扫描采集和重建参数的调整

（116）CT影像应要求总是在最低患者剂量下达到临床检查目的。多时相检查应该限制在可以做出诊断的最少时相，所成像解剖范围也应最小。影像厚度不应该小于必要值，以减少影像噪声，从而避免为补偿增加的噪声水平而增加辐射剂量。对于儿童和身材较小患者，kVp应该尽可能低，AEC应该作为常规使用。对于没有配置AEC的CT，应该在有经验医学物理师的支持下制定一份技术表，并坚持用于所有患者。这一点对于儿科患者CT尤为必要。像在2．4节所描述的诊断参考水平是一个控制患者剂量的很好工具。最终，要求CT成像服务提供者应该将不同患者身材和检查类型的剂量水平和影像质量与诊断参考水平或等同标准进行对照，以确保他们在适当低剂量水平下为患者提供高质量检查。

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