Center for Advanced Orthopedic Studies, Department of Orthopedic Surgery, Beth Israel Deaconess Medical Center, Boston, MA, United States of America; Harvard Medical School, Boston, MA, United States of America.
Harvard Dental School, Boston, MA, United States of America.
Bone. 2024 Jan;178:116923. doi: 10.1016/j.bone.2023.116923. Epub 2023 Sep 29.
Several new peripheral dual-energy X-ray absorptiometry (DXA) devices designed for assessment of bone and body composition in rodents have been developed. We compared the performance (accuracy and precision) of two of these devices, the InAlyzer and the iNSiGHT, to those of an established device, the PIXImus. We measured total body bone mineral content (BMC), bone mineral density (BMD), and body composition (lean and fat mass) on the three DXA devices in 18 male C57Bl/6 J mice (6 each of ages 8, 14, and 24 weeks, weighing 22 to 33 g). DXA body composition measures were compared to whole-body nuclear magnetic resonance (NMR) outcomes. BMC of the femur was also compared to ex vivo micro-computed tomography (microCT). Total body BMD from the InAlyzer and iNSiGHT devices was strongly correlated to that from PIXImus (R = 0.83 and 0.82, respectively), but was ~25 % higher than PIXImus. Total body BMC measures by InAlyzer were strongly associated with those from PIXImus (R = 0.86), whereas those from iNSiGHT were only weakly correlated (R = 0.29). Femur BMC from InAlyzer was strongly correlated with microCT outcomes, whereas iNSiGHT was only weakly correlated. InAlyzer and iNSiGHT fat mass measures were very strongly correlated with PIXImus and NMR outcomes (R = 0.91 to 0.97), with slightly weaker associations for lean mass (R = 0.81 to 0.76). Short-term precision of InAlyzer and iNSiGHT measurements were excellent, and akin to those from the PIXImus for both body composition and bone measures, ranging between 0.39 and 3.2 %. With faster scan times, closed X-ray source and excellent precision, the new devices are both satisfactory replacements for the now discontinued PIXImus system. However, given the accuracy of the bone and body composition measures, the InAlyzer may be preferable for studies where musculoskeletal changes are the main interest.
已经开发出几种新的外周双能 X 射线吸收测定法（DXA）设备，用于评估啮齿动物的骨骼和身体成分。我们比较了两种设备，即 InAlyzer 和 iNSiGHT，以及一种已建立的设备 PIXImus 的性能（准确性和精密度）。我们在三种 DXA 设备上测量了 18 只雄性 C57Bl/6J 小鼠（8、14 和 24 周龄各 6 只，体重 22 至 33 克）的全身骨矿物质含量（BMC）、骨矿物质密度（BMD）和身体成分（瘦体重和脂肪量）。DXA 身体成分测量结果与全身磁共振（NMR）结果进行了比较。股骨 BMC 也与离体微计算机断层扫描（microCT）进行了比较。InAlyzer 和 iNSiGHT 设备的全身 BMD 与 PIXImus 高度相关（分别为 R=0.83 和 0.82），但比 PIXImus 高约 25%。InAlyzer 的全身 BMC 测量值与 PIXImus 高度相关（R=0.86），而 iNSiGHT 的相关性较弱（R=0.29）。InAlyzer 的股骨 BMC 与 microCT 结果高度相关，而 iNSiGHT 仅弱相关。InAlyzer 和 iNSiGHT 的脂肪量测量值与 PIXImus 和 NMR 结果非常密切相关（R=0.91 至 0.97），与瘦体重的关联稍弱（R=0.81 至 0.76）。InAlyzer 和 iNSiGHT 测量的短期精密度非常好，与 PIXImus 相比，身体成分和骨骼测量的精密度均相同，范围在 0.39 至 3.2%之间。由于扫描时间更快、封闭的 X 射线源和出色的精密度，新设备都是现已停产的 PIXImus 系统的理想替代品。然而，鉴于骨骼和身体成分测量的准确性，对于主要关注肌肉骨骼变化的研究，InAlyzer 可能更可取。
