Department of Diagnostic and Interventional Radiology, University of Tübingen, Tübingen, Germany.
Acad Radiol. 2010 May;17(5):564-76. doi: 10.1016/j.acra.2009.12.011. Epub 2010 Feb 20.
The aims of this study were to evaluate the effectiveness of low-dose, contrast-enhanced (CE), time-resolved, three-dimensional magnetic resonance angiography (MRA) in the assessment of the abdominal aorta and its major branches at 3 T and to compare the results with those of high-spatial resolution CE MRA.
Twenty-two consecutive patients (eight men, 14 women; mean age, 43.9 +/- 17.9 years) underwent CE time-resolved three-dimensional MRA and high-spatial resolution three-dimensional MRA. Studies were performed using a 3-T magnetic resonance system; gadolinium-based contrast medium was administered at a dose of 3 to 5 mL for time-resolved MRA, followed by 0.1 mmol/kg gadopentetate dimeglumine for single-phase CE MRA. For analysis purposes, the abdominal arterial system was divided into 11 arterial segments, and image quality as well as the presence and degree of vascular pathology were evaluated by two independent magnetic resonance radiologists.
A total of 242 arterial segments were visualized with good image quality. Time-resolved MRA was able to visualize the majority of arterial segments with good definition in the diagnostic range. Vascular pathologies (stenosis, occlusion) or abnormal vascular anatomy was detected in 19 arterial segments, with good interobserver agreement (kappa = 0.78). All image findings were detected with time-resolved CE MRA by both observers and were confirmed by correlative imaging.
Low-dose, time-resolved MRA at 3 T yields rapid and important anatomic and functional information in the evaluation of the abdominal vasculature. Because of its limited spatial resolution, time-resolved MRA is inferior to CE MRA in demonstrating fine vascular details.
本研究旨在评估低剂量、对比增强（CE）、时间分辨、三维磁共振血管造影（MRA）在 3T 下评估腹主动脉及其主要分支的有效性，并将结果与高空间分辨率 CE MRA 进行比较。
连续 22 例患者（8 名男性，14 名女性；平均年龄 43.9±17.9 岁）接受了 CE 时间分辨三维 MRA 和高空间分辨率三维 MRA 检查。研究在 3T 磁共振系统上进行；钆基造影剂剂量为 3 至 5mL 用于时间分辨 MRA，随后使用 0.1mmol/kg 钆喷替酸二甲胺用于单相 CE MRA。为了分析目的，将腹主动脉系统分为 11 个动脉段，由两位独立的磁共振放射科医生评估图像质量以及血管病变的存在和程度。
共有 242 个动脉段具有良好的图像质量。时间分辨 MRA 能够以良好的诊断范围显示大多数动脉段的图像。19 个动脉段检测到血管病变（狭窄、闭塞）或异常血管解剖，观察者间具有良好的一致性（kappa=0.78）。两位观察者均通过时间分辨 CE MRA 检测到所有图像发现，并通过相关成像进行了证实。
3T 下的低剂量、时间分辨 MRA 可快速提供重要的腹部血管解剖和功能信息。由于其空间分辨率有限，时间分辨 MRA 在显示精细的血管细节方面逊于 CE MRA。
