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Objectives: Intraoperative ultrasonography (IOUS) offers the advantage of providing real-time imaging features, yet it is not generally used. This study aims to discuss the benefits of utilizing IOUS in spinal cord surgery and review related literature., Materials and Methods: Patients who underwent spinal cord surgery utilizing IOUS at a single institution were retrospectively collected and analyzed to evaluate the benefits derived from the use of IOUS., Results: A total of 43 consecutive patients were analyzed. Schwannoma was the most common tumor (35%), followed by cavernous angioma (23%) and ependymoma (16%). IOUS confirmed tumor extent and location before dura opening in 42 patients (97.7%). It was particularly helpful for myelotomy in deep-seated intramedullary lesions to minimize neural injury in 13 patients (31.0% of 42 patients). IOUS also detected residual or hidden lesions in 3 patients (7.0%) and verified the absence of hematoma post-tumor removal in 23 patients (53.5%). In 3 patients (7.0%), confirming no intradural lesions after removing extradural tumors avoided additional dural incisions. IOUS identified surrounding blood vessels and detected dural defects in one patient (2.3%) respectively., Conclusions: The IOUS can be a valuable tool for spinal cord surgery in identifying the exact location of the pathologic lesions, confirming the completeness of surgery, and minimizing the risk of neural and vascular injury in a real-time fashion., Competing Interests: All the authors confirmed no conflict of interest regarding this study., (Copyright: © 2024 Park et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)

Intramedullary spinal capillary hemangioma is a rare occurrence in pediatric patients, and only limited cases have been reported. This study presents the first two cases of spinal capillary hemangioma co-present with retained medullary cord and one case of spinal capillary hemangioma with lumbosacral lipomatous malformation. Previous literature on ten patients with this pathology was reviewed. We speculated pathogenesis, imaging features, and histopathologic findings of the disease., (© 2024. The Author(s).)

A 14-year-old boy presented with a 2-year history of slowly increasing weakness and atrophy in the right forearm and leg. Magnetic resonance imaging (MRI) revealed an intramedullary diffusely infiltrating lateralized tumor at C3-7. An extended biopsy was planned. After laminotomy and durotomy, the swollen spinal cord was noted to be rotated by 45° with the right dorsal root entry zone being in the midline. A 15 MHz linear ultrasound probe was used to identify the midline by visualizing the dorsal median sulcal vein within the midline raphe. A myelotomy was made in that zone without deterioration of somatosensory evoked potentials (SEPs) and an extended biopsy was performed. Histological examination revealed a pilocytic astrocytoma. Modern intraoperative high-resolution color-coded ultrasound enables the identification of the midline in intramedullary spinal cord lesions even when the spinal cord anatomy is distorted., (Copyright © 2024 The Author(s). Published by Elsevier Inc. All rights reserved.)

Summary: Surgical resection of intramedullary spinal cord tumors carries significant risks of neurologic deficits, especially in cases of infiltrative tumors. In pediatric patients, this type of surgery may be associated with a high risk of poor neurologic outcome. Intraoperative neurophysiologic monitoring has been adopted as part of the clinical routine by many centers as a useful adjunct for intraoperative assessment of neurologic integrity. To what extent intraoperative neurophysiologic mapping strategies may further support intraoperative decision-making is still a matter of debate. Here, we report on a small cohort of five pediatric patients in whom mapping with the double-train paradigm was used to identify the dorsal column and corticospinal tract and to guide the surgical resection. We also discuss the possible benefits and challenges regarding the available literature., Competing Interests: The authors have no funding or conflicts of interest to disclose., (Copyright © 2024 by the American Clinical Neurophysiology Society.)

Purpose: In surgery for intramedullary spinal cord tumors (imSCT), distortion of the anatomy challenges the visual identification of dorsal columns (DC) for midline myelotomy. Dorsal column mapping (DCM) and spinal cord stimulation (SCS) can identify DC neurophysiologically. We compare application and feasibility of both methods., Methods: Patients with surgically treated imSCT were prospectively included between 04/2017 and 06/2019. The anatomical midline (AM) was marked. SSEPs at the DC after stimulation of tibial/median nerve with an 8-channel DCM electrode and cortical SSEP phase reversal at C3/C4 after SCS using a bipolar concentric probe were recorded. Procedural and technical aspects were compared. Standardized neurological examinations were performed preoperatively, 1 week postoperatively and after more than 12 months., Results: The DCM electrode detected the midline in 9/13 patients with handling limitations in the remaining patients. SCS was applicable in all patients with determination of the midline in 9/13. If both recordings could be acquired (6/13), concordance was 100%. If baseline SSEPs were poor, both methods were limited. SCS was less time-consuming (p = 0.001), cheaper, and easier to handle. In 92% of cases, the AM and neurophysiologic midlines were concordant. After myelotomy, 3 patients experienced > 50% reduction in amplitude of SSEPs. Despite early postoperative worsening of DC function, long-term follow-up showed significant recovery and improvement in quality of life., Conclusion: DCM and SCS may help confirm and correct the AM for myelotomy in imSCT, leading to a favorable long-term neurological outcome in this cohort. SCS evolved to be superior concerning applicability, cost-effectiveness, and time expenditure., (© 2023. The Author(s).)

Introduction: Spinal cord surgery has and always will be a challenging operation with satisfying results, but also with potentially devastating results. Over the last century, there has been an evolution in the way we perceive and conduct spinal cord surgery. The phenomenal evolution in technology from the very first x-ray pictures helps to localize the spinal pathology through the use of high-resolution MRI and ultrasonography that allows for high precision surgery with relatively minimal exposure., Methods: The advancements in the surgical technique and the utilization of neuromonitoring allow for maximal safe resection of these delicate and intricate tumors. We also are beginning to understand the biology of spinal cord tumors and vascular lesions, as in the recent 2021 WHO classification which identifies specific entities such as spinal ependymomas, MYCN-amplified, as separate entity from the other subtypes of ependymomas. Surgeons have also accepted the importance of maximal safe resection for most of the spinal cord pathologies rather than just performing biopsy and adjuvant treatment., Conclusion: There have been significant advances since the first resection of an intramedullary tumor including diagnosis, imaging, and surgical technique for children. These advances have improved the prognosis and outcome in these children., (© 2023. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

The technical evolution of the surgery for spina bifida occulta (SBO) over the course of a half-century was reviewed with special foci placed on the spinal lipoma and tethered spinal cord. Looking back through history, SBO had been included in spina bifida (SB). Since the first surgery for spinal lipoma in the mid-nineteenth century, SBO has come to be recognized as an independent pathology in the early twentieth century. A half-century ago, the only option available for SB diagnosis was the plain X-ray, and pioneers of the time persevered in the field of surgery. The classification of spinal lipoma was first described in the early 1970s, and the concept of tethered spinal cord (TSC) was proposed in 1976. Surgical management of spinal lipoma with partial resection was the most widely practiced approach and was indicated only for symptomatic patients. After understanding TSC and tethered cord syndrome (TCS), more aggressive approaches became preferred. A PubMed search suggested that there was a dramatic increase of publications on the topic beginning around 1980. There have been immense academic achievements and technical evolutions since then. From the authors' viewpoint, landmark achievements in this field are listed as follows: (1) establishment of the concept of TSC and the understanding of TCS; (2) unraveling the process of secondary and junctional neurulation; (3) introduction of modern intraoperative neurophysiological mapping and monitoring (IONM) for surgery of spinal lipomas, especially the introduction of bulbocavernosus reflex (BCR) monitoring; (4) introduction of radical resection as a surgical technique; and (5) proposal of a new classification system of spinal lipomas based on embryonic stage. Understanding the embryonic background seems critical because different embryonic stages bring different clinical features and of course different spinal lipomas. Surgical indications and selection of surgical technique should be judged based on the background embryonic stage of the spinal lipoma. As time flows forward, technology continues to advance. Further accumulation of clinical experience and research will open the new horizon in the management of spinal lipomas and other SBO in the next half-century., (© 2023. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Determine whether craniocaudal spinal cord tumor location affects long-term neurologic outcomes in adults diagnosed with spinal ependymomas (SE). A retrospective cohort analysis of patients aged ≥ 18 years who underwent surgical resection for SE over a ten-year period was conducted. Tumor location was classified as cervical, thoracic, or lumbar/conus. Primary endpoints were post-operative McCormick Neurologic Scale (MNS) scores at < 3 days, 6 weeks, 1 year, and 2 years. One-way ANOVA was performed to detect significant differences in MNS scores between tumor locations. Twenty-eight patients were identified. The average age was 44.2 ± 15.4 years. Sixteen were male, and 13 were female. There were 10 cervical-predominant SEs, 13 thoracic-predominant SEs, and 5 lumbar/conus-predominant SEs. No significant differences were observed in pre-operative MNS scores between tumor locations (p = 0.73). One-way ANOVA testing demonstrated statistically significant differences in post-operative MNS scores between tumor locations at < 3 days (p = 0.03), 6 weeks (p = 0.009), and 1 year (p = 0.003); however, no significant difference was observed between post-operative MNS scores at 2 years (p = 0.13). The mean MNS score for patients with thoracic SEs were higher at all follow-up time points. Tumors arising in the thoracic SE are associated with worse post-operative neurologic outcomes in comparison to SEs arising in other spinal regions. This is likely multifactorial in etiology, owing to both anatomical differences including spinal cord volume as well as variations in tumor characteristics. No significant differences in 2-year MNS scores were observed, suggesting that patients ultimately recover from neurological insult sustained at the time of surgery., (© 2023. The Author(s).)

Background: Neuroimaging has evolved from anatomical imaging toward a multi-modality comprehensive anatomical and functional imaging in the past decades, important functional data like perfusion-weighted imaging, permeability imaging, diffusion-weighted imaging (DWI), and diffusion tensor imaging (DTI), tractography, metabolic imaging, connectomics, event-related functional imaging, resting state functional imaging, and much more is now being offered., Summary: Precision diagnostics has proven to be essential for precision treatment. Many minimal invasive techniques have been developed, taking advantage of digital subtraction angiography and interventional neuroradiology. Furthermore, intraoperative CT and/or MRI and more recently MR-guided focused ultrasound have complemented the diagnostic and therapeutic armamentarium., Key Messages: In the current manuscript, we discuss standard imaging sequences including advanced techniques like DWI, DTI, susceptibility-weighted imaging, and 1H magnetic resonance spectroscopy, various perfusion weighted imaging approaches including arterial spin labeling, dynamic contrast enhanced imaging, and dynamic susceptibility contrast imaging. Pre-, intra, and postoperative surgical imaging including visualize imaging will be discussed. The value of connectomics will be presented for its value in neuro-oncology. Minimal invasive therapeutic possibilities of interventional neuroradiology and image-guided laser ablation and MR-guided high-intensity-focused ultrasound will be presented for treatment of pediatric brain and spinal cord tumors. Finally, a comprehensive review of spinal cord tumors and matching neuropathology has been included., (© 2023 The Author(s). Published by S. Karger AG, Basel.)

Purpose: This study aimed to investigate the neurological outcome, trends and sequelae following surgical or conservative treatment of intramedullary spinal cord cavernous malformations (ISCCMs)., Methods: A systematic review was performed according to the Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) guidelines. The primary outcome measure was the change in the neurological status after surgery or conservative management. A logistic regression analysis investigating prognostic factors related to outcome was also performed., Results: Twenty-one studies with 1091 patients in total were included, of which 1005 (92.1%) underwent surgical resection and 86 (7.9%) were treated conservatively. Gross total resection was achieved in 95.7% of the patients and partial resection in 4.3%. Most lesions (60.2%) were located in the thoracic spine and presented with motor (60.4%) and sensory deficits (59.7%). In the long term, surgical treatment resulted in an improved neurological status in 36.9% of the patients, in 55.8% it remained stable, and in 7.3% it deteriorated compared to the preoperative state. In the conservative cohort, 21.7% improved, 69.6% remained stable, and 8.7% deteriorated. Solitary lesions, duration of preoperative symptoms less than 3 months as well as an improved post-operative neurological status were predictors of a favourable long-term outcome., Conclusions: Whenever feasible, symptomatic patients with ISCCM are recommended to undergo surgery within 3 months from symptom onset. Absence of multiple lesions and, most importantly, post-operative symptom improvement foresee a favourable long-term outcome. Further research is warranted to discern the role of conservative treatment in symptomatic patients., (© 2022. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Background: Spinal cord cavernous malformations (CMs) account for 5 to 12% of all spinal vascular malformations. Surgical removal is indicated in symptomatic patients, especially if the CM comes close to the dorsal or lateral surface of the spinal cord. Spinal cord CMs pose critical challenges for the potential of severe disabling complications., Method: We described the step-by-step surgical principles of spinal cord CM microsurgical resection. The main surgical steps are also illustrated in an accompanying operative video., Conclusion: Pre-surgical planning of the basic steps and good contingency management skills are paramount for an effective and safe spinal cord CM excision., (© 2022. The Author(s), under exclusive licence to Springer-Verlag GmbH Austria, part of Springer Nature.)

Sodium fluorescein (NaFL) has been used to aid in the resection of primary and secondary lesions within the brain. Comparatively, there is limited research on clinical applications for lesions within the spinal cord. Fluorescein-guided microsurgery may increase the ability to localize and safely surgically treat spinal lesions. Twelve patients with spinal cord lesions received fluorescein sodium 10% (Alcon Laboratories INC, Fort Worth, TX, USA) at 3 mg/kg prior to surgical resection. Intraoperative visualization of fluorescence was performed using a Zeiss Pentero (Carl Zeiss AG, Oberkochen, Germany) microscope equipped with a Yellow560 filter or a Leica OH6 (Leica Microsystems, Wetzlar, Germany) equipped with a FL560 filter. Administration of NaFL resulted in lesional fluorescent contrast extravasation and facilitated surgical resection and localization in all twelve patients. In patients with a goal of complete resection, NaFL aided in complete resection of the spinal lesions in seven patients. In surgical resection patients, pathology was consistent with WHO grade I myxopapillary ependymoma in one patient, WHO grade II ependymoma in five patients, and nerve sheath tumor in one patient. In the other five patients, NaFL allowed for intraoperative tissue identification and successful tissue biopsy. In patients undergoing biopsy, tissue samples were positive for an intramedullary abscess, EBV-driven lymphoproliferative disease, and primary glial neoplasms. Fluorescein is a helpful microsurgical tool in guiding surgical resection and in the localization of intramedullary spinal lesions. Further research is necessary to explore fluorescein sodium applications in the resection of spinal cord lesions., (© 2021. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Multiple factors, such as tumor size, lateralization, tumor location, accompanying syringomyelia, and regional spinal cord atrophy, may affect the resectability and clinical prognosis of intramedullary spinal cord ependymomas. However, whether long-segmental involvement of the spinal cord may impair functional outcomes remains unclear. This study was aimed to compare perioperative neurological functions and long-term surgical outcomes between multisegmental ependymomas and their monosegmental counterparts. A total of 62 patients with intramedullary spinal cord ependymoma (WHO grade II) were enrolled, and all of them underwent surgical resection. The patients were classified into the multisegmental group (n = 43) and the monosegmental group (n = 19). Perioperative and long-term (average follow-up period, 47.3 ± 21.4 months) neurological functions were evaluated using the modified McCormick (mMC) scale and the modified Japanese Orthopaedic Association (mJOA) scoring system. Preoperative neurological functions in the multisegmental group were significantly worse than those in the monosegmental group (P < 0.05). However, postoperative short-term neurological functions, as well as long-term functional outcomes, were similar between the two groups (P > 0.05). Logistic regression analysis showed that preoperative mMC and mJOA scores were significantly correlated with neurological improvement during the follow-up period (P < 0.05). Multisegmental involvement of the spinal cord is associated with worse neurological functions in patients with intramedullary spinal cord ependymoma, while the long-term prognosis is not affected. The preoperative neurological status of the patient is the only predictor of long-term functional improvement., (© 2021. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Meningiomas are the most common intradural extramedullary tumors, followed by nerve sheath tumors that can also grow extradurally. Metastases are the most frequent extradural tumors and most commonly affect the thoracic vertebrae. Spinal fractures with column dislocation and/or instability require surgical fixation. Spine surgery for an extramedullary tumor or fracture usually involves decompression of neural elements and instrumentation for stabilization. These procedures risk spinal cord and nerve root injury. The incidence of nerve root deficits after resection of nerve sheath tumors is particularly high since the tumor grows from the rootlets. Intraoperative neurophysiologic monitoring and mapping techniques have been introduced to prevent iatrogenic neurologic deficits. These include motor and sensory evoked potentials, electromyography, compound muscle action potentials, and the bulbocavernosus reflex. The combination of techniques chosen for a particular procedure depends on the surgical level and the character of the lesion., (Copyright © 2022 Elsevier B.V. All rights reserved.)

Intramedullary spinal cord tumor (ISCT) surgery is challenged by a significant risk of neurological injury. Indeed, while most ISCT patients arrive to surgery in good neurological condition due to early diagnosis, many experience some degree of postoperative sensorimotor deficit. Thus, intraoperative neuromonitoring (IONM) is invaluable for providing functional information that helps neurosurgeons tailor the surgical strategy to maximize resection while minimizing morbidity. Somatosensory evoked potential (SEP), muscle motor evoked potential (mMEP), and D-wave monitoring are routinely used to continuously assess the functional integrity of the long pathways within the spinal cord. More recently, mapping techniques have been introduced to identify the dorsal columns and the corticospinal tracts. Intraoperative SEP decline is not a sufficient reason to abandon surgery, since SEPs are very sensitive to anesthesia and surgical maneuvers. Yet, a severe proprioceptive deficit may adversely impact daily life, and the value of SEPs should be reconsidered. While mMEPs are good predictors of short-term motor outcome, the D-wave is the strongest predictor of long-term motor outcome, and its preservation during surgery is essential. Mapping techniques are promising but still need validation in large cohorts of patients to determine their impact on clinical outcome. The therapeutic rather than merely diagnostic value of IONM in spine surgery is still debated, but there is emerging evidence that IONM provides an essential adjunct in ISCT surgery., (Copyright © 2022 Elsevier B.V. All rights reserved.)

Objective: Microsurgical resection of spinal ependymomas is associated with a considerable risk of postoperative neurological deterioration. We aimed to develop a risk score for outcome prediction after surgery for spinal ependymoma., Materials and Methods: All patients who underwent microsurgical resection of spinal ependymoma between 1980 and 2015 were included. Different perioperative parameters were collected for the score construction. Poor outcome was defined as the modified McCormick Scale (MMCS) >2 at 6 months after surgery., Results: Of 131 patients (mean age: 45.6 ± 16.7 years; 63 females), 38 cases (29%) showed poor outcome. Based on the univariate analysis, preoperative MMCS, subtotal tumor resection, proximal tumor level on the spinal cord, tumor extension, intramedullary location, and WHO grading were included in the multivariate analysis. The final risk score consisted of the following independent predictors: preoperative MMCS > 1 (1 point), proximal tumor level at Th 10 and higher (1 point), and tumor extension ≥ 3 vertebrae (1 point). The constructed score (0-3 points; Score for OUtcome after Resection of Spinal Ependymoma [SOURSE]) showed high diagnostic accuracy (area under the curve [AUC] = 0.883), which was superior to preoperative MMCS (AUC = 0.798) and Karnofsky Performance Status (AUC = 0.794). Patients scoring 0, 1, 2, and 3 points showed poor outcome in 0%, 12.9%, 54.6%, and 76.2% of the cases respectively., Conclusion: The presented SOURSE score based on preoperative neurologic condition, tumor location, and tumor extension could accurately predict the postoperative outcome in patients undergoing microsurgery of spinal ependymoma. Our data should be validated in a prospective trial., (Copyright © 2021 Elsevier B.V. All rights reserved.)

Background: Spinal hemangioblastomas (SHs) are rare and benign tumors. Primary symptoms include pain, hypoesthesia, and neuropathic pain (NP). Clinical symptoms may be as a result of tumor mass effect, peritumoral effect, syrinx, or venous congestion. No studies have focused on NP in SHs. The objective of this study was to review the rate and causes of NP in patients with SHs., Methods: The present study comprises a retrospective analysis of 13 patients with spinal hemangioblastomas. For the retrospective analysis of the patients, we analyzed the absence or presence of NP in the pre- and postoperative periods and its relationship with the level, location, and size of the tumor, as well as the size and location of the syrinx., Results: Postoperative NP was detected in 6 out of 13 patients. All 6 patients' tumors were located at the dorsal aspect of the spinal cord. There was a predominance of rostral syrinx location in patients with NP. Tumor size and level and syrinx size and level were not found to affect the occurrence of NP., Conclusions: The present study shows that NP is observable in both pre- and postoperative periods. Proximity of the tumor to the dorsal root entry zone, and especially the presence of rostral syrinx, are the main factors affecting postoperative NP symptomatology. It is concluded that the combination of these factors and iatrogenic injury of anatomic pathways of NP within the spinal cord are responsible for postoperative NP., (Copyright © 2021 Elsevier Inc. All rights reserved.)

Myxopapillary ependymoma (MPE) is a rare glial tumour mainly located in the areas of the conus medullaris, cauda equina and filum terminale of the spinal cord. Ectopic MPE tends to behave more aggressively and distant metastases are often seen. Unfortunately, no standard treatment options are established as only small series of treated patients and a few reported cases are available in the literature. We report the case of a 25-year-old woman who was initially diagnosed with a metastatic MPE, with multiple bilateral lung metastases. She was treated with an investigational monoclonal antibody antiprogrammed cell death protein 1, called tislelizumab (BGB-A317), following surgical resection of the perisacral primary mass. The response was long-lasting and side effects nil. Immunotherapy is a treatment modality to be considered in patients with rare tumours., Competing Interests: Competing interests: None declared., (© BMJ Publishing Group Limited 2020. No commercial re-use. See rights and permissions. Published by BMJ.)

Radiation-induced spinal glioblastoma is an extremely rare disease with only four previously published reports in the literature. We report the fifth case, a 69-year-old woman who previously underwent treatment with brachytherapy for cervical cancer, and thereafter presented with neurologic deficits from a conus medullaris tumour. Biopsy and histopathology confirm glioblastoma, not otherwise specified. Treatment of spinal glioblastoma consists of surgery, either biopsy or excision and chemoradiation. However, results are still unsatisfactory and prognosis remains poor., Competing Interests: Competing interests: None declared., (© BMJ Publishing Group Limited 2020. No commercial re-use. See rights and permissions. Published by BMJ.)

Objective: Hemangioblastomas of the posterior cranial fossa and spinal cord in adults are excessively vascularized, well-differentiated, and scarce tumors with no metastatic potential. This paper discusses its surgical management and outcome, pointing out their morphological, radiological, and histopathological aspects. This report based on a personal series of six patients and on a literature review., Methods: A single-institution personal 6-case series of adult patients diagnosed and operated on by a senior neurosurgeon (KIA) due to posterior cranial fossa or spinal cord hemangioblastoma was analyzed. For easier understanding of hemangioblastoma, we have classified them into four different types., Results: The tumors, which were all surgically treated, were located in the posterior cranial fossa in five patients (4 cerebellar, 1 brain stem) and intramedullary in the thoracic spinal cord in one patient. All patients successfully recovered neurologically after a complete tumor resection, having no post-operative neurological deficit or other complications., Conclusion: Surgical management of cerebellar and spinal cord hemangioblastoma in adults is highly dependent on its morphological features, as well as on microsurgical technique applied. Since huge differences exist between the cystic/nodular tumor type (Type 1) and the solid type and its two additional variants (Types 2-4), morphology is the most important consideration when deciding surgical approach. Despite significant morphological differences among different subtypes of hemangioblastomas, their histology appears to be relatively similar. Nonetheless, a meticulous and refined surgical technique has to be utilized to achieve a successful outcome.

Objective: Conus medullaris teratomas are extremely rare, and the treatment experience has been limited. The purpose of the present study was to evaluate the clinical characteristics, radiological features, surgical outcomes, and prognosis of patients with conus medullaris teratoma., Methods: We retrospectively reviewed the data from 39 patients who had undergone surgical resection for conus medullaris teratomas from January 2008 to December 2018. All the operations were performed by 1 senior doctor. The clinical features, pre- and postoperative magnetic resonance imaging findings, pathological features, treatment strategies, and outcomes were analyzed. The neurological status was evaluated using the modified Japanese Orthopaedic Association scale score., Results: Of the 39 patients, the mean age was 30.9 years. Of the 39 patients, 20 were male and 19 were female. The symptom duration ranged from 0.3 to 252 months (mean, 61.6 months). Bladder and bowel dysfunction was the most common symptom (76.9%). Total resection was achieved in 25 patients (64.1%), subtotal resection in 11 (28.2%), and partial resection in 3 (7.7%). A mature teratoma was confirmed in all 39 patients. The neurological outcomes were improved 16 patients (45.7%), stable in 14 (40.0%), and aggravated in 5 (14.3%) at a mean follow-up of 62.7 months. Recurrence developed in 1 patient who had undergone subtotal resection. A second surgery with total resection was performed, and the patient's neurological symptoms were stable during follow-up., Conclusions: Total surgical resection is the optimal treatment strategy for patients with conus medullaris teratoma. Safe maximum tumor removal and residual tumor inactivation using electrocoagulation are recommended when total resection cannot be achieved. Surgery can provide a low recurrence rate and an acceptable low complication rate., (Copyright © 2020 Elsevier Inc. All rights reserved.)

Aims: In central nervous system (CNS) tumors, surgery combined with radiotherapy may cure many tumors. The basic technique in conventional radiotherapy is craniospinal radiotherapy; in this technique, spinal cord can be treated with electron or photon beams. This study was aimed to compare two radiotherapy techniques in craniospinal radiotherapy, (a) treatment of spine with a single photon beam and (b) with a combination of photon and electron beams., Materials and Methods: The two techniques were planned. In the first technique, both brain and spine were irradiated with 6 MV photon beams. In the second technique, brain was irradiated with 6 MV photon and spine with 18 MeV electron beams. To compensate the dose deficiency in lumbar area, an anterior field of 15 MV photon beam was also applied in the second technique. The dose to target volume and organ at risks (OARs) were measured by thermoluminescent dosimeter and compared with the corresponding values calculated by Isogray treatment planning system., Results: OARs including heart, mandible, thyroid, and lungs received lower dose from technique 2 compared with technique 1; kidneys were exceptions which received higher dose in the technique 2., Conclusions: The dose to thyroid, mandible, heart, and lungs were lower in technique 2, while kidneys received higher dose in technique 2. This was caused by using the anterior 15 MV photon beam. Based on these results, for children, instead of photon beam for treatment of spinal cord, it is wiser to use electron beam., Competing Interests: None

Objective: To study on the clinical efficacy of precise localization of O-arm and navigation system in spinal cord lesions., Methods: From Augst 2015 to September 2019, 22 patients with spinal cord lesions were arranged in the group.The intraoperative cross-sectional images were acquired by O-arm image system, which were transferred to the Stealth navigation system, and fused with pre-opreative MRI images. The image fusion was completed by the Medtronic Synergy Cranial software. The fused images were used to locate spinal cord lesions, assisted by the navigation system. The navigation errors were evaluated by measuring the maximum distance between the end of the lesion in MRI and its real position., Results: The image fusion were completed in all patients, and we successfully completed the image-guided surgeries of the spinal cord lesions. The time of image processing was between 7 min and 19 min, and the mean value was 15.1 ± 2.2 min. The navigation error was between 0.9 mm and 5.3 mm, the mean value was 1.6 ± 0.9 mm., Conclusion: The application of precise localization of O-arm and navigation system in spinal cord lesions is clinically reliable and feasible., (Copyright © 2020 Elsevier B.V. All rights reserved.)

Background: Spinal cord astrocytoma is a rare neoplasm, and patients usually recur within months after surgery. There is currently a lack of consensus regarding post-operative treatment. Clinical data on the activity of systemic treatment like chemoradiotherapy and anti-angiogenic agents also remained scant. Next-generation sequencing (NGS) -based genomic profiling thus may help identify potential treatment options for a subset of patients that harbor actionable genetic alterations., Case Presentation: We reported for the first time a refractory case of grade III spinal cord astrocytoma that underwent two surgeries but eventually progressed following post-operative chemoradiotherapy plus bevacizumab. Hybridization capture-based NGS using a 381-gene panel disclosed cyclin dependent kinase 4 (CDK4) amplification and after receiving a triplet regimen containg palbociclib for 15 months, the patient achieved complete response., Conclusions: This case demonstrated the importance of genetic profiling and the benefit of a multi-modality treatment strategy in cancer management.

Background: For small and lateral lesions, in order to avoid postoperative sequelae related to dorso-median myelotomy, we propose to describe the use of a ventrolateral approach for intramedullary lesions., Method: Performing this approach entails that the denticulate ligament is cut from its dural attachment and retracted. Rotation of the spinal cord must be achieved with great caution and under electrophysiological monitoring. After pia mater incision, hydrodissection is useful to gently dissect the cavernoma and promote a cleavage plane., Conclusion: In the case of lateral intramedullary lesions, using this approach maximized the absence of postoperative deficit.

A woman in her late sixties was referred to the orthopaedic clinic with progressive lower limb weakness and gait disturbance. She was known to have breast cancer with pre-existing infiltrative disease in the left brachial plexus. Magnetic resonance imaging of the spine revealed an intramedullary spinal cord metastasis in the lower cervical cord at C6-C7. She underwent surgical excision but died within six weeks of surgery. This rare case of an intramedullary spinal cord metastasis highlights the extremely poor prognosis in this condition as well as the possibility of perineural invasion into the spinal cord from the brachial plexus lesion. A detailed discussion of the literature on intramedullary spinal cord metastases is also presented.

Intramedullary spinal cord tumors (IMSCT) comprise a rare subset of CNS tumors that have distinct management strategies based on histopathology. These tumors often present challenges in regards to optimal timing for surgery, invasiveness, and recurrence. Advances in microsurgical techniques and technological adjuncts have improved extent of resection and outcomes with IMSCT. Furthermore, adjuvant therapies including targeted immunotherapies and image-guided radiation therapy have witnessed rapid development over the past decade, further improving survival for many of these patients. In this review, we provide an overview of types, epidemiology, imaging characteristics, surgical management strategies, and future areas of research for IMSCT., Competing Interests: Disclosure M.H. Bilsky receives royalties from Globus and DePuy/Synthes and is on the Speaker’s Bureau for Brainlab and Varian. The other authors have nothing to disclose., (Copyright © 2019 Elsevier Inc. All rights reserved.)

Background: Malignant Intramedullary Spinal Cord Tumor are a relatively uncommon entity affecting patients whose prognosis is quickly and relentlessly dismal. Since the '50s Spinal Cordectomy' has been advocated for the surgical management of these conditions, but to date, no standard operative protocol has been reported yet., Objective: Although apparently "easy", burdened by virtually no further risk for the neurological function in paraplegic or severely paraparetic patients, SCt conceals notable pitfalls and surgical problems that are to date not yet completely discussed. The objective of the present paper is therefore to report a detailed stepwise description of the surgical technique., Methods and Results: SCt addresses the problem of reaching a surgical radicality in patients whom neurological preoperative conditions have already irreversibly declined to a deep nonfunctional motor impairment and whose preoperative Brain MRI scan rules out intracranial seeding. The dural sac along with the radicular pouches must be considered as possible seeding and recurrence locations therefore such structure should be "en-bloc" removed. The cranial medullary end of the resection should be identified on the ground of the preoperative MRI and intraoperatively confirmed with fresh histological examinations ruling out the presence of tumor cells above the cordectomy. Due to the topographic and functional medullary arterial anatomy, no SCt should be performed above T3. The risk of postoperative sagittal imbalance is high and therefore a concurrent posterior vertebral stabilization is required., Conclusion: Spinal Cordectomy is a safe and feasible "last chance" treatment to prolong survival in paraplegic or severely paraparetic patients., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

Background: A 61-year-old man was admitted complaining of myelopathy and back pain for 3 months., Case Description: A 15-mm hemangioma with calcification was noted on magnetic resonance imaging and computed tomography. Intraoperatively, the mass was hard with ill-defined demarcation. The cranial portion of the mass was brown and dark gray on the dorsal cord. During surgery, motor evoked potentials transiently decreased, but they fully recovered at the end of surgery. After surgery, the patient's symptoms recovered without severe neurologic deficit., Conclusions: Hemangioma calcificans, a variant of cavernous hemangioma with full calcification and ossification, is an extremely rare disease in the spine and brain. Here we report a rare case of intramedullary cavernous hemangioma with calcification of the spinal cord., (Copyright © 2019 Elsevier Inc. All rights reserved.)

Competing Interests: None

Objective: There is a paucity of literature investigating the clinical course of patients with spinal intramedullary cavernous malformations (ISCMs). We present a large case series of ISCMs to describe clinical presentation, natural history and outcomes of both surgical and conservative management., Methods: We retrospectively reviewed the clinical course of patients diagnosed with ISCMs at our institution between 1995 and 2016. Haemorrhage was defined as clinical worsening in tandem with imaging changes visualised on follow-up MRI. Outcomes assessed included neurological status and annual haemorrhage rates., Results: A total of 107 patients met inclusion criteria. Follow-up data were available for 85 patients. While 21 (24.7%) patients underwent immediate surgical resection, 64 (75.3%) were initially managed conservatively. Among this latter group, 16 (25.0%) suffered a haemorrhage during follow-up and 11 (17.2%) required surgical resection due to interval bleeding or neurological worsening. The overall annual risk of haemorrhage was 5.5% per person year. The rate among patients who were symptomatic and asymptomatic on presentation was 9.5% and 0.8%, respectively. Median time to haemorrhage was 2.3 years (0.1-12.3). Univariate analysis identified higher ISCM size (p=0.024), history of prior haemorrhage (p=0.013) and presence of symptoms (p=0.003) as risk factors for subsequent haemorrhage. Multivariable proportional hazards analysis revealed presence of symptoms to be independently associated with haemorrhage during follow-up (HR 9.39, CI 1.86 to 170.8, p=0.013)., Conclusion: Large, symptomatic ISCMs appear to be at increased risk for subsequent haemorrhage. Surgery may be considered in such lesions to prevent rebleeding and subsequent neurological worsening., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2019. No commercial re-use. See rights and permissions. Published by BMJ.)

Objective: In this study, we retrospectively reviewed our experience in the surgical management of solitary fibrous tumor (SFT)/hemangiopericytomas (HPCs) of the spinal cord., Methods: Sixteen patients with SFT/HPCs of the spinal cord were enrolled in this study. Data on clinical presentation, radiologic findings, histopathologic features, surgical treatment, adjuvant therapy, and prognosis were retrospectively reviewed. Kaplan-Meier curves and log-rank tests were used to identify the prognostic factors for recurrence and overall survival (OS)., Results: Our series included 6 men and 10 women, with a male/female ratio of 1:1.7. Magnetic resonance imaging (MRI) showed slightly hyperintense lesions on T2-weighted images for all 16 patients. All tumors showed positive immunohistochemical staining for signal transducer and activator of transcription 6. Statistical analysis of clinical data showed that age, gender, tumor location, tumor size, medullary compartment location, and Ki-67 index were not associated with recurrence and OS (P > 0.05). However, World Health Organization grade III was significantly associated with recurrence (P < 0.01). Gross total resection (GTR) and postoperative radiotherapy significantly reduced recurrence (P < 0.01 and P < 0.05), but only GTR showed remarkable benefits to improve OS (P < 0.05)., Conclusions: SFT/HPCs of spinal cord are rare neoplasms with a propensity to recur. Hyperintensity on T2-weighted magnetic resonance imaging combined with positive immunohistochemical staining for signal transducer and activator of transcription 6 are important clues for classification and differentiation of these tumors. The extent of resection, World Health Organization grade, and postoperative radiotherapy might be predictive factors for recurrence. Complete tumor resection should be sought whenever possible, and adjuvant radiotherapy is recommended after surgical resection. Moreover, regular and long-term follow-up is mandatory to monitor recurrence., (Copyright © 2018 Elsevier Inc. All rights reserved.)

Purpose: To report a case series of surgically proven spinal ependymomas of WHO grade II in which there were changes in the preoperative MRI characteristics over time., Methods: A total of 71 patients with spinal cord ependymoma of WHO grade II underwent surgery. There were ten cases in which surgery was performed at an average of 2.2 years after the tumor was found. Cystic components, syringomyelia, hemorrhage "cap sign," Gd enhancement pattern, characteristic changes in MRI, MIB-1 index, and neurological assessment during the preoperative period were examined., Results: Cases with a huge cyst showed further enlargement of the cyst on the caudal and rostral sides with hemosiderin formation over time and changes in the pattern of Gd enhancement. In contrast, cases without initial cyst did not show cyst formation, and nodular homogeneous lesion remained without changes in Gd enhancement. Regarding neurological status, two cases with cyst enlargement and hemosiderin formation had worsened non-independent gait preoperatively., Conclusions: MRI in cases of spinal ependymomas of WHO grade II showed characteristics such as hemorrhage and cyst formation that varied over time. In particular, cases with cyst and hemosiderin showed tumor enlargement, including enlargement of lesions on the caudal and rostral sides and enlargement of Gd-enhanced lesions. These characteristics might influence gait ability during preoperative period. We emphasize that early surgery is still the standard of care for cervical intramedullary ependymoma, and our findings in this study should not be interpreted to indicate that such early surgery is not necessary in symptomatic cases. These slides can be retrieved under electronic supplementary material.

Aim: To demonstrate the value of special intraoperative neuromonitoring techniques for cauda equina and conus medullaris tumors (CECMT) by describing standard methods used at our center., Material and Methods: Neurophysiological records were retrospectively reviewed for 16 patients (eight females and eight males; age range: 27â€"60 years) who underwent surgery for CECMT at our department between 2016 and 2018., Results: Motor and/or sensorial deficits were preoperatively identified in 10 patients; no patients had bladder or sexual dysfunction. Motor evoked potential (MEP) loss occurred in seven patients with full or partial recovery. No changes were seen in pudendal somatosensory evoked potential (SEP) or bulbocavernosus reflex (BCR), and morphological deterioration and amplitude loss of tibial SEPs were present in four patients. Postoperatively, no new neurological deficits and/or bladder and sexual dysfunction were present., Conclusion: Pudendal SEP and BCR are useful tests for monitoring CECMT surgeries. BCR is an easily obtainable modality for preserving sacral functions and recommended as a primary monitoring modality in conjunction with traditional neurophysiological techniques during CECMT surgery.

Purpose: Diffusion tensor imaging (DTI) allows studying the micro and macro architecture. One of the major challenges in dysraphism is to know the morphologic organization of the spinal cord. In a preliminary work, spinal lipoma was chosen for analyzing the micro-architecture parameters and fiber morphology of the spinal cord by DTI with tractography., Methods: Twelve patients (0-8 years) related to spinal lipomas treated between May 2017 and March 2018 were included. Tractography reconstruction of the conus medullaris of 12 patients were obtained using the MedINRIA software. The diffusion parameters have been calculated by Osirix DTImap plugin., Results: We found a significant difference in the FA (p = 0.024) between two age groups (< 24 months old and > 24 months old). However, no significant differences in the mean values of FA, RD, and MD between the level of the lipoma and the level above were noted. The tractography obtained in each case was coherent with morphologic sequences and reproducible. The conus medullaris was deformed and shifted. Destruction or disorganization of fibers and any passing inside the lipomas was not observed., Conclusions: Tractography of the conus medullaris in a very young pediatric population (0-8 years old) with a spinal lipoma is possible, reproductive, and allows visualization of the spinal cord within the dysraphism. Analysis of the FA shows that the presence of a lipoma seems to have an effect on the myelination of the conus medullaris. It is during the probable myelination phase that the majority of symptoms appear. Is the myelination per se the cause?

Background and Importance: Advances in minimally invasive (MIS) and mini-open surgical approaches have led to reductions in perioperative morbidity without compromising rates of resection of non-degenerative intradural spinal pathologies. Whether these approaches may be adapted for the surgical resection for intramedullary vascular malformations - such as cavernous malformations (CMs) - has yet to be reported. The authors describe a mini-open transspinous approach to resect a ruptured intramedullary CM of the conus medullaris., Clinical Presentation: A 28-year-old man presented with sudden onset of bilateral lower extremity weakness, urinary retention and saddle anesthesia. Magnetic resonance imaging demonstrated a ruptured CM within the conus medullaris with pronounced extralesional hemorrhage. A mini-open transspinous approach with an expandable tubular retractor was successfully applied to facilitate microsurgical resection of the CM and evacuation of the associated hematoma. The patient made a good neurologic recovery, and postoperative imaging confirmed a gross total resection of the CM., Conclusion: A mini-open transspinous approach utilizing an expandable tubular retractor offers feasible less invasive alternative to provide dorsal midline access for the microsurgical resection of intramedullary spinal CMs. Larger case series or future randomized prospective trials are warranted to fully explore suitability of MIS techniques for the surgical management of intradural spinal cord vascular pathologies - such as CMs., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

Spinal cord biopsy is a difficult procedure fraught with the risk of false-negative results or even misdiagnosis in up to 30% of cases. Differential diagnoses of spinal cord lesions include a wide range of inflammatory, infectious and neoplastic diseases. Given the importance of correctly managing these pathologies, it is crucial to avoid delays in making the correct diagnosis in order to improve the patient's outcome. We present here the case of a 21-year-old male with rapidly progressing sphincter and lower limb motor dysfunctions up to complete paraplegia with evidence of thoracic spinal cord lesion on magnetic resonance imaging. None of the blood and cerebrospinal fluid tests pointed to a diagnosis, while a first spinal cord biopsy revealed an inflammatory necrotic process. After several weeks of empirical treatments and clinical stability, the patient started having focal structural seizures that became generalized with local progression of the lesion and diffuse leptomeningeal spread on magnetic resonance imaging. A second spinal cord biopsy found a grade IV glioblastoma with H3 K27M histone mutation. Unfortunately the patient passed away before any treatment could be initiated. In this report, the authors analyze the difficulty of making the rapid, correct diagnosis of a highly malignant intrinsic spinal cord lesion, discussing also possible strategies to avoid diagnostic delays and to improve the outcome of these difficult patients., (Copyright © 2018 Elsevier Masson SAS. All rights reserved.)

The surgical management of anteriorly located spinal cord hemangioblastomas remains a challenge. Different approaches have been published, of which the anterior approach seems to be the most obvious and commonly used. A posterior approach might be more suitable in certain patients, especially in cases of cystic hemangioblastomas. The authors present 3 cases of anterior spinal hemangioblastomas, which were all resected via a posterior approach. The authors discuss the rationale for choosing this approach and explain the technique in detail.

Background: Standard fluoroscopic guidance (C-arm fluoroscopy) has been routinely used for intraoperative localization of spinal level for surgical removal of intraspinal tumour, while it is not suitable for selected patients, e.g. pregnant women, who need to avoid radiation exposure. Fusion imaging of real-time ultrasound (US) and magnetic resonance imaging (MRI) is a radiation-free technique which has been reported to have good localization accuracy in managing several conditions., Clinical Presentation: A 37-year-old pregnant patient, presented with a progressively aggravating lower back pain for 20 days and was incapable of lying supine with lower extremities swelling for 1 week, was referred to our hospital in her 18th week of gestation. Lumbar MRI identified an L1 level intraspinal lesion, and surgery was planned. To avoid the ionizing radiation generated by fluoroscopy, volume navigation technique (VNT) based fusion imaging of US and MRI was used to localize the intraspinal lesion, which was removed entirely via minimally invasive interlaminar approach. Pathological examination confirmed the diagnosis of ependymoma of the conus medullaris. Her symptoms were largely relieved after the operation, and a healthy baby was delivered at the 40th week of pregnancy., Conclusion: We presented the first case of using VNT based fusion imaging of real-time US/MRI to guide the surgical resection of an intraspinal tumour. Future study with larger patient number is needed to validate this technique as an alternative to fluoroscopy in patients who need to avoid radiation exposure.

Ependymomas of the spinal cord remain confined to the CNS and vary in presentation, depending on WHO grade. Higher-grade lesions usually cannot be surgically removed due to their infiltrative growth pattern. Spinal cordectomy has been proposed as a rescue treatment to improve survival in patients with high-grade as well as recurrent lesions. This report details an instructive and unique case of long-term follow-up of a patient who underwent cordectomy from T-4 through S-5 for what was initially diagnosed as a high-grade glial neoplasm of the spinal cord in 1993. The patient lived symptom free for 13 years after spinal cord resection and then presented with numerous bilateral extraspinal (intraabdominal and intrathoracic) tumors, which eventually led to her death 15 years after the cordectomy. In this case, spinal cordectomy was effective in preventing the ascending spread of the neoplasm, but ultimately not effective in preventing recurrence in the plicated distal dural sac.

Non-Hodgkin lymphomas are a heterogeneous group of tumours, with diffuse large B-cell lymphomas (DLBCL) being particularly common. Cases of DLBCLs developing in the central nervous system, especially in the spinal cord, are extremely rare and thus pose significant diagnostic and therapeutic problems, particularly for orthopaedists and neurologists since these are the specialists the patients first consult. The tumours often appear in immunosuppressed patients and standard chemotherapy is ineffective. This paper presents the case of a 44-year-old male with a lymphoma located in the spinal cord at the C7-Th1 level. The symptoms appeared suddenly and progressed rapidly, with dissociated sensory loss and limb paresis being the most pronounced. Imaging studies and the rapid symptom progression suggested neoplastic disease. An emergency surgical procedure was performed in order to decompress the spinal cord and thus limit neurological deficits. Tumour resection allowed for making a diagnosis. By four weeks after the surgery, the tumour had grown larger than before the procedure. Chemotherapy with MTX and Ara-C and intrathecal MTX resulted in full remission. Consolidation was achieved with radiotherapy. Currently, with the low incidence of such tumours, there are no standards of management in patients with DLBCLs of the CNS. The literature contains only a few case reports on successfully treated spinal cord DLBCLs.

Objective: The goal of this study was to compare the clinical outcomes of posterior surgery with combined laminectomy and thoracoscopic surgery for treating dumbbell-type thoracic cord tumors., Patients and Methods: We retrospectively analyzed 32 cases of dumbbell-type thoracic cord tumors treated by two surgical procedures in our center from February 2003 to July 2013. CASES WERE DIVIDED INTO TWO GROUPS DEPENDING ON THE TYPE OF SURGERY: Group A cases (n = 12) underwent posterior surgery followed by laminectomy, costotransversectomy and instrumentation; Group B cases (n = 20) underwent posterior laminectomy and anterior video-assisted thoracoscopic surgery in a single-stage procedure. Operation time, blood loss, hospitalization, recovery of neurological function, and complications were compared between the two groups., Results: Complete surgical excision was achieved in both groups. All patients were followed up for an average of 7.4 ± 2.8 years (range, 3-13). At the final follow-up visit, there was no tumor recurrence and no differences in neurological results between the two groups (P > 0.05). However, the average operative duration, blood loss, hospitalization, and rate of complications were significantly lower in Group A compared to Group B (P < 0.05)., Conclusion: Both posterior surgery and the posterior surgery combined with anterior thoracoscopic surgery were effective for removing dumbbell-type thoracic cord tumors. However, posterior surgery alone was associated with reduced operative duration and rate of complications compared to the combined surgical approach., (Copyright © 2018 Elsevier B.V. All rights reserved.)

Background: Motor evoked potential (MEP) recording is used as a method to monitor integrity of the motor system during surgery for intramedullary tumors (IMTs). Reliable sensitivity of the monitoring in predicting functional deterioration has been reported. However, we observed false positives and false negatives in our experience of 250 surgeries of IMTs., Objective: To delineate specificity and sensitivity of MEP monitoring and to elucidate its limitations and usefulness., Methods: From 2008 to 2011, 58 patients underwent 62 surgeries for IMTs. MEP monitoring was performed in 59 operations using transcranial electrical stimulation. Correlation with changes in muscle strength and locomotion was analyzed. A group undergoing clipping for unruptured aneurysms was compared for elicitation of MEP., Results: Of 212 muscles monitored in the 59 operations, MEP was recorded in 150 (71%). Positive MEP warnings, defined as amplitude decrease below 20% of the initial level, occurred in 37 muscles, but 22 of these (59%) did not have postoperative weakness (false positive). Positive predictive value was limited to 0.41. Of 113 muscles with no MEP warnings, 8 muscles developed postoperative weakness (false negative, 7%). Negative predictive value was 0.93. MEP responses were not elicited in 58 muscles (27%). By contrast, during clipping for unruptured aneurysms, MEP was recorded in 216 of 222 muscles (96%)., Conclusion: MEP monitoring has a limitation in predicting postoperative weakness in surgery for IMTs. False-positive and false-negative indices were abundant, with sensitivity and specificity of 0.65 and 0.83 in predicting postoperative weakness.

Objective: Unilateral hemilaminectomy, which is used to remove spinal cord tumors, is simpler than laminoplastic laminotomy and affords certain biomechanical advantages. However, both incomplete tumor removal and inadvertent infliction of spinal cord damage attributable to the narrow surgical corridor remain of concern. When a spinal cord tumor is to be removed, it is important to ensure that the dural window along the surgical corridor is of adequate width. This study aimed to determine that the utility of lateral base dural tacking (LBT) method when cord tumor surgery is performed using a unilateral hemilaminectomy-a comparison of dural window widths with a traditional dural tack-up and a suspending-out (DSO) method with the aid of digital image-analysis software., Methods: Twenty-one consecutive patients who had intradural-extramedullary spinal cord tumors removed using a unilateral hemilaminectomy were included in the study and analyzed retrospectively. We acquired DSO and LBT dural window images using surgical microscopes under identical conditions in consecutive order and then removed the tumors using the LBT method. We used digital image-analysis software to analyze the images quantitatively. The pixel numbers of LBT and DSO window were compared using a paired t test., Results: Twenty-one tumorous lesions were successfully removed without any major problems using a unilateral hemilaminectomy through LBT windows. The mean pixel numbers of the LBT and DSO windows were 126,787 ± 41,938 and 85,940 ± 21,638. The LBT windows were 46% larger than the DSO windows (P < 0.001)., Conclusions: We objectively proved that the utility of the LBT method for widening the surgical corridor created during hemilaminectomy., (Copyright © 2017 Elsevier Inc. All rights reserved.)