Photon-counting spectral CT

Work with us to develop new CZT-based CT systems

Photon-counting spectral CT

We are helping medical OEMs develop photon-counting spectral CT. There are three different uses for Kromek CZT, represented by three medical imaging applications. They represent a trade-off in performance between energy resolution (% FWHM) and gamma photon flux.

  1. For SPECT gamma cameras and surgical probes, the energy resolution can be very good (< 4.0% at 140 keV) because the photon flux is less than 1,000 photons per second per square mm detector area.
  2. A medium flux x-ray photon application is represented by bone mineral densitometry, where fluxes reach a few million photons per second per square mm area).
  3. The highest fluxes are represented by photon-counting spectral CT where fluxes reach hundreds of millions of x-ray photons per second per square mm detector area. The energy resolution for this colour CT application is approx 15-20% in the clinical range of 80-140 keV peak.

Our photon-counting spectral CT expertise

We have achieved fluxes > 100 million pps/mm2 without polarization of the CZT detector arrays. We are currently working to speed up the readout electronics to avoid pulse pileup and to compensate for inter-pixel charge sharing, including k-escape fluorescence.

What is photon-counting computed tomography (CT)

Photon-counting computed tomography (CT) is a computed tomography technique currently under research and development, both within academia and by major vendors of CT systems. Photon-counting CT has the potential both to offer significant improvements to existing CT imaging techniques and to make possible completely novel applications. A photon-counting CT system employs a photon-counting detector (PCD) which registers the interactions of individual photons. By keeping track of the deposited energy in each interaction, the detector pixels of a PCD each record an approximate energy spectrum, making it a spectral or energy-resolved CT technique. In contrast, typical CT scanners use energy-integrating detectors (EIDs), where the total energy (generally from a large number of photons as well as electronic noise) deposited in a pixel during a fixed period of time is registered. Typical CT detectors thus register only photon intensity, comparable to black-and-white photography, whereas photon-counting detectors register also spectral information, similar to colour photography.
See the full description on Wikipedia.

Work with us to develop products for colour CT using CZT detector arrays.

Related products

Stay up to date with Kromek news

Join our mailing list

Unsure what product you need?

Use our product finder tool