Filum Research Articles

Tethered cord syndrome in an adult with filum terminale lipoma: A case report

Background: Filum terminale lipomas (FTLs) are congenital lumbosacral anomalies that can cause tethered cord syndrome (TCS). Most patients with TCS caused by FTL are children, and these are only rarely present in adults. Case Description: A 64-year-old male presented with long-standing bilateral lower-limb weakness and bladder dysfunction. The lumbar magnetic resonance imaging revealed an FTL of the conus, which was not displaced. Following sectioning, the patient’s bilateral lower limb weakness resolved, and his bladder function improved. Conclusion: TCS caused by an FTL in late middle-aged patients is rare. After undergoing untethering with resection of the lipoma, the patient sustained resolution of his motor deficit and improvement in his bladder function.

Do Not Forget the Spine MRI in Children With Arthrogryposis Multiplex Congenita: High Prevalence of Tethered Spinal Cord and Preliminary Clinical Findings Following Detethering.

Arthrogryposis multiplex congenita (AMC) encompasses congenital conditions with joint contractures in 2 or more joints. Patients with AMC may have scoliosis and neural axis malformations. The study aimed to determine the prevalence of tethered spinal cord (TSC), characterized by a low-lying conus medullaris, and secondarily, present preliminary findings following surgical untethering in children with AMC. Patients 18 years of age and younger with a diagnosis of AMC and a spine MRI were identified. The presence of a TSC was defined as a low-lying conus with termination at or below the lower third of the L2 vertebral body. A pediatric neurosurgeon and a pediatric orthopaedic surgeon independently reviewed MRIs. The medical records of patients with AMC who underwent untethering were examined to evaluate preoperative and postoperative clinical findings. The prevalence of TSC in our AMC patients was compared with published normative data using χ2 analysis. Forty-two of 105 AMC patients (40%) had TSCs. There was a greater percentage of patients with AMC and a TSC compared with the unaffected population (P<0.0001). Sixteen patients underwent detethering through filum terminale sectioning. Nine patients had preoperative neurological deficits in addition to their AMC. There were no postoperative complications. All patients had improvement in their bowel and bladder symptoms within 3 months after their detethering procedure. TSC is more prevalent in the pediatric population with AMC compared with those without AMC. MRI is recommended for all patients with AMC due to its high prevalence. Although not a benign procedure, surgical detethering may have potential benefits for children with AMC. Level IV-therapeutic study.

SPIN-02 AN INTRAMEDULLARY MYXOPAPILLARY EPENDYMOMA: A RARE OCCURANCE IN THE CERVICO-THORACIC SPINE

Abstract BACKGROUND Spinal myxopapillary ependymomas are a rare variant of spinal ependymoma that are considered to occur exclusively in the conus medullaris and filum terminale. They account for about 13% of all spinal ependymomas and have a slight male predominance. Case presentation: We report a case of 38-year-old male, Muganda, that presented at the Neurosurgery department Mulago National Referral Hospital with progressive paresthesia and paraparesis, of the upper limbs and chronic neck pain for 2years. MRI showed an isointense lesion on TIWI extending from C4 to T2 levels and exhibited heterogenous enhancement on gadolinium administration. The lesion was hyperintense on T2WI with a syrinx above the tumor. A radiological diagnosis of an intramedullary neoplastic process was made with differentials of Ependymoma, Schwanomma, and Astrocytoma. The patient underwent posterior laminectomy, and the tumor was completely excised. He is currently under follow up by the Neurosurgery team. CONCLUSION This case underscores the rarity of intramedullary myxopapillary ependymomas highlighting diagnostic challenges and the critical role of tailored surgical interventions in managing rare spinal neoplasms.

Predictors of postsurgical retethering in pediatric fatty or tight filum terminale: a systematic review and meta-analysis of 1167 patients.

The objective of this study was to characterize pediatric patients with tight filum terminale (TFT) or fatty filum terminale (FFT) who experienced retethering after transection of the filum, and to determine the risk factors for retethering. A systematic review was conducted on May 31, 2023, using PubMed, Google Scholar, SCOPUS, and Web of Science databases according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines to identify studies detailing retethering following transection for TFT or FFT. Studies were then screened using the Newcastle-Ottawa Scale for risk of bias assessment. Eleven articles met the inclusion criteria with an overall cohort of 1167 patients evaluated for retethering following transection for TFT or FFT. The combined retethering rate across all retrospective studies was 3.4% (95% CI 1.6%-5.2%). A random-effects model was used to estimate the prevalence of presenting symptoms, with the most common being lower-extremity weakness in the overall cohort (54.5%, 95% CI 32.6%-76.4%) and bowel or bladder dysfunction in the retethered cohort (57.9%, 95% CI 41.1%-74.8%). Patients who experienced retethering had a similar estimated prevalence of low-lying conus (71.1%, 95% CI 45.1%-97.1%) compared with the overall cohort (51.1%, 95% CI 39.3%-63.0%). The most common complication following surgery for the overall cohort was a wound complication (2.7%, 95% CI 0.8%-4.6%). Postoperative CSF leakage (OR 13.8, 95% CI 3.9-49.4) was a strong predictor of retethering. Sensory changes at initial presentation were also found to be a predictor of retethering (OR 2.9, 95% CI 1.3-6.5). Low-lying conus was not predictive of retethering. Preoperative sensory changes and postsurgical CSF leakage were associated with an increased retethering rate following transection of the filum in cases of tethered cord syndrome secondary to fatty filum terminale.

Clinicoradiological, pathological, and surgical outcome in patients with tethered cord syndrome: A prospective study

Background: Tethered cord syndrome (TCS) is a stretch-induced functional disorder of the spinal cord in which the caudal part is anchored by an inelastic structure. It is believed that, if the viscoelasticity of the filum is lost or compromised by either fatty infiltration or abnormal thickening, caudal tension and traction may cause undue stress upon the conus, resulting in TCS. It typically occurs in children, and it is rare in adults. Aims and Objectives: The study was conducted to know the clinicoradiological, pathological, and surgical outcomes in patients with TCS. Materials and Methods: This is a prospective observational study done in the premier institute of central India from May 2022 to April 2024. This study included patients who exhibited clinical and/or radiological features of congenital tethered cords. This encompassed both patients with tethered cord and those with TCS. Patients who failed to give consent and refused to participate in the study were excluded from the study. Results: A total of 30 patients were recruited for the study. The median age of the patients was 6–12 months (range). The gender distribution M:F was 63.3:36.6. Based on 30 cases studied, most of the patients (75%) had improvement in urinary symptoms, 57.1% of patients had improvement in bowel symptoms, 80% of patients had improvement in pain symptoms, 75% had improvement in motor deficit, and 83.3% had improvement in sensory deficit. Conclusion: Our prospective, cross-sectional study aimed at complete detethering of the spinal cord and the nerve roots along with excision of filum terminale and dural reconstruction to maintain adequate cerebrospinal fluid space around the spinal cord to prevent retethering.

Filum terminale infected epidermoid cysts in pediatric age group; A case series

BackgroundEpidermoid cysts are rare and account for only 1 % of primary spinal tumors. It's due to inclusion of ectodermal tissue during the third and fourth weeks of gestation. Infected epidermoid cysts are exceedingly rare with very few reports in literature. The clinical presentations include radicular symptoms, motor weakness, sphincteric disturbance, and repeated chemical meningitis. Surgery of this kind of tumor remained a challenge and of a considerable recurrence rate. MethodsThis is a retrospective study reviewing the records of six children who were treated for filum terminale infected epidermoid cysts. All patients underwent microsurgery, and the surgical outcomes were studied through a follow up period of at least 24 months. ResultsAll children had a low back dermal sinus with purulent discharge. One child was a recurrent presentation after the previous two surgeries for evacuation of pus collection, and the other five children were operated for the first time. All the six children had an associated neurological deficit; one child presented with active central nervous system infection, and one child had a history of meningitis and admission to hospital prior to our surgery. Regular follow up revealed no recurrence in any of the six patients. The five patients, who presented with motor weakness, showed significant improvement of the motor power with regular post-operative physical therapy. ConclusionEpidermoid cysts are rare benign lesions that may lead to significant morbidity when infected. The aim of microsurgical excision is to remove the cyst content and its capsule without inducing or increasing neurological deficit by the aid of intraoperative neuromonitoring and microsurgery techniques.

Incidence of Tethered Cord Syndrome in Pediatric Patients With Neurofibromatosis Type 1

ObjectiveThe link between Tethered Cord Syndrome (TCS) and Neurofibromatosis Type 1 (NF1) remains unclear. To date, only two studies have indicated a high occurrence of TCS in the pediatric NF1 patient population. Our study aims to ascertain the incidence of TCS among Chinese pediatric patients with NF1. MethodsA single-institution, 8-year retrospective analysis at a tertiary-level children's hospital was conducted for patients with NF1 who underwent surgery for TCS. The clinical features, imaging characteristics, genetic testing outcomes, and histopathological findings of pediatric NF1 patients with TCS were analyzed. ResultsDuring the study period, a total of 115 pediatric patients were diagnosed with NF1. Among these 115 NF1 patients, 11 individuals, accounting for 9.6% of the sample, were confirmed to have TCS. This rate of occurrence is significantly higher than the incidence rate of TCS in the general population, which stands at 0.17%. All 11 of the pediatric NF1 patients underwent surgery for TCS. Out of the 11 patients who were advised to have tethered cord release surgery, 4 (which is 36.4%) were girls, and the average age of these 11 patients was 8.6 years old, with ages ranging from 2 to 17 years old. The conus medullaris position of the 11 pediatric NF1 patients ranged from L1 to L2, and 10 of them (91%) had a filum terminale lipoma, characterized by high signal intensity on T1-weighted magnetic resonance (MR) images. Another patient was diagnosed with Occult Tethered Cord Syndrome (OTCS). All 11 pediatric NF1 patients exhibited symptoms associated with TCS, such as neuromotor dysfunction, abnormalities in urination, defecation, skeletal system abnormalities, or pain. Eight of the 11 pediatric NF1 patients had undergone genetic testing, which is a crucial part of the diagnostic process for NF1. The histopathological examination of the 11 pediatric NF1 patients who underwent surgery revealed that 10 patients had fatty infiltration of the filum terminale (FT), while the remaining patient exhibited fibrosis of the filum terminale (FT). ConclusionsIn the group of pediatric patients with NF1, the incidence of TCS, presenting to the pediatric neurosurgery clinic for any reason, is significantly higher than that of the general population. However, the pathophysiological relationship between NF1 and TCS is still not clear. It is essential to provide counseling to NF1 patients and their families about the symptoms of TCS to make sure they are aware and can seek the necessary care when needed. This underscores the importance of not only diagnosing NF1 but also staying alert for related conditions like TCS, which may have a higher occurrence in this demographic.

Optimizing Therapeutic Strategies for Syringomyelia Associated with Tethered Cord Syndrome: A Comprehensive Review.

This review highlights the need for therapeutic guidelines for syringomyelia associated with tethered cord syndrome (TCS) caused by spinal dysraphism (SD). A comprehensive literature review was conducted, selecting twelve articles to analyze common therapeutic strategies. Surgical cord untethering alone has recently become a preferred treatment, with 45 ± 21.1% of patients experiencing remission or improvement, 47 ± 20.4% unchanged and asymptomatic, and 4 ± 8% worsened. Untethering with direct surgical drainage for the syrinx had better outcomes than untethering alone (78% vs. 45%, p = 0.05). Terminal syringostomy was beneficial for syrinxes extending to the filum terminale but not for asymptomatic small syrinxes with a syrinx index < 0.4. Syrinx shunting was recommended for symptomatic large syrinxes (>2 cm in length and syrinx index > 0.5). Various shunt procedures for syrinxes are still advocated, mainly for refractory syringomyelia in Chiari malformation, posttraumatic cases, SD, or other causes. Personalized surgical methods that address the root cause of syringomyelia, particularly those improving cerebrospinal fluid flow, offer promising results with minimized complications. Ongoing studies are required to enhance management strategies for syringomyelia associated with TCS, optimize patient outcomes, and reduce the risk of recurrent symptoms.

Surgical Outcomes in Patients Exhibiting Muscular Weakness Postadolescence Due to Tight Filum Terminale.

Tight filum terminale is a neurological condition marked by various symptoms, including muscle weakness. There is a notable lack of literature addressing muscle weakness, particularly in cases emerging during adolescence and beyond. The diagnosis is challenging due to a lack of radiological abnormalities, and the literature on its treatment, especially untethering, in adults is limited. This study aims to evaluate the effectiveness of untethering in improving muscle weakness and other symptoms in postadolescent patients diagnosed with tight filum terminale. A retrospective analysis was conducted on seven postadolescent patients diagnosed with tight filum terminale and presenting muscle weakness who underwent untethering at our institution between January 2018 and August 2022. Patients were monitored for muscle strength improvement, lumbar and lower extremity pain, and bowel and bladder dysfunction (BBD) after untethering. Muscle weakness improved in all cases after untethering, with a mean duration of 9.1 weeks for the improvement. Patients unable to walk independently regained mobility in an average of 22.3 weeks. Lumbar and lower limb pain improved in all cases within an average of 8.1 weeks, while BBD improved in six of the seven cases within an average of 1.9 weeks. Our findings suggest that untethering is an effective surgical intervention for postadolescent patients diagnosed with tight filum terminale and presenting muscle weakness.

Effect of Tethered Cord Release on Progression of Pediatric Scoliosis: A Systematic Review

Abstract Background Tethered cord syndrome is one of the intraspinal anomalies, caused by abnormal fixation of the spinal cord and classically result in low-lying and immobile conus medullaris. The incidence of TCS is estimated to be 0.05 to 0.25 per 1000 births. That abnormal fixation of the spinal cord may result from many causes, including intraspinal lipoma, lipomyelomeningocele, tight or thickened filum terminale, or scarring from previous myelomeningocele repair. Methodology All available studies concerning tethered cord associated with scoliosis and the progression rate of scoliosis after release of tethered cord including randomized controlled studies, cohort studies, and case series was reviewed in addition to the references of the included articles. Systematic reviews, technical notes, letters, and comments was excluded. Studies not written in English was excluded. Patients since birth up to 16 years old, patients with tethered cord associated with scoliosis. Results The current evaluation reveals that tethered cord release improve\stable the scoliosis angle by only 47% and 40% of patients required fusion despite the untethering, there are other factors affecting the progression such as riser grade and age. Conclusion Nevertheless, the lack of good quality evidence and scarcity of the literature on the topic was also propounded by this review. Prospective, randomised and multicentre RCT’s are required to establish the effect of this procedure on the progression of the deformity.

Comparison of the inter-laminar approach and laminotomy open approach for filum terminale lipoma: A retrospective analysis.

Filum terminale lipoma (FTL) causes spinal-cord tethering and is associated with tethered-cord syndrome, which is treated by dissection of the entrapment. The conventional treatment for FTL involves dissection of the spinal cord through a laminotomy open approach (LOA). However, in recent years, the interlaminar approach (ILA) has gained popularity as a minimally invasive surgery. This study compares the effectiveness of the minimally invasive ILA with the conventional LOA in treating FTL. We retrospectively evaluated data on the ILA and LOA for FTL at our center. In total, 103 participants were enrolled, including 55 in the ILA group and 48 in the LOA group. The ILA required significantly less surgical time and resulted in less blood loss. The improvement rate of symptoms in symptomatic patients was 84%, and for urinary symptoms and abnormal urodynamic study findings, it was 77%. The postoperative maintenance rate for asymptomatic patients was 100%. Postoperative complications of ILA included delayed wound healing in two patients (3.6%). Compared with LOA, ILA offers advantages in terms of shorter operative time and less blood loss, with no significant difference in long-term symptom-improvement rates between the groups.

171 Not Just a Matter of Retained Embryonic Spinal Cord: Histopathology of the Filum Terminale in Tethered Cord Syndrome

INTRODUCTION: We present a large consecutive series of patients with tethered cord syndrome who underwent resection of the filum terminale (FT) and the histopathologic findings as analyzed by the neuropathologists. METHODS: FT specimens obtained from a consecutive series of 288 pediatric and adult patients that underwent spinal cord releases performed at a single academic institution from 2013-2021 were analyzed retrospectively (IRB #787945). Hematoxylin and eosin (HE) and immunohistochemistry staining was performed to study the spectrum of cells known to reside in connective tissues. RESULTS: The most common structures included peripheral nerves (97.6%), ependymal cells (70.8%), ganglion cells (38.5%), and neuropil (15.3%). Cases with excess ependymal cells were associated with ependymal canals (5.9%), ependymal cysts (3.1%), and one case with extensive ependymal “proliferation” (0.3%). With regards to the inflammatory cellular findings, eleven specimens (3.8%) contained scattered or accumulated lymphocytes, macrophages, mast cells, macrophage-derived giant cells, and a secondary lymph follicle in one patient. 36 patients (12.5%) had increased vascularity with enlarged capillaries. Nine patients (3.1%) had an associated type of vascular malformation. A group of specimens included dystrophic calcification within the FT (7.6%). CONCLUSIONS: Both vascular and inflammatory changes along with calcifications have been overlooked as possible associated histologic secondary to mechanical stress on the FT. Additionally, vascular anomalies could alter the filum’s mechanical properties due to venous congestion.

Surgical management of tethered spinal cord syndrome through biportal endoscopic approach: a novel technical note.

This video article explores a case of tethered cord release through a minimally invasive biportal endoscopic approach. A 24-year-old female with chronic back pain and thigh numbness underwent surgery. The chosen approach involved biportal endoscopic technique, demonstrating precision with minimal bone excision. Preoperative imaging revealed a midline fusion defect at L5 and abnormal conus medullaris termination. The surgical procedure involved one-sided hemilaminectomy, durotomy, and careful filum terminale separation. Postoperatively, radiological exams confirmed success with minimal bone defect. Emphasizing minimal invasiveness, reduced bone excision, and muscle sparing, this technique showcased successful outcomes, enabling the patient's rapid postoperative recovery without complications. The video can be found here: https://stream.cadmore.media/r10.3171/2024.1.FOCVID23228.

Preliminary Experience with 3-Dimensional-Exoscopic Untethering of a Type II Diastematomyelia: Technical Note and Review of the Literature

ObjectiveThe aim of this paper is to describe the use of high-definition 3D exoscope (VITOM 3D exoscope - Karl Storz GmbH, Tuttlingen, Germany) for the neurosurgical treatment of a rare pediatric disease, type II diastematomyelia with associated tethered cord. MethodsA 13-year-old girl suffering diastematomyelia type II with a tethered cord was surgically treated with the aid of a high-definition 3D exoscope, with a third operator moving and pivoting its arm. Intraoperative monitoring and mapping was arranged. The surgery required a bilateral access to address both the split cord malformation and the tethering of the filum terminale. The filum terminale was identified and cut, and the connective fibrovascular tissue separating the two medullary halves were unraveled. These steps were performed with no changes of intraoperative monitoring. Pertinent literature has been carefully addressed ResultsThe surgery was successful, and the patient was discharged home on the eleventh postoperative day without any complications. The 3-month postoperative MRI demonstrated regular surgical outcomes; no dynamic motor disturbances were reported. To our knowledge this is the first spinal congenital malformation treated with the use of a 3D exoscope. ConclusionsThe use of 3D exoscope is advancing in spinal surgery, as it provides magnification, stereopsis, lighting and definition comparable to the operating microscope; the addition of a third operator simplified the operations of moving around the arm, releasing these burdens for the surgeons. Our preliminary experience proved that the use of a 3D exoscope is feasible and safe for surgical management of a type II diastematomyelia with tethered cord.

Tethered spinal cord syndrome associated with spina bifida: clinical and radiological characteristics and indications for surgery (systematic review of the literature)

Objective. To analyze literature data on clinical and radiation characteristics of the tethered spinal cord syndrome in spina bifida and to define criteria for indications for surgical treatment.Material and Methods. A search for prospective cohort clinical studies evaluating the clinical and radiation picture and indications for surgicalcorrection of the tethered spinal cord syndrome associated with spina bifida, published in 2005–2023 was performed in the Pubmed, EMBASE, eLibrary and the Сochrane Library databases. The literature search was carried out by one researcher. The study was carried out in accordance with the international recommendations for writing systematic reviews and meta-analyses PRISMA. The levels of evidencefor reliability and grades of the strength of recommendations were evaluated according to the ASCO Guidelines.Results. A total of 394 literature sources were found in the databases. Duplicate materials (n = 81) have been removed. When non-fulltext articles were excluded, only 28 out of 251 remained studies met the inclusion criteria and were analyzed. According to the level of evidence, 18 of them were classified as B level, and 10 – as C level.Conclusion. The components of the tethered spinal cord syndrome are a dystopic spinal cord cone, a shortened fixed filum terminale, and the presence of a lumbosacral lipoma. At the same time, there are currently no clear criteria for the integral assessment of the clinical and morphofunctional state of patients, and the available scales are not specific. The described MRI criteria are limited by the level of evidence, but despite this, they reflect a high level of consensus among experts, including that on the defining indications for surgical spinal corduntethering. The lack of clear indications for surgical intervention and the debatability of performing preventive untethering of the spinal cord require further study of the problem with an emphasis on analyzing the criteria for tethered spinal cord syndrome.

Results of Surgical Treatment of Occult Spinal Dysraphisms-A Single Centre Experience.

Occult spinal dysraphisms (OSDs) are caused by various defects in the embryogenesis of the spinal cord and represent an obstacle to the ascent of the conus, which allows the conus to pass from the lower levels of the spinal canal to the final position between L1 and L2 during normal foetal life. When an OSD tethers the spinal cord at the lower levels, it can lead to neurological symptoms, better known as tethered cord syndrome. Surgical treatment of OSD is primarily aimed at untethering the spinal cord. In asymptomatic patients, this can protect against the long-term development of neurological deficits. In symptomatic patients, this can halt or limit the progression of existing symptoms. The aim of this study is to examine all paediatric and adult patients diagnosed with OSD and treated in the Department of Neurosurgery at the University Medical Centre Ljubljana during the 5-year period of 2016-2021. All patients diagnosed with OSD during this period were included in the study. Patient characteristics, treatment modalities and outcomes were studied with the aim of describing the differences between the paediatric and adult population and defining the rationality of treating these pathological conditions. We included in the study 52 patients with 64 occult dysraphic lesions. Adults (>18 years old) represented 15/52 (28.8%) of all patients, while 37/52 (71.8%) were children. The most common OSDs were conus lipomas, followed by dermal sinus tracts, filum terminale lipomas and split cord malformations. Surgical treatment was performed in 35/52 (67.3%) cases, while conservative management was chosen in 17/52 (32.6%) cases. The preoperative presence of symptoms was statistically higher in adults than in children (p = 0.0098). Surgery on complex spinal cord lipomas was statistically related to a higher rate of postoperative neurological complications (p = 0.0002). The treatment of OSD is complex and must be based on knowledge of the developmental anomalies of the spine and spinal cord. Successful surgical treatment relies on microsurgical techniques and the use of neuromonitoring. Successful treatment can prevent or limit the occurrence of neurological problems.

Convolutional neural network-based magnetic resonance image differentiation of filum terminale ependymomas from schwannomas

PurposePreoperative diagnosis of filum terminale ependymomas (FTEs) versus schwannomas is difficult but essential for surgical planning and prognostic assessment. With the advancement of deep-learning approaches based on convolutional neural networks (CNNs), the aim of this study was to determine whether CNN-based interpretation of magnetic resonance (MR) images of these two tumours could be achieved.MethodsContrast-enhanced MRI data from 50 patients with primary FTE and 50 schwannomas in the lumbosacral spinal canal were retrospectively collected and used as training and internal validation datasets. The diagnostic accuracy of MRI was determined by consistency with postoperative histopathological examination. T1-weighted (T1-WI), T2-weighted (T2-WI) and contrast-enhanced T1-weighted (CE-T1) MR images of the sagittal plane containing the tumour mass were selected for analysis. For each sequence, patient MRI data were randomly allocated to 5 groups that further underwent fivefold cross-validation to evaluate the diagnostic efficacy of the CNN models. An additional 34 pairs of cases were used as an external test dataset to validate the CNN classifiers.ResultsAfter comparing multiple backbone CNN models, we developed a diagnostic system using Inception-v3. In the external test dataset, the per-examination combined sensitivities were 0.78 (0.71–0.84, 95% CI) based on T1-weighted images, 0.79 (0.72–0.84, 95% CI) for T2-weighted images, 0.88 (0.83–0.92, 95% CI) for CE-T1 images, and 0.88 (0.83–0.92, 95% CI) for all weighted images. The combined specificities were 0.72 based on T1-WI (0.66–0.78, 95% CI), 0.84 (0.78–0.89, 95% CI) based on T2-WI, 0.74 (0.67–0.80, 95% CI) for CE-T1, and 0.81 (0.76–0.86, 95% CI) for all weighted images. After all three MRI modalities were merged, the receiver operating characteristic (ROC) curve was calculated, and the area under the curve (AUC) was 0.93, with an accuracy of 0.87.ConclusionsCNN based MRI analysis has the potential to accurately differentiate ependymomas from schwannomas in the lumbar segment.

Incidence of tethered cord syndrome in neurofibromatosis types 1 and 2 pediatric patients: a population-level analysis.

Tethered spinal cord syndrome (TCS) is characterized by cutaneous attachments on the filum terminale that stretch the spinal cord, leading to musculoskeletal and urogenital sequelae. While the neurocutaneous associations with TCS remain undefined, a recent study reports a high incidence of TCS among a pediatric neurofibromatosis (NF) cohort. This present study utilizes a population-level database to estimate TCS incidence among pediatric patients with neurofibromatosis types 1 and 2 (NF1, NF2). The TriNetX Research Network was queried to identify patients diagnosed with NF and/or TCS before the age of 21. Symptomatic TCS requiring surgical intervention was identified using corresponding procedural codes within 12months following TCS diagnosis. Odds ratios (OR) were calculated to measure the associations of NF1/NF2 with TCS. 19,426 pediatric NF patients were evaluated (NF1: 18,383, NF2: 1042). The average ages of TCS diagnosis among NF1, NF2, and non-NF patients were 12, 16, and 9years, respectively. The incidence of TCS was 1.2% in NF1 patients and 7.3% in NF2 patients, compared to 0.074% in the general population. The associations of NF incidence with TCS were significantly increased in both NF1 (OR 16.42; 14.38-18.76) and NF2 (OR 105.58; 83.56-133.40) patients compared to the general population. Symptomatic TCS requiring surgical intervention was not significantly associated with NF1/NF2 patients compared to the general TCS population. This analysis demonstrates a high incidence of TCS but delayed intervention in pediatric NF patients. Considering TCS counseling, spinal MRI, and earlier intervention may be warranted for NF patients experiencing musculoskeletal symptomatology.

Clinical criteria for filum terminale resection in occult tethered cord syndrome.

Tethered cord syndrome (TCS) comprises three symptom categories: back/leg pain, bowel/bladder, and neurological complaints. MRI typically reveals a low-lying conus medullaris, filum terminale (FT) pathology, or lumbosacral abnormalities. FT resection is established in TCS but not in radiologically occult TCS (OTCS). This study aims to identify patients with OTCS who are likely to benefit from FT resection. The authors recruited 149 patients with OTCS (31 pediatric, 118 adult) treated with FT resection-including only cases with progressive TCS, negative spine MRI, and no concurrent neurological/urological conditions. A comprehensive questionnaire collected patient self-reported symptoms and clinical findings at the preoperative and at 3- and 12-month follow-up examinations. Based on questionnaire data, the authors extracted a 15-item symptoms and findings scale to represent the three TCS symptom categories, assigning 1 point for each item present. OTCS presents without radicular/segmental sensorimotor findings, but with leg/back pain and conus dysfunction, in addition to leg fatigue and spasticity; the latter indicating an upper motoneuron pathology. The 15-item scale showed clinical improvement in 89% of patients at the 3-month follow-up and 68% at the 12-month follow-up. Multivariate analysis of the scale revealed that it accurately predicts outcome of FT resection in 82% of cases. Patients with a preoperative score exceeding 6 points are most likely to benefit from surgery. By applying the study's inclusion criteria and incorporating the novel 15-item scale, surgeons can effectively select candidates for FT resection in patients with OTCS. The observed outcomes in these selected patients are comparable to those achieved in degenerative spine surgery.

The discrepancy in triggered electromyography responses between fatty filum and normal filum terminale

BackgroundFunctional role of filum terminale (FT) was not well studied though it contains structure basis for nerve impulse conduction. We aimed to explore the possible functions of the FT from the perspective of triggered electromyography (EMG) during surgery.MethodsWe retrospectively reviewed intraoperative neurophysiological monitoring data from pediatric patients who underwent intradural surgeries at the lumbar level in Shanghai Children’s. Hospital from January 2018 to March 2023. Altogether 168 cases with complete intraoperative neurophysiological recordings of the FT were selected for further analysis. Triggered EMG recordings of the filum originated from two main types of surgeries: selective dorsal rhizotomy (SDR) and fatty filum transection.Results96 cases underwent SDR and 72 cases underwent fatty filum transection. Electrical stimulation of the FT with fatty infiltration did not elicit electromyographic activity in the monitored muscles with the maximum stimulus intensity of 4.0 mA, while the average threshold for FT with normal appearance was 0.68 mA, and 89 out of 91 FT could elicit electromyographic responses in monitored channels. The threshold ratio of filum to motor nerve roots at the same surgical segment was significantly higher in patients with fatty filum, and a cut-off point of 21.03 yielded an area under curve of 0.943, with 100% sensitivity and 85.71% specificity.ConclusionFilum with normal appearance can elicit electromyographic activity in the lower limbs/anal sphincter similar to the performance of the cauda equina nerve roots. The threshold of fatty filum is different from that of normal appearing FT. Triggered EMG plays an important role in untethering surgeries.