Beckett Joel S, Lagman Carlito, Chung Lawrance K, Bui Timothy T, Lee Seung J, Voth Brittany L, Gaonkar Bilwaj, Gopen Quinton, Yang Isaac
Department of Neurosurgery, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, California, United States.
Department of Head and Neck Surgery, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, California, United States.
J Neurol Surg B Skull Base. 2017 Apr;78(2):197-200. doi: 10.1055/s-0036-1594241. Epub 2016 Dec 7.
Superior semicircular canal dehiscence (SSCD) describes a pathological aperture at the level of the arcuate eminence. Techniques for quantifying defect size are described with most studies using two-dimensional lengths that underestimate the pathology. The objective of this study is to describe a novel method of measurement that combines manual segmentation of high-resolution computed tomography (HRCT) images of the temporal bone and a morphological skeletonization transform to calculate dehiscence volume. Images were imported into a freely available image segmentation tool: ITK-SNAP (version 3.4.0; available at: http://www.itksnap.org/) software. Coronal and sagittal planes were used to outline the dehiscence in all slices demonstrating the defect using the paintbrush tool. A morphological skeletonization transform derived a single-pixel thick representation of the original delineation. This "sheet" of voxels overlaid the dehiscence. Volume was calculated by counting the number of nonzero image voxels within this "sheet" and multiplying this number by the volume (mm) of each voxel. A total of 70 cases of SSCD were identified. Overall, mean volume was 0.88 mm (standard deviation: 0.57, range: 0.11-2.27). We present a novel technique for measuring SSCD, which we believe provides a more accurate representation of the pathology, and has the potential to standardize measurement of SSCD.
上半规管裂（SSCD）是指在弓状隆起水平处的病理性开口。已有研究描述了量化缺损大小的技术，但大多数研究使用的二维长度会低估病变情况。本研究的目的是描述一种新的测量方法，该方法结合了颞骨高分辨率计算机断层扫描（HRCT）图像的手动分割和形态学骨架化变换来计算裂孔体积。图像被导入到一个免费的图像分割工具：ITK-SNAP（版本3.4.0；可从http://www.itksnap.org/获取）软件中。使用画笔工具，在所有显示缺损的切片上，通过冠状面和矢状面勾勒出裂孔。形态学骨架化变换得到了原始轮廓的单像素厚表示。这个“薄片”状的体素覆盖在裂孔上。通过计算这个“薄片”内非零图像体素的数量，并将该数量乘以每个体素的体积（立方毫米）来计算体积。共识别出70例SSCD病例。总体而言，平均体积为0.88立方毫米（标准差：0.57，范围：0.11 - 2.27）。我们提出了一种测量SSCD的新技术，我们认为该技术能更准确地反映病变情况，并且有可能使SSCD的测量标准化。
