Spectroscopic biomedical imaging with the Medipix2 detector

Abstract

This study confirms that the Medipix2 x-ray detector enables spectroscopic bio-medical plain radiography. We show that the detector has the potential to provide new, useful information beyond the limited spectroscopic information of modern dual-energy computed tomography (CT) scanners. Full spectroscopic 3D-imaging is likely to be the next major technological advance in computed tomography, moving the modality towards molecular imaging applications. This paper focuses on the enabling technology which allows spectroscopic data collection and why this information is useful. In this preliminary study we acquired the first spectroscopic images of human tissue and other biological samples obtained using the Medipix2 detector. The images presented here include the clear resolution of the 1.4mm long distal phalanx of a 20 week old miscarried foetus, showing clear energy-dependent variations. The opportunities for further research using the forthcoming Medipix3 detector are discussed and a prototype spectroscopic CT scanner (MARS, Medipix All Resolution System) is briefly described.

Spectroscopic (multi-energy) CT distinguishes iodine and barium contrast material in MICE

“…We established the ability to produce spectroscopic images of a foetal hand and specimen radiography of a breast tumour [13,14]. We then constructed a desktop CT [3] based around the Medipix2 detector [10]; this has a 75-kVp Kevex PXS11-150-75 X-ray tube (Thermo Scientific, Attenuation curves for several elements.…”

Dual- and multi-energy CT: approach to functional imaging

“…Such images are often called spectroscopic or spectral CT [3, 38]. The photon-counting detector technology enables direct conversion of individual X-ray photons into an ionisation cloud within a semi-conductor layer [39]. The detector's electronics then measure the amount of energy deposited by the individual photon and increments a counter associated with that energy.…”

“…The Medipix collaboration, hosted by the European Organisation for Nuclear Research (CERN), has been most public with their developments [39], but recently some of the major equipment manufacturers have also announced projects [40]. …”

X-ray scattering tomography for biological applications

“…Using a spectral detector, conventional gray-scale CT can be improved to true-color imaging. The state of the art detector for x-ray spectroscopy, such as the Medipix detector [14], is a photon counting and energy discriminating device. It records an x-ray signal photon by photon with virtually no detector noise.…”