Pillar of Engineering Product Development, Singapore University of Technology and Design, Singapore, Singapore.
Department of Neuroradiology, Klinikum rechts der Isar, Technical University of Munich, Munich, Germany.
J Bone Miner Metab. 2018 May;36(3):323-335. doi: 10.1007/s00774-017-0836-5. Epub 2017 Apr 7.
Osteoporosis is characterized by bone loss and degradation of bone microstructure leading to fracture particularly in elderly people. Osteoporotic bone degeneration and fracture risk can be assessed by bone mineral density and trabecular bone score from 2D projection dual-energy X-ray absorptiometry images. However, multidetector computed tomography image based quantification of trabecular bone microstructure showed significant improvement in prediction of fracture risk beyond that from bone mineral density and trabecular bone score; however, high radiation exposure limits its use in routine clinical in vivo examinations. Hence, this study investigated reduction of radiation dose and its effects on image quality of thoracic midvertebral specimens. Twenty-four texture features were extracted to quantify the image quality from multidetector computed tomography images of 11 thoracic midvertebral specimens, by means of statistical moments, the gray-level co-occurrence matrix, and the gray-level run-length matrix, and were analyzed by an independent sample t-test to observe differences in image texture with respect to radiation doses of 80, 150, 220, and 500 mAs. The results showed that three features-namely, global variance, energy, and run percentage, were not statistically significant ([Formula: see text]) for low doses with respect to 500 mAs. Hence, it is evident that these three dose-independent features can be used for disease monitoring with a low-dose imaging protocol.
骨质疏松症的特征是骨丢失和骨微观结构的退化，导致骨折，特别是在老年人中。通过二维投影双能 X 射线吸收法图像的骨矿物质密度和小梁骨评分，可以评估骨质疏松性骨退变和骨折风险。然而，基于多排 CT 图像的小梁骨微观结构定量分析显示，在预测骨折风险方面，除了骨矿物质密度和小梁骨评分之外，有显著改善；然而，高辐射暴露限制了其在常规临床体内检查中的应用。因此，本研究调查了减少辐射剂量及其对胸腰椎标本图像质量的影响。从 11 个胸腰椎标本的多排 CT 图像中提取了 24 个纹理特征，通过统计矩、灰度共生矩阵和灰度游程长度矩阵来量化图像质量，并通过独立样本 t 检验分析，观察图像纹理随 80、150、220 和 500 mAs 辐射剂量的差异。结果表明，对于低剂量，三个特征——全局方差、能量和游程百分比，与 500 mAs 相比没有统计学意义（[公式：见正文]）。因此，显然这三个与剂量无关的特征可以用于低剂量成像方案的疾病监测。
