Abstract: 2Department of Neurosurgery, Allegheny General Hospital, Pittsburgh, PA. ervical nerve root blocks have been performed since the late 19th century [1], and the use of the procedure has been increasing over the past decade [2]. Cervical nerve root blocks are used to manage or treat spinal pain, radiculopathy, and complex regional pain syndromes. Many such blocks are performed in outpatient clinics with and without imaging guidance such as fluoroscopy or CT. If imaging guidance is not used, palpable anatomic landmarks are generally used to direct needle placement. Various complications associated with the nerve block procedure have previously been described [3–7]. The most serious reported complications include death, stroke, arrhythmias, sensory or motor loss, meningitis, bleeding, and seizures. To our knowledge, arterial dissection has not previously been reported after a cervical selective nerve root block (SNRB). Our purpose is to present two cases that show potentially devastating outcomes when a cervical SNRB is performed using fluoroscopic guidance and to evaluate possible alternative methods currently available.

Abstract: Study design Assessment of activated T and B cells in a subcutaneous chamber filled with autologous nucleus pulposus using flow cytometry and immunohistochemistry. Objectives To examine if subcutaneously placed autologous nucleus pulposus may attract activated T and B cells in an animal model. Summary of background data Nucleus pulposus has been suggested to trigger an autoimmune response if exposed to the immune system, for example, in association with disc herniation. T-cell activation represents a hallmark in the generation of an autoimmune response, subsequently leading to the differentiation of B cells, but a causal association between the exposure of nucleus pulposus to the systemic circulation and T and B cell activation is still lacking. Methods Autologous nucleus pulposus was harvested from the intervertebral disc of 9 pigs and placed subcutaneously in perforated titanium chambers. In order to control for the effect of the titanium chamber, an additional empty chamber was placed subcutaneously in each pig. After 7 days, the pigs were killed and the chambers were harvested. Flow cytometry and immunohistochemistry were used for analysis of T-helper cells (CD4+), cytotoxic T cells (CD8+), and B cells (Igkappa) in the chamber exudates and T cells (CD45RC) in the remaining blood clot tissue of the chamber. Results As compared with the empty chambers, the proportion of activated T cells (CD4+ and CD8+) was significantly higher in the exudate of the nucleus pulposus filled chamber. The proportion of activated B cells expressing immunoglobulin kappa (Igkappa) was also significantly elevated in the exudate of the nucleus pulposus chambers. The analysis of the remaining chamber tissue revealed a significantly higher amount of T cells (CD45RC) in the nucleus pulposus chambers than in the empty chambers. Conclusions The present findings indicate that nucleus pulposus attracts activated T and B cells. However, since the cell population in the nucleus pulposus of young pigs may differ from that of adult humans, the obtained data may not be directly transferred to the human situation of a disc herniation. The observations in the present study may nevertheless explain some of the local tissue reactions occurring in association with disc herniation and nerve root involvement, thereby providing further insight into the pathophysiology of sciatica.

Abstract: Purpose To retrospectively determine the risks and benefits of contralateral C7 nerve root transfer in infants and children. Methods In 12 infants and children with brachial plexus root avulsions from birth injury or other trauma, the common trunk of the contralateral C7 root was transferred to the trunk, division, cord, or nerve branch(es) on the affected side with 2 different types of interposition grafts. The surgery was performed in 1 stage for 5 patients and in 2 stages for 7 patients. Results Patients were followed up for a mean of 42 months, with a minimum of 21 months. Noteworthy function (≥M2+, modified British Medical Research Council grading system) was gained in 10 of 12 patients and sensory function (≥S3, British Medical Research Council grading system) was gained in all patients. Improvements in strength and sensation were accompanied by little synchronous motion and sensibility changes in the donor limb in 7 children, to whom the repaired nerves were those innervating the shoulder and/or elbow or both the musculocutaneous and median nerves. In addition to slight damage to the sensory function of the median nerve, 2 infants also had temporarily reduced shoulder abduction on the healthy side. Conclusions For contralateral C7 transfer in infants and children with brachial plexus root avulsions, the deficit created by the procedure is minimal and motor and sensory function is gained. Transfer of the contralateral C7 root to different nerves for a child may improve the quality of functional recovery. Type of study/level of evidence Therapeutic, Level IV.

Abstract: This study investigated the maximum number of collaterals that can be maintained by 1 axon during regeneration of rat peripheral nerve. The tibial nerve was transected, the proximal residual, with its

Abstract: OBJECTIVE: The authors conducted a comparative study to analyze dosimetry and results to understand the significant difference in the rate of trigeminal dysfunction after gamma knife radiosurgery for trigeminal neuralgia between two centers using the same target. METHODS: The data of 358 patients (109 patients from Brussels and 259 patients from Marseilles) were analyzed. Three different dosimetric strategies were found: treatment with less than 90 Gy and no selective beam channel blocking (Group 1; patients from Marseilles only), treatment with 90 Gy and no selective beam channel blocking (Group 2; patients from Brussels and Marseilles), or treatment with 90 Gy and use of selective beam channel blocking (Group 3; patients from Brussels only). RESULTS: The prescription dose and the use of selective beam channel blocking have been significantly associated with a higher energy received by the retrogasserian trigeminal nerve root. The different radiation dose delivered to the nerve root in these three groups of patients was significantly associated with the incidence of mild (15, 21, and 49% for Groups 1, 2, and 3, respectively) and bothersome (1.4, 2.4, and 10% for Groups 1, 2, and 3, respectively) trigeminal dysfunction. The good and excellent rates of pain relief were 81 and 66%, respectively, for Group 1, 85 and 77%, respectively, for Group 2, and 90 and 84%, respectively, for Group 3, and were also related to the amount of energy received by nerve root volume. CONCLUSION: Using a similar target, the incidence of trigeminal dysfunction and the pain relief rate can vary according to the radiation energy received by the retrogasserian part of the trigeminal nerve root. The prescription dose and the use of beam channel blocking modify the integrated dose delivered to the nerve and may contribute to the different rates of trigeminal numbness and pain outcome. The radiobiological effect of gamma knife radiosurgery may be related to the energy delivered to nerve root volume, rather than to the maximal dose delivered.

Abstract: Study design Immunohistochemical and behavioral study using rat models of lumbar disc herniation and cauda equina syndrome. Objective To investigate the expression of activated p38 mitogen-activated protein kinases (p38 MAP kinase; p38) in the spinal cord and to determine the effect of intrathecal administration of a specific p38 inhibitor on pain in a lumbar disc herniation model and on motor function and hypoalgesia in a spinal canal stenosis (SCS) model. Summary of background data In pathologic lumbar disc herniation-induced neuropathic pain and compression of cauda equina-induced motor dysfunction and hypoalgesia caused by SCS, glia are activated and produce certain cytokines, including tumor necrosis factor-alpha (TNF-alpha) and interleukins, which play a crucial role in the pathogenesis of nerve degeneration. p38 is phosphorylated by these cytokines, suggesting that it may play an important role in pain transmission and nerve degeneration. Here we have examined the role of p38 in rat models of lumbar disc herniation and SCS. Methods Six-week-old male Sprague-Dawley rats were used. For the disc herniation model, autologous nucleus pulposus was applied to L5 nerve roots, which were then crushed. For the SCS model, a piece of silicon was placed under the lamina of the fourth lumbar vertebra. We assessed mechanical allodynia, hypoalgesia, and motor function using von Frey hairs, treadmill tests, and immunohistochemical localization of phosphorylated p38 (P-p38) in the cauda equina, dorsal root ganglion (DRG), and spinal cord, which were also double-stained with NeuN (neuronal marker), GFAP (astrocyte/Schwann cell marker), or isolectin B4 (IB4; microglia marker). We also examined the effects of intrathecal administration of a specific p38 inhibitor, FR167653, on nucleus pulposus-induced pain, hypoalgesia, and motor dysfunction following SCS. Results We demonstrated that activated P-p38-immunoreactive cells in the spinal cord and cauda equina were not observed before nerve injury but appeared in the cauda equina, DRG, and spinal dorsal horn in the disc herniation and SCS models. Double-labeling revealed that most P-p38-immunoreactive cells were isolectin B4-labeled microglia and GFAP-immunoreactive Schwann cells. Intrathecal administration of the p38 inhibitor FR167653 decreased mechanical allodynia in the disc herniation model and improved hypoalgesia and intermittent motor dysfunction in the SCS model. Conclusions Our findings suggest that activated p38 may play an important role in the involvement of microglia in the pathophysiology of pain following lumbar disc herniation and mechanical hypoalgesia, and motor nerve dysfunction of cauda equina following SCS.

Abstract: Selective nerve root blocks or transforaminal epidural injections are used for diagnosis and treatment of different spinal disorders. A clear consensus on the use of selective nerve root injections as a diagnostic tool does not currently exist. Additionally, the effectiveness of this procedure as a diagnostic tool is not clear. A systematic review of diagnostic utility of selective nerve root blocks was performed and published in January 2005, which concluded that selective nerve root injections may be helpful as a diagnostic tool in evaluating spinal pain with radicular features, but its role needs to be further clarified.

Abstract: Study design An experimental animal study. Objective To study if antitumor necrosis factor-alpha (TNF-alpha) antibody, which is administered at different times, reduces the pain behavior induced by application of nucleus pulposus (NP) to the nerve root. Summary of background data Treatment with TNF-alpha inhibitor reduces the pain-related behavior induced by epidural application of NP in rats. Methods Left L5 partial laminectomy was performed and NP was applied to the L5 nerve root in 24 rats. The rats were divided into 4 groups. In 3 groups, anti-rat TNF-alpha antibody was intravenously administered immediately after, or 6 or 20 days after NP application. The fourth group was not treated with anti-rat TNF-alpha antibody (untreated rats). The withdrawal threshold of the plantar surface was determined 1 day before up through 28 days after NP application. Results The withdrawal threshold of rats that had been treated with anti-rat TNF-alpha antibody immediately after or 6 days after, but not 20 days after, NP application, was significantly higher than that of the untreated rats. Conclusions Anti-TNF-alpha antibody reduced allodynia only when it was administered soon after the onset of allodynia. Late administration of anti-TNF-alpha antibody did not have an antiallodynic effect.

Abstract: Study design The association between lumbar facet joint inflammation and radiculopathy was investigated using behavioral, histologic, and immunohistochemical testing in rats. Objectives To develop a rat model of lumbar facet joint inflammation and ascertain whether facet joint inflammation induces radiculopathy using this model. Summary of background data Both mechanical and chemical factors have been identified as important for inducing radiculopathy. In lumbar spondylosis, facet joint osteophytes may contribute to nerve root compression, which may induce radiculopathy. Furthermore, inflammation may occur in the facet joint, as in other synovial joints. Inflamed synovium may thus release inflammatory cytokines and induce nerve root injury with subsequent radiculopathy. Methods A piece of gelatin sponge containing complete adjuvant was inserted into the L5-L6 facet joint in rats (arthritis group). Saline was used in the control group. Mechanical allodynia was determined using the von Frey test. Inflammatory cells infiltrating the epidural space were counted, and changes in cartilage were assessed histologically. Tumor necrosis factor (TNF)-alpha-immunoreactive cells in the L5 dorsal root ganglion were counted. Results Mechanical allodynia was observed in the arthritis group from day 3, gradually recovering during the observation period. Significantly larger numbers of inflammatory cells had infiltrated the epidural space by days 3 and 7 in the arthritis group than in controls. Numbers of TNF-alpha-immunoreactive cells were significantly increased at days 1 and 3 in the arthritis group compared with controls. Predominantly small nociceptive neurons were stained. Conclusions When inflammation was induced in a facet joint, inflammatory reactions spread to nerve roots, and leg symptoms were induced by chemical factors. These results support the possibility that facet joint inflammation induces radiculopathy.

Abstract: Study design A descriptive cadaveric study incorporating a novel nerve root marking technique. Objectives To describe the displacement and strain of the lumbosacral nerve roots in the lateral recess during straight leg raise (SLR) without disrupting the foraminal ligaments. Summary of background data Previous studies document 2 to 8 mm of lumbosacral nerve root displacement during SLR. Prior dissection methods incorporated laminectomy and facetectomy. Methods Lower limbs and associated nerve roots of 5 unembalmed cadavers (n = 10) were studied. Metal markers were inserted intraneurally within the lateral recess of L4, L5, and S1 with a modified spinal needle. Fluoroscopic images were digitized to evaluate displacement and strain during SLR. Results The lumbosacral nerve roots in the lateral recess moved less and experienced less strain during SLR than described in previously published reports. Statistically significant distal displacement occurred at hip positions greater than 60 degrees of flexion at all nerve root levels (P Conclusions The lumbosacral nerve roots (L4, L5, S1) moved less and underwent less strain during SLR testing than previously reported and may require hip motion greater than 60 degrees to produce substantive displacement in the lateral recess. Additional research is needed to examine the effects of prepositioning during SLR.

Abstract: Since many years we routinely use diagnostic selective nerve root blocks (SNRB) at our department when evaluating patients with cervical radiculopathy. Frequently patients who also presented with headache reported that the headache disappeared when the nerve root responsible for the radicular pain was blocked with local anaesthetics. Headache has been described as a companioning symptom related to cervical radiculopathy but has never before been evaluated with SNRB performed in the lower cervical spine. For this reason we added to our routine an evaluation of the response from the SNRB on headache in patients with cervical radiculopathy. The aim was to describe the frequency of headache in patients with cervical radiculopathy and its response to a selective nerve root block of the nerve root/roots responsible for the radiculopathy. Can nerve root compression in the lower cervical spine produce headache? In this consecutive series of 275 patients with cervical radiculopathy, 161 patients reported that they also suffered from daily or recurrent headache located most often unilaterally on the same side as the radiculopathy. All patients underwent a careful clinical examination by a neurosurgeon and a MRI of the cervical spine. The significantly compressed root/roots, according to the MRI, underwent SNRB with a local anaesthetic. The effect of the nerve root block on the radiculopathy and the headache was carefully noted and evaluated by a physiotherapist using visual analogue scales (VAS) before and after the SNRB. All patients with headache had tender points in the neck/shoulder region on the affected side. Patients with headache graded significantly more limitations in daily activities and higher pain intensity in the neck/shoulder/arm than patients without headache. After selective nerve root block, 59% of the patients with headache reported 50% or more reduction of headache and of these 69% reported total relief. A significant correlation was seen between reduced headache intensity and reduced pain in the neck, shoulder and arm. The result indicates that cervical root compression from degenerative disease in the lower cervical spine producing radiculopathy might also induce headache.

Abstract: Benign peripheral nerve lesions of lipomatous, vascular, and chondromatous origin are very rare. Only one previous case of brachial plexus involvement by such a tumor has been reported. The authors report on their experience with peripheral nerve tumors in three patients and review the available literature on these topics. The three cases discussed include a 44-year-old woman with an intraneural lipoma of the right middle trunk, a 40-year-old woman with an intraneural hemangioma infiltrating the right posterior cord, and a newborn male with a predominantly cartilaginous hamartoma originating from the right C-5 nerve root. The literature review yielded six previous cases of intraneural lipoma, approximately 50 cases of lipofibromatous hamartoma, 13 cases of intraneural hemangioma, and no previous case of cartilaginous hamartoma originating from a nerve. Intraneural lipomas are well encapsulated, and gross-total resection can be achieved. Lipofibromatous hamartomas are diffusely infiltrative; decompressive debulking and neurolysis is often the most appropriate initial approach for patients with symptomatic lesions. Resection of intraneural hemangiomas can be achieved but may require nerve resection and repair in some cases. Debulking has been reported to provide prolonged symptomatic relief in these lesions, and preoperative embolization and postoperative radiotherapy were beneficial in the case presented here. To the authors' knowledge, this is the first reported case of a cartilaginous hamartoma infiltrating a peripheral nerve. Gross-total resection of symptomatic intraneural lipomas is feasible and apparently curative. The optimal treatment for lipofibromatous hamartomas and vascular and chondromatous lesions of the peripheral nerves is uncertain and should be guided by the severity of symptoms.

Abstract: BACKGROUND Neurovascular conflict is regarded as the most common cause of idiopathic trigeminal neuralgia. It is suspected that a blood vessel in contact with the root entry zone of a trigeminal nerve causes its irritation. The aim of the study was to evaluate how signs of neurovascular conflict can be found in people without trigeminal neuralgia MATERIAL/METHODS The study was conducted retrospectively. The authors analyzed MR examinations of 60 patients (120 nerves), aged 22-77 years, who did not have trigeminal neuralgia or related symptoms. Nerve-artery contact at the root entry zone of a trigeminal nerve, nerve deformation, and atrophy were searched for in angio-3D-TOF images (slice thickness: 1 mm). RESULTS Contact between a trigeminal nerve and an artery was found in 30 cases (25% of nerves). The blood vessel was parallel to the nerve root in 14 cases (11.7%) and crossed it at a right or acute angle in 15 cases (12.5%). Contact between artery and atrophic nerve was found in one case. Modeling of the trigeminal nerve by an artery was not found. CONCLUSIONS Contact between a trigeminal nerve root and an artery in the prepontine cistern is a frequently seen anatomical variant. Therefore, detection of such a variant is not equivalent to finding the cause of a patient's complaints.

Abstract: Discrepancies abound in the literature regarding the anatomy and incidence of the C1 dorsal roots, ganglia, and rami. The present study was performed to elucidate further the detailed anatomy of these structures and to review their clinical relevance. Thirty-adult cadavers were used for this study. The mean age for this group was 72 years. C1 and C2 spinal nerves were identified in 100% of the specimens examined. In 46.6% of specimens, C1 dorsal rootlets were identified and of these, 28.5% had an associated dorsal root ganglion. In 50% of specimens, the spinal accessory nerve joined with dorsal rootlets of C1. C1 in these cases did not possess a dorsal root ganglion. There were no significant differences between left sides, gender, and age (P > 0.05). Additional knowledge regarding the C1 dorsal roots, ganglia, and rami may be of use to the clinician who treats various pain syndromes including medically and surgically intractable occipital neuralgia.

Abstract: We have recently shown in experimental nerve injury models that nerve regeneration is enhanced across a motor nerve graft as compared with a sensory nerve graft. To test the hypothesis that nerve architecture may mediate the beneficial effect of motor nerve grafting, we developed a model of disrupted nerve architecture in which motor and sensory nerve fragments were introduced into silicone conduits. Lewis rats were randomized to 5 experimental groups: nerve repair with motor nerve fragments, sensory nerve fragments, mixed nerve fragments, saline-filled conduit (negative control), or nerve isograft (positive control). At 6, 9, or 12 weeks, animals were sacrificed and nerve tissues were analyzed by quantitative histomorphometry. No significant differences were observed between the motor, sensory, and mixed nerve fragment groups. These findings suggest that intact nerve architecture, regardless of neurotrophic or biochemical factors, is a prerequisite for the beneficial effect of motor nerve grafting.

Abstract: A method for altering operation of a nerve related to a given body condition includes the steps of identifying at least one nerve root of a nerve related to the given body condition; laparoscopically implanting at least one electrode on the nerve root; and operating the electrode to electrostimulate the nerve root and alter operation of the nerve

Abstract: PURPOSE: Spinal root avulsions result in paralysis of the upper and/or lower extremities. Implanting a peripheral nerve bridge or reinsertion of the avulsed roots in the spinal cord are surgical strategies that lead to some degree of functional recovery. In the current study lentiviral (LV) vector-mediated gene transfer of a green fluorescent protein (GFP) reporter gene was used to study the feasibility of gene therapy in the reimplanted root to further promote regeneration of motor axons. METHODS: A total of 68 female Wistar rats underwent unilateral root avulsion of the L4, L5 and L6 ventral lumbar roots. From 23 rats intercostal nerves were dissected before ventral root avulsion surgery, injected with a lentiviral vector encoding GFP (LV-GFP) and inserted between the spinal cord and avulsed rootlet. In the remaining 45 rats, the avulsed ventral root was injected with either LV-GFP or a lentiviral vector encoding a fusion between a GlyAla repeat and GFP (LV-GArGFP), and reinserted into the spinal cord. Expression of GFP was evaluated at 1,2, 4 and 10 weeks, and one group at 4 months. RESULTS: LV-GFP transduction of either nerve implants or reimplanted ventral roots revealed high GFP expression during the first 2 post-lesion weeks, but virtually no expression at 4 weeks. Since this reduction coincided with the appearance of mononuclear cells at the repair site, an immune response against GFP may have occurred. In a subsequent experiment reimplanted ventral roots were transduced with a vector encoding GFP fused with the GlyAla repeat of Epstein-Barr virus Nuclear Antigen 1 known to prevent generation of antigenic peptides from transgene products. Expression of this "stealth" gene persisted for at least 4 months in the reimplanted root. CONCLUSION: Thus persistent transgene expression can be achieved with non-immunogenic transgene products in reimplanted ventral roots. This demonstrates the feasibility of combining neurosurgical repair with LV vector-mediated gene therapy. The current approach will be used in future experiments with LV vectors encoding neurotrophic factors to enhance the regeneration of spinal motor neurons after traumatic avulsion of spinal nerve roots.

Abstract: Perineural cysts have become a common incidental finding during lumbosacral magnetic resonance (MR) imaging. Only some of the symptomatic cysts warrant treatment. The authors describe the successful operative treatment of a patient with, to the best of their knowledge, the largest perineural cyst reported to date. A 29-year-old woman had been suffering from long-standing constipation and low-back pain. During an obstetric investigation for infertility, the clinician discovered a huge presacral cystic mass. Computed tomography myelography showed the lesion to be a huge Tarlov cyst arising from the left S-3 nerve root and compressing the ipsilateral S-2 nerve. The cyst was successfully treated by ligation of the cyst neck together with sectioning of the S-3 nerve root. Postoperative improvement in her symptoms and MR imaging findings were noted. Identification of the nerve root involved by the cyst wall, operative indication, operative procedure, and treatment of multiple cysts are important preoperative considerations.

Abstract: Gene transfer to a transected peripheral nerve or avulsed nerve root is discussed to be helpful where neurosurgical peripheral nerve reconstruction alone will not result in full recovery of function. Axonal regeneration is supposed to be facilitated by this new therapeutic approach via delivery of specific regeneration promoting molecules as well as survival proteins for the injured sensory and motor neurons. Therefore gene therapy aims in long-term and site-specific delivery of those neurotrophic factors. This paper reviews methods and perspectives for gene therapy to promote functional recovery of severely injured and thereafter reconstructed peripheral nerves. Experimental in vivo and ex vivo gene therapy approaches are reported by different groups. In vivo gene therapy generally uses direct injection of cDNA vectors to injured peripheral nerves. Ex vivo gene therapy is based on the isolation of autologous cells followed by genetic modification of these cells in vitro and re-transplantation of the modified cells to the patient as part of tissue engineered nerve transplants. Vectors of different origin are published to be suitable for peripheral nerve gene therapy and this review discusses the different strategies with regard to their efficiency in gene transfer, their risks and their potential relevance for clinical application.

Abstract: Dorsal root injury is known to induce alteration of the extracellular environment in the spinal cord and synaptic reorganization with degradation of injured primary afferent and sprouting of spared terminal. These changes affect behavioral sensitivity and sometimes lead to neuropathic pain. We have hypothesized that changes in extracellular proteolysis in the dorsal horn is involved in neuroplastic changes in the dorsal horn after nerve injury. Tissue type plasminogen activator (tPA) is a well-known extracellular serine protease and is involved in the modification of the extracellular matrix, which leads to neuroplastic changes such as long-term potentiation in the hippocampus. In the present study, we found a marked induction of tPA in activated astrocytes following L4/5 root injury and a resultant increase of proteolytic enzymatic activity in the dorsal horn. We also examined the involvement of tPA activity on mechanical hypersensitivity using a root ligation model which has been used for investigating radiculopathy pain behavior. Intrathecal and continuous administration of tPA inhibitor, tPA-STOP, suppressed root ligation-induced mechanical allodynia in a dose-dependent manner during an early stage of injury (0-4 days). In contrast, the delayed administration of tPA-STOP during the chronic stage of injury (10 days) did not affect pain behavior. These data suggest an important contribution of astrocytes in the dorsal horn to the pathophysiology of radiculopathy pain, and astrocyte-derived tPA and the proteolytic activity in the dorsal horn may be one of the essential factors involved in pain following root injury.

Abstract: Objective Spinal extramedullary hematomas stemming from cavernous angiomas in the epidural compartment are rare. It is more common for spinal epidural cavernous angiomas to present with slow and progressive myelopathy or radiculopathy. They seldom present with clinical evidence of acute spinal cord or nerve root compression. Clinical presentation Three consecutive cases of acute spinal cavernous angiomas with overt neurological deficits were presented. These presentations included acute onset of neck pain and tetraparesis, bilateral lower extremity pain and paraparesis, and acute sciatic pain with plantar flexor weakness. The lesions were located in the cervical, thoracic, and sacral spine, respectively. The cases included either abrupt lesion enlargement secondary to a pure intralesional hemorrhage or a cavernous hemorrhage that invaded the epidural space. Intervention All patients were treated with either laminotomy or complete resection of the hematoma and cavernoma within 12 hours after admission. Conclusion Spontaneous spinal epidural hematomas presented with significant pain and acute spinal cord and nerve root compression may represent the manifestation of a cavernous angioma. Appropriate interpretation of preoperative imaging studies may prevent delay in proper management, especially for patients in whom nerve root deficit is the only clinical expression.

Abstract: The aim of this study was to evaluate three-dimensional Fourier transformation-constructive interference in steady-state (CISS) imaging as a preoperative anatomical evaluation of the relationship between the placode, spinal nerve roots, CSF space, and the myelomeningocele sac in neonates with lumbosacral myeloschisis Five consecutive patients with lumbosacral myeloschisis were included in this study Magnetic resonance (MR) CISS, conventional T1-weighted (T1-W) and T2-weighted (T2-W) images were acquired on the day of birth to compare the anatomical findings with each sequence We also performed curvilinear reconstruction of the CISS images, which can be reconstructed along the curved spinal cord and neural placode Neural placodes were demonstrated in two patients on T1-W images and in three patients on T2-W images T2-W images revealed a small number of nerve roots in two patients, while no nerve roots were demonstrated on T1-W images In contrast, CISS images clearly demonstrated neural placodes and spinal nerve roots in four patients These findings were in accordance with intraoperative findings Curvilinear CISS images demonstrated the neuroanatomy around the myeloschisis in one slice The resulting images were degraded by a band artifact that obstructed fine anatomical analysis of the nerve roots in the ventral CSF space The placode and nerve roots could not be visualized in one patient in whom the CSF space was narrow due to the collapse of the myelomeningocele sac MR CISS imaging is superior to T1-W and T2-W imaging for demonstrating the neural placode and nerve roots, although problems remain in terms of artifacts

Abstract: The objective of the study was to assess the long-term efficacy of fluoroscopically-guided cervical nerve root block as a non-surgical treatment for cervical radicular pain. This was a retrospective study of 19 consecutive patients who had undergone cervical nerve root blocks over a period of 18 months, at a regional neurosurgery referral centre in the UK. Two of these patients underwent a second procedure; therefore, the number of total nerve root blocks was 21. Data regarding age, sex and diagnosis were obtained from medical records. MR reports formed the basis for imaging findings. Patients were contacted by telephone and post in order to obtain information about their 'pain relief. This was measured by using a 100-point Visual Analogue Scale (VAS). Four points in time were chosen in order to determine the time course of pain relief, i.e. before procedure, at 2 weeks, at 2 months and at 6 months following the procedure. Mean VAS scores at 6 month follow-up were broken up into 3 categories to indicate the level of pain relief. These categories were: VAS decrease of less than 20 points indicating no relief (12 procedures, 57.1%); VAS decrease 20 - 40 points, i.e. moderate relief (three procedures, 14.3%); VAS decrease of greater than 40 points, i.e. significant relief (six procedures, 28.6%). CNRB has limited efficacy for definitive treatment of nerve root pain, but may lead to significant short term relief, in a subgroup of such patients.

Abstract: Study design Case series. Objective Presentation of results of dorsal root entry zone lesions in 10 patients suffering from severe neuropathic pain due to brachial plexopathy or radiation-induced trigeminal neuropathy. Summary of background data Radiation-induced neuropathy is an uncommon but serious complication of radiotherapy. It may cause delayed motor and sensitive impairment associated with severe treatment-resistant pain. Various therapeutic approaches have been reported aimed at controlling radiation-induced neuropathy-pain, demonstrating poor outcomes. Methods Eight patients with plexopathy underwent dorsal root entry zone lesion in the cervical spinal cord, while 2 other subjects received stereotactic trigeminal nucleotractotomy. Subjects were followed prospectively before and after brachial dorsal root entry zone or trigeminal caudal operations (range 0.5-36 months). Results All patients experienced improvement in pain conditions. A total of 8 patients reported full pain relief (visual analog scale = 0) by the end of the follow-up period. The remaining patients had partial control of pain. One patient required reoperation to achieve optimal pain relief. Both patients who underwent trigeminal nucleotractotomy had transient ataxia in the ipsilateral upper limb. One of the patients treated by dorsal root entry zone lesion had minor aggravation of weakness of the ipsilateral lower limb. Conclusion The present results suggest that the trigeminal nucleotractotomy and dorsal root entry zone lesions in cervical spinal cord are an effective procedure for the treatment of pain associated with actinic peripheral neuropathy.

Abstract: We present a case of a pelvic ring fracture that was originally treated with anterior symphyseal plating and a misplaced percutaneous iliosacral screw. The anterior extraosseus portion of the misplaced 7.3-mm cannulated screw irritated the L5 nerve root, resulting in a radiculopathy. Subsequent surgery involved and mandated removing the bent screw after open identification and protection of the L5 nerve root to avoid further nerve damage; the sacroiliac joint was subsequently debrided and fused. This case represents a complication of acute percutaneous iliosacral screw fixation of pelvic ring injuries and the subsequent strategy for successful salvage.

Abstract: Peripheral nervous system (PNS) affection is an uncommon, sometimes life-threatening manifestation of giant cell arteritis (GCA). To describe characteristics of neurological abnormalities of the PNS in GCA patients. Eighty consecutive cases of biopsy proven GCA were studied. Three patients presented with subacute sensorimotor deficits abnormalities in the distribution of the arm plexus. In all cases PNS affection was the leading clinical symptom in addition to a typical clinical syndrome of cranial arteriitis. In one case MRI demonstrated diffuse signal abnormalities surrounding the brachial nerve plexus. In another patient, who died from pulmonary embolism 10 weeks after beginning of therapy, autopsy demonstrated residual arteritis in an artery supplying the brachial nerve plexus. Involvement of the PNS is more uncommon than cerebral ischemia and neuroophthalmological complications in patients suffering from GCA. Severe PNS involvement has an affinity to the midcervical nerve roots and the brachial nerve plexus.