Bilston L E, Fletcher D F, Stoodley M A
Prince of Wales Medical Research Institute, University of New South Wales, Barker Street, Randwick, NSW 2031, Australia.
Clin Biomech (Bristol). 2006 Jul;21(6):579-84. doi: 10.1016/j.clinbiomech.2006.01.009. Epub 2006 Mar 13.
Enlarging fluid filled cystic cavitations form within the spinal cord in up to 28% of spinal cord injured patients. These post-traumatic syrinxes can cause neurological deterioration and current treatment results are unsatisfactory. Localized scar tissue (arachnoiditis) within the subarachnoid space at the level of injury has been suggested to be involved in the pathogenesis of syrinx formation. This study tests the hypothesis that pressure pulses in the subarachnoid space are accentuated adjacent to regions of arachnoiditis, which may drive fluid into the spinal cord and contribute to syrinx formation.
An axisymmetric, cylindrical computational fluid dynamics model was developed to represent the subarachnoid space under normal physiological conditions and in the presence of arachnoiditis. Cerebrospinal fluid flow into the model was estimated from magnetic resonance imaging flow studies. Arachnoiditis was modelled as a porous obstruction in the subarachnoid space.
Peak fluid pressures were higher above the obstruction than in the absence of obstruction. The peak pressures were strongly dependent on the permeability of the obstruction.
Elevations in subarachnoid space pressures due to arachnoiditis may facilitate fluid flow into the spinal cord, enhancing syrinx formation. This suggests that it may be worthwhile to investigate strategies that inhibit arachnoiditis or minimize systolic pressure peaks for treating or preventing syringomyelia.
在高达28%的脊髓损伤患者中，脊髓内会形成不断扩大的充满液体的囊性空洞。这些创伤后脊髓空洞可导致神经功能恶化，目前的治疗效果并不理想。有研究表明，损伤水平的蛛网膜下腔内局部瘢痕组织（蛛网膜炎）参与了脊髓空洞形成的发病机制。本研究检验了以下假设：蛛网膜下腔内的压力脉冲在蛛网膜炎区域附近会增强，这可能会驱使液体进入脊髓并导致脊髓空洞形成。
建立了一个轴对称的圆柱形计算流体动力学模型，以代表正常生理条件下和存在蛛网膜炎时的蛛网膜下腔。根据磁共振成像血流研究估算进入模型的脑脊液流量。将蛛网膜炎模拟为蛛网膜下腔内的多孔阻塞。
阻塞上方的流体峰值压力高于无阻塞时。峰值压力强烈依赖于阻塞的渗透率。
蛛网膜炎导致的蛛网膜下腔压力升高可能会促进液体流入脊髓，增强脊髓空洞的形成。这表明，研究抑制蛛网膜炎或使收缩压峰值最小化的策略来治疗或预防脊髓空洞症可能是值得的。
