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In this study, we proposed a method for detecting microcalcifications and tumor tissue using a cadmium telluride (CdTe) series linear
detector. The CdTe series detector was used as an energy resolved photon-counting (hereafter referred to as the photon-counting)
mammography detector. The CdTe series linear detector and two types of phantom were designed using a MATLAB simulation. Each
phantom consisted of mammary gland and adipose tissue. One phantom contained microcalcifications and the other contained tumor
tissue. We varied the size of these structures and the mammary gland composition. We divided the spectrum of an x-ray, which is
transmitted to each phantom, into three energy bins and calculated the corresponding linear attenuation coefficients from the numbers
of input and output photons. Subsequently, the absorption vector length that expresses the amount of absorption was calculated. When
the material composition was different between objects, for example mammary gland and microcalcifications, the absorption vector
length was also different. We compared each absorption vector length and tried to detect the microcalcifications and tumor tissue.
However, as the size of microcalcifications and tumor tissue decreased and/or the mammary gland content rate increased, there was
difficulty in distinguishing them. The microcalcifications and tumor tissue despite the reduction in size or increase in mammary gland
content rate can be distinguished by increasing the x-ray dosage. Therefore, it is necessary to find a condition under which a low
exposure dose is optimally balanced with high detection sensitivity. It is a new method to indicate the image using photon counting
technology.
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