PIXSCAN: Pixel Detector CT-Scanner for Small Animal Imaging

Abstract

The PIXSCAN is a small animal CT-scanner based on hybrid pixel detectors. These detectors provide very large dynamic range of photons counting at very low detector noise. They also provide high counting rates with fast image readout. Detection efficiency can be optimized by selecting the sensor medium according to the working energy range.Indeed, the use of CdTe allows a detection efficiency of 100% up to 50 keV. Altogether these characteristics are expected to improve the contrast of the CT-scanner, especially for soft tissues, and to reduce both the scan duration and the absorbed dose. A proof of principle has been performed by assembling into a PIXSCAN-XPAD2 prototype the photon counting pixel detector initially built for detection of X-ray synchrotron radiations. Despite the relatively large pixel size of this detector (330 x 330 µm 2 ), we can present 3D tomographic reconstruction of mice at good contrast and spatial resolution. A new photon counting chip (XPAD3) is designed in sub-micronique technology to achieve 130 x 130 µm 2 pixels. This improved circuit has been equipped with an energy selection circuit to act as a band-pass emission filter.Furthermore, the PIXSCAN-XPAD3 hybrid pixel detectors will be combined with the Lausanne ClearPET scanner demonstrator. CT image reconstruction in this non-conventional geometry is under study for this purpose.PACs:

Performance of a Medipix3RX Spectroscopic Pixel Detector With a High Resistivity Gallium Arsenide Sensor

“…M ANY scientific fields depend on the availability of high-quality semiconductor pixel detectors, such as high energy physics [1], [2] or X-ray applications like crystallography [3]- [5], materials science [6], [7], and medical imaging [8]- [10]. These detectors offer good spatial resolution in the order of tens of microns, fast readout speed, and high signal-to-noise ratios (SNRs) [11], [12].…”

Study of L-Glutamic Acid in Solid State for its Possible Use as a Gamma Dosimeter at Different Temperatures (77, 195 and 295 K)

“…Hybrid pixel detectors are getting started to be used in medical research in the last few years [1] [2], they have important advantages to be use in the field. Timepix is a hybrid pixel detector developed by CERN collaboration for particle detections [3].…”

XPAD3: A new photon counting chip for X-ray CT-scanner

“…By illustration, Medipix [1] or PIXSCAN are quantum X-Ray imagers. PIXSCAN is a 44 cm 2 hybrid-pixels imager based on the full custom XPAD chip developed at CPPM [2].…”