AbstractID: 9743 Title: A novel digital mammography detector concept based on
Microchannel Plates
In an effort to improve image quality and reduce patient dose, a concept of a scanning multi-slit digital mammography
system with Microchannel Plate (MCP) detector is proposed. MCP detectors are known to have high spatial and temporal
resolution, direct conversion, high physical charge amplification, low noise, and pulse-counting capabilities. However, the
application of MCP detectors to X-ray imaging has been hampered by their low detection efficiency for photons in the
diagnostic energy range This problem was addressed using “edge-on” illumination mode for MCP1,2. A single slit
prototype of the “edge-on” MCP detector has recently been developed and tested. This scanning slit system produces
virtually noise and scatter free images in photon counting mode at 50 kVp. The proposed full-field mammography system
will be a stack of 20 single-slit “edge-on” MCP detectors. Each of the single slit detectors will utilize multi-channel
application specific integral circuit (ASIC) electronics to provide high-count rate and short scanning time. Basic design
parameters of the system are 20x20 cm2 full field, 100x100 µm2 pixel size, 6 s scanning time, <2% scatter fraction, >80%
photon detection efficiency, <2% dead time and <0.1photon/pixel noise equivalent signal. The total width of the slits will
be 4 mm. These parameters will provide a signal to noise ratio of 5 for 112 µm microcalcifications using a 200 mR input
exposure. The proposed full field digital mammography system can potentially provide improved image quality at reduced
patient dose.
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Shikhaliev, P. M., NIM, A369(1),(1996),p.147-50.
Shikhaliev, P. M. and S. Molloi, NIM, A487,(2002),p.676-85.