Noschang Julia, Tachibana Adriano, da Silva Viviani Larissa Barsotti, Silva Murilo Marques Almeida, de Almeida Mendes Cynthia, Rocha Marcelo Assis, Ishikawa Walther Yoshiharu, Wolosker Nelson, Szarf Gilberto
Hospital Israelita Albert Einstein, São Paulo, Brazil.
Abdom Radiol (NY). 2025 Jun;50(6):2770-2777. doi: 10.1007/s00261-024-04726-6. Epub 2024 Dec 9.
This study aims to evaluate the image quality of computed tomography (CT) angiograms obtained using a virtual contrast augmentation technique, adding an iodine map to the contrast-enhanced images, obtained through a digital subtraction technique, reducing the dose of intravenous iodinated contrast medium compared to the conventional institutional standard technique.
This prospective investigation enrolled patients previously diagnosed with abdominal aortic aneurysms, who underwent two successive computed tomography angiographies (CTAs) of the aorta. One CTA was performed employing the virtual contrast enhancement boost technique with a 40% decrease in the intravenous contrast medium dose, while the other adhered to the conventional protocol without any reduction in contrast medium volume. After imaging, both qualitative and quantitative assessments were conducted to evaluate the opacification level of the aorta and its branching vessels.
The study analyzed 28 examinations from 14 subjects (two per participant). Qualitative analysis revealed that image quality was deemed adequate for diagnostic purposes, with nearly all arterial segments in both protocols rated as good or excellent. Although no statistically significant differences were detected, the average attenuation across all arterial segments in the angiograms exhibited a trend towards higher values in the virtual contrast enhancement boost technique, compared to the conventional protocol. Similarly, the signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) demonstrated comparable levels between the two methodologies.
The application of virtual contrast enhancement in the acquisition of CT angiograms of the aorta maintains comparable image quality, while reducing the dosage of intravenous contrast medium by 40%. This approach suggests a potential for optimizing contrast use in vascular imaging, aligning with goals related to patient safety and radiological efficiency.
本研究旨在评估使用虚拟对比增强技术获得的计算机断层扫描（CT）血管造影的图像质量，该技术是将碘图添加到通过数字减法技术获得的对比增强图像中，与传统的机构标准技术相比，可减少静脉注射碘化造影剂的剂量。
这项前瞻性研究纳入了先前被诊断为腹主动脉瘤的患者，这些患者接受了两次连续的主动脉计算机断层扫描血管造影（CTA）。一次CTA采用虚拟对比增强技术，静脉造影剂剂量减少40%，而另一次则遵循传统方案，造影剂体积不减少。成像后，进行定性和定量评估，以评估主动脉及其分支血管的显影水平。
该研究分析了14名受试者的28次检查（每位参与者两次）。定性分析表明，图像质量对于诊断目的而言是足够的，两种方案中几乎所有动脉段的评级均为良好或优秀。尽管未检测到统计学上的显著差异，但与传统方案相比，血管造影中所有动脉段的平均衰减在虚拟对比增强技术中呈现出更高值的趋势。同样，两种方法之间的信噪比（SNR）和对比噪声比（CNR）显示出相当的水平。
在主动脉CT血管造影采集过程中应用虚拟对比增强可保持相当的图像质量，同时将静脉造影剂剂量减少40%。这种方法表明在血管成像中优化对比剂使用具有潜力，符合与患者安全和放射学效率相关的目标。
