动态负荷下前列腺素E_1对受压马尾神经血流量变化的影响

目的 :研究动态负荷下前列腺素E1对受压马尾神经血流量变化的影响。方法 :分 4组 ,每组 6只。除对照组 ,其他 3个实验组制成 3 0 %的双节段狭窄。施加压迫 2h后 ,3个实验组分别施加动态负荷 (高频率刺激和 (或 )压迫追加 ) 6min。实验 3组在施加动态负荷前给予前列腺素E1。结果 :对照组马尾神经血流量在最初 2h无显著变化 ,施加高频率刺激时显著升高至 ( 186.4 -3 1.5 ) % (P <0 .0 5 )。施加动态负荷时 ,实验 1组血流无显著变化 (P >0 .0 5 ) ;实验 2组降至 ( 65 .3 -10 .7) % (P <0 .0 5 ) ;实验 3组为 ( 118.5 -2 3 .6) % ,与实验 2组有显著差异 (P <0 .0 5 )。结论 :双节段压迫会限制马尾神经血流量增加而造成相对缺血。若神经电活动与压迫程度同时增加 ,血流量显著降低 ,造成绝对缺血。前列腺素E1可以在动态负荷下维持马尾神经血流量 ,避免其进入绝对缺血状态。     

The effect of Lipo prostaglandin E1 on cauda equina blood flow in patients with lumbar spinal canal stenosis: myeloscopic observation.

STUDY DESIGN: Myeloscopic examination was performed to observe the cauda equina in patients with lumbar spinal canal stenosis before and after treatment with Lipo prostaglandin E1, a strong peripheral vasodilator. OBJECTIVES: The purpose of this study was to clarify the effects of Lipo prostaglandin E1 on blood flow in the cauda equina in patients with lumbar spinal canal stenosis. SETTING: Japan, Kagoshima METHODS: We performed myeloscopic observations of morphological changes in blood vessels running along the cauda equina in 11 patients with lumbar spinal canal stenosis before and after treatment with Lipo prostaglandin E1. RESULTS: In six of these patients, dilation of the running blood vessels was observed immediately after administration. In all of the patients who exhibited a dilation of vessels on the surface of the cauda equina, intermittent claudication and lower extremity pain and/or numbness lessened immediately after examination. However, none of the patients who exhibited no morphological changes in the vessels along the cauda equina after administration of Lipo prostaglandin E1 experienced any improvement of symptoms at the time of examination. CONCLUSION: Results of this study suggest that Lipo prostaglandin E1 may enhance blood flow in the cauda equina and improve clinical symptoms in some patients with lumbar spinal stenosis.     

Blood flow measurement in experimental chronic cauda equina compression in dogs: changes in blood flow at various conditions

The purpose of this study was to present a simple method of measurement of blood flow in the nerve root, assess the reliability of this method, and examine the changes of blood flow in chronic cauda equina compression in an experimental setting. A total of 15 dogs were used to determine the blood flow of cauda equina in normal (n = 5), sham (n = 5), and 10 mm Hg compressed cauda equina for 1 week (n = 5). The speed of blood flow was calculated using a specially designed microscope supplied with a video camera. Blood flow in chronic 10 mm Hg compression decreased compared with the sham and normal groups. The kappa value was between 0.75 and 0.96. We conclude that this method might be useful for measurement of blood flow in the nerve root and for confirming the reduction in blood flow of compressed cauda equina.     

Vasodilative effects of prostaglandin E<Subscript>1</Subscript> derivate on arteries of nerve roots in a canine model of a chronically compressed cauda equina

Background  

Reduction of blood flow is important in the induction of neurogenic intermittent claudication (NIC) in lumbar spinal canal stenosis. PGE₁ improves the mean walking distance in patients with NIC type cauda equina compression. PGE₁ derivate might be effective in dilating blood vessels and improving blood flow in nerve roots with chronically compressed cauda equina. The aim of this study was to assess whether PGE₁ derivate has vasodilatory effects on both arteries and veins in a canine model of chronic cauda equina compression.     

实验性腰椎管狭窄马尾神经动态负荷下血流量的变化

目的研究高频率刺激(high frequency stimulation,HFS)及压迫追加的动态负荷下双节段受压马尾神经血流量的变化,探讨神经源性间歇跛行的发病机制. 方法 SD大鼠30只,分成5组,每组6只.均行单纯L5椎板切除,检测血流量1小时后,将4个实验组制成L4及L6节段30%的双节段狭窄.施加静态压迫2小时后,实验1组不施加动态负荷(dynamic burden, DB);实验2组只施加HFS 6分钟;实验3组同时施加HFS和压迫追加6分钟;实验4组只行压迫追加6分钟;对照组为单纯L5椎板切除及HFS 6分钟.应用激光多普勒血流仪检测马尾神经血流量. 结果对照组马尾神经血流量在最初2小时无显著变化,施加HFS时显著升高至初始值的186.4%±31.5% (P<0.05).实验1组血流量为110.4%±7.5%(与初始值比较,P>0.05);实验2组血流量无显著变化111.6%±17.6%(与初始值比较,P>0.05);实验3组血流量降至初始值的65.3%±10.7%(P<0.05);实验4组血流量降至初始值的60.1%±9.2% (P<0.01),与实验3组无显著差异(P>0.05). 结论神经电活动增加时,马尾神经双节段压迫可造成其相对缺血;若压迫程度同时增加,马尾神经血流量显著降低,造成绝对缺血.     

Spinal stenosis: assessment of motor function,VEGF expression and angiogenesis in an experimental model in the rat

Reduction of blood flow in compressed nerve roots is considered as one important mechanism of induction of neurogenic intermittent claudication in lumbar spinal canal stenosis. Vascular endothelial growth factor (VEGF) is a potent stimulator of angiogenesis, and is increased in expression in hypoxic conditions. The objective of this study was to examine if cauda equina compression affects motor function and induces expression of VEGF and angiogenesis. The cauda equina was compressed by placing a piece of silicone rubber into the L5 epidural space. Walking duration was examined by rota-rod testing. The compressed parts of the cauda equina and L5 dorsal root ganglion (DRG) were removed at 3, 7, 14, or 28 days after surgery, and processed for immunohistochemistry for VEGF and Factor VIII (marker for vascular endothelial cells). Numbers of VEGF-immunoreactive (IR) cells and vascular density were examined. Walking duration was decreased after induction of cauda equina compression. The number of VEGF-IR cells in the cauda equina and DRG was significantly increased at 3, 14, and 28 days after cauda equina compression, compared with sham-operated rats (P < 0.05). Vascular density in the cauda equina was not increased at any of the time points examined. Cauda equina compression decreased walking duration, and induced VEGF expression in nerve roots and DRG.     

A case of traumatic spinal subarachnoid hematoma causing compression of the cauda equina]

A case of traumatic spinal subarachnoid hematoma causing compression of the cauda equina is reported here. The patient, a 76 year-old woman, who had fallen down by accident 1 month before, was admitted to our hospital presenting lumbar pain radiating into her right thigh, monoplegia of the right leg and urinary incontinence. Myelography and metrizamide CT demonstrated a filling defect mimicking intradural extramedullary tumor at the level of L1 and L2. Magnetic resonance imagings (MRI) revealed a subacute or chronic hematoma compressing the conus medullaris and the cauda equina. Operation was performed and an old hematoma, which occupied most of the spinal subarachnoid space and compressed the conus and cauda equina from right to left, was removed. No definite bleeding point was detected and no traumatic change was seen on the cord. Neither tumor nor abnormal vessel was detected. After surgery, the symptoms improved partially. On a review of the literature, we found only 4 cases of traumatic spinal subarachnoid hematoma, all of which occupied the cervical or thoracic portion of the spine. Our case is the first report, except for the cases following lumbar spinal tap, of traumatic spinal subarachnoid hematoma causing compression of the cauda equina. Though usually blood in CSF diffuses immediately, a clot may be formed when a large amount of bleeding obstructs the spinal canal. In our case, furthermore, deformity and narrowing of the spinal canal had preceded for many years, following lumbar vertebral compressed fracture related with osteoporosis. This might have promoted the process of canal obstruction and clot formation.(ABSTRACT TRUNCATED AT 250 WORDS)     

大鼠非压迫性髓核突出模型的建立

目的:设计一种新的非压迫性腰椎间盘髓核突出动物模型。方法:16只SD雄性大鼠随机分对照组和实验组,分别将生理盐水和大鼠自身尾椎髓核混悬液注射到腰椎硬膜外腔,对其马尾神经传导速度和神经根组织形态学进行观察。结果:无明显机械压迫情况下,大鼠硬膜外移植自体髓核能使马尾神经根传导速度和组织形态产生明显改变。结论:本动物模型简单、可靠、费用低廉,为进一步研究腰椎间盘突出症提供了一种动物模型。     

前列腺素E1在动态负荷下对大鼠受压马尾神经电生理的影响

目的：研究动态因素下前列腺索E1对大鼠马尾神经电生理变化的影响。方法：分4组，每组6只。除正常对照组，其他三个实验组使用硅胶片插入L4及L6椎管造成横截面积减小30％的双节段狭窄。压迫施加2h后，三个实验组分别施加动态负荷(高频率刺激和/或压迫追加)6min。PGE1压迫增加组在施加动态负荷前给与前列腺素E1。结果：压迫2h后，各实验组神经传导速度均显著下降。动态负荷下，HFS褐压迫增加组出现了神经传导阻滞，而应用了前列腺累E1的PGE4压迫增加组则部分避免了其发生。结论：受压状态中的马尾神经在动态负荷下，前列腺索E1可以防止神经传导阻滞的发生，对神经传导功有保护作用，它可以作为一种非手术治疗腰椎管狭窄症的选择。     

Nutritional supply to the cauda equina in lumbar adhesive arachnoiditis in rats

Laminectomy-induced cauda equina adhesion has been proved by rat experiments and postoperative serial MRI in humans. A degenerative change of the cauda equina has been proved when cauda equina adhesion has been prolonged. Since it has not been reported how the nutritional supply is changed in such a condition, we evaluated the glucose supply to the adhered cauda equina in rats. Wistar rats were divided into the following three groups: the control group which received no operation, the laminectomy group which underwent L5-L6 laminectomy only, and the koalin group which received 5 mg of kaolin on the dorsal extradural space following L5-L6 laminectomy. Based on ³H-methyl-glucose uptake study, we analyzed (1) glucose transport from the intraneural vessels to the nerve tissue, and (2) glucose transport from the cerebrospinal fluid to the nerve tissue. We evaluated the relation between the severity of cauda equina adhesion and ³H uptake into the cauda equina. Cauda equina adhesion was observed in 2 of 12 rats in the control group, in 3 of 12 rats in the laminectomy group, and in 18 of 20 rats in the kaolin group. In the ³H-methyl-glucose uptake study, at 12 weeks the glucose transport to the cauda equina from the vessels increased by 44%, and that from the cerebrospinal fluid decreased by 64% in the kaolin group compared with thecontrol group. In the condition of complete cauda equina adhesion, the glucose transport to the cauda equina from the vessels increased by 53% and that from the cerebrospinal fluid remarkably decreased by 72% compared with the normal cauda equina. Considering the greater nutritional importance of the cerebrospinal fluid in the cauda equina, it is most likely that the impairment of nutritional supply to adhered cauda equina may lead to eventual neural degeneration. Received: 8 September 1998 Revised: 28 December 1998 Accepted: 10 February 1999     

The effects of a 5-HT2A receptor antagonist on blood flow in lumbar disc herniation : application of nucleus pulposus in a canine model

Blood vessel clots are found around the nerve root in patients with lumbar disc herniation. Thrombosis formation in the experimental application of nucleus pulposus to the nerve root has been shown in histological studies. In addition, reduction of blood flow and nerve conduction velocity are induced by the application of nucleus pulposus, which mimics lumbar disc herniation. In patients with lumbar disc herniation, nerve root block, which is thought to increase nerve blood flow, improves radiculopathy. 5-HT_2A receptor antagonists are used in chronic arterial occlusive diseases to improve blood flow and have been reported to work as well as nonsteroidal anti-inflammatory drugs in improving radiculopathy due to lumbar disc herniation in clinical studies. This study investigated the effects of a 5-HT_2A receptor antagonist on blood vessel diameter and blood flow in a canine experimental model of lumbar disc herniation. A total of 13 dogs were used. The animals were divided into three experimental groups and surgery was performed 1 week before measurements. In the nucleus pulposus group (NP; n = 5), the nucleus pulposus was applied to the nerve roots from the ventral side. In the sham group (n = 5), nucleus pulposus was not applied. In the naïve group (n = 3), the animals did not undergo surgery. Measurements of vessel diameter and blood flow were done before and after administration of saline and drugs. The diameters and blood flow volume of the observed blood vessels were measured on video-recordings every 10 min for 65 min. In all groups, vessel diameter and blood flow did not change before or after administration of saline. In the NP and sham groups, vessel diameter and blood flow increased significantly after administration of 5-HTRA compared with the naïve group. 5-HTRA improved blood vessel diameter and blood flow in the nerve roots inflamed by the application of nucleus pulposus but not in the intact nerve roots. 5-HTRA might be a potential agent to improve blood flow in the nerve roots of patients with lumbar disc herniation.     

Hemodynamic comparison of microsurgical repairs for large arterial defects

Twenty-eight femoral arteries in 14 rats were used to compare transverse closures and end-to-end anastomoses in blood vessels approximately 1 mm in diameter. The transverse closures were applied to arteriectomies created by excising one-half the circumference of the vessel over a length of 1 mm. The end-to-end anastomoses were performed after resecting a 1-mm segment. Recordings were made of pre-and postrepair flow velocity and three-point diameter measurements every 5 minutes using a 20-MHz pulsed Doppler velocimeter and digimatic caliper. Maximum reductions in flow velocity were 18% and 31% for the transverse repair and end-to-end anastomosis, respectively. Otherwise, intergroup comparisons of the postrepair normalization of both flow velocity and vessel diameter showed few significant differences (P < 0.05). We conclude that arterial defects involving no more than half the diameter of the vessel can be effectively repaired in significantly less time using the transverse closure. © 1994 Wiley-Liss, Inc.     

腰椎骨折脱位患者马尾神经修复的临床观察

目的：观察腰椎骨折脱位后马尾神经损伤修复的临床效果。方法：对8例L2或L3骨折脱位伴损伤平面以下全瘫的患者行手术整复固定骨折脱位后用纤维蛋白胶粘合断裂的马尾神经，观察患者神经功能恢复情况。结果：新鲜的腰椎骨折脱位患者马尾神经损伤修复后大腿肌肉功能都有恢复，膝关节以下肌肉没有恢复；陈旧性损伤无任何恢复。感觉均无任何恢复。结论：为提高神经功能的恢复，腰椎骨折脱位后马尾神经的损伤应给予修复，用纤维蛋白胶粘合断裂的马尾神经是一种可行的方法。     

继发于腰椎间盘突出的马尾神经综合征

【摘要]目的 阐明马尾神经综合征术后神经功能结果及其临床意义。方法 对因腰椎间盘突出导致的马尾神经综合征患者33例分为早期手术组和延迟手术组进行回顾性分析。早期手术组48小时内手术20例,其中门例在24小时内手术。延迟手术组13例在马尾神经综合征表现48小时之后予以手术,平均延迟7天,其中9例延迟手术者系医源性延迟。结果 延迟手术者膀眺功能障碍、运动功能障碍和持续性疼痛的发生率明显大于早期手术组(P<0刀5)。结论 对因腰椎间盘突出所致的马尾神经综合征应尽早手术。     

Tumoral calcinosis of the lumbar meninges: case report

OBJECTIVE AND IMPORTANCE: Tumoral calcinosis is a rare disorder of unknown origin. Tumoral calcinosis involving the spine is extremely rare. This is the first case of tumoral calcinosis localized in the dura mater of the lumbar spine. CLINICAL PRESENTATION: This 55-year-old male patient presented with tumoral calcinosis of the lumbar meninges. T1-weighted, sagittal magnetic resonance imaging scans of the lumbar spine revealed a round mass of slightly increased intensity with high-intensity margins, located posterior to the cauda equina at the L4-L5 level. The cauda equina was severely compressed anteriorly. T2-weighted scans revealed that the mass was composed of a high-intensity area with low-intensity margins. T1-weighted magnetic resonance imaging scans obtained after intravenous gadolinium administration revealed some enhancement at the margins. INTERVENTION: The mass lesion was totally resected. Three years after surgery, no recurrence was observed in follow-up magnetic resonance imaging scans. CONCLUSION: Although tumoral calcinosis is a rare cause of mass lesions of the lumbar spine, it should be considered in differential diagnoses. If the lesion can be totally resected, the prognosis should be good, similar to that for general tumoral calcinosis.     

家犬马尾及其受压模型的建立

目的:观察家犬腰骶部神经结构与人类马尾的异同点,建立与人类马尾受压类似的动物模型,研究其病理变化。方法:废弃家犬4只经颈静脉加压灌注后,自后侧入路剖开腰骶椎管,测量椎管的直径及硬膜外间隙,观察马尾神经的组成及走行。2只家犬麻醉后自L6椎板潜行置入水囊,关闭注水,用诱发电位和MR检测。结果:犬的腰椎共有7节,椎管在L6水平横径为1.4~1.6 cm,前后径1.2~1.4 cm,硬膜外间隙约0.2 cm,共计5对神经根围绕在终丝斜向外下形成马尾。脊髓圆锥下端平L6水平。在L5,6椎板下,硬膜外间隙置入硅胶水囊后,在未注水加压时,犬的行为学及诱发电位均无改变;逐渐注水后随着压力的上升,行为学及诱发电位均有相应的改变。MR可以显示相对应的水囊所占椎管的容积。结论:家犬马尾与人类的相似,硅胶水囊置入和注水法,重复性好,动物生存率高,可以成功建立马尾慢性压迫模型。     

不同程度椎管狭窄对马尾神经脑脊液营养来源影响的实验研究

目的：探讨不同程度腰椎椎管狭窄对马尾神经脑脊液营养来源的影响。方法：将^3H-甲基葡萄糖注入不同程度腰椎椎狭窄模型动物的脑脊液中，5min后分别测定脑脊液（Rcsf)和不同节段马尾神经组织（R）中放射性同位素的放射强度，并换算成R／Rcsf。结果：25％、50％狭窄组狭窄段及以远段马尾神经的R／Rcsf较正常组和对照组均有非常显著（P＜0．001）或显著性（P＜0．05）降低，50％狭窄组较25％狭窄组降低更加显著（P＜0．05）。结论：腰椎椎管狭窄在狭窄段及狭窄以远段造成了马尾神经脑脊液来源的营养障碍，并随狭窄程度的增加而愈加明显。马尾神经脑脊液来源的营养障碍可能是马尾神经受损表现的重要病理生理基础。     

马尾神经功能障碍型腰椎间盘突出症的诊断与治疗

目的：介绍合并有马尾神经功能障碍的腰椎间盘突出症的诊断与治疗方法。方法：发生马尾神经功能障碍型腰椎间盘突出症的病人，大多为青壮年，强体力劳动者或体育运动员，因急性腰扭伤而发病。受伤后出现瘫痪症状和马鞍区麻痹、大小便失禁等现象，经X线拍片、CT和MRI检查，明确诊断后，应立即进行手术治疗。结果：作者报告10例，均经关节突间或半椎板切除入路，切除巨块型椎间盘，彻底减压马尾神经，术后均能得到良好的功能恢复，疼痛消失，唯大小便的功能恢复较迟，约在术后1～3周后尚能恢复。结论：马尾神经功能障碍型腰椎间盘突出症，应与马尾肿瘤相鉴别，一旦被确诊为巨块型腰椎间盘突出症，就应立即进行手术治疗，越早手术效果越好。     

Anterior lumbar interbody fusion: changes in area of the dural tube, disc height, and prevalence of cauda equina adhesion in magnetic resonance images

OBJECTIVE: Many investigators have reported satisfactory outcome in anterior lumbar interbody fusion (ALIF) performed for lumbar disc herniation or "multiply operated back" (MOB), but without comparing preoperative and postoperative dural tube area and cauda equina adhesion in magnetic resonance imaging (MRI). We conducted this study to determine these data in ALIF performed for lumbar disc herniation and MOB. METHODS: Thirty-two patients who underwent ALIF, involving 38 discs, were studied. In MRI obtained before and after surgery (interval 9-48 months, mean 19.2 months), cross-sectional areas of the lumbar dural tube were measured from axial T2-weighted images using a computer-linked digitizer. At 30 disc levels operated on, the cauda was identified in images; cauda equina adhesions were classified according to Matsui et al (grade I-III). Clinical improvement was scored. RESULTS: Bony union was observed in radiographs of all patients. Preoperative and postoperative cross-sectional areas of the lumbar dural tube were 1.32 +/- 0.4 and 1.87 +/- 0.5 cm, respectively, and expansion ratio was 1.43 +/- 0.4. Recovery did not correlate with expansion ratio. Positive correlation was noted between expansion ratio and disc height ratio. At 30 disc levels where cauda equina was identified, 22 represented grade I and 8 represented grade II. At three of the latter, prior surgery had been performed via a posterior approach. CONCLUSIONS: No significant difference was noted in occurrence of grade II adhesions between primary ALIF and ALIF performed for MOB. Dural tube expansion was accomplished even without exposure of the tube, and cauda equina adhesion was uncommon in primary ALIF.     

Changes in hemodynamics of the carotid and middle cerebral arteries before and after endoscopic sympathectomy in patients with palmar hyperhidrosis: preliminary results

OBJECT: The purpose of this study was to analyze the change in carotid and middle cerebral artery (MCA) hemodynamics before and after endoscopic upper thoracic sympathectomy in patients with palmar hyperhidrosis (PH). METHODS: Sixty-eight patients with PH (35 males and 33 females) for whom the average age was 24.5+/-10.7 years (+/- standard deviation) were recruited into this study. These patients all underwent routine upper T-2 sympathectomy to treat their PH. Ultrasonography studies of the carotid arteries (CAs) and MCA were obtained in each patient before and after T-2 sympathectomy. The blood flow volume, flow velocity, and resistivity index (RI) in the bilateral common CAs (CCAs), internal CAs (ICAs), and external CAs (ECAs) were evaluated using duplex ultrasonography. The systolic peak velocity, mean velocity, diastolic peak velocity, pulsatility index, and RI of the bilateral MCAs were evaluated using transcranial Doppler ultrasonography. Blood pressure and heart rate were also recorded during this study. The Student paired t-test was used to analyze the differences between studies before and after bilateral T-2 sympathectomy. There was a significant reduction in diastolic pressure after T-2 sympathectomy (p = 0.003), but not in systolic pressure or heart rate. The vessel diameter was increased after sympathectomy in the left CAs and right CCA. The T-2 sympathectomy led to significant elevation of blood flow volume and RI in the left CCA, ICA, and ECA (p < 0.05). The authors found significant increases in maximum flow velocity and RI in the left MCA (p < 0.05). CONCLUSIONS: Patients who underwent T-2 sympathectomy demonstrated a significant increase in blood flow volume and flow velocities of the CAs and MCA, especially on the left side. Asymmetry of sympathetic influence on the hemodynamics of the CAs and MCA was noted. The usefulness of sympathectomy for the treatment of ischemic cardiovascular and cerebrovascular disease deserves further investigation.