Feng Ruiqi, Tong Jiajie, Liu Xiaofei, Zhao Yu, Zhang Liang
Department of Radiology, The First Affiliated Hospital of China Medical University, Shenyang 110001, P.R. China.
Department of Radiology, Hebei General Hospital, Shijiazhuang 050051, P.R. China.
Korean J Radiol. 2017 Sep-Oct;18(5):763-772. doi: 10.3348/kjr.2017.18.5.763. Epub 2017 Jul 17.
To evaluate the feasibility and image quality (IQ) of prospectively high-pitch coronary CT angiography (CCTA) with low contrast medium injection rate at 70 kVp.
One hundred and four patients with suspected coronary artery disease (body mass index < 26 kg/m, sinus rhythm and heart rate < 70 beats/min) were prospectively enrolled and randomly divided into two groups. In group A and group B, 28 mL and 40 mL of 370 mgI/mL iodinated contrast media was administrated at a flow rate of 3.5 and 5 mL/s, respectively. CT values, noise, signal-to-noise ratio, contrast-to-noise ratio (CNR) of the proximal segments of coronary arteries and subjective IQ were evaluated.
The CT values and noise in group A were significantly lower than those in group B (434-485 Hounsfield units [HU] vs. 772-851 HU, all < 0.001; 17.8-22.3 vs. 23.3-26.4, all < 0.005). The CNRs of the right coronary artery and left main artery showed no statistical difference between the two groups (42.1 ± 13.8 vs. 36.8 ± 16.0, = 0.074; 38.7 ± 10.6 vs. 38.1 ± 17.0, = 0.819). No statistical difference was observed between the two groups in IQ scores (3.04 ± 0.75 vs. 3.0 ± 0.79, = 0.526) and diagnostic ratio (96.1% [50/52] vs. 94.2% [49/52], = 0.647).
Prospective high-pitch CCTA at 70 kVp with 28 mL of contrast media and injection rate of 3.5 mL/s could provide diagnostic IQ for normal-weight patients with heart rate of < 70 beats/min.
评估在70 kVp下采用低对比剂注射速率进行前瞻性高螺距冠状动脉CT血管造影（CCTA）的可行性和图像质量（IQ）。
前瞻性纳入104例疑似冠心病患者（体重指数<26 kg/m²，窦性心律且心率<70次/分钟），并随机分为两组。A组和B组分别以3.5 mL/s和5 mL/s的流速注射28 mL和40 mL的370 mgI/mL碘化对比剂。评估冠状动脉近端节段的CT值、噪声、信噪比、对比噪声比（CNR）以及主观IQ。
A组的CT值和噪声显著低于B组（434 - 485亨氏单位[HU]对772 - 851 HU，均<0.001；17.8 - 22.3对23.3 - 26.4，均<0.005）。两组右冠状动脉和左主干动脉的CNR无统计学差异（42.1±13.8对36.8±16.0，P = 0.074；38.7±10.6对38.1±17.0，P = 0.819）。两组在IQ评分（3.04±0.75对3.0±0.79，P = 0.526）和诊断率（96.1%[50/52]对94.2%[49/52]，P = 0.647）方面无统计学差异。
对于心率<70次/分钟的正常体重患者，在70 kVp下采用28 mL对比剂、3.5 mL/s注射速率的前瞻性高螺距CCTA可提供诊断性IQ。
