Kaufman J A, Geller S C, Petersen M J, Cambria R P, Prince M R, Waltman A C
Department of Radiology, Massachusetts General Hospital, Boston 02114.
AJR Am J Roentgenol. 1994 Jul;163(1):203-10. doi: 10.2214/ajr.163.1.8010215.
The purpose of this report is to compare the results of MR imaging, including MR angiography, with the results of conventional angiography in the imaging of abdominal aortic aneurysms (AAA).
Twenty seven nonconsecutive patients with known AAA underwent both MR imaging (including MR angiography) and conventional angiography preoperatively. MR imaging was done before angiography according to the following protocol in all patients: sagittal and coronal T1-weighted images of the abdomen, followed by axial MR angiograms obtained with a multiple overlapping thin-slab acquisition (MOTSA) three-dimensional time-of-flight (3D TOF) volume centered on the renal arteries. Last, coronal MR angiograms were obtained with a dynamic contrast-enhanced 3D TOF volume centered on the aorta. Conventional angiography was subsequently performed in all patients. Data from each study were collected prospectively and analyzed in a blinded manner. For the MR studies, all sequences were used to determine the extent of the AAA and the presence of iliac aneurysms; stenotic disease of the celiac, superior mesenteric, renal, and iliac arteries and the number and location of renal arteries were determined from the MR angiograms. For evaluation of the extent of the aneurysm, results from both techniques were compared with surgical results; otherwise MR angiography was compared with conventional angiography. Confidence intervals for sensitivity and specificity were calculated at the 95% level. The McNemar test was used for comparison of proportions.
MR angiography had a sensitivity of 100% (4/4) and a specificity of 91% (21/23) for the four stenoses of the celiac artery that were greater than 50%. For detection of renal artery stenoses of greater than 50%, present in nine arteries, the sensitivity was 89% (8/9) and specificity was 98% (49/50). MR angiography showed 100% (54/54) of all main renal arteries and 78% (7/9) of all accessory renal arteries seen on conventional angiograms. The proximal extent of the aneurysm was correctly predicted on the basis of MR findings in 100% (26/26) of patients with surgical correlation, compared with 92% (24/26) when conventional angiograms were used. This difference was not statistically significant (p > .1). MR imaging had a sensitivity of 100% (19/19) for detection of isolated aneurysms of the common iliac artery, and MR angiography had a 100% sensitivity (5/5) and specificity (103/103) for detection of stenosis greater than 50% in the common and external iliac arteries. One circumaortic left renal vein was visualized on MR images.
These results suggest that MR angiography may be a useful noninvasive method for determining the presence of coexistent celiac, superior mesenteric, renal, and iliac atherosclerotic disease in patients with AAA.
本报告旨在比较磁共振成像（包括磁共振血管造影）与传统血管造影在腹主动脉瘤（AAA）成像中的结果。
27例已知患有AAA的非连续患者术前均接受了磁共振成像（包括磁共振血管造影）和传统血管造影检查。所有患者均按照以下方案在血管造影前进行磁共振成像检查：腹部矢状位和冠状位T1加权图像，随后以肾动脉为中心通过多层重叠薄层采集（MOTSA）三维时间飞跃（3D TOF）容积采集轴向磁共振血管造影图像。最后，以主动脉为中心通过动态对比增强3D TOF容积采集冠状位磁共振血管造影图像。随后所有患者均接受传统血管造影检查。前瞻性收集每项研究的数据并进行盲法分析。对于磁共振研究，所有序列均用于确定AAA的范围以及髂动脉瘤的存在情况；根据磁共振血管造影确定腹腔干、肠系膜上动脉、肾动脉和髂动脉的狭窄性疾病以及肾动脉的数量和位置。为评估动脉瘤的范围，将两种技术的结果与手术结果进行比较；否则将磁共振血管造影与传统血管造影进行比较。计算95%水平的敏感性和特异性的置信区间。采用McNemar检验比较比例。
对于腹腔干大于50%的四处狭窄，磁共振血管造影的敏感性为100%（4/4），特异性为91%（21/23）。对于9条存在大于50%肾动脉狭窄的检测，敏感性为89%（8/9），特异性为98%（49/50）。磁共振血管造影显示了传统血管造影中所见的所有主要肾动脉的100%（54/54）和所有副肾动脉的78%（7/9）。在100%（26/26）有手术相关性的患者中，根据磁共振检查结果正确预测了动脉瘤的近端范围，而使用传统血管造影时这一比例为92%（24/26）。这种差异无统计学意义（p>.1）。磁共振成像对于检测孤立的髂总动脉瘤的敏感性为100%（19/19），磁共振血管造影对于检测髂总动脉和髂外动脉大于50%的狭窄的敏感性为100%（5/5），特异性为100%（103/103）。在磁共振图像上显示了1条环绕主动脉的左肾静脉。
这些结果表明，磁共振血管造影可能是一种用于确定AAA患者是否并存腹腔干、肠系膜上动脉、肾动脉和髂动脉粥样硬化疾病的有用的非侵入性方法。
