Mallinckrodt Institute of Radiology, Washington University School of Medicine, St. Louis, MO 63110, USA.
J Digit Imaging. 2009 Oct;22(5):492-502. doi: 10.1007/s10278-008-9118-z. Epub 2008 May 14.
A new method for measuring bone mineral density (BMD) of the tarsal and metatarsals is described using volumetric quantitative computed tomography (VQCT) in subjects with diabetes mellitus and peripheral neuropathy. VQCT images of a single foot were acquired twice from eight subjects (mean age 51 [11 SD], seven males, one female). The cortical shells of the seven tarsal and five metatarsal bones were identified and semiautomatically segmented from adjacent bones. Volume and BMD of each bone were measured separately from the two acquired scans for each subject. Whole-bone semiautomatic segmentation measurement errors were determined as the root mean square coefficient of variation for the volume and BMD of 0.8% and 0.9%, respectively. In addition to the whole-bone segmentation methods, we performed atlas-based partitioning of subregions within the second metatarsal for all subjects, from which the volumes and BMDs were obtained for each subregion. The subregion measurement BMD errors (root mean square coefficient of variation) within the shaft, proximal end, and distal end were shown to vary by approximately 1% between the two scans of each subject. The new methods demonstrated large variations in BMDs between the 12 bones of the foot within a subject and between subjects, and between subregions within the second metatarsal. These methods can provide an important outcome measure for clinical research trials investigating the effects of interventions, aging, or disease progression on bone loss, or gain, in individual foot bones.
一种新的测量糖尿病伴周围神经病变患者跗骨和跖骨骨密度（BMD）的方法是使用容积定量 CT（VQCT）。从 8 名受试者（平均年龄 51 [11 标准差]，7 名男性，1 名女性）的一只脚采集了两次 VQCT 图像。从相邻骨骼中识别并半自动分割出 7 个跗骨和 5 个跖骨的皮质壳。从两次扫描中分别测量每个受试者的每个骨骼的体积和 BMD。整个骨骼半自动分割测量误差分别为体积和 BMD 的均方根变异系数的 0.8%和 0.9%。除了全骨分割方法外，我们还对所有受试者的第二跖骨进行了基于图谱的分区，从每个分区获得了体积和 BMD。结果显示，每个受试者的两次扫描之间，骨干、近端和远端的亚区测量 BMD 误差（均方根变异系数）变化约为 1%。新方法在受试者的 12 个足部骨骼之间以及不同受试者之间的 BMD 差异较大，并且在第二跖骨的亚区之间也存在较大差异。这些方法可以为临床研究试验提供重要的结果衡量标准，这些试验旨在研究干预、衰老或疾病进展对个体足部骨骼的骨丢失或增加的影响。
