Onoguchi M, Maruno H, Fujinaga T, Komiyama N, Takayama T, Murata H
School of Health Sciences, Kanazawa University, Japan.
J Nucl Med Technol. 1997 Sep;25(3):181-6.
Technetium-99m-MIBI uptake was compared between ECG-gated and ungated SPECT images in 10 normal subjects and 10 patients with coronary artery disease to investigate the effects of wall motion on regional myocardial uptake.
Left ventricular ejection fraction (LVEF) and wall motion were evaluated using the first-pass data acquired immediately after injection of 1110 MBq 99mTc-MIBI. A transaxial ungated image was reconstructed with cumulative data during a cardiac cycle. For transaxial gated images, data during a cardiac cycle were divided into eight frames and the first seven frames were used. The lateral/septal ratios for ungated and gated images were obtained using the counts in the ROIs drawn in the lateral and the septal walls.
In 10 normal subjects, the lateral/septal ratio for gated increased during end-systole. The mean of the lateral/septal ratio was significantly lower for ungated than for gated (1.025 vs. 1.077, p < 0.05). In patients with septal wall asynergy and a normokinetic lateral wall, the mean of the lateral/septal ratios was significantly lower for ungated than for gated (1.267 vs. 1.325, p < 0.01).
Ungated SPECT acquisition may underestimate regional myocardial uptake when myocardial wall motion is good, therefore, ECG-gated data should be acquired for accurate assessment of regional myocardial uptake of 99mTc-MIBI.
在10名正常受试者和10名冠心病患者中，比较了心电图门控和非门控单光子发射计算机断层扫描（SPECT）图像中锝-99m-甲氧基异丁基异腈（MIBI）的摄取情况，以研究室壁运动对局部心肌摄取的影响。
使用注射1110MBq 99mTc-MIBI后立即采集的首过数据评估左心室射血分数（LVEF）和室壁运动。用心动周期期间的累积数据重建横轴位非门控图像。对于横轴位门控图像，将心动周期期间的数据分为8帧，并使用前7帧。使用在侧壁和间隔壁绘制的感兴趣区（ROI）中的计数获得非门控和门控图像的侧壁/间隔壁比值。
在10名正常受试者中，门控图像的侧壁/间隔壁比值在收缩末期增加。非门控图像的侧壁/间隔壁比值平均值显著低于门控图像（1.025对1.077，p<0.05）。在间隔壁运动不协调而侧壁运动正常的患者中，非门控图像的侧壁/间隔壁比值平均值显著低于门控图像（1.267对1.325，p<0.01）。
当心肌壁运动良好时，非门控SPECT采集可能会低估局部心肌摄取，因此，应为准确评估99mTc-MIBI的局部心肌摄取采集心电图门控数据。
