Most clinical computed tomography (CT) protocols use helical scanning; however, the traditional method for CTDI_vol measurement replaces the helical protocol with an axial scan, which is not easily accomplished on many scanners and may lead to unmatched collimation settings and bowtie filters. This study assesses whether CTDI_vol can be accurately measured with a helical scan and determines the impact of pitch, collimation width, and excess scan length.

中文翻译：

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螺旋获得的CTDIvol作为传统方法的替代方法。

大多数临床计算机断层扫描（CT）方案都使用螺旋扫描；但是，传统的CTDI_体积测量方法用轴向扫描代替了螺旋协议，这在许多扫描仪上不容易实现，并且可能导致准直设置和领结过滤器不匹配。这项研究评估了CTDI _vol是否可以通过螺旋扫描准确测量，并确定了螺距，准直宽度和多余扫描长度的影响。