Hardie Andrew D, Mayes Nicholas, Boulter Daniel J
Department of Radiology and Radiological Sciences, Medical University of South Carolina, Charleston, SC 29425, USA.
J Comput Assist Tomogr. 2011 May-Jun;35(3):353-5. doi: 10.1097/RCT.0b013e31821a02c8.
Increasing image pitch in computed tomographic (CT) imaging is a method through which scan time can be reduced, which can reduce motion artifacts. In this study, we assess the clinical feasibility of ultrahigh-pitch CT imaging made possible by dual-source CT.
Image pitch, total scan time, and image quality assessments were compared between 45 patients who underwent a high-pitch dual-source CT and 34 patients imaged by standard CT technique. Image noise and diagnostic image quality were assessed by 2 independent blinded readers on a 5-point scale.
Mean pitch of high-pitch CT was 2.5 (mean scan time, 1.9 seconds) compared with the standard CT mean pitch of 0.6 (mean scan time, 9.8 seconds). There was no statistically significant difference in image noise between high-pitch CT (12.6) and standard CT (12.0); P > 0.3. Although reader 1 rated standard CT as superior to high-pitch CT (P 0.005), reader 2 rated no significant difference. No high-pitch CT studies were rated as limited diagnostically by either reader.
High-pitch dual-source CT can reduce scan time while leading to minor losses of image quality, which may be useful in some patients.
在计算机断层扫描（CT）成像中增加图像螺距是一种可减少扫描时间的方法，进而能够减少运动伪影。在本研究中，我们评估了双源CT实现超高螺距CT成像的临床可行性。
比较了45例行高螺距双源CT检查的患者与34例采用标准CT技术成像的患者的图像螺距、总扫描时间及图像质量评估结果。由2名独立的不知情阅片者采用5分制对图像噪声和诊断图像质量进行评估。
高螺距CT的平均螺距为2.5（平均扫描时间为1.9秒），而标准CT的平均螺距为0.6（平均扫描时间为9.8秒）。高螺距CT（12.6）与标准CT（12.0）的图像噪声无统计学显著差异；P>0.3。虽然阅片者1认为标准CT优于高螺距CT（P=0.005），但阅片者2认为两者无显著差异。两位阅片者均未将任何高螺距CT检查评定为诊断受限。
高螺距双源CT可减少扫描时间，同时导致图像质量略有下降，这在某些患者中可能是有用的。
