多层螺旋CT低剂量与图像质量相关性的研究

近年来CT的广泛应用提高了临床诊断的效果。CT机在使用中的主要问题是剂量过大。国家质检总局于2007年8月2日发布JJG1026-2007《医用诊断螺旋计算机断层摄影装置（CT）X射线辐射源》,CT机检定时必须首先满足剂量上限值的要求。从诊断上来说,只有具有较好质量的CT图像才具有诊断意义,不能为达到低剂量的目的而无限地降低扫描条件,而目前我国还没有机构对这一问题开展相关工作。本文为评价CT机的医学诊断性能,讨论了不同的扫描参数（包括kV、mAs、层厚、螺距因子以及准直宽度）对剂量指数和图像质量的影响,达到使患者在受照剂量最少的条件下,实现最优化的图像质量。这一问题更值得有关专业和技术部门参考,从而对病人的辐射剂量控制和医疗诊断质量控制进行有效评估。

The Relativity Study between Low Radiation Dose and Image Quality in Multi-detector Spiral CT

The widespread use of CT in resent years has improved the effect of clinical diagnose. The most important problem in CT using is excessive radiation dose.AQSIQ released the Verification Regulation of JJG 1026- 2007 and lower than dose upper limit was the first target in this regulation. From the view of diagnose; only the CT images of good quality can be useful to doctors. Unlimited reducing the .scanning condition in order to reach the goal of lower dose will affect the image quality inevitably. Different scanning parameters will be analyzed here to find their intluences on dose index and image quality, thus realize the best image quality at the lowest radiation dose level. Correlative institution should pay more attention to this problem in order to make effective apprise on the radiation control for patients as well as improve the quality of diagnose.