Department of Clinical Sciences, Orthopaedic Research Center, C. Wayne McIlwraith Translational Medicine Institute, College of Veterinary Medicine and Biomedical Sciences, Colorado State University, Fort Collins, Colorado, USA.
Animal Imaging, Irving, Texas, USA.
Vet Radiol Ultrasound. 2022 Jan;63(1):111-123. doi: 10.1111/vru.13026. Epub 2021 Sep 28.
Elastography is an emerging imaging modality for characterizing tendon injury in horses, but its ability to differentiate tissue deformability relative to treatment group and biochemical properties using a prospective, experimental study design remain unknown. Objectives of the current study were to (a) to investigate differences in glycosaminoglycan, DNA, and soluble collagen levels in mesenchymal stem cell (MSC) treated limbs compared to untreated control limbs utilizing a collagenase model of tendinopathy; (b) compare elastographic features between treatment groups; and (c) determine tissue-level predictive capabilities of elastography in relation to biochemical outcomes. Bone marrow was collected for MSC culture and expansion. Tendinopathy of both forelimb deep digital flexor tendons (DDFTs) was induced with collagenase under ultrasonographic guidance. One randomly assigned limb was treated with intra-lesional MSC injection with the opposite limb serving as an untreated control. Horses were placed into a controlled exercise program with elastographic evaluations performed baseline (0) and 14, 60, 90, and 214 days post-treatment. Postmortem biochemical analysis was performed. MSC-treated limbs demonstrated significantly less (42%) glycosaminoglycan (P = .006). Significant differences in elastographic region of interest (ROI) percent hardness, ROI color histogram, and subjective lesion stiffness were appreciated between treatment groups at various study time points. Elastographic outcome parameters were weak predictors of biochemical tissue analysis, with all R values ≤ 0.50. Within this range of differences in glycosaminoglycan content between treatment groups, elastography outcomes did not predict biochemical differences. Tissue-specific differences between DDFTs treated with MSCs compared to controls were apparent biochemically, but not predicted by elastography.
弹性成像是一种新兴的成像方式，可用于描述马的肌腱损伤，但在使用前瞻性、实验性研究设计来区分组织变形能力与治疗组和生化特性方面的能力尚不清楚。本研究的目的是：(a)利用胶原酶性腱病模型，研究间充质干细胞（MSC）治疗肢体与未治疗对照肢体之间糖胺聚糖、DNA 和可溶性胶原蛋白水平的差异；(b)比较治疗组之间的弹性成像特征；(c)确定弹性成像与生化结果的相关性在组织水平上的预测能力。收集骨髓进行 MSC 培养和扩增。在超声引导下，对双侧前肢深指屈肌腱（DDFT）进行胶原酶诱导性腱病。随机选择一条肢体进行病变内 MSC 注射治疗，对侧肢体作为未治疗对照。在受控运动方案中，对马进行弹性评估，基线（0）和治疗后 14、60、90 和 214 天进行评估。进行死后生化分析。MSC 治疗的肢体的糖胺聚糖（GAG）含量明显减少（42%，P =.006）。在不同的研究时间点，治疗组之间的弹性成像感兴趣区（ROI）硬度百分比、ROI 颜色直方图和主观病变硬度的差异具有统计学意义。弹性成像结果参数是生化组织分析的弱预测因子，所有 R 值均≤0.50。在治疗组之间 GAG 含量差异的范围内，弹性成像结果并不能预测生化差异。与对照组相比，MSC 治疗的 DDFT 在生化上存在组织特异性差异，但不能通过弹性成像预测。
