Germano G, Erel J, Kiat H, Kavanagh P B, Berman D S
Department of Medical Physics and Imaging, Cedars-Sinai Research Institute, Cedars-Sinai Medical Center, Los Angeles, CA 90048, USA.
J Nucl Med. 1997 May;38(5):749-54.
This study investigates the feasibility of routine clinical 201Tl gated perfusion SPECT (gated Tl), and compares quantitative left ventricular ejection fraction (LVEF) and visually-assessed regional wall motion and thickening to analogous values obtained from 99mTc-sestamibi gated perfusion SPECT (gated MIBI).
We studied 121 patients with a rest gated Tl (3-3.5 mCi, 35 sec/ projection/poststress gated MIBI (25-30 mCi, 25 sec/projection) separate dual-isotope protocol on a 90 degrees dual-detector camera. Automatic quantitation of LVEFs was accomplished using previously developed and validated software, while visual scoring of motion and thickening was performed using four-point scales.
Average myocardial counts were lower in gated Tl images (306 +/- 81 counts/pixel) compared to gated MIBI images (789 +/- 237 counts/pixel). The quality of gated Tl images was ranked as excellent, good, fair and poor in 24.0%, 42.1%, 24.8% and 9.1%, respectively, of the patients, compared to 43.0%, 43.8%, 9.1% and 4.1%, respectively, for gated MIBI images. Quantitative-gated Tl and gated MIBI LVEFs correlated well (y = 0.11 + 1.05x, r = 0.918, SEE = 6.35). Possible poststress myocardial stunning may have caused gated Tl LVEFs to overestimate gated MIBI LVEFs by a larger (p = 0.03) amount in ischemic patients (n = 47, y = -0.69 + 1.09x, r = 0.914, s.e.e. = 6.44) compared to nonischemic patients (n = 64, y = -1.58 + 1.05x, r = 0.919, s.e.e. = 5.93), the residual difference in LVEFs for this latter group being likely due to different isotope resolution in conjunction with small left ventricles. Exact agreement between gated Tl and gated MIBI segmental myocardial function in 41 nonischemic patients was 92.2% (kappa = 0.619) and 95.4% (kappa = 0.586) for motion and thickening scores, respectively.
Thallium-201 gated SPECT imaging can be effectively performed on the majority of patients in our clinical environment and offers the opportunity to assess both myocardial perfusion and function using one injection and one imaging sequence, similarly to what is done with 99mTc-based agents.
本研究探讨了常规临床201铊门控灌注单光子发射计算机断层扫描（门控铊）的可行性，并将定量左心室射血分数（LVEF）以及视觉评估的局部室壁运动和增厚情况与从99m锝-甲氧基异丁基异腈门控灌注单光子发射计算机断层扫描（门控MIBI）获得的类似值进行比较。
我们在一台90度双探测器相机上，采用单独的双同位素方案，对121例患者进行了静息门控铊（3 - 3.5毫居里，每投影35秒/负荷后门控MIBI（25 - 30毫居里，每投影25秒）检查。使用先前开发并验证的软件自动定量LVEF，同时使用四点量表对运动和增厚情况进行视觉评分。
与门控MIBI图像（789±237计数/像素）相比，门控铊图像中的平均心肌计数较低（306±81计数/像素）。门控铊图像质量在患者中评为优秀、良好、中等和差的分别占24.0%、42.1%、24.8%和9.1%，而门控MIBI图像相应比例分别为43.0%、43.8%、9.1%和4.1%。定量门控铊和门控MIBI的LVEF相关性良好（y = + 1.05x，r = 0.918，标准误 = 6.35）。与非缺血患者（n = 64，y = - 1.58 + 1.05x，r = 0.919，标准误 = 5.93）相比，缺血患者（n = 47，y = - 0.69 + 1.09x，r = 0.914，标准误 = 6.44）中可能的负荷后心肌顿抑可能导致门控铊LVEF比门控MIBI LVEF高估更大量（p = 0.03），后一组LVEF的残余差异可能是由于不同的同位素分辨率以及小左心室共同导致的。41例非缺血患者中，门控铊和门控MIBI节段性心肌功能在运动和增厚评分方面的完全一致性分别为92.2%（kappa = 0.619）和95.4%（kappa = 0.586）。
在我们的临床环境中，大多数患者均可有效进行201铊门控单光子发射计算机断层扫描成像，并且与基于99m锝的药物一样，通过一次注射和一次成像序列即可评估心肌灌注和功能。
