Vanninen R L, Manninen H I, Partanen P K, Tulla H, Vainio P A
Department of Clinical Radiology, Kuopio University Hospital, Finland.
Neuroradiology. 1996 May;38(4):299-305. doi: 10.1007/BF00596574.
Our purpose was to assess the reproducibility of and differences between the most commonly used methods for assessing carotid artery stenosis using magnetic resonance angiography (MRA). We studied 55 patients who underwent axial three-dimensional time-of-flight MRA (1.5 T). Quantitative caliper measurements were performed from maximum intensity projection (MIP) and multiple planar reconstruction (MPR) images, according to the criteria of the North American Symptomatic Carotid Endarterectomy Trial (NASCET) and European Carotid Surgery Trial (ECST). The measurements were compared to each other and to visual interpretation, using conventional angiography as the reference. The measured percentage stenoses were higher on MRA than on digital subtraction angiography (DSA) using both NASCET (mean difference 1.9-3.0%) and ECST (6.3-6.7%) criteria. The kappa coefficients for the agreement between DSA and MRA were higher using the NASCET (0.61-0.76) than the ECST criteria (0.52-0.65). No statistically significant differences were found between measurements from MIP and MPR images. The ECST measurement criteria gave significantly higher percentage stenoses than the NASCET criteria (P < 0.001), this difference being more prominent on MRA (mean difference in diameter stenosis percentage 14.3-16.4%) than on DSA (7.6-11.2%) and most important with mild stenoses. The difference between visual interpretation and quantitative measurements on MRA was significant (P = 0.01-0.001). There were no statistically significant interobserver differences in the MRA film readings, either in visually estimated degrees of stenosis or stenosis measurements. Thus, the different criteria of the two multicentre trials led to significantly different results, especially in the assessment of mild stenosis, and these differences are more important with MRA than with DSA. Differences between the imaging modalities or the reconstruction programs seem less important.
我们的目的是评估使用磁共振血管造影（MRA）评估颈动脉狭窄的最常用方法之间的可重复性及差异。我们研究了55例接受轴向三维时间飞跃MRA（1.5T）检查的患者。根据北美症状性颈动脉内膜切除术试验（NASCET）和欧洲颈动脉外科试验（ECST）的标准，从最大强度投影（MIP）和多平面重建（MPR）图像上进行定量卡尺测量。将测量结果相互比较，并与视觉解读结果进行比较，以传统血管造影作为参考。使用NASCET（平均差异1.9 - 3.0%）和ECST（6.3 - 6.7%）标准时，MRA上测量的狭窄百分比均高于数字减影血管造影（DSA）。DSA与MRA之间一致性的kappa系数，使用NASCET标准（0.61 - 0.76）时高于ECST标准（0.52 - 0.65）。MIP和MPR图像测量结果之间未发现统计学上的显著差异。ECST测量标准得出的狭窄百分比显著高于NASCET标准（P < 0.001），这种差异在MRA上（直径狭窄百分比平均差异14.3 - 16.4%）比在DSA上（7.6 - 11.2%）更明显，且在轻度狭窄时最为重要。MRA上视觉解读与定量测量之间的差异显著（P = 0.01 - 0.001）。在MRA影像判读中，无论是视觉估计的狭窄程度还是狭窄测量，观察者间均未发现统计学上的显著差异。因此，两项多中心试验的不同标准导致了显著不同的结果，尤其是在轻度狭窄的评估中，并且这些差异在MRA中比在DSA中更重要。成像方式或重建程序之间的差异似乎不太重要。
