Raghuram Ashrita, Varon Alberto, Sanchez Sebastian, Ishii Daizo, Wu Chaorong, Magnotta Vincent A, Hasan David M, Koscik Timothy R, Samaniego Edgar A
Department of Neurology, University of Iowa Carver College of Medicine, Iowa City, IA.
Department of Neurosurgery, University of Iowa Carver College of Medicine, Iowa City, IA.
Stroke Vasc Interv Neurol. 2022 Jul;2(4). doi: 10.1161/svin.121.000309. Epub 2022 May 8.
Aneurysm wall enhancement has been identified as a potential biomarker for aneurysm instability. Enhancement has been determined by different approaches on 2D multiplanar views. This study describes a new method to quantify enhancement through 3D heatmaps and histograms.
A custom algorithm was developed using orthogonal probes extending from the aneurysm lumen into the wall to create 3D heatmaps and histograms of wall enhancement on 7T-MRI. Three quantitative metrics for general, specific, and focal wall enhancement were generated from the histograms.
Thirty-two aneurysms were analyzed and classified based on 3D heatmaps and histograms. Larger aneurysms were more enhancing (Spearman's r=0.472, p=0.006), and had more heterogeneous enhancement (Spearman's r=0.557, p<0.001) than smaller aneurysms. Patterns of enhancement differed between saccular, fusiform, and thrombosed aneurysms. Fusiform aneurysms were larger (p=0.015) and had more heterogenous enhancement compared to saccular aneurysms. Fusiform aneurysms had more areas of focal enhancement (p<0.001) and right skewed histograms (p=0.003).
The 3D analysis of aneurysm wall enhancement provides topographic data of the entire aneurysm wall. New metrics developed based on this method showed that large and fusiform aneurysms have heterogenous enhancement.
动脉瘤壁强化已被确定为动脉瘤不稳定性的潜在生物标志物。强化已通过二维多平面视图上的不同方法来确定。本研究描述了一种通过三维热图和直方图量化强化的新方法。
开发了一种定制算法，使用从动脉瘤腔延伸到壁内的正交探头，在7T磁共振成像上创建壁强化的三维热图和直方图。从直方图中生成了用于一般、特定和局灶性壁强化的三个定量指标。
基于三维热图和直方图对32个动脉瘤进行了分析和分类。较大的动脉瘤比较小的动脉瘤强化更明显（斯皮尔曼相关系数r = 0.472，p = 0.006），且强化更不均匀（斯皮尔曼相关系数r = 0.557，p < 0.001）。囊状、梭形和血栓性动脉瘤的强化模式不同。与囊状动脉瘤相比，梭形动脉瘤更大（p = 0.015）且强化更不均匀。梭形动脉瘤有更多的局灶性强化区域（p < 0.001）和右偏态直方图（p = 0.003）。
动脉瘤壁强化的三维分析提供了整个动脉瘤壁的地形数据。基于此方法开发的新指标表明，大型和梭形动脉瘤有不均匀强化。
