不同管电压对肺部占位性病变CT扫描质量及辐射剂量的影响

Effects of different tube voltages on CT scanning quality and radiation dose of pulmonary space-occupying lesions

目的 探讨不同管电压对肺部占位性病变电子计算机断层扫描(CT)扫描质量及辐射剂量的影响。方法 选取2018年8月至2020年8月本院收治的60例肺部占位性病变患者,按照交替分组法分为3组,每组20例。A组采用80 kVp管电压进行扫描,B组采用100 kVp管电压进行扫描,C组以120 kVp管电压进行扫描。对3组预设5个噪声指数(NI)级别进行扫描,比较3组图像质量[信噪比(SNR)、对比噪声比(CNR)、客观噪声(SD)及主观评分]、评价肺部站位性疾病辐射剂量[容积CT剂量指数(CTDIvol)、剂量长度乘积(DLP)、有效辐射剂量(ED)]。结果 A组SD、SNR、CNR均高于C组(P<0.05),A组主观评分低于B组、C组,且B组低于C组(P<0.05),3组图像质量比较差异有统计学意义(P<0.05)。A组CTDIvol、DLP及ED低于B组、C组,且B组低于C组,差异有统计学意义(P<0.05)。结论 与100 kVp、120 kVp管电压相比,80 k Vp管电压应用于肺部占位性病变CT扫描中能获得较好的图像质量,且可明显减少辐射剂量,患者临床获益更高。

Objective To explore the influence of different tube voltages on the scanning quality and radiation dose of computerized tomography(CT) of pulmonary space-occupying lesions. Methods From August 2018 to August 2020, 60 patients with pulmonary space-occupying lesions were selected and divided into three groups according to the alternate grouping method, with 20 cases in each group. Group A was scanned with 80kVp tube voltage, group B with 100 kVp tube voltage and group C with 120 kVp tube voltage. Scan five preset noise index(NI) levels in three groups, compare the image quality of three groups signal-to-noise ratio [SNR], contrast noise ratio [CNR], objective noise [SD] and subjective score, and evaluate the radiation dose of lung standing diseases(volume CT dose index [CTDIvol], dose length product [DLP] and effective radiation dose [ED]). Results SD, SNR, and CNR in group A were higher than those in group C(P<0.05). The subjective scores in group A were lower than those in group B and group C, and group B was lower than group C(P<0.05). There were statistically significant differences in image quality among the three groups(P<0.05). CTDIvol, DLP and ED of group A were lower than those of group B and group C, and group B was lower than that of group C, and the difference was statistically significant(P<0.05). Conclusion Compared with 100 kVp and 120 kVp tube voltages, the application of 80 kVp tube voltage in CT scanning of pulmonary space-occupying lesions can obtain better image quality, significantly reduce the radiation dose, and make patients benefit more clinically.