Gated SPECT evaluation of left ventricular function using a CZT camera and a fast low-dose clinical protocol: comparison to cardiac magnetic resonance imaging
Gated SPECT evaluation of left ventricular function using a CZT camera and a fast low-dose clinical protocol: comparison to cardiac magnetic resonance imaging
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DOI：
10.1007/s00259-013-2505-9
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发表时间：
2013-12-01
影响因子：
9.1
通讯作者：
Marzullo, Paolo
中科院分区：
文献类型：
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作者：
Giorgetti, Assuero;Masci, Pier Giorgio;Marzullo, Paolo
目的CZT技术允许超快低剂量心肌灌注显像，但其评估左心室功能的准确性仍有待defined.Methods研究组包括55例患者（23名女性，平均年龄63 +/- 9岁）的心肌灌注显像。使用CZT相机（Discovery NM 530 c; GE Healthcare）和低剂量Tc-99 m-tetrofosmin临床方案（平均剂量264 +/-38MBq）在休息时研究患者。放射性示踪剂注射后15分钟，以6分钟列表模式采集进行门控SPECT成像。在Xeleris工作站（GE Healthcare）上使用Lister软件重新格式化图像（8帧至16帧），然后使用专用迭代算法重建。使用定量门控SPECT（QGS）软件进行分析。在2周内，患者接受了心脏磁共振成像（cMRI，1.5-T单位CVi; GE Healthcare），使用30帧采集协议和专用软件进行分析结果用8帧QGS获得的心室体积与cMRI体积显示出良好的相关性（舒张末期容积（EDV），r=0.90;收缩末期容积（ESV），r=0.94; p < 0.001）。然而，QGS显著低估了心室容积（平均差异：EDV，-39.5 +/- 29 mL; ESV，-15.4 +/- 22 mL; p < 0.001）。类似地，使用16帧QGS获得的心室容积显示出与cMRI容积的良好相关性（EDV，r=0.92; ESV，r=0.95; p < 0.001），但存在显著低估（平均差异：EDV，-33.2 +/- 26 mL; ESV，-17.9 +/- 20 mL; p < 0.001）。尽管数值显著较低（47.9 +/-16% vs. 51.2 +/-15%，p < 0.008），但8帧QGS平均射血分数（EF）与cMRI值密切相关（r = 0.84，p < 0.001）。16帧QGS的平均EF显示与cMRI值的最佳相关性（r = 0.91，p < 0.001），与平均cMRI值相似（49.6 +/-16%，p不显著）。区域分析显示8帧和16帧QGS与cMRI室壁运动评分指标具有良好的相关性（8帧WMSI，r = 0.85; 16帧WMSI，r = 0.89; p < 0.01）。与8帧图像相比，16帧重新格式化图像的EF估计似乎更准确。
Purpose CZT technology allows ultrafast low-dose myocardial scintigraphy but its accuracy in assessing left ventricular function is still to be defined.Methods The study group comprised 55 patients (23 women, mean age 63 +/- 9 years) referred for myocardial perfusion scintigraphy. The patients were studied at rest using a CZT camera (Discovery NM530c; GE Healthcare) and a low-dose Tc-99m-tetrofosmin clinical protocol (mean dose 264 +/- 38 MBq). Gated SPECT imaging was performed as a 6-min list-mode acquisition, 15 min after radiotracer injection. Images were reformatted (8-frame to 16-frame) using Lister software on a Xeleris workstation (GE Healthcare) and then reconstructed with a dedicated iterative algorithm. Analysis was performed using Quantitative Gated SPECT (QGS) software. Within 2 weeks patients underwent cardiac magnetic resonance imaging (cMRI, 1.5-T unit CVi; GE Healthcare) using a 30-frame acquisition protocol and dedicated software for analysis (MASS 6.1; Medis).Results The ventricular volumes obtained with 8-frame QGS showed excellent correlations with the cMRI volumes (end-diastolic volume (EDV), r=0.90; end-systolic volume (ESV), r=0.94; p < 0.001). However, QGS significantly underestimated the ventricular volumes (mean differences: EDV, -39.5 +/- 29 mL; ESV, -15.4 +/- 22 mL; p < 0.001). Similarly, the ventricular volumes obtained with 16-frame QGS showed an excellent correlations with the cMRI volumes (EDV, r=0.92; ESV, r=0.95; p < 0.001) but with significant underestimations (mean differences: EDV, -33.2 +/- 26 mL; ESV, -17.9 +/- 20 mL; p < 0.001). Despite significantly lower values (47.9 +/- 16 % vs. 51.2 +/- 15 %, p < 0.008), 8-frame QGS mean ejection fraction (EF) was closely correlated with the cMRI values (r = 0.84, p < 0.001). The mean EF with 16-frame QGS showed the best correlation with the cMRI values (r = 0.91, p < 0.001) and was similar to the mean cMRI value (49.6 +/- 16 %, p not significant). Regional analysis showed a good correlation between both 8-frame and 16-frame QGS and cMRI wall motion score indexes (8-frame WMSI, r = 0.85; 16-frame WMSI, r = 0.89; p < 0.01).Conclusion Low-dose gated SPECT with a CZT camera provides ventricular volumes that correlate well with cMRI results despite significant underestimation in the measure values. EF estimation appeared to be more accurate with 16-frame reformatted images than with 8-frame images.