatic and can be found incidentally during imaging. They are associated with few complications including pulmonary embolism, rupture, and venous obstruction. Accurate diagnosis of a mediastinal aneurysm is essential to avoid complications secondary to biopsy or surgical intervention. This is a rare case of left innominate vein aneurysm, its imaging, as well as associated imaging shortfalls.

CT-guided biopsy of bone: a radiologist's perspective.

OBJECTIVE: We present an overview of approaches for bone biopsy used to minimize potential tumor seeding of adjacent soft-tissue structures and compartments. We discuss a variety of approaches related to specific anatomic parts and review pertinent anatomy. CONCLUSION: We provide important guidelines and key examples that will help readers perform percutaneous needle bone biopsy safely.

US diagnosis of UCL tears of the thumb and Stener lesions: technique, pattern-based approach, and differential diagnosis.

The thumb is a central component supporting the intricate movements of the hand. Patients with acute thumb pain, particularly after trauma, require prompt evaluation of structural integrity, thus avoiding long-term morbidity such as instability, chronic pain, and osteoarthritis. Injury to the ulnar collateral ligament (UCL) of the thumb requires imaging for diagnosis of surgically important entities such as the Stener lesion. Historically, routine radiography including stress views does not allow such diagnosis and is potentially detrimental to patient care. Both magnetic resonance imaging and ultrasonography (US) are currently used for direct evaluation of the UCL of the thumb and are safe and accurate. US is more dynamic and less time-consuming and may be easier to perform. Furthermore, other disorders such as tenosynovitis, tendon tears, and articular pathologic conditions can involve the thumb and thenar region and may also be diagnosed with US. In this context, US is an underused tool because it is potentially an adjunct to the clinical examination in the appropriate setting. A sound knowledge of the regional anatomy and basic training in the principles of US should equip the imager with the skills necessary to evaluate the UCL of the thumb and its surrounding structures.

Sonographic characteristics of peripheral nerve sheath tumors.

OBJECTIVE: We have found variability in the sonographic appearance of peripheral nerve sheath tumors. The purpose of this study was to characterize the sonographic appearances of pathologically proven peripheral nerve sheath tumors. CONCLUSION: Peripheral nerve sheath tumors are often hypoechoic with posterior acoustic enhancement and so may simulate a ganglion cyst. The presence of intrinsic blood flow on color Doppler sonography and peripheral nerve continuity suggests the diagnosis of peripheral nerve sheath tumor. Sonography cannot reliably distinguish neurofibromas from schwannomas.