低管电压低碘含量对比剂上腹部增强CT检查

目的 探讨低管电压低碘含量对比剂上腹部增强CT检查的应用价值。方法 选取100例接受上腹部增强CT扫描患者，随机分为A组（管电压120 kVp、碘含量300 mgI/ml）、B组（管电压120 kVp、碘含量270 mgI/ml）、C组（管电压100 kVp、碘含量300 mgI/ml）及D组（管电压100 kVp、碘含量270 mgI/ml），各25例；均采用40%ASiR算法和FBP算法混合图像重建。测量并分析各组门静脉期图像相同部位CT值、CNR、图像噪声、容积CT剂量指数（CTDIvol）。按4分制对所得图像进行总体图像质量评价，并进行组间比较。分析CT诊断与病理结果的符合率。结果 D组与A组比较，腹主动脉CT值、肝实质CT值、CNR_腹主动脉、CNR_肝实质、噪声差异均无统计学意义（P均>0.05）。A、B、C、D组CTDIvol分别为15.73±5.59、15.34±4.20、12.57±2.55、11.23±2.57，D组与A组比较差异有统计学意义（P<0.05）。4组CT诊断符合率分别为95.45%、90.00%、90.48%、90.91%。4组图像主观评分一致性良好。CT诊断符合率分别为95.45%、90.00%、90.48%、90.91%（P>0.05）。结论 采用低管电压（100 kVp）结合低碘含量（270 mgI/ml）对比剂行上腹部增强CT检查，所得图像质量符合诊断要求，且可降低X线辐射剂量。

Low tube voltage and low-concentration iodinated contrast agent in upper abdomen enhanced CT

Objective To explore the value of low tube voltage and low-concentration iodinated contrast agent in upper abdomen enhanced CT. Methods Totally 100 patients were randomly divided into 4 groups (each n=25) and underwent upper abdomen enhanced CT examination with different scan protocols. The tube voltage and concentration of iodine were 120 kVp and 300 mgI/ml for group A, 120 kVp and 270 mgI/ml for group B, 100 kVp and 300 mgI/ml for group C and 100 kVp and 270 mgI/ml for group D. All CT images were reconstructed by using 40%ASiR and FBP algorithm. The imaging quality was evaluated and visually categorized into 4-point scores. CNR and volume CT dose index (CTDIvol) were calculated. The accuracy of CT diagnosis was evaluated according to pathology results. Results No significant difference of CT value, CNR nor image noise value was found between group A and D (all P>0.05). CTDIvol was (15.73±5.59)mGy in group A, (15.34±4.20)mGy in group B, (12.57±2.55)mGy in group C and (11.23±2.57)mGy in group D. CTDIvol of group D and A were statistically different (P<0.05). CT diagnostic accuracy of 4 groups was 95.45%, 90.00%, 90.48% and 90.91%, respectively. High consistency of image quality scores was obtained between two radiologists. Conclusion Using 100 kVp and 270 mgI/ml iodine agent in upper abdomen enhanced CT examination can obtain diagnostic image quality with low radiation dose.