Concurrent Oncolysis and Neurolesion Repair by Dual Gene-Engineered hNSCs in an Experimental Model of Intraspinal Cord Glioblastoma.

Intramedullary spinal cord glioblastoma (ISCG) is lethal due to lack of effective treatment. We previously established a rat C6-ISCG model and the antitumor effect of F3.CD-TK, an hNSC line expressing CD and TK, via producing cytocidal 5FU and GCV-TP. However, the neurotherapeutic potential of this hNSC approach has remained uninvestigated. Here for the first time, cultured F3.CD-TK cells were found to have a markedly higher oncolytic effect, which was GJIC-dependent, and BDNF expression but less VEGF secretion than F3.CD. In Rowett athymic rats, F3.CD-TK (1.5 × 106 cells/10 µL × 2), injected near C6-ISCG (G55 seeding 7 days earlier: 10 K/each) and followed by q.d. (×5/each repeat; i.p.) of 5FC (500 mg/kg/5 mL/day) and GCV (25 mg/kg/1 mL/day), robustly mitigated cardiorespiratory, locomotor, and sensory deficits to improve neurofunction and overall survival compared to animals receiving either F3.CD or F3.CD-TK+F3.CD debris formula. The F3.CD-TK regimen exerted greater tumor penetration and neural inflammation/immune modulation, reshaped C6-ISCG topology to increase the tumor's surface area/volume ratio to spare/repair host axons (e.g., vGlut1+ neurites), and had higher post-prodrug donor self-clearance. The multimodal data and mechanistic leads from this proof-of-principle study suggest that the overall stronger anti-ISCG benefit of our hNSC-based GDEPT is derived from its concurrent oncolytic and neurotherapeutic effects.

The disparity in pediatric spinal cord tumor clinical trials: A scoping review of registered clinical trials from 1989 to 2023.

Background: Spinal cord tumors (SCTs) comprise 10% of all central nervous system (CNS) tumors. Pediatric SCTs are often excluded and underrepresented in clinical trials though exclusion rates haven't been reported. Methods: We reviewed all interventional clinical trials recruiting patients <21 years with SCTs on ClinicalTrials.gov between 1989 and 2023. Results: Five hundred and two CNS tumor trials were identified, of which 255 included SCTs and/or spincal metastases. Among these, 96.5% were open to all CNS tumors (brain or spine); however, only 3.5% were exclusive to spine tumors. One trial was specific to pediatric spine tumors (inclusive of bone, soft tissue, and neural tumors); no trial was specific to primary pediatric SCTs. Most trials were located in North America, with multisite investigations being more common than single-institution designs. Trials frequently evaluated interventions/treatments (89%), supportive care/quality of life measures (7.1%), or diagnostic protocols (3.1%). Among included treatment paradigms, systemic therapies using cytotoxic chemotherapies, targeted therapies, and/or immunotherapies were more common among brain/spine trials, while radiotherapy, surgical adjuncts, and/or local drug delivery more frequently occurred in spinal tumor trials. Conclusions: Though SCTs comprise 10% of pediatric CNS tumors, they remain underrepresented in clinical trials. This lack of trials specific to advancing pediatric SCTs management highlights an area of clinical and research need.

Microsurgical treatment of spinal intradural capillary hemangioma: A consecutive case series of 18 patients and literature review.

PURPOSE: Intradural capillary hemangioma is a rare condition with unclear etiology. Although intradural capillary hemangiomas are benign, they exhibit significant proliferative activity, and their clinical significance should not be underestimated. METHODS: We report a series of spinal intradural capillary hemangiomas to illustrate the characteristics, surgical management, and outcomes. METHODS: A total of 18 consecutive patients who underwent microsurgical treatment were retrospectively reviewed. Patient characteristics were recorded in each case, including presenting symptoms, imaging findings, neurologic status, a surgical procedure performed and follow-up. RESULTS: There were 11(61.1 %) male and 7(38.9 %) female patients, with the ages ranging from 25 to 62 years. The thoracic spine was the most commonly affected site, accounting for 77.8 % (14/18) of the cases. 9 tumors were identified as intradural extramedullary, 3 tumors as intramedullary, and 2 tumors as both extramedullary and intramedullary. There were also 4 cases of tumors localized to the cauda equina. Clinical presentations included back pain, sensory deficits, weakness and gait ataxia with a duration of symptoms ranging from 1 to 12 months. The lesion was hypointense or isointense with the spinal cord on T1- weighted images and hyperintense on T2-weighted images and showed intense enhancement after contrast medium injection. All patients underwent surgical treatment, and no significant postoperative complications were observed. Postoperatively, patients were followed up for an average of 44 months. Follow-up showed that the majority of patients experienced significant improvement in neurological function, with no cases of recurrence. CONCLUSION: Surgical resection is typically the preferred method for treating spinal intradural capillary hemangiomas. Complete resection can relieve spinal cord compression and minimize the risk of recurrence.

The Role of Radiotherapy, Chemotherapy, and Targeted Therapies in Adult Intramedullary Spinal Cord Tumors.

Intramedullary primary spinal cord tumors are rare in adults and their classification has recently evolved. Their treatment most frequently relies on maximal safe surgical resection. Herein, we review, in light of the WHO 2021 classification of central nervous system tumors, the knowledge regarding the role of radiotherapy and systemic treatments in spinal ependymomas, spinal astrocytomas (pilocytic astrocytoma, diffuse astrocytoma, spinal glioblastoma IDH wildtype, diffuse midline glioma H3-K27M altered, and high-grade astrocytoma with piloid features), neuro-glial tumors (ganglioglioma and diffuse leptomeningeal glioneuronal tumor), and hemangioblastomas. In spinal ependymomas, radiotherapy is recommended for incompletely resected grade 2 tumors, grade 3 tumors, and recurrent tumors not amenable to re-surgery. Chemotherapy is used in recurrent cases. In spinal astrocytomas, radiotherapy is recommended for incompletely resected grade 2 astrocytomas and grade 3 or 4 tumors as well as recurrent tumors. Chemotherapy is indicated for newly diagnosed high-grade astrocytomas and recurrent cases. In hemangioblastomas not amenable to surgery, radiotherapy is an effective alternative option. Targeted therapies are playing an increasingly important role in the management of some intramedullary primary spinal cord tumor subtypes. BRAF and/or MEK inhibitors have demonstrated efficacy in pilocytic astrocytomas and glioneuronal tumors, belzutifan in von Hippel-Lindau-related hemangioblastomas, and promising results have been reported with ONC201 in diffuse midline glioma H3-K27M altered.

Understanding metastatic involvement of the conus medullaris: a systematic review of clinical presentations, diagnostic approaches, treatment options, and patient outcomes.

INTRODUCTION: Metastasis to the conus medullaris (CM) is a rare but devastating condition. This systematic review aimed to evaluate the clinical presentation, diagnostic workup, treatment options, and outcomes of patients with CM metastasis. By synthesizing the available evidence, this study seeks to improve our understanding of this condition and inform clinical practice. MATERIALS AND METHODS: A systematic review adhering to PRISMA guidelines analyzed literature on CM metastasis from 1997 to January 2024. Human studies in English were included, focusing on primary research articles. Screening criteria ensured a homogeneous study population, with data analyzed using SPSS 26 and assessed for quality using the JBI checklist. RESULTS: The study analyzed 88 patients with conus medullaris metastasis. Common symptoms included back pain (49.3%), sensory impairment (75%), and bladder dysfunction (60.3%). MRI was the primary diagnostic tool, revealing lesions above L1 (37%) or between L1 and L2 (29%). Treatment involved surgery with laminectomy, and combined therapy (surgery plus radiotherapy) in 81.3%. Postoperative outcomes showed improved motor function in 59.6% of patients, while combined therapy yielded better sensory and bowel/bladder function recovery. Median survival was 100 days. CONCLUSION: Metastasis to the conus medullaris is rare but significant. Surgical resection can improve motor function, while combined therapy (surgery plus radiotherapy) is effective in improving sensory manifestations and bowel/bladder functions. Despite these treatments, the median survival remains around 100 days, which is shorter compared to other types of intramedullary spinal cord metastases.

Understanding spinal cord astrocytoma: Molecular mechanism, therapy, and comprehensive management.

Spinal cord astrocytoma is a rare and highly debilitating tumor, yet our knowledge of its clinical characteristics, molecular features, and pathogenesis remains limited compared to that of its counterparts in the brain. Current diagnostic and therapeutic approaches for spinal cord astrocytomas are primarily based on established guidelines for brain astrocytomas. However, recent studies have revealed unique clinical and pathological attributes that distinguish spinal cord astrocytomas from their corresponding brain counterparts. These findings underscore the inadequacy of directly applying the clinical guidelines developed for brain astrocytomas to spinal astrocytomas. In this review, we provided an up-to-date overview of the advancements in understanding spinal cord astrocytomas. We also discussed the challenges and future research prospects in this field with the aim of improving the precision of diagnosis and therapy for these tumors. Specifically, we emphasized the importance of enhancing our understanding of the molecular heterogeneity, immune characteristics, and clinical trials of spinal cord astrocytomas.

State-of-the-Art and New Treatment Approaches for Spinal Cord Tumors.

Spinal cord tumors, though rare, present formidable challenges in clinical management due to their intricate nature. Traditional treatment modalities like surgery, radiation therapy, and chemotherapy have been the mainstay for managing these tumors. However, despite significant advancements, challenges persist, including the limitations of surgical resection and the potential side effects associated with radiation therapy. In response to these limitations, a wave of innovative approaches is reshaping the treatment landscape for spinal cord tumors. Advancements in gene therapy, immunotherapy, and targeted therapy are offering groundbreaking possibilities. Gene therapy holds the potential to modify the genes responsible for tumor growth, while immunotherapy harnesses the body's own immune system to fight cancer cells. Targeted therapy aims to strike a specific vulnerability within the tumor cells, offering a more precise and potentially less toxic approach. Additionally, novel surgical adjuncts are being explored to improve visualization and minimize damage to surrounding healthy tissue during tumor removal. These developments pave the way for a future of personalized medicine for spinal cord tumors. By delving deeper into the molecular makeup of individual tumors, doctors can tailor treatment strategies to target specific mutations and vulnerabilities. This personalized approach offers the potential for more effective interventions with fewer side effects, ultimately leading to improved patient outcomes and a better quality of life. This evolving landscape of spinal cord tumor management signifies the crucial integration of established and innovative strategies to create a brighter future for patients battling this complex condition.

Evaluation of surgically treated primary spinal cord tumors in a single Indian institution: A case series study of 178 patients.

Introduction: Primary spinal cord tumors are rare tumors that are usually heterogeneous having variable histopathological subtypes. Rapidly, growing space-occupying lesions in the spinal canal cause severe loss of function. This study aimed to analyze all adult patients diagnosed with primary spinal cord tumors and to describe their location, symptoms, histopathological types, surgical outcome, complications, recurrence in a single institution, and prognostic factors. Materials and Methods: The study was a retrospective study of 178 patients with spinal tumor who underwent surgical intervention at the department of neurosurgery at a tertiary care institute from 2014 to 2021. Patient demographic characteristics, symptoms, radiological features, spinal level of tumor, spinal compartment, preoperative and postoperative McCormick grade, and complications were recorded, and a comparison of outcomes after surgical intervention was done. Results: In our study, 97 patients were males and the rest of the 81 patients were females. The mean age at the time of surgery was 43.5 years. The thoracic region of the spinal canal was the most involved with 67 (37.64%) cases, whereas intradural extramedullary was the most common (65.73%). Schwannoma was the most common histopathological subtype (46.06%). Total excision was achieved in 154 cases. A total of 37 patients were in Grades 4 and 5 of modified McCormick's grade preoperatively. However, postoperatively, there were only 17 patients in this group. Two patients with cervical intramedullary tumor expired in the postoperative period. Conclusion: Early surgical intervention with sound microneurosurgical skills gives good outcomes independent of the type and location of tumor. Better outcomes are seen in extradural tumors, early surgical intervention, tumors better amenable to total resection, and in patients with better preoperative neurological status.

Mexican Multicenter Experience of Metastatic Spinal Disease.

Background Spinal metastatic disease is a silent progressive cancer complication with an increasing prevalence worldwide. The spine is the third most common site where solid tumors metastasize. Complications involved in spinal metastasis include root or spinal cord compression, progressing to a declining quality of life as patient autonomy reduces and pain increases. The main objective of this study is to report the incidence of patients and typology of spinal metastases in three reference centers in Mexico. Methodology Retrospective cohorts of patients diagnosed with spinal metastases from January 2010 to February 2017 at the National Cancer Institute, National Rehabilitation Institute, and the Traumatology and Orthopedics Hospital "Lomas Verdes" in Mexico City were analyzed. Results A total of 326 patients (56% males) with spinal metastases were reported. The mean age was 58.06 ± 14.05 years. The main sources of spinal metastases were tumors of unknown origin in 53 (16.25%) cases, breast cancer in 67 (20.5%) cases, prostate cancer in 59 (18%) cases, myeloma in 24 (7.4%) cases, and lung cancer in 23 (7.1%) cases. Conclusions The data obtained in this analysis delivers an updated standpoint on Mexico, providing the opportunity to distinguish the current data from global references. Collecting more epidemiological information for better recording of cancer and its associated complications, as well as further studies on them, is necessary.

The pons as an optimal background reference region for spinal 18F-FET PET/MRI evaluation.

BACKGROUND: This study aims to evaluate the effect of various background reference regions on spinal 18F-FET PET imaging, with a focus on distinguishing between spinal tumors and myelitis. To enhance diagnostic accuracy, we investigated the pons and several other spinal cord area as potential references, given the challenges in interpreting spinal PET results. RESULTS: A retrospective analysis was conducted on 30 patients, 15 with cervical myelitis and 15 with cervical tumors, who underwent O-(2-[18F]-fluoroethyl)-L-tyrosine (FET) PET/MR imaging. The stability of uptake across four regions, including the pons, C2, C2-C7, and T1-T3, was compared. The standardized uptake value ratio (SUVR) was then evaluated using various background regions, and their effectiveness in differentiating between spinal tumors and myelitis was compared. Additionally, we correlated the SUVR values derived from these regions with the Ki-67 proliferation index in tumor patients. The study found no significant difference in SUVmax (U = 110, p = 0.93) and SUVmean (U = 89, p = 0.35) values at lesion sites between myelitis and tumor patients. The pons had the highest average uptake (p < 0.001) compared to the other three regions. However, its coefficient of variation (CV) was significantly lower than that of the C2-C7 (p < 0.0001) and T1-T3 segments (p < 0.05). The SUVRmax values, calculated using the regions of pons, C2-C7 and T1-T3, were found to significantly differentiate between tumors and myelitis (p < 0.05). However, only the pons-based SUVRmean was able to significantly distinguish between the two groups (p < 0.05). Additionally, the pons-based SUVRmax (r = 0.63, p = 0.013) and SUVRmean (r = 0.67, p = 0.007) demonstrated a significant positive correlation with the Ki-67 index. CONCLUSIONS: This study suggests that the pons may be considered a suitable reference region for spinal 18F-FET PET imaging, which can improve the differentiation between spinal tumors and myelitis. The significant correlation between pons-based SUVR values and the Ki-67 index further highlights the potential of this approach in assessing tumor cell proliferation.

Demographic and clinical data of patients with spinal epidural angiolipomas.

Spinal epidural angiolipomas are rare, benign, mesenchymal tumors. It remains unclear whether spinal epidural angiolipomas are genuinely rare or merely underreported. Herein, we assessed the demographic and clinical characteristics of patients with spinal epidural angiolipoma. We collected data from patients with spinal epidural angiolipoma from three sources. First, we retrospectively analyzed data from patients diagnosed with spinal epidural angiolipoma in our hospital between January 1, 2014, and December 31, 2023. Second, we performed a literature review of studies retrieved from PubMed. Third, we retrieved detailed data of patients with spinal angiolipoma from the Surveillance, Epidemiology, and End Results (SEER) database. We conducted a descriptive analysis to investigate the demographic and clinical characteristics of patients with spinal epidural angiolipoma. At our institution, three patients were diagnosed with spinal epidural angiolipoma. Additionally, we identified 116 patients from the literature review and 15 patients from the SEER database. We reviewed the treatment history and imaging features of the three patients from our institution. The descriptive analysis of the data collected from the literature review was consistent with previous reports. For example, 63.0% of lesions were located at the thoracic level. 31.9% of these lesions involved two vertebral bodies, while 75.6% involved 2-4 vertebral bodies. The most common symptoms experienced by patients were back pain, paraparesis, and numbness in the legs. Surgery was the primary treatment option for most patients, and complete tumor resection was achieved in the majority of patients. The male:female ratio was 1:1.4, the median age at diagnosis for the patients from the literature was 49 years old, and the median follow-up was 24 months. Notably, most of the reports came from Asia and there were few reports from Africa. The findings from the SEER database indicated a male:female ratio of 2:1. The peak incidence, which is typically reported in the fifth decade of life, was not observed. We presented three cases of spinal epidural angiolipoma and supplemented our findings with a literature review and population-based analysis according to the SEER database for the United States population. We believe that our research will enhance clinicians' comprehension of this uncommon tumor.

Diagnostic Accuracy of Somatosensory Evoked Potential and Transcranial Motor Evoked Potential in Detection of Neurological Injury in Intradural Extramedullary Spinal Cord Tumor Surgeries: A Short-Term Follow-Up Prospective Interventional Study Experience from Tertiary Care Center of India.

Objective Intraoperative neuromonitoring (IONM) is an acknowledged tool for real-time neuraxis assessment during surgery. Somatosensory evoked potential (SSEP) and transcranial motor evoked potential (MEP) are commonest deployed modalities of IONM. Role of SSEP and MEP in intradural extramedullary spinal cord tumor (IDEMSCT) surgery is not well established. The aim of this study was to evaluate sensitivity, specificity, positive predictive value, negative predictive value, and diagnostic accuracy of SSEP and transcranial MEP, in detection of intraoperative neurological injury in IDEMSCT patients as well as their postoperative limb-specific neurological improvement assessment at fixed intervals till 30 days. Materials and Methods Symptomatic patients with IDEMSCTs were selected according to the inclusion criteria of study protocol. On modified McCormick (mMC) scale, their sensory-motor deficit was assessed both preoperatively and postoperatively. Surgery was done under SSEP and MEP (transcranial) monitoring using appropriate anesthetic agents. Gross total/subtotal resection of tumor was achieved as per IONM warning alarms. Sensitivity, specificity, positive predictive value, negative predictive value, and diagnostic accuracy of SSEP and MEP were calculated considering postoperative neurological changes as "reference standard." Patients were followed up at postoperative day (POD) 0, 1, 7, and 30 for convalescence. Statistical Analysis With appropriate tests of significance, statistical analysis was carried out. Receiver-operating characteristic curve was used to find cutoff point of mMC for SSEP being recordable in patients with higher neurological deficit along with calculation of sensitivity, specificity, positive predictive value, negative predictive value, and diagnostic accuracy of SSEP and MEP for prediction of intraoperative neurological injury. Results Study included 32 patients. Baseline mean mMC value was 2.59. Under neuromonitoring, gross total resection of IDEMSCT was achieved in 87.5% patients. SSEP was recordable in subset of patients with mMC value less than or equal to 2 with diagnostic accuracy of 100%. MEP was recordable in all patients and it had 96.88% diagnostic accuracy. Statistically significant neurological improvement was noted at POD-7 and POD-30 follow-up. Conclusion SSEP and MEP individually carry high diagnostic accuracy in detection of intraoperative neurological injuries in patients undergoing IDEMSCT surgery. MEP continues to monitor the neuraxis, even in those subsets of patients where SSEP fails to record.

Nondysraphic intramedullary spinal cord lipoma: a case report.

Introduction: Intramedullary nondysraphic spinal lipomas are extremely rare among primary spinal cord tumors. These patients present with nonspecific sensory symptoms followed by deterioration of motor symptoms. As the safety margins for neurological preservation are thin, meticulously locating the extent of the tumor and choosing the resection modalities is essential. Case report: The authors report a rare case of a 35-year-old male who presented with progressive difficulty in walking for 6 months associated with numbness and tingling sensation in the bilateral upper and lower limbs. He was diagnosed with nondysraphic intramedullary cervicothoracic lipoma and underwent subtotal resection of the tumor. Conclusion: Nondysraphic intramedullary spinal cord lipomas are rare and may present as nonspecific neurological symptoms. Hence, they should be considered differentials of intramedullary spinal cord tumors. Surgery appears to be the mainstay of treatment.

Diffusion Tensor Imaging Identifies Cervical Spondylosis, Myelitis, and Spinal Cord Tumors.

BACKGROUND: Diffusion tensor imaging (DTI) has been increasingly recognized for its capability to study microstructural changes in the neuropathology of brain diseases. However, the optimal DTI metric and its diagnostic utility for a variety of spinal cord diseases are still under investigation. PURPOSE: To evaluate the diagnostic efficacy of DTI metrics for differentiating between cervical spondylosis, myelitis, and spinal tumors. METHODS: This retrospective study analyzed DTI scans from 68 patients (22 with cervical spondylosis, 23 with myelitis, and 23 with spinal tumors). DTI indicators, including fractional anisotropy (FA), mean diffusivity (MD), radial diffusivity (RD) and axial diffusivity (AD), were calculated. The Kruskal-Wallis test was used to compare these indicators, followed by Receiver Operating Characteristic (ROC) curve analysis, to evaluate the diagnostic efficacy of each indicator across disease pairs. Additionally, we explored the correlations of DTI indicators with specific clinical measurements. RESULTS: FA values were significantly lower in tumor patients compared to those with cervical spondylosis (p < 0.0001) and myelitis (p < 0.05). Additionally, tumor patients exhibited significantly elevated MD and RD values relative to the spondylosis and myelitis groups. ROC curve analysis underscored FA's superior discriminative performance, with an area under the curve (AUC) of 0.902 for differentiating tumors from cervical spondylosis, and an AUC of 0.748 for distinguishing cervical myelitis from spondylosis. Furthermore, a significant negative correlation was observed between FA values and Expanded Disability Status Scores (EDSSs) in myelitis patients (r = -0.62, p = 0.002), as well as between FA values and Ki-67 scores in tumor patients (r = -0.71, p = 0.0002). CONCLUSION: DTI indicators, especially FA, have the potential in distinguishing spondylosis, myelitis, and spinal cord tumors. The significant correlation between FA values and clinical indicators highlights the value of FA in the clinical assessment and prognosis of spinal diseases and may be applied in diagnostic protocols in the future.

The Impact of Neurophysiological Monitoring during Intradural Spinal Tumor Surgery.

Surgery for spinal cord tumors poses a significant challenge due to the inherent risk of neurological deterioration. Despite being performed at numerous centers, there is an ongoing debate regarding the efficacy of pre- and intraoperative neurophysiological investigations in detecting and preventing neurological lesions. This study begins by providing a comprehensive review of the neurophysiological techniques commonly employed in this context. Subsequently, we present findings from a cohort of 67 patients who underwent surgery for intradural tumors. These patients underwent preoperative and intraoperative multimodal somatosensory evoked potentials (SSEPs) and motor evoked potentials (MEPs), with clinical evaluation conducted three months postoperatively. The study aimed to evaluate the neurophysiological, clinical, and radiological factors associated with neurological outcomes. In univariate analysis, preoperative and intraoperative potential alterations, tumor size, and ependymoma-type histology were linked to the risk of worsening neurological condition. In multivariate analysis, only preoperative and intraoperative neurophysiological abnormalities remained significantly associated with such neurological deterioration. Interestingly, transient alterations in intraoperative MEPs and SSEPs did not pose a risk of neurological deterioration. The machine learning model we utilized demonstrated the possibility of predicting clinical outcome, achieving 84% accuracy.

The application value and improved warning criterion of D-wave monitoring in intramedullary spinal cord tumor surgery.

BACKGROUND CONTEXT: The primary treatment method for intramedullary spinal cord tumor (IMSCT) is surgical resection, but this procedure carries a significant risk of neurological damage. Intraoperative neurophysiological monitoring (IONM) has become a necessary adjunctive tool for IMSCT resection. PURPOSE: The current study aimed to explore the application value of D-wave monitoring in IMSCT surgery, and tried to investigate a tailored criterion for its early warning. STUDY DESIGN: A retrospective clinical study. PATIENT SAMPLE: A retrospective analysis was conducted based on the data of patients who underwent IMSCT surgeries performed by the same neurosurgical team at our hospital. IONM was applied in all surgeries. According to inclusion and exclusion criteria, ultimately 90 patients were enrolled in the study. OUTCOME MEASURES: The McCormick Scale (MMS) was applied to assess the functional outcome through outpatient visits or telephone follow-up at one month and six months postoperatively. Patients with an MMS grade over II one month after surgery were considered to have newly developed postoperative motor dysfunction (PMD). If the MMS grade could be restored to I or II six months after surgery, it was defined as a short-term PMD. Otherwise, it was defined as a long-term PMD. METHODS: The predictive value of different IONM modalities, including somatosensory evoked potential (SEP), muscle motor evoked potential (MEP), and D-wave for PMD, was assessed with sensitivity, specificity, positive predictive value, negative predictive value, and subsequent logistic regression analysis. At last, the cut-off value of the D-wave amplitude reduction ratio for predicting PMD was obtained through the receiver operating characteristic (ROC) curve analysis. RESULTS: SEP showed the worst performance in predicting short-term and long-term PMD. Significant MEP changes were indicated as an independent predictive factor for short-term PMD (OR 5.062, 95% CI 1.947-13.166, p=.001), while D-wave changes were demonstrated as an independent predictor for long-term PMD (OR 339.433, 95% CI 11.337-10770.311, p=.001). The optimum cut-off value of the D-wave amplitude reduction ratio for predicting long-term PMD was 42.18%, with a sensitivity of 100% and a specificity of 93.8% (AUC=0.981, p<.001). CONCLUSIONS: D-wave monitoring showed extremely high specificity in predicting PMD compared to SEP and MEP monitoring. Moreover, the authors suggested that a D-wave amplitude reduction of over 40% during IMSCT surgery generally indicates long-term PMD for patients.

Radiological characterization of pediatric intramedullary astrocytomas: Do they differ from adults?

Introduction: The incidence of intramedullary spinal cord tumors ranges from 2 to 4% of all central nervous system tumors. Only 6-8% are astrocytomas. The gold standard to diagnose a spinal cord tumor is the spinal cord MRI in toto. Specific radiological criteria orient the diagnosis of the intradural intramedullary lesion. Most of the authors studied adult populations of astrocytomas. However, pediatric astrocytomas present certain particularities. Research question: This work aims to determine if the usual radiological criteria of intramedullary astrocytomas (IMAs) are different depending on the patient's age. Material & methods: We evaluated the radiological features of IMAs in adult and pediatric groups through a retrospective study. Results: We collected 31 patients with IMAs (11 children and 20 adults). We observed some trends but we did not highlight any statistically significant difference between all the radiological criteria studied (sagittal and axial spinal cord localization, T1-and T2-weighted characteristics, contrast uptake, infiltrating character, presence of necrosis, heterogeneous lesion, necrotic, hemorrhagic, presence of edema) and the patient's age. Discussion & conclusion: Given the rarity of IMAs and the lack of large specific pediatric studies, it seems essential to routinely report all cases encountered and create multicentric pediatric databases to draw more robust conclusions.

Intramedullary spinal cord tumors in pediatric patients presenting later with brain lesions: case series and systematic review of the literature.

PURPOSE: Intramedullary spinal cord tumors are an uncommon pathology in adults and children. Most descriptive studies of intramedullary spinal cord tumors have not focused on a possible association with future brain lesions. To the best of our knowledge, few reports describe this potential relationship. This is one of the most extensive case series of secondary brain lesions of intramedullary spinal cord tumors in the pediatric population. METHODS: Retrospective chart review was performed on pediatric patients (21 years old and younger) who underwent resection of an intramedullary spinal cord tumor at two tertiary care hospitals from 2001 to 2020. Patients previously treated or diagnosed with spinal cord tumor, and subsequent development of intracranial manifestation of the same or different tumor, were included. Data regarding epidemiology, surgical intervention, and clinical and follow-up course were gathered. Data analysis was performed according to a standardized clinical protocol with a literature review. RESULT: More than 500 patients underwent intradural spinal tumor resection surgeries at participating hospitals from 2001 to 2020. After excluding adult patients (older than 21 years old) and those with extramedullary lesions, 103 pediatric patients were identified who underwent resection of an intramedullary spinal cord tumor. Four underwent resection of an intermedullary tumor and later in their follow-up course developed a secondary intracranial neoplasm. In every case, the secondary neoplasm had the same pathology as the intramedullary tumor. Three of the patients had tumors at the cervico-thoracic junction, and one patient had a high cervical tumor. These patients had a negative primary workup for any metastatic disease at the time of the presentation or diagnosis. Complete and near complete resection was performed in three patients and subtotal in one patient. CONCLUSION: Secondary brain tumors disseminated after initial spinal cord tumor are extremely rare. This study aims to allow specialists to better understand these pathologies and treat these rare tumors with more certainty and better expectations of unusual associated lesions and conditions.