Increasing the field of view in grating based X-ray phase contrast imaging using stitched gratings.

Grating based X-ray differential phase contrast imaging (DPCI) allows for high contrast imaging of materials with similar absorption characteristics. In the last years' publications, small animals or parts of the human body like breast, hand, joints or blood vessels have been studied. Larger objects could not be investigated due to the restricted field of view limited by the available grating area. In this paper, we report on a new stitching method to increase the grating area significantly: individual gratings are merged on a carrier substrate. Whereas the grating fabrication process is based on the LIGA technology (X-ray lithography and electroplating) different cutting and joining methods have been evaluated. First imaging results using a 2×2 stitched analyzer grating in a Talbot-Lau interferometer have been generated using a conventional polychromatic X-ray source. The image quality and analysis confirm the high potential of the stitching method to increase the field of view considerably.

Note: Gratings on low absorbing substrates for x-ray phase contrast imaging.

Grating based X-ray phase contrast imaging is on the verge of being applied in clinical settings. To achieve this goal, compact setups with high sensitivity and dose efficiency are necessary. Both can be increased by eliminating unwanted absorption in the beam path, which is mainly due to the grating substrates. Fabrication of gratings via deep X-ray lithography can address this issue by replacing the commonly used silicon substrate with materials with lower X-ray absorption that fulfill certain boundary conditions. Gratings were produced on both graphite and polymer substrates without compromising on structure quality. These gratings were tested in a three-grating setup with a source operated at 40 kVp and lead to an increase in the detector photon count rate of almost a factor of 4 compared to a set of gratings on silicon substrates. As the visibility was hardly affected, this corresponds to a significant increase in sensitivity and therefore dose efficiency.

Diabetes UK evidence-based nutrition guidelines for the prevention and management of diabetes.

This article summarizes the Diabetes UK evidence-based guidelines for the prevention of Type 2 diabetes and nutritional management of diabetes. It describes the development of the recommendations and highlights the key changes from previous guidelines. The nutrition guidelines include a series of recommendations for the prevention of Type 2 diabetes, nutritional management of Type 1 and Type 2 diabetes, weight management, management of microvascular and macrovascular disease, hypoglycaemia management, and additional considerations such as nutrition support, end-of-life care, disorders of the pancreas, care of the older person with diabetes, nutrition provided by external agencies and fasting. The evidence-based recommendations were graded using the Scottish Intercollegiate Guidelines Network methodology and, in a small number of topic areas, where strong evidence was lacking, the recommendations were reached by consensus. The Diabetes UK 2011 guidelines place an emphasis on carbohydrate management and a more flexible approach to weight loss, unlike previous guidelines which were expressed in terms of recommendations for individual nutrient intakes. Additionally, the guidelines for alcohol have been aligned to national recommendations. The full evidence-based nutrition guidelines for the prevention and management of diabetes are available from: http://www.diabetes.org.uk/nutrition-guidelines.

The diffusion of a medical innovation: where teleradiology is and where it is going.

Teleradiology is one of the more successful applications of telemedicine as measured by a bibliometric analysis of teleradiology research publications. The organizational diffusion of innovation framework is helpful in understanding the diffusion of teleradiology. Teleradiology had become part of the practices of two-thirds of radiologists who responded to the American College of Radiology survey in 1999. It is clear that teleradiology has become routinized even though quantitative data are hard to find. Telecardiology may be the next successfully diffused form of telemedicine. The potential cloud on the horizon for telediagnostics is political pressure to avoid outsourcing to foreign countries, particularly those to which US information technology jobs have already been transferred. How the outsourcing issue is resolved will have a significant effect on teleradiology specifically, and, perhaps, telemedicine generally.