A new correction method combined attenuation correction using a difference of intrinsic dual-energy in 201T1C1 SPECT

我们设计了一种新的校正方法，即利用低能量发射（71keV）和高能量发射（167keV）之间的本征双能差进行衰减校正和利用三能窗（TEW）法对71keV进行康普顿散射校正，因为增强了^<201>TlCl （^<201>Tl）的本征双能差，并将其应用于心脏幻影和心肌灌注SPECT研究。分别从71keV和167keV能量窗获取的SPECT数据计算71keV/167keV的衰减系数比和计数比。将厚度相同的缺损分别置入心肌幻膜内表面前、下2个不同位置。心肌灌注SPECT研究使用^<201>Tl，使用与我们对患者使用的相同的方案。对非衰减-散射(A（-)S(-)）、仅散射(A（-)S(+)）和衰减-散射(A（+)S…More(+)）校正后的图像分别进行目视和定量分析比较。71keV/167keV的适当衰减系数比和计数比分别为2.277和5。在正常心肌幻像中，通过衰减散射(A(+)S（+）校正，INF壁得到改善，整个心肌壁均匀。在ANT和INF缺陷壁幻影中，除缺陷壁外示踪剂分布均匀，所有缺陷均被清晰检测到。在已知或疑似CAD的患者中，通过技术可以清晰地识别缺陷区域，提高了CAD的检出率。提出了一种新的校正方法，即利用本然双能差进行衰减校正和利用三能窗（TEW）法对71keV进行康普顿散射校正相结合，可用于^<201>Tl心肌灌注SPECT研究。这可以减少衰减和分散伪影，并允许更准确地评估已知或疑似CAD的患者。少

We devised a new correction method that combined attenuation correction using a difference of intrinsic dual-energy between lower energy emissions (71keV) and higher energy emissions (167keV) without transmission scan and Compton scatter correction using triple-energy window (TEW) method for 71keV because of enhancing a difference of intrinsic dual-energy in ^<201>TlCl (^<201>Tl), and applied to cardiac phantom and myocardial perfusion SPECT studies.Attenuation coefficients ratio and counts ratio for 71keV/167keV were calculated from SPECT data acquired by energy window of 71keV and 167keV, respectively. Defects with the same thickness were inserted on the inner surface of a myocardial phantom at 2 difference locations: anterior (ANT) and inferior (INF). The myocardial perfusion SPECT studies was performed with ^<201>Tl using the same protocol that we use for patients. The images reconstructed by non-attenuation-scatter (A(-)S(-)), only scatter (A(-)S(+)) and attenuation-scatter (A(+)S … More (+)) correction were compared by visual and quantitative analysis, respectively.The adequate attenuation coefficients ratio and counts ratio for 71keV/167keV were 2.277 and 5, respectively. In the normal myocardial phantom, the INF wall was improved by attenuation-scatter (A(+)S(+)) correction, and the whole of the myocardial wall was uniform.In the ANT and INF defect wall phantom, the tracer distribution except defect wall were uniform, and the all defects were clearly detected. In patients with known or suspected CAD, defect regions were clearly discriminated by technique, the detectability for CAD was improved.It is suggested that a new correction method that combined attenuation correction using a difference of intrinsic dual-energy and Compton scatter correction using triple-energy window (TEW) method for 71keV is useful in ^<201>Tl myocardial perfusion SPECT studies. This may reduce both of attenuation and scatter artifacts, and allow the more accurate assessment of patients with known or suspected CAD. Less