Evaluation of a Wobbling Method Applied to Correcting Defective Pixels of CZT Detectors in SPECT Imaging.

Zhaoheng Xie,Kun Yang,Baixuan Xu,Qiushi Ren,Suying Li

doi:10.3390/s16060772

Abstract

In this paper, we propose a wobbling method to correct bad pixels in cadmium zinc telluride (CZT) detectors, using information of related images. We build up an automated device that realizes the wobbling correction for small animal Single Photon Emission Computed Tomography (SPECT) imaging. The wobbling correction method is applied to various constellations of defective pixels. The corrected images are compared with the results of conventional interpolation method, and the correction effectiveness is evaluated quantitatively using the factor of peak signal-to-noise ratio (PSNR) and structural similarity (SSIM). In summary, the proposed wobbling method, equipped with the automatic mechanical system, provides a better image quality for correcting defective pixels, which could be used for all pixelated detectors for molecular imaging.

Highlights

Radionuclide imaging has become one of the most advanced molecular imaging techniques to monitor physiological functions [1,2]
The results proved that the proposed wobbling proposed wobbling method provides improvement in image quality of pixelated semiconductor method provides improvement in image quality of pixelated semiconductor detector, especially for detector, especially for the small object imaging with pinhole collimator
We mainly investigate the effect of the wobbling method in the correction of bad pixels that appear in the region of interest (ROI) and appear in the background

Summary

Introduction

Radionuclide imaging has become one of the most advanced molecular imaging techniques to monitor physiological functions [1,2]. Single Photon Emission Computed Tomography (SPECT) images tend to be “noisy” because of the low amount of radiotracer per volume of interest (VOI) and the effect of Compton scattering in tissue and collimators. Semiconductor nuclear radiation detectors, especially cadmium zinc telluride (Cd1 ́x Znx Te, CZT) materials, have been considered as alternatives to scintillator detectors [3,4,5] because of their good stopping power and low dark current [4,6,7]. The major advantage of semiconductor over traditional scintillator detectors is that they can directly convert the deposited photon energy into measurable signals, which could improve energy resolution and detection efficiency [4,5,7,8]. CZT detectors are regarded to be the most promising option for SPECT imaging

Methods

Results

Discussion

Conclusion