Xing J, Shi J, Tong L, Hu H, Jia Y, Ge B, Zhu L, Yu H
Department of Radiology, Shanghai Chest Hospital, School of Medicine, Shanghai Jiao Tong University, Huaihai West Road No. 241, Shanghai 200030, China.
Department of Radiology, Shanghai East Hospital, School of Medicine, Shanghai Tong Ji University, Jimo Road No. 150, Shanghai 200120, China.
Clin Radiol. 2025 Jul;86:106933. doi: 10.1016/j.crad.2025.106933. Epub 2025 Apr 17.
This study compares image quality, contrast agent dosage, and radiation exposure between an advanced precision scanning technique and traditional computed tomography angiography (CTA) scanning methods of the lower limb.
A cohort of 89 patients with suspected lower limb arterial disease was randomly assigned to precise (A) and traditional (B) CTA scanning. group A used variable helical pitch (VHP), while group B used a standard pitch scanning technique. Computed tomography values and image noise were assessed at five anatomical locations, including the lumbar 4 level (abdominal aorta), iliac artery level, popliteal artery level, ankle joint level, and dorsal foot level in both groups. Signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) were computed for each segment, followed by statistical analysis.
Both subjective (SNR, CNR, and CT values) and objective evaluations (evaluation scores of two radiologists) demonstrated superior image quality of lower extremity arteries in group A. The subjective metric was significantly higher in lower limb CTA, particularly at the ankle and dorsum of foot images (all P<0.001), and the subjective score for group A was 21% higher than that of group B (P<0.05). In terms of patients' radiation dose and contrast agent dosage, group A exhibited a 16.23% reduction in radiation dose and a 12.28% reduction in contrast agent dosage compared to group B, respectively (both P<0.001).
The use of VHP in CTA scanning enhances distal blood vessel visualisation, improves image quality, and reduces radiation exposure and contrast agent consumption, offering substantial clinical benefits.
本研究比较一种先进的精准扫描技术与传统下肢计算机断层血管造影（CTA）扫描方法在图像质量、造影剂用量和辐射暴露方面的差异。
将89例疑似下肢动脉疾病的患者随机分为精准CTA扫描组（A组）和传统CTA扫描组（B组）。A组采用可变螺距螺旋扫描（VHP），B组采用标准螺距扫描技术。在两组患者的五个解剖位置评估CT值和图像噪声，包括腰4水平（腹主动脉）、髂动脉水平、腘动脉水平、踝关节水平和足背水平。计算每个节段的信噪比（SNR）和对比噪声比（CNR），随后进行统计分析。
主观指标（SNR、CNR和CT值）和客观评估（两位放射科医生的评估分数）均显示A组下肢动脉的图像质量更优。下肢CTA的主观指标显著更高，尤其是在踝关节和足背图像上（所有P<0.001），A组的主观评分比B组高21%（P<0.05）。在患者的辐射剂量和造影剂用量方面，A组与B组相比，辐射剂量分别降低了16.23%，造影剂用量分别降低了12.28%（均P<0.001）。
在CTA扫描中使用VHP可增强远端血管可视化，提高图像质量，并减少辐射暴露和造影剂消耗，具有显著的临床益处。
