摘要
目的:评价成人颅脑低剂量CT平扫的图像质量及临床价值。材料和方法:110例患者被随机分组并运用64层螺旋CT机采用非螺旋扫描方式分别行330mAs、130mAs、100mAs的颅脑平扫,对相应图像进行主观评分、噪声测量和客观评价分析。结果:130mAs和100mAs组小脑和内囊评分均低于侧裂池评分;各组间各相应解剖结构评分均具有统计学差异(P<0.05)。各组内小脑白质噪声大于壳核和半卵圆中心噪声,随着管电流量的降低,各相应层面各解剖结构噪声随之增加(P<0.05)。颅脑平扫CT图像的对比噪声比则随着管电流量的降低而减少(P<0.05),而灰质清晰度无明显变化。相对于330mAs组,130mAs组DLP减少了61%,100mAs组减少了70%。结论:130mAs颅脑平扫CT图像质量可以常规用于成人临床,患者复查可以用100mAs。
Purpose： To analyze the effect of various tube current settings（mAs） and its clinical value for adult cranial CT protocol. Materials and Methods： 110 patients, subdivided into three groups randomly, underwent a cranial non-helical CT scanning with 330-mAs, 130-mAs and 100-mAs, respectively but otherwise the same parameters. Two neuroradiologists visually scored the resulting images for quality in a blinded method and Mann-Whitney U test was used for comparisons. Representative regions of interest were chosen on selective reference levels and image noise, eonspicuity and the contrast-to-noise ratio were acquired. Statistical analyses were done by using Independent-Sample T test. Results： Subjective image scores of visibility of sylvian fissures were higher than that of internal capsules and grey-white differentiation in the cerebellum in 130-mAs and 100-mAs groups. The image scores of the same structures were significantly different between groups （P 〈 0.05 ）. The noises of white matter in the cerebellum were higher than that of putamen and centrum semiovale in every group （ P 〈 0.05 ）. The noises of the same level increased （ P 〈 0.05 ） and the CNR decreased （ P 〈 0.05 ） while conspicuity changed little （ P 〈 0.05 ） with the decrease of mAs. Compared to that of 330-mAs, T DLP of 130-mAs and 100-mAs decreased 60% and 70%, respectively. Conclusion： 130-mAs head CT images can be applied for adult and 100mAs used for follow-up examination.
出处
《中国医学影像学杂志》
CSCD
北大核心
2009年第5期336-339,共4页
Chinese Journal of Medical Imaging
