Chen Yu, Zhang Xiaobo, Xue Huadan, Zhu Yuanli, Wang Yun, Li Yumei, Zhang Zhuhua, Jin Zhengyu
Department of Radiology, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, No.1 Shuai Fu Yuan, Dong Cheng District, Beijing, 100730, China.
Neuroradiology. 2017 Nov;59(11):1071-1081. doi: 10.1007/s00234-017-1901-4. Epub 2017 Aug 24.
This study was conducted in order to evaluate the image quality of 70 kVp and 25 mL contrast medium (CM) volume for head and neck computed tomographic angiography (CTA) and assess the diagnostic accuracy for arterial stenosis.
Fifty patients were prospectively divided into two groups randomly: group A (n = 25), 70 kVp with 25 mL CM, and group B (n = 25), 100 kVp with 40 mL CM. CT attenuation values, noise, signal-to-noise ratio (SNR), and contrast-to-noise ratio (CNR) of the shoulder, neck, and cerebral arteries were measured for objective image quality. Subjective image quality of the shoulder and cerebral arteries was also evaluated. For patients undergoing digital subtracted angiography (DSA), diagnostic accuracy of CTA was assessed with DSA as reference standard.
The SNRs of the shoulder, neck, and cerebral arteries in group A were higher than those in group B (P < 0.05). The CNRs of the shoulder and neck arteries in group A were higher than those in group B (P < 0.05). There was no significant difference in subjective image quality of arteries between group A and group B (P > 0.05). The accuracy was noted as 94.0% (156/166) in group A and 97.1% (134/138) in group B for ≥ 50% stenosis. The accuracy of intracranial arterial stenosis was lower than that of extracranial arterial stenosis in group A. The radiation dose of group A was significantly decreased by 56% than that of group B.
Head and neck CTA at 70 kVp using 25 mL CM can obtain diagnostic image quality with lower radiation dose while maintaining high accuracy in detecting the arterial stenosis compared with the 100-kVp and 40-mL CM.
本研究旨在评估70 kVp管电压及25 mL对比剂用量用于头颈部计算机断层血管造影（CTA）时的图像质量，并评估其对动脉狭窄的诊断准确性。
前瞻性地将50例患者随机分为两组：A组（n = 25），采用70 kVp管电压及25 mL对比剂；B组（n = 25），采用100 kVp管电压及40 mL对比剂。测量肩部、颈部及脑动脉的CT衰减值、噪声、信噪比（SNR）及对比噪声比（CNR），以客观评估图像质量。同时评估肩部及脑动脉的主观图像质量。对于接受数字减影血管造影（DSA）的患者，以DSA为参考标准评估CTA的诊断准确性。
A组肩部、颈部及脑动脉的SNR高于B组（P < 0.05）。A组肩部及颈部动脉的CNR高于B组（P < 0.05）。A组与B组动脉主观图像质量差异无统计学意义（P > 0.05）。对于≥50%的狭窄，A组的准确性为94.0%（156/166），B组为97.1%（134/138）。A组颅内动脉狭窄的准确性低于颅外动脉狭窄。A组的辐射剂量比B组显著降低了56%。
与100 kVp管电压及40 mL对比剂相比，70 kVp管电压及25 mL对比剂用于头颈部CTA时，在保持动脉狭窄检测高准确性的同时，能以较低辐射剂量获得诊断性图像质量。
