Aneurysm wall thickness measurements of experimental aneurysms: in vivo high-field MR imaging versus direct microscopy.
Aneurysm wall thickness measurements of experimental aneurysms: in vivo high-field MR imaging versus direct microscopy.
复制标题
DOI：
10.1007/978-3-319-04981-6_3
复制
发表时间：
2015-01-01
期刊：
影响因子：
--
通讯作者：
Krssak, Martin
中科院分区：
文献类型：
--
作者：
Sherif, Camillo;Kleinpeter, Gunther;Krssak, Martin
背景：脑动脉瘤壁厚薄(AWT)与高动脉瘤破裂风险有关。AWT的MR成像会导致高估。本研究的目的是通过与精确的光学显微镜测量相比较来量化MR的不准确性。方法：在13个实验性的兔显微外科分叉部动脉瘤中，采用对比增强的T1 Flash序列(分辨率：0.4*0.4*1.5 mm)进行3Tesla(3T)-MR成像。在MR采集后立即取回动脉瘤，进行纵向切割，并获得校准的照片。由独立调查者在MR图像和显微镜照片上测量AWT(穹顶、颈部)和载瘤血管厚度(PVT)。结果：所有动脉瘤均能较好地显示和测量AWT和PVT。与“真实”光镜测量相比，AWT随AWT变小而逐渐增加：圆顶AWT(0.24±0.06 mm vs MR 0.30±0.08 mm；p=0.0078；R=0.6125)，颈部AWT(0.25±0.07 mm vs MR 0.29±0.07 mm；P=0.0469；R=0.7451)，PVT(0.46±0.06 mm vs MR 0.48±0.06 mm；p=0.50；R=0.8568)。结论：在本实验设置中，大脑AWT的3T-MR成像仅在图像分辨率阈值以下显示不可接受的不准确性。从理论上讲，临床使用的AWT可以按最大图像分辨率定义的范围进行分类。
BACKGROUND: Thin cerebral aneurysm wall thickness (AWT) is connected to high aneurysm rupture risk. MR imaging of AWT leads to overestimations. The aim of the present study was to quantify MR inaccuracy by comparison with accurate light microscopic measurements.METHODS: In 13 experimental microsurgical bifurcation aneurysms in rabbits, 3 Tesla (3 T)-MR imaging using contrast-enhanced T1 Flash sequences (resolution: 0.4 * 0.4 * 1.5 mm) was performed. The aneurysms were retrieved immediately after MR acquisition, cut longitudinally, and calibrated photographs were obtained. AWT (dome, neck) and parent vessel thickness (PVT) were measured on the MR images and microscopic photographs by independent investigators. All parameters were statistically compared (Wilcoxon test, Spearman correlation).RESULTS: AWT and PVT could be imaged and measured in all aneurysms with good quality. Comparison with the "real" light microscopic measurements showed a progressive tendency of MR AWT overestimation with smaller AWT: AWT at the dome (0.24 ± 0.06 mm vs. MR 0.30 ± 0.08 mm; p = 0.0078; R = 0.6125), AWT at the neck (0.25 ± 0.07 mm vs. MR 0.29 ± 0.07 mm; p = 0.0469; R = 0.7451), and PVT (0.46 ± 0.06 mm vs. MR 0.48 ± 0.06 mm; p = 0.5; R = 0.8568).CONCLUSION: In this experimental setting, 3 T-MR imaging of cerebral AWT showed unacceptable inaccuracies only below the image resolution threshold. Theoretically, AWT for clinical usage could be classified in ranges, defined by the maximum image resolution.