Bilateral Mirror Image Cervical Neurofibroma in an Adult with Neurofibromatosis Type 1

Neurofibromatosis type 1 (NF1) is an autosomal dominant disorder characterised by various phenotypic features like hyperpigmented spots, neurofibromas, Lisch nodules, skeletal abnormalities and tendency to develop neoplasms. Only few cases of Non-Familial Spinal Neurofibromatosis-1 (Non-FSNF1) have been described in literature with tumors involving the spinal roots at every level being even rarer. We reported an interesting case of bilateral symmetrical cervical neurofibroma with multiple spinal neurofibromas appearing as mirror image on CT, associated with non familial NF-1 as a rare presentation in a 25-year-old adult male.

Observation on therapeutic effect of nerve root pulsed radiofrequency in elderly acute herpes zoster / 重庆医学

Objective To evaluate the effect of nerve root pulsed radiofrequency combined with neurotropin(NTP) by epidural injection for treating neuralgia in elderly patients with herpeszoster. Methods Sixty patients aged 60-85 years old with herpes zoster neuralgia were selected and divided into the observation group and control group. The control group was given the epidural injection of NTP,while the observation group was given the therapy of nerve root pulsed radiofrequency combined with NTP. Then the curative effects were observed in the two groups. The visual analogue scale (VSA) and Pittsburgh sleep quality index (PSQI) were used to evaluate the status of sleep improvement and the occurrence rate of post herpetic neuralgia (PHN) was also calculated. Results The VAS and PSQI scores at each time points of 1,3,6 months in the both groups were significantly superior to those before treatment (P<0.05). Compared with the control group,the VAS score at each time point after treatment in the observation group was significantly superior to that in the control group(P<0.05) ;The PHN occurrence rate after 6 months of treatment in the observation group was significantly lower than that in the control group (P<0.05). Conclusion Nerve root pulsed radiofrequency combined with NTP by epidural injection is a good method for treating neuralgia in elderly patients with herpes zoster.

Analysis of SNRB in patients with lumbar radiculopathy resistant to conservative treatment.

Background: The transforaminal application performed with SNRB (Selective nerve root blocks) should be more accurate. Moreover, the amount of corticosteroid and local anesthetic can be reduced compared to the amount of these agents administered with the epidural steroid. Methods: Prospective study of 72 patients with low back pain done in Sri Ramachandra medical centre, Chennai during April 2012 to April 2014. 46 patients were diagnosed to have inter vertebral disc and 26 patients with Lumbar canal stenosis. The patients were evaluated using VAS score and Oswestry disability index. The indication and determination of the therapeutic SNRB level was established by the spine surgeon after all the diagnostic test results had been obtained and after a detailed discussion with the patient. After confirming the correct placement of spinal needle with a short bevel with the help of contrast, a solution of 1ml of 0.5% sensorcaine with 1 ml of triamcinolone acetonide (Inj. kenocort) is injected. Results: Only 2 patients out of 72 had persistent pain and underwent surgery. 60 of our patients were comfortable and were able to proceed with their normal life/day to day activities following the administration of one block. Conclusion: Selective nerve root block is effective and less invasive intervention, and serves as an adjunct to non-operative treatment. The blocks give the best result in disc herniation cases, followed by favorable results in foraminal stenosis.

Management of Patients with L2 Spinal Nerve Root Block Who Are Suffering from Low Back and Referred Pain

STUDY DESIGN: Prospective clinical study. OBJECTIVES: The aim of the study was to verify the effectiveness of L2 spinal nerve root block for patients who are suffering from low back pain and referred pain with compound causes. SUMMARY OF LITERATURE REVIEW: Most of low back pain and referred pain arises from discs, facet joints and sacroiliac joints. All structures above have the pain perception pathway through sympathetic nerves with a connection to L2 spinal nerves. MATERIALS AND METHODS: We selected patients with low back pain and referred pain for more than 2 weeks. Each 50 patients were randomly allocated to an experimental and a control group.The experimental group underwent a L2 spinal nerve root block with 2cc of 0.25% bupibacaine at the symptom dominant side. The control group underwent a skin infiltration with 2cc of 2% lidocaine only. The pain was assessed with a visual analogue scale (VAS) consisting of 100 points at 5minutes, day 1, day 3, day 5, day 7 and day 30 postprocedure. RESULTS: Both groups showed a significant improvement after the procedures(p=0.000). However, a greater improvement was shown in the experimental group(p=0.000). In the individual analysis, the experimental group had improved as time elapsed and the significancewas maintained until 30 days. However, in control group, the significance was lost at day 30. CONCLUSION: L2 spinal nerve root block is recognized to reduce the low back and referred pains which arise from compound causes in a degenerative spinal disease.

The Efficacy and Persistence of Selective Nerve Root Block under Fluoroscopic Guidance for Cervical Radiculopathy

STUDY DESIGN: Retrospective study. OBJECTIVES: To investigate the outcomes of fluoroscopically guided selective nerve root block as a nonsurgical treatment for cervical radiculopathy. OVERVIEW OF LITERATURE: Only a few studies have addressed the efficacy and persistence of cervical nerve root block. METHODS: This retrospective study was conducted on 28 consecutive patients with radicular pain due to cervical disc disease or cervical spondylosis. Myelopathy was excluded. Cervical nerve root blocks were administered every 2 weeks, up to 3 times. Outcomes were measured by comparing visual analogue scale (VAS) scores, patient satisfaction, and medication usage before the procedure and at 1 week and 3, 6, and 12 months after the procedure. In addition, complications associated with the procedure and need for other treatments were evaluated. RESULTS: The average preoperative VAS score was 7.8 (range, 5 to 10), and this changed to 2.9 (range, 1 to 7) at 3 months and 4.6 (range, 2 to 7) at 12 months. Patient satisfaction was 71% at 3 months and 50% at 12 months. Five patients used medication at 3 months, whereas 13 used medication at 12 months. Average symptom free duration after the procedure was 7.8 months (range, 1 to 12 months). Two patients were treated surgically. Only two minor complications were noted; transient ptosis with Horner's syndrome and transient causalgia. CONCLUSIONS: Although selective nerve root block for cervical radiculopathy is limited as a definitive treatment, it appears to be useful in terms of providing relief from radicular pain in about 50% of patients at 12 months.

Differentiation between Symptomatic and Asymptomatic Extraforaminal Stenosis in Lumbosacral Transitional Vertebra: Role of Three-Dimensional Magnetic Resonance Lumbosacral Radiculography

OBJECTIVE: To investigate the role of lumbosacral radiculography using 3-dimentional (3D) magnetic resonance (MR) rendering for diagnostic information of symptomatic extraforaminal stenosis in lumbosacral transitional vertebra. MATERIALS AND METHODS: The study population consisted of 18 patients with symptomatic (n = 10) and asymptomatic extraforaminal stenosis (n = 8) in lumbosacral transitional vertebra. Each patient underwent 3D coronal fast-field echo sequences with selective water excitation using the principles of the selective excitation technique (Proset imaging). Morphologic changes of the L5 nerve roots at the symptomatic and asymptomatic extraforaminal stenosis were evaluated on 3D MR rendered images of the lumbosacral spine. RESULTS: Ten cases with symptomatic extraforaminal stenosis showed hyperplasia and degenerative osteophytes of the sacral ala and/or osteophytes at the lateral margin of the L5 body. On 3D MR lumbosacral radiculography, indentation of the L5 nerve roots was found in two cases, while swelling of the nerve roots was seen in eight cases at the exiting nerve root. Eight cases with asymptomatic extraforaminal stenosis showed hyperplasia and degenerative osteophytes of the sacral ala and/or osteophytes at the lateral margin of the L5 body. Based on 3D MR lumbosacral radiculography, indentation or swelling of the L5 nerve roots was not found in any cases with asymptomatic extraforaminal stenosis. CONCLUSION: Results from 3D MR lumbosacral radiculography Indicate the indentation or swelling of the L5 nerve root in symptomatic extraforaminal stenosis. Based on these findings, 3D MR radiculography may be helpful in the diagnosis of the symptomatic extraforaminal stenosis with lumbosacral transitional vertebra.

Longitud de las raíces cervicales en resonancia magnética: relación con la parálisis postoperatoria de la quinta raíz cervical / Medida do comprimento das raízes cervicais pela ressonância magnética: relação com a paralisia pós-operatória e a quinta raiz cervical / Cervical nerve root length in magnetic resonance imaging: its relationship with postoperative fifth root palsy

OBJETIVO: determinar la longitud de la raíz C5. MÉTODOS: se estudiaron con resonancia magnética (Signa 1,5 T, cortes axiales de 5 mm de espesura, TR=850, TE=26, FOV=200) las columnas cervicales de 50 pacientes (29 hombres - 21 mujeres) entre 26 y 68 años. Se incluyeron solo casos con cervicalgia y/o cervicobraquialgia. Se midió (en mm) la longitud de las raíces cervicales tercera a séptima, derechas e izquierdas. La comparación de los promedios se realizó a través del análisis de varianza, para un nivel de significación α=0,05 con IC de 95 por ciento. Las comparaciones post-hoc se hicieron empleando el test de Bonferroni. RESULTADOS: se observó que el lado (derecho o izquierdo) y el sexo (varón o mujer) no tuvieron incidencia estadísticamente significativa en el valor de la longitud de las raíces (p>0,05). La raíz C5 tuvo un tamaño significativamente diferente (p<0,05) a cada una de las raíces, pero se comprobó que la raíz más corta era C3. CONCLUSIÓN: la raíz C5 no es la más corta.

OBJETIVO: determinar o comprimento da raiz C5. MÉTODOS: as colunas cervicais de 50 pacientes (29 homens - 21 mulheres), com idades entre 26 e 68 anos foram analisadas com ressonância magnética (Signa 1,5 T, cortes axiais de 5 mm de espessura, TR=850, TE=26, FOV=200). Foram incluídos casos com dor cervical e/ou cervicobraquial. O comprimento das raízes C3 a C7, à direita e esquerda, foi medido. A comparação das médias foi realizada com uma análise de variância para um nível de significação α = 0,05 com IC de 95 por cento. As comparações post-hoc foram feitas com o teste de Bonferroni. RESULTADOS: foi observado que o lado (direito ou esquerdo) e o sexo (homem ou mulher) não tiveram incidência estatística significante em relação ao valor do comprimento das raízes. A raiz C5 evidenciou um tamanho significativamente diferente (p<0,05) do resto das raízes analisadas, mais comprovou-se que aquela mais curta foi C3. CONCLUSÃO: a raiz C5 não é a mais curta.

OBJECTIVE: to determine the length of the C5 root. METHODS: the cervical spines of 50 patients (29 male and 21 female), between 26 and 68 years old, were studied with magnetic resonance imaging (Signa 1.5 T, axial images with 5 mm thickness, TR=850, TE=26, FOV=200). Only patients with cervical and/or arm pain were included. We measured (mm) the length of the right and left, third to seventh cervical roots. A comparison of the average lengths was made with the variance analysis for α=0.05 significance level and a 95 percent CI. Post-hoc comparisons were made with the Bonferroni test. RESULTS: it was noted that the side (right or left) and gender (male or female) had no influence on the roots' length differences (p>0.05). The C5 root had a length significantly different (p<0.05) from the others, but the shorter was C3. CONCLUSION: C5 root is not the shortest.

Transient quadriplegia after fluoroscopic-guided selective cervical nerve root block in a patient who received cervical interbody fusion: A case report / 대한마취과학회지

Selective cervical nerve root block is executed for patients who have symptoms of cervical radiculopathy for diagnostic and therapeutic purposes. However several catastrophic complications caused by this procedure have been reported including neurological complications. A 43-year-old male received a C5 selective cervical nerve root block procedure due to continuous radiating pain even after cervical discectomy and interbody fusion was performed. At the time of the procedure, the contrast outline revealed reflux of the nerve root and epidural space. But after the procedure was performed, the patient experienced decreased sensation in the upper and low extremities as well as motor paralysis of both extremities. Our sspecting diagnosis was anterior spinal artery syndrome but both sensory and motor functions were subsequently recovered within a few hours after the procedure was completed. Due to the difficult nature of this case, we reported these complications and reviewed current literature related to this study.

The Usefulness of Selective Spinal Nerve Root Block / 대한척추외과학회지

PURPOSE: A retrospective study on the usefulness of selective spinal nerve root block among lumbar herniated intervertebral disc (HIVD), spinal stenosis and postoperative syndrome over 10 years. MATERIAL AND METHOD: From a total 1195 patients, whose symptoms were not improved by conservative treatment, 505 treated by selective nerve root block were divided into 3 groups; 150 (29.7%) with HIVD, 313 (62.0%) with spinal stenosis and 42 with postoperative syndrome, and were followed up from Oct. 1992 to Dec 2001. The degree of pain and activity were evaluated by a visual analogue scale method at the out-patient department or through telephone interviews. RESULTS: The end-results of selective spinal nerve root block, with more than 50% reduction in pain occurred in 380 (75.3%) of the 505 patients. The effectiveness was greater in young patients with HIVD than elderly patients with spinal stenosis. After discharge, 160 patients (31.7%) needed no other treatment: 14 (31.0%) with an extrusion type HIVD and 17 (20.0%) with spondylolisthesis. The only 98 patients (19.4%) needed a surgical procedure after selective spinal nerve root block. CONCLUSION: Selective spinal nerve root block in patients with lower back and radiating pain is a valuable conservative treatment to quickly improved symptoms and avoid surgical procedures and the continuous administration of drugs.

Clinical Effect of Fluoroscopy Guided Interventional Muscle and Nerve Stimulation (IMNS) on Intractable Spinal Origin Pain / 대한마취과학회지

BACKGROUND: This study was performed to characterize the long term observations after the use of a round needle for the management of chronic musculoskeletal pain. METHODS: The study subjects were 71 patients with musculoskeletal pain who had failed at least two previous treatments. They received interventional muscle and nerve stimulation (IMNS) using a 0.8 to 1.2 mm diameter dry needle with a streamlined shaped and a round tip from March, 2002 to July, 2002. Patients received IMNS as a bilateral segmental treatment mainly in the paraspinal, sometimes in the radicular region at 2 week intervals. The follow-up rate was 97%. Follow-up occurred at 6 months after the last IMNS treatment. Main outcomes were measured using a pain relief scale and a visual analog scale. RESULTS: Spinal stenosis, Herniated Nucleus Pulposus and an unclassified group (radicular symptoms existed, but no correlatable radiographic findings of radiculopathy were found) produced positive responses whereas fibromyalgia and failed back surgery syndrome did not. CONCLUSIONS: These results reveal that IMNS has a potential value in musculoskeletal pain originating from a spinal nerve root.

Effect of selective posterior rhizotomy on children with spastic cerebral palsy / 中国康复理论与实践

@#ObjectiveTo observe the effect of selective posterior rhizotomy (SPR) on children with spastic cerebral palsy.Methods517 spastic cerebral palsy cases were operated on by SPR, and a following up was performed for 24 months. After operation, curative effect of SPR was examined and evaluated.Results298 cases had excellent effect (57.6%); 187 cases had good effect (36.2%).Conclusion SPR is very effective for children with spastic cerebral palsy.

Intraoperative Spinal Nerve Root Injuries during Surgery for Degenerative Low Back Disease / 대한척추외과학회지

STUDY DESIGN: A retrospective study OBJECTIVE: To analyze incidence, causes and prognosis of the spinal nerve root injury during the degenerative low back surgery. SUMMARY OF LITERATURE REVIEW: There were very few studies about intraoperative spinal nerve root injuries during low back surgery. MATERIALS AND METHODS: Six hundred and twenty seven patients underwent degenerative low back surgery from Jan 1990 to Jan 2001 were included in this study. All patients were operated on by the first author and operation records made by the author himself were reviewed. Eight cases of intraoperative spinal nerve root injury were identified and causes and level of injuries, preoperative diagnosis, types of surgery and follow-up clinical results were analyzed. RESULTS: Eight cases of nerve root injury were developed during 5 posterior laminotomies for discectomy and 3 instrumentation and fusion. Spinal nerve root injuries were caused by Kerrison punch in 4 cases, pituitary forcep in 2, rongeur in 1, and not certain but probably by Kerrison punch in 1 case. The levels of injuries were 5th lumbar nerve root in 4 cases, and 1st sacral nerve root and 2nd lumbar nerve root in 1 case respectively. Two cases had sacral nerve rootlet injury with paramedian dural tear but the level of root injury was uncertain. Six of 8 patients had symptoms. There were sensory loss in 4 patients, pain in 2, and one patient had both sensory loss and loss of big toe extension power. Neurological symptoms were not improved throughout the follow-up period, but 2 patients who had pain were resolved their symptoms by 3 months. CONCLUSIONS: Incidental spinal nerve root injury occurred in 1.3 percentage of the patients who underwent low back surgery. Half of them had neurologic symptoms and they showed poor prognosis. However motor deficit was relatively uncommon and it might be related to the anatomical characteristics of spinal nerve root.

Experimental study of protective effect of local infiltration of methylprednisolone on injured spinal nerve root / 中国临床药理学与治疗学

AimTo observe the effect of infiltration of Methylprednisolone on injured spinal nerve root and the protective function of Methylprednisolone to non-impressed spinal nerve root lesion. Methods The spinal nerve roots were injured in 20 rabbits. Three days later local Methylprednisolone infiltration of spinal nerve root profromed in rabbits in experiment group, while rabbits in the control roup received equal amount of 0.9% natriichloridi instead. The conduct velocity of spinal nerve root was measured one week after operation. The histological change of spinal nerve root and immunohistochemical stain of posterior horn of spine were observed by microscope. Results The conduct velocity was recovered obviously in experiment group. In observation of spinal nerve we found the edema and hyperaemia of matrix were impaired obviously, the lesion focus was minimized, the amount of inflammatory cells was decreased. The area of substance P positive fiber and its terminus in posterior of spinal was smaller in experiment group remarkably than in control group. ConclusionsThe local infiltration of Methylprednisolone can relieve inflammation, inhibit the transmission of pain and accelerate recovery of spinal nerve root.

Posterior approach low lumbar nerve root sheath decompression under microendoscope:Clinical report of 39 cases / 中国微创外科杂志

Objective To investigate the method and the effect of posterior approach low lumbar spinal nerve root sheath decompression under microendoscope (MED-Ⅱ). Methods Thirty-nine patients with low lumbar disc herniation, accompanying severe preoperative limb numbness and radiculalgia, who were found obvious edema of nerve root with adhesion during surgery, entered the study. In the course of lumbar discectomy, a self-made mini-scalpel was used for the incision and decompression of the nerve root sheath, in which a 3～5 mm longitudinal incision was made along the dorsal side of the nerve root. Results Decompression was achieved under microendoscope (MED-Ⅱ) in all the 39 patients. Limb numbness and radiculalgia subsided completely in 17 patients within 24 postoperative hours, while the symptoms trailed off within 2 weeks following the surgery in the remaining patients. The time to complete disappearance of the symptoms was 1～14 d (mean, 6 5 d). Conclusions Minimally invasive spinal nerve root sheath incision and decompression can give a prompt relief from limb numbness and radiculalgia, improving the recovery of nervous system. Lumbar spinal nerve root sheath incision and decompression under microendoscope (MED-Ⅱ) is a safe and effective procedure.

The Selective Spinal Nerve Root Block as Predictors of Outcome of Operative Treatment in the Lumbar Spine / 대한척추외과학회지

PURPOSE: The selective spinal nerve root block is one of the preoperative diagnostic tool to identify and confirm the lesion site of primary cause of pain. The purpose of this study was to ascertain the correlation between diagnostic selective spinal nerve root blocks and outcome following surgical treatment of selected levels of both lumbar herniated intervertebral disc (HIVD) and spinal stenosis. MATERIAL AND METHOD: In a total 341 selective nerve root blocks in 169 patients who were diagnosed as lumbar HIVD and spinal stenosis from Jan. 1993 to Jun. 1997 with performed in a retrospective study, two groups of patients were chosen for this study. The result of pain change of selective nerve root block were judged by Denis' pain scale, the end-result selective spinal nerve root and operative treatment used by Kim's criteria. RESULT : 1. The end-results of selective spinal nerve root block, excellent and good results were 64 cases (67.3%) in lumbar HIVD group and 50 cases (67.5%) in spinal stenosis group. The end-results of selective spine surgery, at last follow up, excellent and good results were 82 cases (86.2%) in lumbar HIVD group and 56 cases (75.7%) in spinal stenosis group. RESULT: 2. The predictive value of selective spinal nerve root block was 68.4% in lumbar HIVD group and 74.3% in spinal stenosis group. In addition, statistical analysis with regression analysis, to show any significant correlation between the selective spinal nerve root block results and the outcome of operative treatment, especially in spinal stenosis group. CONCLUSION: The selective spinal nerve root block is one of the valuable procedure that helpful and predictors of outcome selective operative treatment of lumbar spinal stenosis.

Change of the Intervertebral Foraminal Pressure after Removal of the Disc Material

OBJECTIVES: Spinal nerve root compression occurs commonly in conditions, such as herniated nucleus pulposus, spinal stenosis, intervertebral foraminal stenosis, and trauma. However, the pathophysiolosy of the symptoms and signs related to spinal nerve root compression is poorly understood. The purpose of the present study was to assess and compare the changes of various pressures of intervertebral foraminal pressure before and after decompression. METHOD: After laminetomy without foraminotomy was performed, pressure sensor tip of Camino parenchymal type was located at the middle-central portion of the intervertebral foramen and anterior portion of nerve root for the foraminal pressure before decompression of the intervertebral foramen. After laminectomy with foraminotomy, the same method was used for the foraminal pressure after decompression. The authors studied 40 consecutive patients (57 disc spaces) with severe constant root pain to the lower leg, pain unrelived by bed rest, and minimal tension signs, diagnosed by MRI. RESULTS: In patients with intervertebral foraminal stenosis, the intraforaminal pressure was decreased from 86+/-2.23mmHg to 17.1+/-1.51mmHg and in patients without stenosis, from 55.9+/-1.08mmHg to 11.9+/-1.25mmHg. All patients below 20mmHg after decompression showed good outcome, but 4 cases who showed poor outcome had foraminal stenosis, posterolateral type of the herniated disc, and above 30mmHg of foraminal pressure after decompression. CONCLUSION: These findings suggest that if the foraminal pressure falls below 20mmHg after decompression, good outcome can be anticipated. Central type of the herniated disc shows better outcome compared to the posterolateral type.

Selective Spinal Nerve Root Block for the Treatment of Sciatica / 대한정형외과학회잡지

The nerve root block or selective nerve root block is one of the primarily preoperative diagnostic tool to identify and confirm the lesion site of primary cause of pain and that is considered as one component of a comprehensive treatment program. The purpose of our study is to evaluate the effect and duration of the pain control by selective spinal nerve root block as a conservative treatment in patients presenting with chronic or recurrent sciatica. The authors performed 95 selective nerve root blocks in 72 patients from Sep. 1994 to May. 1996, (mean follow up 11.6 month) at the department of orthopedic surgery, Kosin University Gospel Hospital, and the results were as follows: 1. Among 72 cases, spinal stenosis was in 45 cases (62.5%), HIVD in 19 cases (26.4%), failed back syndrome in 5 cases (6.9%), spondylosis in 2 cases (2.8%), and spondylolisthesis in I case (1.4%). 2. In 72 cases, improved more than 50% of sciatica were 61 cases (84.7%) at 3 hours, 53 cases (73.6%) at I week, 35 cases (48.6%) at 1 month, 33 cases (45.8%) at 3 months, and 33 cases (45.8%) at 6 months respectively. 3. At last follow-up, excellent and good results were 35 cases (48.6%), fair results were 25 cases (34.7%) and poor results were 12 cases (16.7%) by the Kirkaldy-Willis criteria. 4. Complications were 1 case of transient hypotension, 2 cases of severe paresthesia, but subsided without residual complication. Therefore, the selective nerve root block is one of the valuable procedure that is helpful and extremely safe in useful treatment for radicular pain associated with lumbar disease. And the trial of selective nerve root block was recommended before deciding surgical intervention on an outpatient basis.

Effects of epidural capsaicin with different contrention on pain threshold and nerve tissue structure in rats / 中华麻醉学杂志

Objective To evaluate the effects of epidural capsaicin on pain threshold and nerve tissue structure in adult rats. Methods Twenty-four adult male Wistar rats weighing 250-300 g were used in this study. A catheter was inserted into epidural space at L5,6 according to the method of Philippe. 0.4 ml of capsaicin 0.1% (group A), 0.25% (group B) or 0.5% (group C) or 10% Tween 80 (control group) was injected via the epidural catheter. Pain threshold was measured by thermal stimulation of the tail before (baseline) and on the 3rd, 7th and 14th day after epidural capsaicin. The animals were then killed. The lumbar segment (L4-6) of the spinal cord and spinal nerve roots were removed immediately for light and electron microscopic examination. Results Pain threshold was significantly higher in group A, B and C than in control group (P

Effect of continuous spinal anesthesia with ropivacaine on the ultrastructuFe of spinal cord and nerve roots in rats / 中华麻醉学杂志

Objective To investigate the effects of continuous spinal anesthesia with different concentrations and doses of ropivacaine on the ultrastructure of the spinal cord and nerve roots. Methods Twenty-four male SD rats weighing 220-280 g were anesthetized with intraperitoneal 10% chloral hydrate 300-350 mg/kg. A polyurethane microcatheter was inserted into the lumbar subarachnoid space according to the technique described by Yaksh. An 8-cm catheter segment was left in the subarachnoid space. The animals were randomized to receive normal saline, 0.5%, 0.75% or 1.0% ropivacaine 40 ? 1 intrathecally 3 times at 1.5 h interval. Six hours after the first intrathecal administration the animals were decapitated and L1 ,2 segment of the spinal cord and nerve roots were immediately removed for electron microscopic examination. Results Electron microscopic examination revealed that in animals which received intrathecal (i.t.) normal saline, 0.5% or 0.75% ropivacaine the neurolemma of the nerve roots and the mitochondria and endoplasmic reticulum of the neurons in the spinal cord were intact, while in animals which received i.t. 1.0% ropivacaine the neurolemma was stratified and partly disrupted and there were swelling of endoplasmic reticulum and vacuole degeneration. Conclusion Six hours continuous spinal anesthesia with 1.0% ropivacaine may be injurious to the spinal cord and nerve roots.