背景:前庭神经鞘瘤(VS)的大小是指导最初决定治疗以及肿瘤控制或失败定义的主要因素。准确的测量和标准化的定义是强制性的,但没有标准存在。已经报道了使用线性测量或分段体积的各种近似方法。我们回顾了不同的容量测量方法,并使用我们自己的历史队列评估了它们的相关性和一致性。
方法:我们选择了在我们部门通过伽玛克尼夫放射外科(GKRS)治疗散发性VS的患者。在GKRS当天使用立体定向3DT1增强MRI,4种使用线性测量的容积测量方法(5轴,3轴,3轴平均,和1轴)和分段容量相互比较。使用组内相关性检验(ICC3,1)评估相关性程度。使用Bland-Altman图评估了不同方法之间的一致性。
结果:共纳入2,188例患者。我们观察到5轴容量(0.98)之间有一个很好的ICC,3轴容积测量(0.96),和3轴平均容积(0.96)和分段容积,分别,无论Koos等级或Ohata分类。单轴容量的ICC较低(0.72),并且根据Koos和Ohata亚组的不同而变化。这些方法都不是可替代的。
结论:虽然节段容积法被认为是最准确的方法,与使用线性测量的体积法相比,它需要更多的努力,并且需要复杂的计算系统。在评估的所有方法中,5轴容积法提供了分段容积法的最佳充分性,无论肿瘤的形状如何。不应使用单轴容积法。
The size of vestibular schwannomas (VS) is a major factor guiding the initial decision of treatment and the definition of tumor control or failure. Accurate measurement and standardized definition are mandatory; yet no standard exist. Various approximation methods using linear measures or segmental volumetry have been reported. We reviewed different methods of volumetry and evaluated their correlation and agreement using our own historical cohort.
We selected patients treated for sporadic VS by Gammaknife radiosurgery (GKRS) in our department. Using the stereotactic 3D T1 enhancing MRI on the day of GKRS, 4 methods of volumetry using linear measurements (5-axis, 3-axis, 3-axis-averaged, and 1-axis) and segmental volumetry were compared to each other. The degree of correlation was evaluated using an intraclass correlation test (ICC 3,1). The agreement between the different methods was evaluated using Bland-Altman diagrams.
A total of 2,188 patients were included. We observed an excellent ICC between 5-axis volumetry (0.98), 3-axis volumetry (0.96), and 3-axis-averaged volumetry (0.96) and segmental volumetry, respectively, irrespective of the Koos grade or Ohata classification. The ICC for 1-axis volumetry was lower (0.72) and varied depending on the Koos and Ohata subgroups. None of these methods were substitutable.
Although segmental volumetry is deemed the most accurate method, it takes more effort and requires sophisticated computation systems compared to methods of volumetry using linear measurements. 5-axis volumetry affords the best adequacy with segmental volumetry among all methods under assessment, irrespective of the shape of the tumor. 1-axis volumetry should not be used.