Sex-specific alterations in functional connectivity and network topology in patients with degenerative cervical myelopathy.

Patients with degenerative cervical myelopathy (DCM) experience structural and functional brain reorganization. However, few studies have investigated the influence of sex on cerebral alterations. The present study investigates the role of sex on brain functional connectivity (FC) and global network topology in DCM and healthy controls (HCs). The resting-state functional MRI data was acquired for 100 patients (58 males vs. 42 females). ROI-to-ROI FC and network topological features were characterized for each patient and HC. Group differences in FC and network topological features were examined. Compared to healthy counterparts, DCM males exhibited higher FC between vision-related brain regions, and cerebellum, brainstem, and thalamus, but lower FC between the intracalcarine cortex and frontal and somatosensory cortices, while DCM females demonstrated higher FC between the thalamus and cerebellar and sensorimotor regions, but lower FC between sensorimotor and visual regions. DCM males displayed higher FC within the cerebellum and between the posterior cingulate cortex (PCC) and vision-related regions, while DCM females displayed higher FC between frontal regions and the PCC, cerebellum, and visual regions. Additionally, DCM males displayed significantly greater intra-network connectivity and efficiency compared to healthy counterparts. Results from the present study imply sex-specific supraspinal functional alterations occur in patients with DCM.

Pure epidural extraosseous cavernous hemangioma with thoracic myelopathy: case report and review of literature.

INTRODUCTION: Pure epidural spinal cavernous hemangiomas are rare, benign vascular tumors that account for approximately 4% of all spinal epidural tumors. Due to their dumbbell shape and propensity for foraminal invasion, they are often misdiagnosed and inadequately treated. We present a case of a 58-year-old male with extra-osseous cavernous hemangioma to better aid in diagnosis and management of these lesions. CASE PRESENTATION: A 58-year-old male presented with chronic lower back pain, progressive lower extremity weakness, T10 sensory level, absent lower extremity proprioception, hyperreflexia, and an episode of bowel incontinence. Imaging demonstrated T7-T10 homogenous dorsal epidural mass causing cord signal change. He underwent resection with histopathologic exam revealing a pure epidural cavernous hemangioma. CONCLUSION: Spinal epidural cavernous hemangiomas are exceedingly rare lesions that are often misdiagnosed as nerve sheath tumors and meningiomas. Common features include chronic pain and myelopathy as well as T1 isodensity, T2 hyperintensity, and homogenous enhancement. Uniquely, they present as a lobulated, spindled shape with tapered ends in the dorsal epidural space. Both gross and subtotal resection result in favorable neurologic outcomes.

Preliminarily exploring the intraoperative ultrasonography characteristics of patients with degenerative cervical myelopathy.

BACKGROUND: How to quickly read and interpret intraoperative ultrasound (IOUS) images of patients with degenerative cervical myelopathy (DCM) to obtain meaningful information? Few studies have systematically explored this topic. PURPOSE: To systematically and comprehensively explore the IOUS characteristics of patients with DCM. MATERIALS AND METHODS: This single-center study retrospectively included patients with DCM who underwent French-door laminoplasty (FDL) with IOUS guidance from October 2019 to March 2022. One-way ANOVA and Pearson's /Spearman's correlation analysis were used to analyze the correlations between the cross-sectional area of the spinal cord (SC) and individual characteristics; the relationships between the morphology, echogenicity, pulsation, decompression statuses, compression types of SC, location of the spinal cord central echo complex (SCCEC) and the disease severity (the preoperative Japanese Orthopedic Association score, preJOA score); the difference of the spinal cord pulsation amplitude(SCPA) and the SCCEC forward movement rate (FMR) between the compressed areas(CAs) and the non-compressed areas (NCAs). RESULTS: A total of 38 patients were successfully enrolled (30 males and 8 females), and the mean age was 57.05 ± 10.29 (27-75) years. The cross-sectional area of the SC was negatively correlated with age (r = - 0.441, p = 0.006). The preJOA score was significantly lower in the heterogeneous group than in the homogeneous group (P < 0.05, p = 0.005). The hyperechoic area (HEA) was negatively while the SCCEC FMR was positively correlated with the preJOA score (r = - 0.334, p = 0.020; r = 0.286, p = 0.041). The SCCEC FMR and SCPA in CAs were significantly greater than those in NCAs (p < 0.05, p = 0.007; P < 0.001, P = 0.000). CONCLUSION: The cross-sectional area of the SC decreases with age in adults. More changes in intramedullary echogenicity and less moving forward of the SCCEC often indicate poor SC status, and the SCCEC FMR and SCPA are more pronounced in CAs.

Unilateral biportal endoscopic decompression versus anterior cervical decompression and fusion for unilateral cervical radiculopathy or coexisting cervical myelopathy: a prospective, randomized, controlled, noninferiority trial.

BACKGROUND: Cervical spondylosis (CS), including myelopathy and radiculopathy, is the most common degenerative cervical spine disease. This study aims to evaluate the clinical outcomes of unilateral biportal endoscopy (UBE) compared to those of conventional anterior cervical decompression and fusion (ACDF) for treating unilateral cervical radiculopathy or coexisting cervical myelopathy induced by unilateral cervical herniated discs. METHODS: A prospective, randomized, controlled, noninferiority trial was conducted. The sample consisted of 131 patients who underwent UBE or ACDF was conducted between September 2021 and September 2022. Patients with cervical nerve roots or coexisting spinal cord compression symptoms and imaging-defined unilateral cervical radiculopathy or coexisting cervical myelopathy induced by unilateral cervical herniated discs were randomized into two groups: a UBE group (n = 63) and an ACDF group (n = 68). The operative time, blood loss, length of hospital stay after surgery, and perioperative complications were recorded. Preoperative and postoperative modified Japanese Orthopaedic Association (mJOA) scale scores, visual analog scale (VAS) scores, neck disability index (NDI) scores, and recovery rate (RR) of the mJOA were utilized to evaluate clinical outcomes. RESULTS: The hospital stay after surgery was significantly shorter in patients treated with UBE than in those treated with ACDF (p < 0.05). There were no significant differences in the neck or arm VAS score, NDI score, mJOA score, or mean RR of the mJOA between the two groups (p < 0.05). Only mild complications were observed in both groups, with no significant difference (p = 0.30). CONCLUSION: UBE can significantly relieve pain and disability without severe complications, and most patients are satisfied with this technique. Consequently, this procedure can be used safely and effectively as an alternative to ACDF for treating unilateral cervical radiculopathy or coexisting cervical myelopathy induced by unilateral cervical herniated discs. TRIAL REGISTRATION: This study was registered in the Chinese Clinical Trial Registry on 02/08/2023 ( http://www.chictr.org.cn , #ChiCTR2300074273).

Nitrous oxide myelopathy: a case series.

AIMS: To describe the clinical features and outcomes of patients with myelopathy and neuropathy due to recreationally inhaled nitrous oxide. METHODS: We identified patients presenting with nitrous oxide-associated myelopathy from an electronic database of all discharges in a large tertiary hospital between 2016 and 2023. Demographics, clinical features and the results of investigations were recorded. The primary outcome was modified Rankin Scale score (mRS) at least 3 months after hospital discharge where available. RESULTS: There were 12 patients identified, six women, mean (SD) age 27.5 (5.1) years, range 19-47 years. The most common symptoms were numbness, weakness and mental state changes. Four patients used large amounts of inhaled nitrous oxide and also took over-the-counter vitamin B12 supplements. The median (range) hospital length of stay was 8.5 (2-56) days. Functional independence at last assessment (median [range] of 3 [1-34] months after discharge) was achieved in nine of the patients, with three requiring ongoing support for activities of daily living (mRS ≥3). CONCLUSION: Nitrous oxide abuse and its neurological complications are an important public health issue. Clinicians should be aware that some patients who use large amounts of nitrous oxide may self-supplement vitamin B12.

Resting-state brain plasticity is associated with the severity in cervical spondylotic myelopathy.

OBJECTIVE: To investigate the brain mechanism of non-correspondence between imaging presentations and clinical symptoms in cervical spondylotic myelopathy (CSM) patients and to test the utility of brain imaging biomarkers for predicting prognosis of CSM. METHODS: Forty patients with CSM (22 mild-moderate CSM, 18 severe CSM) and 25 healthy controls (HCs) were recruited for rs-fMRI and cervical spinal cord diffusion tensor imaging (DTI) scans. DTI at the spinal cord (level C2/3) with fractional anisotropy (FA) and degree centrality (DC) were recorded. Then one-way analysis of covariance (ANCOVA) was conducted to detect the group differences in the DC and FA values across the three groups. Pearson correlation analysis was then separately performed between JOA with FA and DC. RESULTS: Among them, degree centrality value of left middle temporal gyrus exhibited a progressive increase in CSM groups compared with HCs, the DC value in severe CSM group was higher compared with mild-moderate CSM group. (P < 0.05), and the DC values of the right superior temporal gyrus and precuneus showed a decrease after increase. Among them, DC values in the area of precuneus in severe CSM group were significantly lower than those in mild-moderate CSM and HCs. (P < 0.05). The fractional anisotropy (FA) values of the level C2/3 showed a progressive decrease in different clinical stages, that severe CSM group was the lowest, significantly lower than those in mild-moderate CSM and HCs (P < 0.05). There was negative correlation between DC value of left middle temporal gyrus and JOA scores (P < 0.001), and the FA values of dorsal column in the level C2/3 positively correlated with the JOA scores (P < 0.001). CONCLUSION: Structural and functional changes have taken place in the cervical spinal cord and brain of CSM patients. The Brain reorganization plays an important role in maintaining the symptoms and signs of CSM, aberrant DC values in the left middle temporal gyrus may be the possible mechanism of inconsistency between imaging findings and clinical symptoms. Degree centrality is a potentially useful prognostic functional biomarker in cervical spondylotic myelopathy.

Would the one-stage combined approach lead to better long-term neurological outcomes than the posterior approach alone in multilevel degenerative cervical myelopathy patients with T2-Weighted increased signal intensity? An 8-year follow-up results and propensity score matching analysis.

BACKGROUND: T2-weighted increased signal intensity (ISI) is commonly recognized as a sign of more severe spinal cord lesions, usually accompanied by worse neurological deficits and possibly worse postoperative neurological recovery. The combined approach could achieve better decompression and better neurological recovery for multilevel degenerative cervical myelopathy (MDCM). The choice of surgical approach for MDCM with intramedullary T2-weighted ISI remains disputed. This study aimed to compare the neurological outcomes of posterior and one-stage combined posteroanterior approaches for MDCM with T2-weighted ISI. METHODS: A total of 83 consecutive MDCM patients with confirmed ISI with at least three intervertebral segments operated between 2012 and 2014 were retrospectively enrolled. Preoperative demographic, radiological and clinical condition variables were collected, and neurological conditions were evaluated by the Japanese Orthopedic Assessment score (JOA) and Neck Disability Index (NDI). Propensity score matching analysis was conducted to produce pairs of patients with comparable preoperative conditions from the posterior-alone and combined groups. Both short-term and mid-term surgical outcomes were evaluated, including the JOA recovery rate (JOARR), NDI improvements, complications, and reoperations. RESULTS: A total of 83 patients were enrolled, of which 38 and 45 patients underwent posterior surgery alone and one-stage posteroanterior surgery, respectively. After propensity score matching, 38 pairs of comparable patients from the posterior and combined groups were matched. The matched groups presented similar preoperative clinical and radiological features and the mean follow-up duration were 111.6 ± 8.9 months. The preoperative JOA scores of the posterior and combined groups were 11.5 ± 2.2 and 11.1 ± 2.3, respectively (p = 0.613). The combined group presented with prolonged surgery duration(108.8 ± 28.0 and 186.1 ± 47.3 min, p = 0.028) and greater blood loss(276.3 ± 139.1 and 382.1 ± 283.1 ml, p<0.001). At short-term follow-up, the combined group presented a higher JOARR than the posterior group (posterior group: 50.7%±46.6%, combined group: 70.4%±20.3%, p = 0.024), while no significant difference in JOARR was observed between the groups at long-term follow-up (posterior group: 49.2%±48.5%, combined group: 59.6%±47.6%, p = 0.136). No significant difference was found in the overall complication and reoperation rates. CONCLUSIONS: For MDCM patients with ISI, both posterior and one-stage posteroanterior approaches could achieve considerable neurological alleviations in short-term and long-term follow-up. With greater surgical trauma, the combined group presented better short-term JOARR but did not show higher efficacy in long-term neurological function preservation in patients with comparable preoperative conditions.

Corpus Callosum-Mediated Interhemispheric Interactions in Cervical Spondylotic Myelopathy.

PURPOSE: The corpus callosum is crucial for interhemispheric interactions in the motor control of limb functions. Human and animal studies suggested spinal cord pathologies may induce cortical reorganization in sensorimotor areas. We investigate participation of the corpus callosum in executions of a simple motor task in patients with cervical spondylotic myelopathy (CSM) using transcranial magnetic stimulation. METHODS: Twenty patients with CSM with various MRI grades of severity of cord compression were compared with 19 normal controls. Ipsilateral silent period, contralateral silent period, central motor conduction time, and transcallosal conduction time (TCT) were determined. RESULTS: In both upper and lower limbs, TCTs were significantly increased for patients with CSM than normal controls ( p < 0.001 for all), without side-to-side differences. Ipsilateral silent period and contralateral silent period durations were significantly increased bilaterally for upper limbs in comparison to controls ( p < 0.01 for all), without side-to-side differences. There were no significant correlations of TCT with central motor conduction time nor severity of CSM for both upper and lower limbs ( p > 0.05 for all) bilaterally. CONCLUSIONS: Previous transcranial magnetic stimulation studies show increased motor cortex excitability in CSM; hence, increased TCTs observed bilaterally may be a compensatory mechanism for effective unidirectional and uniplanar execution of muscle activation in the distal limb muscles. Lack of correlation of TCTs with severity of CSM or central motor conduction time may be in keeping with a preexistent role of the corpus callosum as a predominantly inhibitory pathway for counteracting redundant movements resulting from increased motor cortex excitability occurring after spinal cord lesions.

Specific electromyography characteristics can distinguish longitudinally extensive transverse myelitis from congestive myelopathy due to spinal dural arteriovenous fistula: a retrospective study.

Aims/Background Although electromyography has been extensively used in the diagnosis of neurological diseases, there is no comprehensive understanding of the electromyography manifestations of spinal dural arteriovenous fistula. Given the widespread use of electromyography in the diagnosis of neurological conditions, it is worthwhile to holistically analyse the electromyography findings of spinal dural arteriovenous fistula to differentiate it from neurological diseases that share similar clinical manifestations. The aim of this study is to evaluate whether electromyography can distinguish spinal dural arteriovenous fistula from longitudinally extensive transverse myelitis. Methods We holistically reviewed files of all patients who were diagnosed with spinal dural arteriovenous fistula or longitudinally extensive transverse myelitis at The First Medical Centre of PLA General Hospital from 1 January 2010 to 31 December 2020. We compared the symptomology, epidemiology, and imaging results of patients with spinal dural arteriovenous fistula and longitudinally extensive transverse myelitis, placing emphasis on their electromyography manifestations. Student's t test was used to analyse normally distributed data, while Chi-square test was used to compare classification statistics. Results Lesions of spinal dural arteriovenous fistula shown on images tend to appear at lower lumbar and sacral segments, whereas lesions of the cervical and upper thoracic segments are more characteristic of longitudinally extensive transverse myelitis. Spinal dural arteriovenous fistula patients and longitudinally extensive transverse myelitis patients overlap in terms of clinical manifestations. After comparison, the two groups of patients had different demographics (age, sex), onset mode, predisposing factors before onset, and electromyographic features. The electromyographic features of patients with spinal dural arteriovenous fistula were associated with neurogenic damage (p < 0.001). Conclusions In patients with spinal dural arteriovenous fistula, electromyography can help clinicians to identify early disease, avoid patient treatment delay, and eliminate unnecessary treatment.

Riluzole for Degenerative Cervical Myelopathy: A Secondary Analysis of the CSM-PROTECT Trial.

Importance: The modified Japanese Orthopaedic Association (mJOA) scale is the most common scale used to represent outcomes of degenerative cervical myelopathy (DCM); however, it lacks consideration for neck pain scores and neglects the multidimensional aspect of recovery after surgery. Objective: To use a global statistical approach that incorporates assessments of multiple outcomes to reassess the efficacy of riluzole in patients undergoing spinal surgery for DCM. Design, Setting, and Participants: This was a secondary analysis of prespecified secondary end points within the Efficacy of Riluzole in Surgical Treatment for Cervical Spondylotic Myelopathy (CSM-PROTECT) trial, a multicenter, double-blind, phase 3 randomized clinical trial conducted from January 2012 to May 2017. Adult surgical patients with DCM with moderate to severe myelopathy (mJOA scale score of 8-14) were randomized to receive either riluzole or placebo. The present study was conducted from July to December 2023. Intervention: Riluzole (50 mg twice daily) or placebo for a total of 6 weeks, including 2 weeks prior to surgery and 4 weeks following surgery. Main Outcomes and Measures: The primary outcome measure was a difference in clinical improvement from baseline to 1-year follow-up, assessed using a global statistical test (GST). The 36-Item Short Form Health Survey Physical Component Score (SF-36 PCS), arm and neck pain numeric rating scale (NRS) scores, American Spinal Injury Association (ASIA) motor score, and Nurick grade were combined into a single summary statistic known as the global treatment effect (GTE). Results: Overall, 290 patients (riluzole group, 141; placebo group, 149; mean [SD] age, 59 [10.1] years; 161 [56%] male) were included. Riluzole showed a significantly higher probability of global improvement compared with placebo at 1-year follow-up (GTE, 0.08; 95% CI, 0.00-0.16; P = .02). A similar favorable global response was seen at 35 days and 6 months (GTE for both, 0.07; 95% CI, -0.01 to 0.15; P = .04), although the results were not statistically significant. Riluzole-treated patients had at least a 54% likelihood of achieving better outcomes at 1 year compared with the placebo group. The ASIA motor score and neck and arm pain NRS combination at 1 year provided the best-fit parsimonious model for detecting a benefit of riluzole (GTE, 0.11; 95% CI, 0.02-0.16; P = .007). Conclusions and Relevance: In this secondary analysis of the CSM-PROTECT trial using a global outcome technique, riluzole was associated with improved clinical outcomes in patients with DCM. The GST offered probability-based results capable of representing diverse outcome scales and should be considered in future studies assessing spine surgery outcomes.

Hoffmann's sign in cervical spondylotic myelopathy patients: pathological insights from neuroimaging.

OBJECTIVE: Hoffmann's sign testing is a commonly used physical examination in clinical practice for patients with cervical spondylotic myelopathy (CSM). However, the pathophysiological mechanisms underlying its occurrence and development have not been thoroughly investigated. Therefore, the present study aimed to explore whether a positive Hoffmann's sign (PHS) in CSM patients is associated with spinal cord and brain remodeling and to identify potential neuroimaging biomarkers with diagnostic value. METHODS: Seventy-six patients with CSM and 40 sex- and age-matched healthy controls (HCs) underwent multimodal MRI. Based on the results of the Hoffmann's sign examination, patients were divided into two groups: those with a PHS (n = 38) and those with a negative Hoffmann's sign (NHS; n = 38). Quantification of spinal cord and brain structural and functional parameters of the participants was performed using various methods, including functional connectivity analysis, voxel-based morphometry, and atlas-based analysis based on functional MRI and structural MRI data. Furthermore, this study conducted a correlation analysis between neuroimaging metrics and neurological function and utilized a support vector machine (SVM) algorithm for the classification of PHS and NHS. RESULTS: In comparison with the NHS and HC groups, PHS patients exhibited significant reductions in the cross-sectional area and fractional anisotropy (FA) of the lateral corticospinal tract (CST), reticulospinal tract (RST), and fasciculus cuneatus, concomitant with bilateral reductions in the volume of the lateral pallidum. The functional connectivity analysis indicated a reduction in functional connectivity between the left lateral pallidum and the right angular gyrus in the PHS group. The correlation analysis indicated a significant positive association between the CST and RST FA and the volume of the left lateral pallidum in PHS patients. Furthermore, all three variables exhibited a positive correlation with the patients' motor function. Finally, using multimodal neuroimaging metrics in conjunction with the SVM algorithm, PHS and NHS were classified with an accuracy rate of 85.53%. CONCLUSIONS: This research revealed a correlation between structural damage to the pallidum and RST and the presence of Hoffmann's sign as well as the motor function in patients with CSM. Features based on neuroimaging indicators have the potential to serve as biomarkers for assessing the extent of neuronal damage in CSM patients.

Hepatic myelopathy neurological complication of chronic liver disease: two case reports.

BACKGROUND: Hepatic myelopathy is a very rare neurological complication of chronic liver disease. Patients habitually present with progressive pure motor spastic paraparesis. This neurological dysfunction is almost always due to cirrhosis and portocaval shunt, either surgical or spontaneous. CASES REPORT: We report two cases of a 57-year-old man and a 37-year-old woman with progressive spastic paraparesis linked to cirrhosis and portal hypertension. The two patients are of Tunisian origin (north Africa). Magnetic resonance imaging of the spinal cord of two patients was normal, while brain magnetic resonance imaging showed a T2 hypersignals of the pallidums. These signs, in favor of hepatic encephalopathy in the two patients with cirrhosis with isolated progressive spastic paraparesis without bladder or sensory disorders, help to retain the diagnosis of hepatic myelopathy. CONCLUSION: Hepatic myelopathy is a severe and debilitating neurological complication of chronic liver disease. The pathogenesis is misunderstood and seems to be multifactorial, including the selective neurotoxic role both of ammonia and other pathogenic neurotoxins. Usually a pathological brain magnetic resonance imaging showing a hepatic encephalopathy was documented, contrasting with a normal spinal cord magnetic resonance imaging that contributed to diagnosis of hepatic myelopathy. Conservative therapies such as ammonia-lowering measures, diet supplementation, antispastic drugs, and endovascular shunt occlusion show little benefit in improving disease symptoms. Liver transplantation performed at early stage can prevent disease progression and could probably allow for recovery.

[Importance of neuro-urological care in patients with spinal cord injuries/diseases]. / Stellenwert der neuro-urologischen Betreuung von Patienten mit Rückenmarkverletzungen/-erkrankungen.

Integrity, control and regulation of the urinary tract are subject to a complex neuronal regulation, in which portions of the sympathetic, parasympathetic and somatic nervous system are involved. The spinal cord plays a central role in regulation and serves as a transmitter for the motor and sensory pathways. Bladder dysfunction followed by renal dysfunction was the most frequent cause of death in patients with spinal cord injuries/diseases (paraplegia) as recently as half a decade ago. Thanks mainly to diagnostic and therapeutic advances made in neuro-urology, urological problems are no longer life-limiting. A vital role is played not only by the actual function of the urinary tract but also by the complex interactions in patients living with paraplegia. Issues such undertreated hyperactivity of the detrusor muscle with autonomous dysregulation, incontinence with secondary skin changes, or insufficient hand function to perform intermittent catheterisation must be evaluated in an interdisciplinary approach. Spinal cord injury/disease implies numerous functional disorders and secondary impairments of the organism. In addition to bladder function, sexual dysfunction also plays a crucial role. Especially in younger patients who sustain paraplegia before or during the family planning phase, this disruption and limitation is an essential reason for reduced quality of life. Neurogenic intestinal function plays an additional crucial role with regard to quality of life and management of everyday life. In recent years, the range of neuro-urological topics has expanded significantly. The focus of our work shifted from being merely on the urinary tract and urodynamics. In particular, the diagnostic investigation and treatment of neurogenic intestinal dysfunction is increasingly in the hands of neuro-urologists. The complex presentation of paraplegia involves an interaction of bladder, intestinal and sexual dysfunction in a way that these influence one another. Therefore, the sustained care and re-integration of these patients essentially includes lifelong and regular neuro-urological care in a paraplegia centre. Last but not least, it is exactly these neuro-urological topics such as urinary tract infections, urinary and intestinal incontinence and faecal impaction, which most commonly lead to re-hospitalisation.

Three-Dimensional Computed Tomography Image Reformation for Comparison of Foraminal Cross-Sectional Dimension in Patients Who Have Undergone Laminoplasty and Laminectomy with Fusion.

PURPOSE OF THE STUDY: Laminectomy with fusion (LF) is commonly performed with laminoplasty (LP) for cervical myelopathy. Foraminal stenosis is important in the surgical treatment of cervical myelopathy. LF and LP can affect foraminal size in different ways. This study aimed to compare foraminal dimensions after LF and LP using a medical computer-assisted design (CAD) program. MATERIAL AND METHODS: Computed tomography (CT) scans of the cervical vertebrae of 16 patients with cervical myelopathy were retrospectively viewed in the Digital Imaging and Communications in Medicine format on a CAD program. CT images were reformatted in an oblique plane perpendicular to the long axis of each foramen from C2-C3 to C6-C7. The narrowest foraminal crosssectional dimension (FCD) was measured and compared between the LF and LP groups at the operated, non-operated, and C4-C5 levels. The difference between the preoperative and postoperative FCDs was also calculated and compared between the operated and C4-C5 levels. Intra- and interobserver reliabilities for FCD measurements were evaluated using intraclass correlation coefficients. RESULTS AND DISCUSSION: At the operated spinal levels, the LF and LP groups showed decreased and increased mean FCDs, respectively. At the adjacent non-operated levels, the mean FCD slightly increased in both the groups. In the LF group, the difference between the preoperative and postoperative FCDs in the C4-C5 levels was larger than that in the other operated levels, but this difference was insignificant. CONCLUSIONS: LF and LP showed contrary results for FCD. Therefore, FCD and kyphosis should be considered for LF and LP. KEY WORDS: three-dimensional, foraminal cross-sectional dimension, laminoplasty, laminectomy fusion, computer-aided design, drafting system, preoperative-postoperative comparison.

Surgical treatment for recurrent thoracic ventral intradural arachnoid cyst secondary to tuberculous meningitis: a case report.

INTRODUCTION: Spinal intradural arachnoid cysts (SIACs) are rare spinal entities that are categorized as primary or secondary pathologies. Secondary cysts can arise from various traumatic or inflammatory causes including subarachnoid hemorrhage, intrathecal injection or surgery, and infectious meningitis/arachnoiditis. Only a few cases of SIAC secondary to tuberculous meningitis have been previously reported, without details of the surgical treatment. CASE PRESENTATION: A 27-year-old woman diagnosed with tuberculous meningitis developed myelopathy caused by thoracic ventral SIAC and intradural abscess. The patient underwent abscess evacuation and cyst fenestration; however, cyst recurrence occurred. The 2nd surgery consisted of cyst resection via a posterolateral approach with expansive duraplasty and spinal arthrodesis. Re-recurrence occurred, and at the 3rd surgery, cyst-subarachnoid bypass was performed. One year after the 3rd surgery, the myelopathic symptoms recovered, and MR images demonstrated a decreased cyst size. DISCUSSION: Here, we report a rare case of recurrent thoracic SIAC secondary to tuberculous meningitis and arachnoiditis. Simple fenestration is associated with a high risk of recurrence in this pathology. Ventrally located thoracic cysts can be approached with posterolateral approach with pedicles resected followed by instrumented arthrodesis. Even in cases involving gross total resection of the cyst wall, there is a risk of recurrence. In such cases, cyst-subarachnoid bypass with a large-diameter tube can be effective.

Nitrous Oxide-induced Myeloneuropathy Due to Recreational Abuse.

BACKGROUND: The recreational use of nitrous oxide (N2O) has increased in recent years with a noticeable surge in the incidence of nitrous oxide-related myeloneuropathy. OBJECTIVES: To raise awareness of increasing myeloneuropathy due to recreational nitrous oxide misuse in Israel. METHODS: We conducted a case series documenting the clinical and investigative features of eight patients presenting with nitrous oxide-induced myeloneuropathy who were admitted to our departments. RESULTS: Paresthesia was the chief complaint in all patients, with sensory gait ataxia being a common feature, which was often accompanied by Romberg's sign and mild lower limb weakness. Vitamin B12 levels were below the normal range in seven patients, accompanied by elevated homocysteine and methylmalonic acid levels. Magnetic resonance imaging scans revealed hyperintense signals in the dorsal columns of the cervical spine. All patients improved following vitamin B12 injections. CONCLUSIONS: Enhancing awareness, prompting the use of appropriate investigations, and advocating for timely treatment are needed to overcome the risks associated with nitrous oxide misuse.