Shetty A N, Shirkhoda A, Bis K G, Ellwood R, Li D
Department of Radiology, William Beaumont Hospital, Royal Oak, MI 48073-6769, USA.
J Comput Assist Tomogr. 1998 Mar-Apr;22(2):179-85. doi: 10.1097/00004728-199803000-00004.
Our goal was to describe a 3D breath-hold (3D BH) contrast-enhanced MRA technique and apply the technique to patients with known or suspected aortic and iliac artery disease.
A fat-suppressed 3D GRE pulse sequence was designed with a total of 16 partition encodings. This took < 24 s for data acquisition in the abdomen and pelvis and was easily achieved during a single breath-hold. The technique was applied to 26 patients who presented with either known or suspected abdominal aortic or iliac vascular diseases. For comparison, in 19 patients a 2D TOF MRA pulse sequence with a traveling saturation band was used. Angiographic correlation was made in 18 studies.
The 3D BH MRA was easily applicable in the evaluation of vascular anatomy and pathology. In three cases, it was superior to 2D TOF and conventional angiography for visualizing clot within the wall of an aneurysm in the abdominal aorta. In 20 cases, both MRA techniques overestimated the degree of stenosis in the lower peripheral vessels; however, this was more pronounced on 2D TOF. In five cases, the aneurysm wall was clearly defined by 3D BH MRA, whereas there was considerable signal loss in 2D TOF due to complex flow. With 3D BH MRA, the entire vessel territory both in abdominal aorta and in iliac vessels was visualized in all cases without signal falloff in the FOV. Breath-holding provided static images of the vessels that were free of blurring due to respiratory motion.
Preliminary experience suggests that 3D BH with its distinct advantage of speed may serve as a useful screening tool for patients who cannot have conventional angiography or tolerate a lengthy MR examination of the abdominal aorta and iliac arteries.
我们的目标是描述一种三维屏气(3D BH)对比增强磁共振血管造影(MRA)技术,并将该技术应用于已知或疑似主动脉及髂动脉疾病的患者。
设计了一种脂肪抑制三维梯度回波(GRE)脉冲序列,共有16个层面编码。在腹部和盆腔进行数据采集用时不到24秒,且在单次屏气期间很容易实现。该技术应用于26例已知或疑似腹主动脉或髂血管疾病的患者。作为对照,19例患者使用了带有移动饱和带的二维时间飞跃法(TOF)MRA脉冲序列。18项研究进行了血管造影相关性分析。
3D BH MRA很容易应用于血管解剖结构和病变的评估。在3例病例中,对于显示腹主动脉瘤壁内的血栓,它优于二维TOF和传统血管造影。在20例病例中,两种MRA技术都高估了外周下部血管的狭窄程度;然而,二维TOF上这种情况更明显。在5例病例中,3D BH MRA清晰地显示了动脉瘤壁,而二维TOF由于复杂血流出现了相当程度的信号丢失。使用3D BH MRA,所有病例中腹主动脉和髂血管的整个血管区域均清晰显示,视野内无信号衰减。屏气提供了血管的静态图像,避免了因呼吸运动造成的模糊。
初步经验表明,3D BH因其明显的速度优势,对于无法进行传统血管造影或耐受腹主动脉和髂动脉长时间磁共振检查的患者,可能是一种有用的筛查工具。