Department of Electrical and Electronics Engineering, Azrieli College of Engineering, Jerusalem 9103501, Israel.
Shaare Zedek Medical Center, Jerusalem 9103102, Israel.
Sensors (Basel). 2020 May 26;20(11):3013. doi: 10.3390/s20113013.
Biomedical planar imaging using gamma radiation is a very important screening tool for medical diagnostics. Since lens imaging is not available in gamma imaging, the current methods use lead collimator or pinhole techniques to perform imaging. However, due to ineffective utilization of the gamma radiation emitted from the patient's body and the radioactive dose limit in patients, poor image signal to noise ratio (SNR) and long image capturing time are evident. Furthermore, the resolution is related to the pinhole diameter, thus there is a tradeoff between SNR and resolution. Our objectives are to reduce the radioactive dose given to the patient and to preserve or improve SNR, resolution and capturing time while incorporating three-dimensional capabilities in existing gamma imaging systems. The proposed imaging system is based on super-resolved time-multiplexing methods using both variable and moving pinhole arrays. Simulations were performed both in MATLAB and GEANT4, and gamma single photon emission computed tomography (SPECT) experiments were conducted to support theory and simulations. The proposed method is able to reduce the radioactive dose and image capturing time and to improve SNR and resolution. The results and method enhance the gamma imaging capabilities that exist in current systems, while providing three-dimensional data on the object.
使用伽马辐射的生物医学平面成像是医学诊断中非常重要的筛选工具。由于伽马成像中没有透镜成像，因此目前的方法使用铅准直器或针孔技术进行成像。然而，由于从患者体内发射的伽马辐射的利用效率低下以及患者的放射性剂量限制，图像的信噪比（SNR）和图像采集时间都很差。此外，分辨率与针孔直径有关，因此 SNR 和分辨率之间存在权衡。我们的目标是降低给予患者的放射性剂量，并在保留或提高 SNR、分辨率和采集时间的同时，在现有的伽马成像系统中纳入三维能力。所提出的成像系统基于使用可变和移动针孔阵列的超分辨率时分复用方法。在 MATLAB 和 GEANT4 中都进行了模拟，并进行了伽马单光子发射计算机断层扫描（SPECT）实验，以支持理论和模拟。所提出的方法能够降低放射性剂量和图像采集时间，提高 SNR 和分辨率。结果和方法增强了现有系统中的伽马成像能力，同时提供了物体的三维数据。
