Kishimoto Tomoyuki, Ishida Fujimaro, Tsuji Masanori, Sato Takenori, Furukawa Kazuhiro, Kuroda Yusuke, Ikezawa Munenari, Yamamoto Yoko, Fukazawa Keiji, Suzuki Hidenori
Department of Neurosurgery, Mie Chuo Medical Center, National Hospital Organization.
Department of Neurosurgery, Mie University Graduate School of Medicine.
Neurol Med Chir (Tokyo). 2025 Jul 15;65(7):326-332. doi: 10.2176/jns-nmc.2024-0303. Epub 2025 May 29.
Shape indices such as size ratio are valuable for diagnosing aneurysm rupture status and may influence rupture risk. However, as these indices are calculated based on two-dimensional measurements, bias may arise from observation directions. To address this, we developed a novel parameter, spatial projection ratio, utilizing three-dimensional geometry. A retrospective analysis of 225 aneurysms diagnosed using three-dimensional computed tomography angiography was conducted to evaluate primary variables and spatial projection ratio.Spatial projection ratio is determined by defining the gravity point as the neck orifice center and identifying the furthest point from it using commercial software. The distance between these points, known as spatial projection length, is measured and divided by the equivalent neck diameter to calculate spatial projection ratio. Significant differences in morphological variables for rupture status were observed by Brunner-Munzel tests.Receiver-operating characteristic curve analysis was employed to assess diagnostic accuracy, with Spearman's rank correlation utilized to explore the potential for predicting rupture risk by correlating spatial projection ratio and size ratio. Ruptured aneurysms exhibited significantly higher primary variables and shape indices compared to unruptured ones. The area under receiver-operating characteristic curves of all shape indices surpassed that of primary variables, with spatial projection ratio demonstrating a particularly high area under receiver-operating characteristic curves of 0.791 (95% confidence interval 0.732-0.849; sensitivity, 0.770; specificity, 0.741; cut-off value, 1.047). Moreover, spatial projection ratio exhibited a significant correlation with size ratio (r = 0.575, p < 0.01).Thus, spatial projection ratio emerges as a robust morphological parameter for evaluating rupture status and may provide insights into aneurysm rupture risks.
诸如尺寸比之类的形状指数对于诊断动脉瘤破裂状态很有价值，并且可能影响破裂风险。然而，由于这些指数是基于二维测量计算得出的，观察方向可能会导致偏差。为了解决这个问题，我们利用三维几何开发了一个新的参数——空间投影比。我们对225个使用三维计算机断层血管造影诊断的动脉瘤进行了回顾性分析，以评估主要变量和空间投影比。空间投影比是通过将重心点定义为颈部开口中心，并使用商业软件确定离它最远的点来确定的。测量这两点之间的距离，即空间投影长度，并除以等效颈部直径以计算空间投影比。通过Brunner-Munzel检验观察到破裂状态的形态学变量存在显著差异。采用受试者工作特征曲线分析来评估诊断准确性，利用Spearman等级相关性通过关联空间投影比和尺寸比来探索预测破裂风险的可能性。与未破裂的动脉瘤相比，破裂的动脉瘤表现出显著更高的主要变量和形状指数。所有形状指数的受试者工作特征曲线下面积均超过主要变量，空间投影比的受试者工作特征曲线下面积特别高，为0.791（95%置信区间0.732 - 0.849；灵敏度，0.770；特异性，0.741；临界值，1.047）。此外，空间投影比与尺寸比呈现显著相关性（r = 0.575，p < 0.01）。因此，空间投影比成为评估破裂状态的一个可靠形态学参数，并可能为动脉瘤破裂风险提供见解。
