Department of Nuclear Medicine, Royal North Shore Hospital, Faculty of Health Sciences, University of Sydney, Sydney, Australia,
Eur J Nucl Med Mol Imaging. 2014 May;41 Suppl 1:S17-25. doi: 10.1007/s00259-013-2542-4. Epub 2013 Sep 14.
The introduction of combined modality single photon emission computed tomography (SPECT)/CT cameras has revived interest in quantitative SPECT. Schemes to mitigate the deleterious effects of photon attenuation and scattering in SPECT imaging have been developed over the last 30 years but have been held back by lack of ready access to data concerning the density of the body and photon transport, which we see as key to producing quantitative data. With X-ray CT data now routinely available, validations of techniques to produce quantitative SPECT reconstructions have been undertaken. While still suffering from inferior spatial resolution and sensitivity compared to positron emission tomography (PET) imaging, SPECT scans nevertheless can be produced that are as quantitative as PET scans. Routine corrections are applied for photon attenuation and scattering, resolution recovery, instrumental dead time, radioactive decay and cross-calibration to produce SPECT images in units of kBq.ml(-1). Though clinical applications of quantitative SPECT imaging are lacking due to the previous non-availability of accurately calibrated SPECT reconstructions, these are beginning to emerge as the community and industry focus on producing SPECT/CT systems that are intrinsically quantitative.
单光子发射计算机断层成像术（SPECT）/计算机断层摄影（CT）组合设备的引入重新激起了人们对定量 SPECT 的兴趣。过去 30 年来，人们一直在研究减轻 SPECT 成像中光子衰减和散射有害影响的方案，但由于缺乏有关身体密度和光子传输的数据，这些方案一直受到限制，而我们认为这些数据是产生定量数据的关键。随着 X 射线 CT 数据现在的常规应用，已经对产生定量 SPECT 重建的技术进行了验证。尽管与正电子发射断层扫描（PET）成像相比，SPECT 扫描的空间分辨率和灵敏度仍较差，但仍然可以产生与 PET 扫描一样定量的 SPECT 扫描。常规校正应用于光子衰减和散射、分辨率恢复、仪器死时间、放射性衰变和交叉校准，以产生 kBq.ml(-1) 单位的 SPECT 图像。尽管由于以前没有经过精确校准的 SPECT 重建，定量 SPECT 成像的临床应用缺乏，但随着社区和行业专注于生产本质上是定量的 SPECT/CT 系统，这些应用开始出现。
