Arai Takehiro, Kondo Takeshi, Morita Hitomi, Sano Tomonari, Matsutani Hideyuki, Sekine Takako, Shigoka Noriko, Orihara Tadaaki, Kondo Makoto, Kodama Takahide, Ooida Akitsugu, Takase Shinichi
Department of Radiological Technology, Takase Clinic.
Nihon Hoshasen Gijutsu Gakkai Zasshi. 2010 Sep 20;66(9):1204-12. doi: 10.6009/jjrt.66.1204.
Although it is well known that we usually cannot acquire a high quality coronary MDCT in patients with arrhythmia or incomplete breath-hold, we sometimes also cannot obtain a high quality coronary MDCT in patients without arrhythmia or incomplete breath-hold.
We studied what factors other than arrhythmia or incomplete breath-hold affected image quality.
Coronary MDCT and echocardiography were performed within one month in 2145 patients, and 452 cases of arrhythmia or 102 cases of incomplete breath-hold during scanning were eliminated. The remaining 1591 patients were studied. Those patients were divided into two groups (mid-diastolic phase reconstruction (MD) group (N=1377) and end-systolic phase reconstruction (ES) group (N=214)). Age, body weight, mean heart rate (HR) during scanning, temporal resolution (TR) and left ventricular ejection fraction (LVEF) by echocardiography were estimated. Image quality (A: Excellent (3 points), B: Acceptable (2 points), C: Unacceptable (1 point)) was evaluated.
The mean image quality points of the MD group (2.9±0.3) were significantly (P<0.0001) higher than the mean image quality points of the ES group (2.3±0.7), and the mean HR of the MD group (57±6 bpm) was significantly (P<0.0001) lower than that of the ES group (81±15 bpm). In the MD group, HR and TR were selected as significant factors affecting image quality by stepwise regression analysis. In the ES group, TR and HR were selected. In the ES subgroup with HR<90 bpm, TR and HR were selected; however, in the ES subgroup with HR≥90 bpm, TR and LVEF were selected.
In the MD group, low HR was important for high quality coronary MDCT. In the ES subgroup with HR<90, short TR and low HR were important; however, in the ES subgroup with HR≥90 bpm, TR and LVEF were more important than HR.
虽然众所周知，在有心律失常或屏气不完全的患者中我们通常无法获得高质量的冠状动脉MDCT图像，但在没有心律失常或屏气不完全的患者中有时也无法获得高质量的冠状动脉MDCT图像。
我们研究了除心律失常或屏气不完全之外还有哪些因素会影响图像质量。
对2145例患者在1个月内进行冠状动脉MDCT和超声心动图检查，排除扫描期间发生心律失常的452例或屏气不完全的102例。对其余1591例患者进行研究。将这些患者分为两组（舒张中期重建（MD）组（N = 1377）和收缩末期重建（ES）组（N = 214））。评估年龄、体重、扫描期间的平均心率（HR）、时间分辨率（TR）以及超声心动图测得的左心室射血分数（LVEF）。评估图像质量（A：优秀（3分），B：可接受（2分），C：不可接受（1分））。
MD组的平均图像质量得分（2.9±0.3）显著高于ES组（2.3±0.7）（P<0.0001），MD组的平均HR（57±6次/分钟）显著低于ES组（81±15次/分钟）（P<0.0001）。在MD组中，通过逐步回归分析选择HR和TR作为影响图像质量的重要因素。在ES组中，选择TR和HR。在HR<90次/分钟的ES亚组中，选择TR和HR；然而，在HR≥90次/分钟的ES亚组中，选择TR和LVEF。
在MD组中，低HR对高质量冠状动脉MDCT很重要。在HR<90的ES亚组中，短TR和低HR很重要；然而，在HR≥90次/分钟的ES亚组中，TR和LVEF比HR更重要。
