Department of Orthopaedics, Osaka University Graduate School of Medicine, Suita, Osaka, Japan.
Division of Information Science, Graduate School of Science and Technology, Nara Institute of Science and Technology, Ikoma, Nara, Japan.
Calcif Tissue Int. 2022 Nov;111(5):475-484. doi: 10.1007/s00223-022-01012-9. Epub 2022 Jul 29.
While accurate measurement of bone mineral density (BMD) is essential in the diagnosis of osteoporosis and in evaluating the treatment of osteoporosis, it is unclear how region of interest (ROI) settings affect measurement of BMD at the total proximal femur region. In this study, we performed a simulation analysis to clarify the effect on BMD measurement of changing the ROI using hip computed tomography (CT) images of 75 females (mean age, 62.4 years). Digitally reconstructed radiographs of the proximal femur region were generated from CT images to calculate the change in BMD when the proximal boundary of the ROI was altered by 0-10 mm, and when the distal boundary of the ROI was altered by 0-30 mm. Further, changes in BMD were compared across BMD classification groups. A mean BMD increase of 0.62% was found for each 1-mm extension of the distal boundary. A mean BMD decrease of 0.18% was found for each 1-mm alteration of the proximal boundary. Comparing BMD classification groups, patients with osteoporosis and osteopenia demonstrated greater BMD changes than patients with normal BMD for the distal boundary (0.68%, 0.64%, and 0.54%, respectively) and patients with osteoporosis demonstrated greater BMD changes than patients with osteoporosis and normal BMD for the proximal boundary (0.37%, 0.13%, and 0.03%, respectively). In conclusion, our study found that a consistent ROI setting, especially on the distal boundary, is necessary for the accurate measurement of total proximal femur BMD. Based on the findings, we recommend confirming that the ROI setting shown on the BMD result form is consistent with changes in serial BMD.
虽然骨密度（BMD）的精确测量对于骨质疏松症的诊断和评估骨质疏松症的治疗至关重要，但尚不清楚感兴趣区域（ROI）的设置如何影响总股骨近端区域的 BMD 测量。在这项研究中，我们进行了模拟分析，以明确使用 75 名女性（平均年龄 62.4 岁）的髋部 CT（CT）图像改变 ROI 对 BMD 测量的影响。从 CT 图像生成股骨近端区域的数字重建射线照片，以计算当 ROI 的近端边界改变 0-10mm 时和 ROI 的远端边界改变 0-30mm 时 BMD 的变化。此外，比较了不同 BMD 分类组之间的 BMD 变化。发现 ROI 远端边界每延伸 1mm，BMD 增加 0.62%。发现 ROI 近端边界每改变 1mm，BMD 减少 0.18%。比较 BMD 分类组，与正常 BMD 相比，骨质疏松症和骨质减少症患者的 BMD 变化更大，对于远端边界分别为 0.68%、0.64%和 0.54%，而对于近端边界，骨质疏松症患者的 BMD 变化大于骨质疏松症和正常 BMD 患者，分别为 0.37%、0.13%和 0.03%。总之，我们的研究发现，对于准确测量总股骨近端 BMD，需要有一致的 ROI 设置，特别是在远端边界。基于这些发现，我们建议确认 BMD 结果表单上显示的 ROI 设置与连续 BMD 的变化一致。
