Kleinloog Rachel, Korkmaz Emine, Zwanenburg Jaco J M, Kuijf Hugo J, Visser Fredy, Blankena Roos, Post Jan A, Ruigrok Ynte M, Luijten Peter R, Regli Luca, Rinkel Gabriel J E, Verweij Bon H
*Department of Neurology and Neurosurgery, Brain Center Rudolf Magnus, §Image Sciences Institute, and ¶Department of Radiology, University Medical Center Utrecht, Utrecht, the Netherlands; ‡Biomolecular Imaging, Department of Biology, Science Faculty, Utrecht University, Utrecht, the Netherlands; ‖Philips Healthcare, Best, the Netherlands; #Faculty of Science and Technology, Department of Technical Medicine, University of Twente, Enschede, the Netherlands; **Department of Neurosurgery, University Hospital Zurich, Zurich, Switzerland.
Neurosurgery. 2014 Dec;75(6):614-22; discussion 622. doi: 10.1227/NEU.0000000000000559.
Risk prediction of rupture of intracranial aneurysms is poor and is based mainly on lumen characteristics. However, characteristics of the aneurysm wall may be more informative predictors. The limited resolution of currently available imaging techniques and the thin aneurysm wall make imaging of wall thickness challenging.
To introduce a novel protocol for imaging wall thickness variation using ultra--high-resolution 7.0-Tesla (7.0-T) magnetic resonance imaging (MRI).
We studied 33 unruptured intracranial aneurysms in 24 patients with a T1-weighted 3-dimensional magnetization-prepared inversion-recovery turbo-spin-echo whole-brain sequence with a resolution of 0.8 × 0.8 × 0.8 mm. We performed a validation study with a wedge phantom and with 2 aneurysm wall biopsies obtained during aneurysm treatment using ex vivo MRI and histological examination and correlating variations in MRI signal intensity with variations in actual thickness of the aneurysm wall.
In vivo, the aneurysm wall was visible in 28 of the 33 aneurysms. Variation in signal intensity was observed in all visible aneurysm walls. Ex vivo MRI showed variation in signal intensity across the wall of the biopsies, similar to that observed on the in vivo images. Signal intensity and actual thickness in both biopsies had a linear correlation, with Pearson correlation coefficients of 0.85 and 0.86.
Unruptured intracranial aneurysm wall and its variation in thickness can be visualized with 7.0-T MRI. Aneurysm wall thickness variation can now be further studied as a risk factor for rupture in prospective studies.
颅内动脉瘤破裂的风险预测效果不佳，主要基于管腔特征。然而，动脉瘤壁的特征可能是更具信息量的预测指标。当前可用成像技术的分辨率有限以及动脉瘤壁较薄，使得对壁厚度进行成像具有挑战性。
介绍一种使用超高分辨率7.0特斯拉（7.0-T）磁共振成像（MRI）对壁厚度变化进行成像的新方案。
我们对24例患者的33个未破裂颅内动脉瘤进行了研究，采用分辨率为0.8×0.8×0.8毫米的T1加权三维磁化准备快速反转恢复涡轮自旋回波全脑序列。我们使用楔形模型以及在动脉瘤治疗期间获得的2份动脉瘤壁活检组织进行了验证研究，通过离体MRI和组织学检查，并将MRI信号强度的变化与动脉瘤壁实际厚度的变化相关联。
在体情况下，33个动脉瘤中有28个可见动脉瘤壁。在所有可见的动脉瘤壁中均观察到信号强度变化。离体MRI显示活检组织壁上的信号强度变化，类似于在体图像上观察到的情况。两份活检组织中的信号强度与实际厚度均呈线性相关，皮尔逊相关系数分别为0.85和0.86。
7.0-T MRI可显示未破裂颅内动脉瘤壁及其厚度变化。现在可以在前瞻性研究中将动脉瘤壁厚度变化作为破裂的危险因素进行进一步研究。
