The Ohio State University Veterinary Medical Center, 601 Vernon L. Tharp Street, Columbus, OH, 43221, USA.
BMC Vet Res. 2020 Mar 20;16(1):94. doi: 10.1186/s12917-020-02313-7.
Syringomyelia (SM) is a debilitating condition in the cavalier King Charles spaniel (CKCS) that results in neuropathic pain and diminished quality of life. Von Frey aesthesiometry (VFA) is a method of mechanical quantitative sensory testing that provides an objective sensory threshold (ST) value and can be used to quantify neuropathic pain (NP) and monitor response to therapy. The utility of VFA has been previously established in client-owned dogs with acute spinal cord injury but the technique has not been evaluated in dogs with SM. The goal of this study was to evaluate ST, as determined by VFA, in dogs with and without SM, to assess the utility of VFA in quantifying NP in SM-affected dogs. We hypothesized the SM-affected CKCS would have lower ST values, consistent with hyperesthesia, when compared to control CKCS. Additionally, we hypothesized that ST values in SM-affected dogs would be inversely correlated with syrinx size on MRI and with owner-derived clinical sign scores.
ST values for the thoracic and pelvic limbs differed significantly between the SM-affected and control CKCS (p = 0.027; p = 0.0396 respectively). Median ST value (range) for the thoracic limbs was 184.1 g (120.9-552) for control dogs, and 139.9 g (52.6-250.9) for SM-affected dogs. The median ST value (range) for the pelvic limbs was 164.9 g (100.8-260.3) in control dogs and 129.8 g (57.95-168.4) in SM-affected dogs. The ST values in SM-affected dogs did not correlate with syrinx height on MRI (r = 0.314; p = 0.137). Owner-reported clinical sign scores showed an inverse correlation with pelvic limb ST values, where dogs with lower ST values (hyperesthesia) were reported by their owners to display more frequent and severe clinical signs (r = - 0.657; p = 0.022).
ST values were lower in SM-affected CKCS compared to control dogs, suggesting the presence of neuropathic pain. Dogs with lower ST pelvic limb values were perceived by their owners to have more severe clinical signs classically associated with SM. Our results suggest that VFA might offer quantitative assessment of neuropathic pain in SM-affected dogs and could be useful for monitoring response to therapy in future clinical studies.
硬脊膜下腔空洞症（SM）是一种使可卡犬衰弱的病症，会导致神经性疼痛和生活质量下降。von Frey 触觉测定法（VFA）是一种机械定量感觉测试方法，提供客观的感觉阈值（ST）值，可用于量化神经性疼痛（NP）并监测治疗反应。该技术已在患有急性脊髓损伤的客户拥有的犬中得到了先前的评估，但尚未在患有 SM 的犬中进行评估。本研究的目的是评估 SM 犬和无 SM 犬的 ST 值，以评估 VFA 在量化 SM 犬的 NP 中的效用。我们假设与对照可卡犬相比，患有 SM 的可卡犬的 ST 值会更低，这与感觉过敏一致。此外，我们假设 SM 犬的 ST 值与 MRI 上的脊髓空洞大小以及主人评估的临床症状评分呈负相关。
SM 犬和对照可卡犬的 ST 值在胸腿和骨盆腿之间有显著差异（p=0.027；p=0.0396）。对照组狗的胸腿中位 ST 值（范围）为 184.1g（120.9-552），SM 犬为 139.9g（52.6-250.9）。对照组狗的骨盆腿中位 ST 值（范围）为 164.9g（100.8-260.3），SM 犬为 129.8g（57.95-168.4）。SM 犬的 ST 值与 MRI 上的脊髓空洞高度无关（r=0.314；p=0.137）。主人报告的临床症状评分与骨盆腿 ST 值呈负相关，其中 ST 值较低（感觉过敏）的狗被其主人报告显示出更频繁和更严重的临床症状（r=-0.657；p=0.022）。
与对照犬相比，SM 犬的 ST 值较低，表明存在神经性疼痛。ST 骨盆腿值较低的犬被其主人认为具有与 SM 相关的更严重的临床症状。我们的结果表明，VFA 可能为 SM 犬的神经性疼痛提供定量评估，并可用于未来临床研究中监测治疗反应。
