Clinical Features and Surgical Management of Intramedullary Schwannoma of the Spinal Cord.

BACKGROUND: Intramedullary schwannoma is a relatively rare tumor with only a few literature reports. This study was aimed to report the clinical characteristics of intramedullary schwannoma and discuss imaging findings and treatment strategies. METHODS: The inclusion criterion was consecutive patients with intramedullary schwannomas who were surgically treated in our institution between 2017 and 2022. Data included clinical characteristics, radiologic features, surgical management, and prognosis. Clinical and follow-up details of all cases were collected and reviewed. RESULTS: This study included 3 male and 8 female patients. The mean age was 45 years (range 26-77 years). Cervical spine (4 cases, 36.4%), thoracic spine (4 cases, 36.4%), and lumbosacral spine (3 cases, 27.3%) involvement was found. Weakness, numbness and pain of limbs were the main symptoms at administration. Preoperative magnetic resonance imaging demonstrated lesion with spinal cord medullary invasion and well demarcated margins. The postoperative histologic examination showed benign lesions and confirmed the schwannoma. CONCLUSIONS: This article presented a series of 11 cases of intramedullary schwannoma with sharp margins and well-enhanced features. Prognosis and functional recovery were good after gross total resection.

Mesenchymal Stem Cell-Derived Mitochondria Enhance Extracellular Matrix-Derived Grafts for the Repair of Nerve Defect.

Peripheral nerve injuries (PNI) can lead to mitochondrial dysfunction and energy depletion within the affected microenvironment. The objective is to investigate the potential of transplanting mitochondria to reshape the neural regeneration microenvironment. High-purity functional mitochondria with an intact structure are extracted from human umbilical cord-derived mesenchymal stem cells (hUCMSCs) using the Dounce homogenization combined with ultracentrifugation. Results show that when hUCMSC-derived mitochondria (hUCMSC-Mitos) are cocultured with Schwann cells (SCs), they promote the proliferation, migration, and respiratory capacity of SCs. Acellular nerve allografts (ANAs) have shown promise in nerve regeneration, however, their therapeutic effect is not satisfactory enough. The incorporation of hUCMSC-Mitos within ANAs has the potential to remodel the regenerative microenvironment. This approach demonstrates satisfactory outcomes in terms of tissue regeneration and functional recovery. Particularly, the use of metabolomics and bioenergetic profiling is used for the first time to analyze the energy metabolism microenvironment after PNI. This remodeling occurs through the enhancement of the tricarboxylic acid cycle and the regulation of associated metabolites, resulting in increased energy synthesis. Overall, the hUCMSC-Mito-loaded ANAs exhibit high functionality to promote nerve regeneration, providing a novel regenerative strategy based on improving energy metabolism for neural repair.

Total body bone mineral density and various spinal disorders: a Mendelian randomization study.

Introduction: Observational studies have yielded inconsistent findings regarding the correlation between bone mineral density (BMD) and various spinal disorders. To explore the relationship between total-body BMD and various spinal disorders further, we conducted a Mendelian randomization analysis to assess this association. Methods: Two-sample bidirectional Mendelian randomization (MR) analysis was employed to investigate the association between total-body BMD and various spinal disorders. The inverse-variance weighted (IVW) method was used as the primary effect estimate, and additional methods, including weighted median, MR-Egger, simple mode, and weighted mode, were used to assess the reliability of the results. To examine the robustness of the data further, we conducted a sensitivity analysis using alternative bone-density databases, validating the outcome data. Results: MR revealed a significant positive association between total-body BMD and the prevalence of spondylosis and spinal stenosis. When total-body BMD was considered as the exposure factor, the analysis demonstrated an increased risk of spinal stenosis (IVW odds ratio [OR] 1.23; 95% confidence interval [CI], 1.14-1.32; P < 0.001) and spondylosis (IVW: OR 1.24; 95%CI, 1.16-1.33; P < 0.001). Similarly, when focusing solely on heel BMD as the exposure factor, we found a positive correlation with the development of both spinal stenosis (IVW OR 1.13, 95%CI, 1.05-1.21; P < 0.001) and spondylosis (IVW OR 1.10, 95%CI, 1.03-1.18; P = 0.0048). However, no significant associations were found between total-body BMD and other spinal disorders, including spinal instability, spondylolisthesis/spondylolysis, and scoliosis (P > 0.05). Conclusion: This study verified an association of total-body BMD with spinal stenosis and with spondylosis. Our results imply that when an increasing trend in BMD is detected during patient examinations and if the patient complains of numbness and pain, the potential occurrence of conditions such as spondylosis or spinal stenosis should be investigated and treated appropriately.

Neuroblastoma of the lumbosacral canal in an adult: a case report and literature review.

Neuroblastoma (NB) is a leading cause of death in children. It usually occurs in the adrenal gland and rarely in the spinal canal. Here, we report the case of a 48-year-old male patient with abnormal thickening of the cauda equina nerve as revealed by lumbosacral magnetic resonance imaging. The patient's main clinical manifestations were numbness and pain in both lower limbs. The patient underwent surgical treatment; however, intraoperatively, an unclear border was observed between the cauda equina nerve and the tumor; therefore, the tumor was not forcibly excised. The postoperative pathological results were reported as NB. The disease known as NB, which is extremely rare. We believe that a pathological biopsy is extremely vital for diagnosing NB, and aggressive post-operative radio-chemotherapy could potentially prolong the patient's survival time.

Thoracic Anterior Spinal Cord Herniation: Treatment and Prognosis Outcome of Seven Patients.

BACKGROUND: This study aimed to investigate the diagnosis and treatment of thoracic anterior spinal cord herniation, a rare condition. METHODS: Clinical data of 7 patients diagnosed with thoracic anterior spinal cord herniation were analyzed. All patients were diagnosed with a complete preoperative examination and scheduled for surgical treatment. In addition, regular follow-up was performed after the surgery, and the operation's efficacy was evaluated according to clinical symptoms, imaging findings, and improvement in neurologic function. RESULTS: All patients underwent spinal cord release with an anterior dural patch. Notably, no severe postoperative surgical complications were observed. All patients were followed up for 12-75 months, with an average duration of approximately 46.5 months. Post-operative pain symptoms were controlled, neurological dysfunction and related symptoms improved to varying degrees, and anterior spinal cord herniation did not recur. The modified Japanese Orthopedic Association score at the last follow-up was significantly higher than the preoperative score. CONCLUSIONS: Clinicians should avoid misdiagnosing patients with thoracic anterior spinal cord herniation with intervertebral disc herniation, arachnoid cysts, and other related diseases, and patients should undergo surgical treatment as early as possible. In addition, surgical treatment can protect the neurologic function of patients and effectively prevent the aggravation of clinical symptoms.

Sacral neuromodulation remote programming in patients with refractory lower urinary tract dysfunction: China's experience during the COVID-19 pandemic.

Objectives: Sacral neuromodulation is an effective, minimally invasive treatment for refractory lower urinary tract dysfunction. However, regular postoperative programming is crucial for the maintenance of the curative effects of electronic sacral stimulator devices. The outbreak of coronavirus disease 2019 (COVID-19) limited the ability of practitioners to perform traditional face-to-face programming of these stimulators. Therefore, this study aimed to evaluate the application of remote programming technology for sacral neuromodulation during the COVID-19 pandemic in China. Materials and methods: We retrospectively collected data including baseline and programming information of all patients with lower urinary tract dysfunction who underwent sacral neuromodulation remote programming in China after the outbreak of COVID-19 (i.e., December 2019). The patients also completed a self-designed telephone questionnaire on the subject. Results: A total of 51 patients from 16 centers were included. They underwent 180 total remote programming visits, and 118, 2, 25, and 54 voltage, current, pulse width, and frequency adjustments, respectively, were performed. Additionally, remote switching on and off was performed 8 times; impedance test, 54 times; and stimulation contact replacement, 25 times. The demand for remote programming was the highest during the first 6 months of sacral neuromodulation (average, 2.39 times per person). In total, 36 out of the 51 patients completed the questionnaire survey. Of these, all indicated that they chose remote programming to minimize unnecessary travel because they had been affected by COVID-19. The questionnaire also showed that remote programming could reduce the number of patient visits to the hospital, save time, reduce financial costs, and would be easy for patients to master. All surveyed patients indicated that they were satisfied with remote programming and were willing to recommend it to other patients. Conclusion: Remote programming for sacral neuromodulation is feasible, effective, safe, and highly recommended by patients with refractory lower urinary tract dysfunction. Remote programming technology has great development and application potential in the post-pandemic era.

Spinal nerve root sleeve cysticercosis: a case report and review of the literature.

BACKGROUND: Neurocysticercosis is a parasitic infection of the central nervous system by tapeworm larvae. Spinal cysticercosis is thought to be relatively rare, and spinal nerve root sleeve cysticercosis have not been reported previously. CASE PRESENTATION: A 46-year-old Chinese Han female patient presented with low back pain and radicular pain of the right lower limb. The visual analog scale was 6. Magnetic resonance imaging showed a subarachnoid cyst at the S1 level, with a slight enhanced rim. The patient underwent surgical treatment. During surgery, we found the cyst located mainly in the subarachnoid space and partly in a sacral nerve root sleeve. Cysticercosis was also confirmed by postoperative pathological examination. Postoperative drug therapy was performed after cysticercosis was confirmed. Postoperatively, the patient was treated with oral albendazole (15 mg/kg) for 1 month. Only mild sensory impairment was left when she was discharged. After 3 years of follow-up, the visual analog scale reduced from 6 to 2, and the patient's sensory function completely recovered. Magnetic resonance imaging showed no recurrence of cysticercosis. CONCLUSION: Subarachnoid cysticercosis may extend to nerve root sleeve causing back pain and radiculopathy, which may present with similar magnetic resonance imaging manifestations to Tarlov cysts. Hence, spinal subarachnoid cysticercosis should be considered as an important differential diagnosis of arachnoid cyst and sacral Tarlov cyst. Combined treatment with surgical removal and drug therapy is effective to manage spinal subarachnoid cysticercosis.

An Effective Surgical Method for Terminal Syringomyelia: Terminal Ventriculostomy-Associated "V"-Type Ostomy.

STUDY DESIGN: Retrospective cohort study. OBJECTIVES: We aimed to evaluate the effectiveness of terminal ventriculostomy in treating tethered cord syndrome (TCS) combined with terminal syringomyelia (TS) and describe "V"-type ostomy as an effective surgical method to avoid relapsing syringomyelia based on terminal ventriculostomy. METHODS: We retrospectively analyzed the clinical and radiological data of 28 patients admitted to the Department of Neurosurgery, PLA General Hospital who had been diagnosed with TCS combined with TS and underwent terminal ventriculostomy-associated "V"-type ostomy between January 2011 and January 2016. We classified patients' clinical outcomes into 4 levels according to the Spinal Bifida Neurological Scale: markedly improved, improved, stable, and deteriorated. The size of the syrinx cavity was quantified using the syrinx index, and there was a difference in syrinx cavity size between pre-operation and post-operation. RESULTS: Twenty-eight patients were followed up for 36 months. We found that each syrinx cavity shrunk by at least 50%. More than 90% of patients had achieved "markedly improved" and "improved" outcomes during the follow-up visit. Moreover, no patient relapsed for up to 36 months post-surgery. CONCLUSION: Terminal ventriculostomy has a beneficial effect on TS, particularly on the syrinx cavity extending to the filum terminale. For this special cavity, we advocate the use of terminal ventriculostomy-associated "V"-type ostomy to avoid potential relapse. As a safe, convenient, and persistently effective approach, terminal ventriculostomy-associated "V"-type ostomy can be considered a promising alternative method for treating TCS combined with TS in clinical practice.

Gestational age-specific reference standards of low-lying conus medullaris level in fetuses: a prospective cohort study.

PURPOSE: To explore the position change of fetal conus medullaris by ultrasound, and to propose gestational age-specific references for the lower limits of fetal conus medullaris level. METHODS: We prospectively collected the imaging and clinical data of fetuses whose mothers accepted routine prenatal ultrasonic follow-ups in the Department of Medical Ultrasonics, Chinese PLA General Hospital, between November 2020 and April 2021. By assigning to the conus medullaris levels, calculating statistical data, and performing linear regression analysis, we determined the correlation between the conus medullaris level and gestational week, as well as between the 95th percentile of the conus medullaris level, i.e., the lower limit of the conus medullaris level, and gestational week. RESULTS: We included 1202 different fetuses at 17-40 gestational weeks in the study. Both the conus medullaris level and the 95th percentile of the conus medullaris level were linearly correlated with gestational week. We calculated the adjusted values of the lower limits of fetal conus medullaris levels, that is, the theoretical references of the lower limits, according to the linear regression equation, and composed a comparison table. CONCLUSION: The fetal conus medullaris position continues changing cranially with gestational weeks during the whole pregnancy. The conus medullaris of a term fetus should not lie below the L2 vertebra level at birth. We proposed reference criteria of fetal low-lying conus medullaris for each gestational week from 17 to 40 weeks of gestational age, which potentially help prompt diagnosis and improve prognosis of fetal tethered cord syndrome.

Fetal magnetic resonance imaging in the diagnosis of spinal cord neural tube defects: A prospective study.

Objective: This study aimed to evaluate the value of fetal magnetic resonance imaging (MRI) in the prenatal diagnosis of spinal neural tube defects. Methods: From August 2018 to January 2021, 56 fetuses with suspected spinal cord neural tube defects were treated by prenatal ultrasound in the Neurosurgery Department of the First Medical Center of the People's Liberation Army General Hospital. Fetal MRI was performed within 72 h after ultrasound diagnosis. Forty singleton fetuses were selected. Magnetic resonance examination was performed within 1 month after birth, and the diagnostic coincidence rates of prenatal ultrasound and fetal magnetic resonance examination in the prenatal diagnosis of spinal cord neural tube defects were compared and analyzed using postnatal magnetic resonance examination as the standard. Results: The coincidence rates of prenatal ultrasound and fetal MRI for the prenatal diagnosis of spina bifida were 71.4% (20/28) and 39.2% (11/28), respectively, and the difference was statistically significant. The coincidence rates of prenatal ultrasound and fetal MRI in the diagnosis of intraspinal lipoma were 52.6% (10/19) and 73.7% (14/19), respectively, and the difference was statistically significant. Conclusion: Fetal MRI has an advantage over prenatal ultrasound in detecting intraspinal lipoma. Prenatal ultrasound has an advantage over fetal MRI in detecting spina bifida.

Functional, morphological and molecular characteristics in a novel rat model of spinal sacral nerve injury-surgical approach, pathological process and clinical relevance.

Spinal sacral nerve injury represents one of the most serious conditions associated with many diseases such as sacral fracture, tethered cord syndrome and sacral canal tumor. Spinal sacral nerve injury could cause bladder denervation and detrusor underactivity. There is limited clinical experience resolving spinal sacral nerve injury associated detrusor underactivity patients, and thus the treatment options are also scarce. In this study, we established a spinal sacral nerve injury animal model for deeper understanding and further researching of this disease. Forty 8 w (week) old Sprague Dawley rats were included and equally divided into sham (n = 20) and crush group (n = 20). Bilateral spinal sacral nerves of rats were crushed in crush group, and sham group received same procedure without nerve crush. Comprehensive evaluations at three time points (1 w, 4 w and 6 w) were performed to comprehend the nature process of this disease. According to urodynamic test, ultrasonography and retrograde urography, we could demonstrate severe bladder dysfunction after spinal sacral nerve injury along the observation period compared with sham group. These functional changes were further reflected by histological examination (hematoxylin-eosin and Masson's trichrome staining) of microstructure of nerves and bladders. Immunostaining of nerve/bladder revealed schwann cell death, axon degeneration and collagen remodeling of bladder. Polymerase Chain Reaction results revealed vigorous nerve inflammation and bladder fibrosis 1 week after injury and inflammation/fibrosis returned to normal at 4 w. The CatWalk gait analysis was performed and there was no obvious difference between two groups. In conclusion, we established a reliable and reproducible model for spinal sacral nerve injury, this model provided an approach to evaluate the treatment strategies and to understand the pathological process of spinal sacral nerve injuries. It allowed us to understand how nerve degeneration and bladder fibrosis changed following spinal sacral nerve injury and how recovery could be facilitated by therapeutic options for further research.

Filum Terminale: A Comprehensive Review with Anatomical, Pathological, and Surgical Considerations.

The conus medullaris is the distal tapering end of the spinal cord, and the filum terminale (FT) is regarded as a bundle of nonfunctional fibrous tissue; therefore, some scholars call it the spinal ligament, while others describe the human FT as "remnants of the spinal cord." It was later found that in the human spinal cord, the FT is composed of an intradural segment and an epidural segment, and the end of the FT is connected to the coccyx periosteum. Because some nerve tissue is also found in the FT, as research progresses, FT may have the potential for transplantation. A lack of exhaustive overviews on the FT in the present literature prompted us to conduct this review. Considering that a current comprehensive review seemed to be the need of the hour, herein, we attempted to summarize previous research and theories on the FT, elucidate its anatomy, and understand its pathological involvement in various diseases.

Ruptured Spinal Dermoid Cysts with Lipid Droplets into the Syrinx Cavity : Reports of Fourteen Cases.

OBJECTIVE: Dermoid cysts are uncommon in spinal cord tumors, and the phenomenon of their spontaneous rupture into the syrinx cavity is quite rare. We aimed to analyze the imaging characteristics and etiologies, and propose some surgical strategies, for this uncommon phenomenon. METHODS: We retrospectively reviewed 14 cases with spinal dermoid cysts that ruptured into the cervical and thoracic syrinx cavity. There were six male and eight female cases, aged 21 to 46 years, who had lipid droplets in the syrinx cavity from C1 to L3. The dermoid cysts were always located at the conus. Based on patients' complaints, clinical manifestations, and imaging results, we adopted tumor excision and/or syrinx cavity aspiration in one stage or multiple stages. RESULTS: Three patients had only a syrinx cavity aspiration surgery due to a history of dermoid cyst excision. Eight patients had dermoid cyst resection and syrinx cavity aspiration in one stage. One patient was operated upon in two stages due to the development of new symptoms at nine months follow-up. Two patients underwent only tumor resection since they did not show similar symptoms or signs caused by the cervicothoracic syrinx. The axial magnetic resonance imaging indicated that the lipid droplets were always not at the center but were eccentric. The clinical effect was satisfactory during the follow-up period in this group. CONCLUSION: The lipid droplets filled the spinal syrinx cavity, not entirely confined to the central canal. Based on the chief complaints and associated signs, we adopted different surgical strategies and had satisfactory clinical results.

Early Surgical Intervention with Antibiotic Treatment for Congenital Dermal Sinus with Central Nervous System Infection: A Retrospective Study of 20 Cases.

OBJECTIVE: To investigate the efficacy of surgical intervention with antibiotic treatment for congenital dermal sinus (CDS) with central nervous system infection. METHODS: Clinical data of 20 patients with CDS and central nervous system infection were retrospectively analyzed. All patients received early surgical treatment combined with postoperative antibiotic therapy after the diagnosis was confirmed. The infection control effect was evaluated according to the clinical symptoms, laboratory examination results, and improvement of neurological function. RESULTS: All 20 patients were treated with complete resection of the CDS and postoperative antibiotic therapy. No severe surgical complications occurred. Patients were followed for 3-81 months with a median follow-up time of 37.5 months. Postoperative infection was effectively controlled with no recurrence. Neurological dysfunction and related symptoms improved to varying extents after treatment, and the Spina Bifida Neurological Scale score at the final follow-up significantly increased. CONCLUSIONS: Patients with CDS and central nervous system infection should receive surgical management at an early stage with antibiotic treatment. This treatment algorithm was effective for control infection and protection of neurological function.

Type 1.5 Split Cord Malformation : A New Theory of Pathogenesis.

To report two cases of type 1.5 split cord malformation (SCM), a subtype of SCM with combined characteristics of types I and II and to review the relevant literature and propose a new possible pathogenetic theory for type 1.5 SCM. A 52-year-old woman had hemicords within a single dural sac with a dorsal bony septum at the L5 level. A 9-year-old boy had hemicords within a single dural sac with a ventral bony septum and fibrous extension at the L3 level. Both patients underwent microsurgical treatments for removing the bony septum, detethering the spinal cord, and sectioning the filum terminale. The surgical procedure revealed an extradural partial bony septum and hemicords within an intact single dural sac in each patient. Both patients were discharged from the hospital without de novo nerve dysfunction. Published cases have validated that types I and II SCM can overlap. We recommend recent type 1.5 SCM as a normative terminology for this overlapping SCM and report two rare cases of this SCM. We propose an associated pathogenesis consisting of uneven distribution and regression to explain type 1.5 SCM. Furthermore, we postulate that the amount of condensing meninx primitiva might determine whether the left bony septum has fibrous extensions to the opposite dura in type 1.5 SCM.

Determination of the normal conus medullaris level in term infants: the role of MRI in early infancy.

OBJECTIVE: This study aimed to explore the migration process of the conus medullaris (CM) in early infancy using infant MRI and to evaluate the application of MRI for locating the infant CM level. METHODS: The authors retrospectively analyzed the CM level on the lumbosacral MR images of 26 term infants aged < 3 months who were classified into three groups according to age. The authors numbered the CM level in each patient and analyzed the range and average of the CM level of the cohort. The authors studied the linear correlation between CM level and postnatal days with linear regression analysis, 1-way ANOVA, and the least significant difference test. RESULTS: The CM level ranged from the superior border of the L1 vertebra to the top third of the L3 vertebra. About 96.2% of infants had CM higher than the superior border of the L3 vertebra. On average, CM was located between the L1-2 intervertebral disc and the inferior border of the L2 vertebra (mean ± SD score 1.64 ± 1.14). The three groups had no significant statistical difference in CM level (F = 1.071 and p = 0.359; groups 1 and 2, p = 0.408; groups 1 and 3, p = 0.170; groups 2 and 3, p = 0.755). CM level had no linear regression correlation with postnatal days within the first month (r2 = 0.061, F = 0.654, p = 0.438) or within the first 3 months (r2 = 0.002, F = 0.056, p = 0.816). CONCLUSIONS: The CM level reaches the normal adult level by birth in term infants and does not ascend during childhood. On average, the CM was between the L1-2 intervertebral disc and the inferior border of the L2 vertebra in term infants. Considering the possibility of physiologically low-lying CM, the authors agree that normal CM is located above the L3 level in term infants and CM at the L3 level could be equivocal and should be investigated with other clinical data. The study data suggest that MRI is an accurate and valuable method for determining the CM level in term infants.

Conus medullaris migration during the third trimester: A retrospective study.

OBJECTIVE: To explore the migration process of the conus medullaris (CM) and propose a normal range of CM levels during the third trimester. METHOD: We retrospectively collected the ultrasonographic and clinical data of 588 fetuses during the third trimester. We located the CM and assigned scores. One-way analysis of variance and linear regression analyses were used to statistically analyze CM migration. Statistical significance was set at p < 0.05. RESULTS: The CM levels were statistically different among the different gestational weeks of the third trimester. The CM level showed a linear regression correlation with the gestational weeks. On an average, the CM migrated from the top third of the L2 vertebra to the L1/2 intervertebral disc level. CONCLUSION: The CM continues to migrate, from the top third of the L2 vertebra to the L1/2 intervertebral disc level, during the third trimester. The term infant could have the CM at the normal adult level at birth. At the beginning of the third trimester, a CM located above the L2/3 intervertebral disc level could be normal; the CM location at the L3 vertebra level could be physiological and needs follow-up; and a CM presenting below the L3 vertebra level might indicate tethered cord syndrome. The fetus with a CM significantly above the L1/2 intervertebral disc level may have caudal regression syndrome.