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A quantitative theory for the contrast-to-noise ratio (CNR) in differential phase contrast imaging (DPCI) is proposed and compared to that of images derived from classical absorption contrast imaging (ACI). Most prominently, the CNR for DPCI contains the reciprocal of thespatial wavelength to be imaged, the fringe visibility, and a tunable factor dependent on the system geometry. DPCI is thus potentiallybeneficial especially for the imaging of small object structures. We demonstrate CNR calculations for mammography, finding optimal imaging energies between 15 and 22 keV for ACI, and between 20 and 40 keV for DPCI.

Philips has designed an optical mammography machine. In this machine the breast is suspended into a cup in which the measurements take place. A special fluid is inserted into the cup to prevent the light from going around the breast instead of going through it but this fluid also weakens the signal. Therefore the cup's shape should be close to the breast's shape. The aim of this project was to design a device to measure the breast's shape. This device was used to perform a pilot study among 18 women, 36 breasts in total. There are several possibilities to create 3D images for example MRI, interfero-metry and triangulation. The method of triangulation is chosen to build a set-up. This set-up contains a video projector to project images into a tank filled with water. Two camera's capture these images. Special software has been written in LabVIEW to create 3D images out of these data. The maximum height of the breast and the FWHM was measured for all breasts. A correlation was found between bra cup size and the maximum height of the breast. On average the breast was 64 mm high, with a standard deviation of 8.5 mm. No correlation was found between the FWHM and a form of bra size or chest circumference. The average FWHM is 7.6 cm with a standard deviation of 2.5 cm.

Differential phase-contrast imaging in the x-ray domain provides three physically complementary pieces of information: the attenuation,the differential phase-contrast, related to the refractive index, and the dark-field signal, related to the total amount of radiation scattered into very small angles. In medical applications, it is of the utmost importance to present to the radiologist all clinically relevant information in as compact a way as possible. Hence, the needarisis for a method to combine two or more of the above mentioned images into one image containing all information relevant for diagnosis. We present an image composition algorithm that fuses the attenuation image and the differential phase contrast image into a composite image. The composition is performed in a noise optimal way such that the composite image is characterized by minimal noise-power at each frequency component.