高浓度碘对比剂在重度肥胖患者冠状动脉CTA血管成像中的应用

Application of high concentration iodine contrast medium in coronary angiography for patients with severe obesity

目的探讨高浓度碘对比剂对重度肥胖患者冠状动脉CT血管造影(CTA)图像质量的影响。方法采用随机、对照、前瞻性研究方法,将2018年2~6月首都医科大学附属北京友谊医院收治的52例接受冠脉CTA检查的重度肥胖(BMI≥35kg/m2)患者随机分为A、B两组,每组各26例。两组患者均采用一致的扫描参数。注射碘对比剂总量为80ml,注射流率为5ml/s。A组碘对比剂浓度为400mgI/ml,碘流率(IDR)为2.0gI/s,;B组碘对比剂浓度为350mgI/ml,IDR为1.75gI/s。记录患者的BMI、主动脉根部CT值、客观噪声(SD)、剂量长度乘积(DLP),计算信噪比(SNR)及有效剂量(ED)。对图像进行三维重建处理,采用美国心脏病协会推荐使用的冠状动脉15分段方法进行主观评分。比较两组患者主观评价及客观数据的差异。结果A、B两组患者的图像主动脉根部CT值分别为(392.97±89.22)Hu、(291.81±43.42)Hu,差异具有统计学意义(P<0.05),A组患者的SNR(11.71±2.97)和主观评分(3.62±0.52分)明显高于对照组(8.33±2.11,3.19±0.63分),差异均具有统计学意义(P<0.05)。两组患者的SD及ED差异均无统计学意义(P>0.05)。结论重度肥胖人群(BMI≥35kg/m2)行CTA检查时,采用高浓度对比剂可以提高IDR,在减少注射风险的同时改善强化效果,保证图像质量。

Objective To evaluate the effect of high concentration iodine contrast medium in coronary angiography of CT for patients with severe obesity. Methods This study was a prospective,randomized,controlled study. During February 2018 to June 2018,52 patients in Beijing Friendship Hospital with severe obesity (BMI≥35 kg/m 2) were randomly divided to two groups (group A and group B). Each group had 26 patients. Scanning parameters of the two groups were the same. The volume of contrast medium was 80 ml,and the injection flow rate was 5 ml/s. The concentration of iodine contrast medium for group A was 400 mgI/ml,and the iodine rate (IDR) was 2.0 gI/s. The concentration of iodine contrast medium for group B was 370 mgI/ml,and the iodine rate (IDR) was 1.75 gI/s. We recorded the BMI,CT value of the aortic-root lumen,image noise (SD),dose length product (DLP) of the patients of the two groups;and calculated the signal to noise ratio (SNR) and effective dose (ED). Three-dimensional reconstruction of the image was performed,and the 15-segment coronary artery method recommended by the American heart association was used for subjective scoring. Results The CT value of the aortic-root lumen of patients of group A and group B were (392.97±89.22) Hu and (291.81±43.42) Hu. The difference was statistically significant ( P <0.05). The SNR (11.71±2.97) and subjective score (3.62±0.52 score) of group A patients were significantly higher than those of the control group (8.33±2.11,3.19±0.63 score ).( P <0.05). There were no statistically differences in image noise and the effective radiation dose between the two groups ( P >0.05). Conclusion If patients with severe obesity (BMI≥35 kg/m 2) performed a coronary angiography of CT,the high concentration of contrast medium can be used to improve the IDR,reduce the risk of injection,improve the strengthening effect,and finally ensure the quality of the image.