Impact of Blurring Correction Method in Quantitative Image Analysis Using Energy-Resolving Photon Counting Detector (ERPCD)

Energy-resolving photon-counting detectors (ERPCDs) can generate quantitative images represented in a color scale in addition to qualitative gray-scale images. Among these quantitative images, the effective atomic number (Zeff) image stands out as particularly useful for medical diagnosis. However, when individual energy images are affected by image blurring, correct attenuation information cannot be determined, and therefore the calculated Zeff value will differ from the true value. In this chapter, we demonstrate the importance of correcting image blurring in quantitative image analysis using ERPCDs and explain a novel method for correcting image blurring. The newly developed blurring correction method differs from conventional edge enhancement processing, and it can correct the blurring of each energy image to the true value. The usefulness of our correction method was verified through simulations. We also showed that our method can be applied to images generated by our scanogram-type ERPCD as well as to images acquired with commercial photon-counting-type computed tomography equipment.