Killius J S, Nelson R C
Department of Radiology, Duke University Medical Center, Erwin Road, Box 3808, Durham, NC 27710, USA.
Abdom Imaging. 2000 Nov-Dec;25(6):643-50. doi: 10.1007/s002610000053.
Multisection helical computed tomography (CT) has the potential for providing data sets with better section profiles, more anatomic coverage, and shorter breath-holding periods. Our purpose was to quantitate these advantages in a clinical setting when imaging the abdomen and pelvis.
CT parameters including collimation, timing, z-axis coverage, and milliamperes were gathered retrospectively for the image set of both single-section (GE CT/i with 0.8-s rotation) and four-section (GE QX/i Lightspeed with 0.8-s rotation) helical CT scanners. Data were recorded for the abdomen and pelvis CT (n = 30 each), dual-phase liver CT including the pelvis (n = 15 each), and dual-phase pancreas CT (n = 15 each).
The abdominal and pelvic CT averaged 128.4 +/- 5.4 s for single-section scanners (70-s delay, two breath-holds of 21.1 and 17. 7 s with a 19.5-s interscan delay) and 92.2 +/- 2.2 s for the four-section scanner (70-s delay and a 22.2-s breath-hold; p < 0. 0001). For the dual liver and pelvis CT, single-section scanners averaged 119.9 +/- 7.5 s (30-s delay, 15.8-s arterial phase, 20.0-s interscan delay, 21.2-s venous phase, 19.5-s interscan delay, and 14. 2 s for the remaining abdomen and pelvis), whereas the four-section scanner averaged 86.8 +/- 2.5 s (30-s delay, 6.7-s arterial phase, 27.9-s interscan delay, and 21.8-s venous phase including the pelvis; p < 0.0001). For the dual pancreas CT, single-section scanners averaged 86.7 +/- 2.5 s (20-s delay, 28.3-s arterial phase, 17.8-s interscan delay, 21.7-s venous phase), whereas the four-section scanner averaged 78.0 +/- 2.9 s (20-s delay, 9.7-s arterial phase, 30.7-s interscan delay, 13.0-s venous phase; p < 0. 0001).
CT scanners having four-section technology can reduce overall data acquisition times by 10-30% and total milliamperes by 50-60% depending on the protocol with thinner slice profiles.
多层螺旋计算机断层扫描（CT）有潜力提供具有更好断层图像、更大解剖覆盖范围和更短屏气时间的数据集。我们的目的是在临床环境中对腹部和骨盆进行成像时，对这些优势进行量化。
回顾性收集单排螺旋CT扫描仪（GE CT/i，旋转时间0.8秒）和四排螺旋CT扫描仪（GE QX/i Lightspeed，旋转时间0.8秒）图像集的CT参数，包括准直、扫描时间、z轴覆盖范围和毫安量。记录腹部和骨盆CT（各30例）、包括骨盆的肝脏双期CT（各15例）以及胰腺双期CT（各15例）的数据。
单排螺旋CT扫描仪进行腹部和骨盆CT扫描平均用时128.4±5.4秒（延迟70秒，屏气2次，分别为21.1秒和17.7秒，两次扫描间隔19.5秒），四排螺旋CT扫描仪平均用时92.2±2.2秒（延迟70秒，屏气22.2秒；p<0.0001）。对于肝脏和骨盆双期CT，单排螺旋CT扫描仪平均用时119.9±7.5秒（延迟30秒，动脉期15.8秒，扫描间隔20.0秒，静脉期21.2秒，扫描间隔19.5秒，其余腹部和骨盆用时14.2秒），而四排螺旋CT扫描仪平均用时86.8±2.5秒（延迟30秒，动脉期6.7秒，扫描间隔27.9秒，包括骨盆的静脉期21.8秒；p<0.0001）。对于胰腺双期CT，单排螺旋CT扫描仪平均用时86.7±2.5秒（延迟20秒，动脉期28.3秒，扫描间隔17.8秒，静脉期21.7秒），而四排螺旋CT扫描仪平均用时78.0±2.9秒（延迟20秒，动脉期9.7秒，扫描间隔30.7秒，静脉期13.0秒；p<0.0001）。
四排螺旋CT技术的扫描仪可根据扫描方案及更薄的断层图像，将整体数据采集时间减少10% - 30%，总毫安量减少50% - 60%。
