Optimized high-resolution contrast-enhanced hepatobiliary imaging at 3 tesla: a cross-over comparison of gadobenate dimeglumine and gadoxetic acid.

PURPOSE: To evaluate the signal to noise ratio (SNR) and contrast to noise ratio (CNR) performance of 0.05 mmol/kg gadoxetic acid and 0.1 mmol/kg gadobenate dimeglumine for dynamic and hepatobiliary phase imaging. In addition, flip angles (FA) that maximize relative contrast-to-noise performance for hepatobiliary phase imaging were determined. MATERIALS AND METHODS: A cross-over study in 10 volunteers was performed using each agent. Imaging was performed at 3 Tesla (T) with a 32-channel phased-array coil using breathheld 3D spoiled gradient echo sequences for SNR and CNR analysis, and for FA optimization of hepatobiliary phase imaging. RESULTS: Gadobenate dimeglumine (0.1 mmol/kg) had superior SNR performance during the dynamic phase, statistically significant for portal vein and hepatic vein in the portal venous and venous phase (for all, P < 0.05) despite twice the approved dose of gadoxetic acid (0.05 mmol/kg), while gadoxetic acid had superior SNR performance during the hepatobiliary phase. Optimal FAs for hepatobiliary phase imaging using gadoxetic acid and gadobenate dimeglumine were 25-30° and 20-30° for relative contrast liver versus muscle (surrogate for nonhepatocellular tissues), and 45° and 20° (relative contrast liver versus biliary structures), respectively. CONCLUSION: Gadobenate dimeglumine may be preferable for applications that require dynamic phase imaging only, while gadoxetic acid may be preferable when the hepatobiliary phase is clinically important. Hepatobiliary phase imaging with both agents benefits from flip angle optimization.

Percutaneous treatment of insufficiency fractures : principles, technique and review of literature.

Insufficiency fractures of the pelvis, sacrum, spine, and long bones are painful, debilitating, and are common consequences of osteoporosis. Conventional treatment for these fractures varies from conservative therapy to surgery with plate and screw fixation. The former fails to address the underlying problem of fracture and frequently does not alleviate symptoms, while the latter is invasive and not always possible in older populations with low bone density and numerous co-morbidities. Osseous augmentation with polymethylmethacrylate (PMMA) has been used for over two decades to treat fractures related to osteoporosis, but has not been commonly used to treat fractures outside of the vertebral bodies. Osseous augmentation with PMMA is an image-guided procedure and various techniques have been utilized to treat fracture in different locations. We describe various techniques for image-guided osseous augmentation and treatment of insufficiency fractures with bothPMMA and allograft bone for fractures of the pelvis including sacrum, acetabulum, pubic symphysis, pubic rami ilium; appendicular skeleton including distal radius, proximal femur, and vertebral body. We also describe the potential risks and complications associated with percutaneous treatment of insufficiency fractures and techniques to avoid the pitfalls of the various procedures. We will present the process for patient follow-up and data regarding the pre- and postprocedure pain response in patients undergoing treatment for pelvic insufficiency fractures.

Percutaneous augmentation of the superior pubic ramus with polymethyl methacrylate: treatment of acute traumatic and chronic insufficiency fractures.

The injection of polymethylmethacrylate (PMMA) is a minimally invasive image-guided procedure that is typically used to treat vertebral body fractures due to osteoporosis or neoplastic involvement. The injection of PMMA into various other locations including the sacrum, acetabulum, pedicles, femur and tibia has been reported previously, and these procedures have, overall, been highly effective at alleviating pain and discomfort. Although the injection of PMMA into the vertebral body is a very common procedure that has been performed for over 2 decades for the percutaneous treatment of vertebral body fractures, the percutaneous injection of PMMA has not been reported in the English literature as treatment for superior pubic ramus fractures. We report the percutaneous treatment of an acute superior pubic ramus fracture and of a chronic insufficiency fracture of the superior pubic ramus using a parasymphyseal approach to access the region of injury.

Oklahoma and the issue of tobacco.

Tobacco use, particularly cigarette smoking, continues to be the leading cause of preventable morbidity and mortality in the United States. An important public health issue, this has been the focus of much study. Several organizations have issued statements and recommendations for handling this issue. Reducing tobacco use is a key component of Healthy People 2010, the national action plan for improving the health of all Americans. The Surgeon General, Agency for Healthcare Research and Quality (AHRQ) and the U.S. Preventive Services Task Force (USPSTF) have put forth valuable guidelines concerning preventive services in the primary care setting, and programs such as Putting Prevention into Practice (PPIP) and state based initiatives have aimed to implement them. States that have taken these messages to heart and acted upon them to fully implement these preventive measures and interventions have had significant success, most notably Oregon, California and Massachusetts. In less than a decade, the Massachusetts Tobacco Control Program has evolved into one of the leading public health initiatives of our time. Perhaps by learning from their successes we can bring about a similar change in the state of Oklahoma.