Wang Tao, Gong Yi, Shi Yibing, Hua Rong, Zhang Qingshan
CT Room, Xuzhou Central Hospital, Xuzhou, Jiangsu 221009, P.R. China.
Department of Ultrasound, Xuzhou Central Hospital, Xuzhou, Jiangsu 221009, P.R. China.
Exp Ther Med. 2017 Jul;14(1):163-168. doi: 10.3892/etm.2017.4451. Epub 2017 May 11.
The feasibility of application of low-concentration contrast agent and low tube voltage combined with iterative reconstruction in whole brain computed tomography perfusion (CTP) imaging of patients with acute cerebral infarction was investigated. Fifty-nine patients who underwent whole brain CTP examination and diagnosed with acute cerebral infarction from September 2014 to March 2016 were selected. Patients were randomly divided into groups A and B. There were 28 cases in group A [tube voltage, 100 kV; contrast agent, iohexol (350 mg I/ml), reconstructed by filtered back projection] and 31 cases in group B [tube voltage, 80 kV; contrast agent, iodixanol (270 mg I/ml), reconstructed by algebraic reconstruction technique]. The artery CT value, signal-to-noise ratio (SNR), contrast-to-noise ratio (CNR), dose length product, effective dose (ED) of radiation and brain iodine intake of both groups were measured and statistically analyzed. Two physicians carried out kappa (κ) analysis on the consistency of image quality evaluation. The difference in subjective image quality evaluation between the groups was tested by χ. The differences in CT value, SNR, CNR, CTP and CT angiography subjective image quality evaluation between both groups were not statistically significant (P>0.05); the diagnosis rate of the acute infarcts between the two groups was not significantly different; while the ED and iodine intake in group B (dual low-dose group) were lower than group A. In conclusion, combination of low tube voltage and iterative reconstruction technique, and application of low-concentration contrast agent (270 mg I/ml) in whole brain CTP examination reduced ED and iodine intake without compromising image quality, thereby reducing the risk of contrast-induced nephropathy.
探讨低浓度对比剂与低管电压联合迭代重建技术在急性脑梗死患者全脑CT灌注（CTP）成像中的应用可行性。选取2014年9月至2016年3月期间行全脑CTP检查并诊断为急性脑梗死的59例患者。将患者随机分为A、B两组。A组28例[管电压100 kV；对比剂为碘海醇（350 mg I/ml），采用滤波反投影法重建]，B组31例[管电压80 kV；对比剂为碘克沙醇（270 mg I/ml），采用代数重建技术重建]。测量并统计分析两组的动脉CT值、信噪比（SNR）、对比噪声比（CNR）、剂量长度乘积、辐射有效剂量（ED）及脑碘摄取量。两名医师对图像质量评估的一致性进行kappa（κ）分析。采用χ检验比较两组主观图像质量评估的差异。两组间CT值、SNR、CNR、CTP及CT血管造影主观图像质量评估差异均无统计学意义（P>0.05）；两组急性梗死灶诊断率差异无统计学意义；而B组（双低剂量组）的ED和碘摄取量低于A组。综上所述，在全脑CTP检查中，低管电压与迭代重建技术相结合，应用低浓度对比剂（270 mg I/ml）可降低ED和碘摄取量，且不影响图像质量，从而降低对比剂肾病的发生风险。
