Al-Habib Amro, Albakr Abdulrahman, Al Towim Abdullah, Alkubeyyer Metab, Abu Jamea Abdullah, Albadr Fahad, Eldawlatly Abdelazeem A, Kashour Tarek, Alkhalidi Hisham, Alzahrani Tariq
1Division of Neurosurgery, Department of Surgery, and.
Departments of2Radiology.
J Neurosurg Spine. 2018 Oct;29(4):461-469. doi: 10.3171/2018.2.SPINE171195. Epub 2018 Jul 20.
Evaluation of living tissue elasticity has wide applications in disease characterization and prognosis prediction. Few previous ex vivo attempts have been made to characterize spinal cord elasticity (SCE). Recently, tissue elasticity assessment has been clinically feasible using ultrasound shear wave elastography (SWE). The current study aims to characterize SCE in healthy dogs, in vivo, utilizing SWE, and to address SCE changes during compression.
Ten Greyhound dogs (mean age 14 months; mean weight 14.3 kg) were anesthetized and tracheally intubated, with hemodynamic and neurological monitoring. A 3-level, midcervical laminectomy was performed. SCE was assessed at baseline. Next, 8- and 13-mm balloon compressions were sequentially applied ventral to the spinal cord.
The mean SCE was 18.5 ± 7 kPa. Elasticity of the central canal, pia mater, and dura mater were 21.7 ± 9.6 kPa, 26.1 ± 14.8 kPa, and 63.2 ± 11.5 kPa, respectively. As expected, the spinal cord demonstrated less elasticity than the dura mater (p < 0.0001) and pia mater (trend toward significance p = 0.08). Notably, the 13-mm balloon compression resulted in a stiffer spinal cord than at baseline (233 ± 73 kPa versus 18.5 ± 7 kPa, p < 0.0001) and 8-mm balloon compression (233 ± 73 kPa versus 185 ± 68 kPa, p < 0.048).
In vivo SCE evaluation using SWE is feasible and comparable to earlier reports, as demonstrated by physical sectioning of the spinal cord. The compressed spinal cord is stiffer than a free spinal cord, with a linear increase in SCE with increasing mechanical compression. Knowledge of the biomechanical properties of the spinal cord including SCE has potential implications for disease management and prognosis.
评估活体组织弹性在疾病特征描述和预后预测方面有广泛应用。此前很少有体外研究尝试对脊髓弹性（SCE）进行特征描述。最近，使用超声剪切波弹性成像（SWE）进行组织弹性评估在临床上已可行。本研究旨在利用SWE在活体健康犬体内对SCE进行特征描述，并探讨压缩过程中SCE的变化。
对10只灵缇犬（平均年龄14个月；平均体重14.3千克）进行麻醉并气管插管，同时进行血流动力学和神经学监测。实施三级颈椎中段椎板切除术。在基线时评估SCE。接下来，在脊髓腹侧依次施加8毫米和13毫米的球囊压迫。
平均SCE为18.5±7千帕。中央管、软脑膜和硬脑膜的弹性分别为21.7±9.6千帕、26.1±14.8千帕和63.2±11.5千帕。正如预期的那样，脊髓的弹性低于硬脑膜（p<0.0001）和软脑膜（有显著趋势，p=0.08）。值得注意的是，13毫米球囊压迫导致脊髓比基线时更硬（233±73千帕对18.5±7千帕，p<0.0001），也比8毫米球囊压迫时更硬（233±73千帕对185±68千帕，p<0.048）。
使用SWE进行体内SCE评估是可行的，并且与早期报告结果相当，脊髓的物理切片已证明了这一点。受压脊髓比未受压脊髓更硬，随着机械压迫增加，SCE呈线性增加。了解包括SCE在内的脊髓生物力学特性对疾病管理和预后具有潜在意义。
