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，利用较低能量发射(71keV)和较高能量发射(167keV)之间的固有双能量之差进行衰减校正，而不进行透射式扫描，并利用三能窗(Tew)方法对71keV进行康普顿散射校正，这是因为增强了TlCl(^&lt；201&gt；Tl)的固有双能量差，并将其应用于心脏模型和心肌灌注SPECT研究中。在心肌模体的前(ANT)和下(INF)两个不同位置插入相同厚度的缺损区。心肌灌注SPECT研究是使用与我们用于患者的相同方案进行的。无衰减-散射(A(-))S(-)、仅散射(A(-)S(+))和衰减-散射(A(+)S)重建的图像…视觉分析和定量分析分别比较了更多的(+))校正，71keV/167keV的合适衰减系数比和计数比分别为2.277和5。在正常心肌模型中，经衰减-散射(A+)S(+)校正后的INF壁得到改善，整个心肌壁均匀；ANT和INF缺损壁模型中，除缺损壁外的示踪剂分布均匀，所有的缺陷都能清晰地检测到。在已知或疑似冠心病的患者中，通过技术可以清楚地区分缺损区，提高了对CAD的检测能力。建议将固有双能差衰减校正和三能窗康普顿散射校正相结合的71keV校正方法用于心肌灌注SPECT研究。这可能会减少衰减和散射伪影，并允许更准确地评估已知或疑似冠心病的患者。较少

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