Largest neurosurgical social media group and its impact on communication and research.

BACKGROUND: The use of social media to communicate and disseminate knowledge has increased exponentially, especially in the field of neurosurgery. 'Neurosurgery cocktail' (NC) was developed by a group of young neurosurgeons as a means of sharing didactic materials and clinical experiences via social media. It connects 35.000 neurosurgeons worldwide on multiple platforms, primarily Facebook and Twitter. Given the rising utilization of social media in neurosurgery, the popularity of NC has also increased since its inception. In this study, the authors surveyed the social media analytics of NC for both Facebook and Twitter. Besides, we reviewed the literature on the use of social media in neurosurgery. METHODS: Facebook and Twitter metrics were extracted through each respective platform's analytics tools from December 2020 (earliest available date for data analysis) through January 2021. A literature search was conducted using PubMed (MEDLINE) and Scopus databases. RESULTS: On Facebook, as of January 2021, the group had a total of 25.590 members (87.6% male), most commonly (29%) between 35 and 44 years of age with over 100 countries were represented. As of January 2021, they had amassed 6457 followers on Twitter. During the last 28 d between December 2020 and January 2021, the account published 65 tweets that garnered a total of 196,900 impressions. Twelve articles were identified in our literature review on the use of social media within the neurosurgical community. CONCLUSIONS: NC is one of the most widely utilized neurosurgical social media resources available. Sharing knowledge has been broadened thanks to the recent social media evolution, and NC has become a leading player in disseminating neurosurgical knowledge.

Endovascular and Antithrombotic Treatment in Blunt Cerebrovascular Injuries: A Systematic Review and Meta-Analysis.

OBJECTIVES: Ischemic stroke has been estimated to occur in up to 26% of patients with blunt cerebrovascular injury (BCVI). Antithrombotic therapy (AT) may be used for stroke prevention, but the role of endovascular treatment (ET) remains unclear. We systematically reviewed the literature on AT and ET for the treatment of patients with BCVIs. MATERIALS AND METHODS: PubMed, EMBASE, Web of Science, and Cochrane were searched upon the PRISMA guidelines to include studies reporting the use of ET in BCVI patients. Post-ET neurologic outcomes, radiographic responses, and complication rates were assessed. A fixed-effect model meta-analysis was performed to compare treatment-related post-BCVI ischemic stroke rates between AT and ET protocols. RESULTS: We included 16 studies comprising 352 patients undergoing ET for BCVI. Mean post-ET rates of good neurologic outcomes and radiologic responses were 86.9% (range, 63.6-100%) and 94.0% (range 57.1-100%), respectively. Mean post-ET complication rate was 5.2% (range, 0-66.7%). Seven studies compared the roles of AT (delivered in 805 patients) and ET (performed in 235 patients) for preventing the onset of post-BCVI ischemic strokes. No significant difference in rates of post-BCVI ischemic stroke was found between patients receiving AT vs patients undergoing ET (OR 0.71, 95% CI: 0.35-1.42, p = 0.402). CONCLUSION: AT and ET may be comparable in preventing the occurrence of ischemic stroke following BCVIs. AT may be preferred as the less-invasive first-line therapy, but ET showed favorable rates of post-treatment clinical and radiologic outcomes, coupled with low rates of treatment-related complications.

iPSCs: A Preclinical Drug Research Tool for Neurological Disorders.

The development and commercialization of new drugs is an articulated, lengthy, and very expensive process that proceeds through several steps, starting from target identification, screening new leading compounds for testing in preclinical studies, and subsequently in clinical trials to reach the final approval for therapeutic use. Preclinical studies are usually performed using both cell cultures and animal models, although they do not completely resume the complexity of human diseases, in particular neurodegenerative conditions. To this regard, stem cells represent a powerful tool in all steps of drug discovery. The recent advancement in induced Pluripotent Stem Cells (iPSCs) technology has opened the possibility to obtain patient-specific disease models for drug screening and development. Here, we report the use of iPSCs as a disease model for drug development in the contest of neurological disorders, including Alzheimer's (AD) and Parkinson's disease (PD), Amyotrophic lateral Sclerosis (ALS), and Fragile X syndrome (FRAX).

Restoration of Thoracolumbar Spine Stability and Alignment in Elderly Patients Using Minimally Invasive Spine Surgery (MISS). A Safe and Feasible Option in Degenerative and Traumatic Spine Diseases.

Minimally invasive spine surgery (MISS), including percutaneous pedicle-screw fixation (PPSF), mini-open transforaminal lumbar interbody fusion (m-open TLIF), vertebroplasty, and stentoplasty, allows the preservation of neurological function and the restoration of spine stability, while reducing associated risks and complications. This study aimed to analyze the safety and efficacy of MISS in elderly patients suffering from degenerative or traumatic thoracolumbar diseases. Forty-five patients (28 females), with a mean age of 73 years (range 65-89), suffering from osteoporotic vertebral fractures (24), degenerative spondylolisthesis (15), and lumbar canal stenosis with instability and/or de novo scoliosis (6) were included.Twenty-one patients underwent PPSF and m-open TLIF. The remaining patients received PPSF without interbody fusion, and in six of these fenestrated screws were used for vertebral body cement augmentation.Functional evaluation was obtained with a visual analog scale (VAS) and the Oswestry Disability Index (ODI) pre- and postoperatively. Preoperative imaging included X-rays, computed tomography (CT), and magnetic resonance imaging (MRI). Patients were followed-up with X-rays, and a CT scan was also obtained at the last follow-up. Follow-up ranged from 6 to 59 months (mean 28 months). Follow-up CT scan documented intersomatic fusion in only 14 % of patients treated with m-open TLIF. Despite the high incidence of non-union, mean VAS and ODI scores showed a significant improvement, with a reduction of mean VAS from 9 to 4 and a reduction of mean ODI from 76.33 to 38.15 %. Only three patients developed postoperative complications. No patients showed neurological deficits.Minimally invasive spine surgery for degenerative and traumatic spinal diseases is a safe and effective treatment also in elderly patients.

Direct and Oblique Approaches to the Craniovertebral Junction: Nuances of Microsurgical and Endoscope-Assisted Techniques Along with a Review of the Literature.

PURPOSE: The aim of this review is to provide an update of the technical nuances of microsurgical and endoscopic-assisted approaches to the craniovertebral junction (transnasal, transoral, and transcervical), and to report on the available clinical results in order to identify the best strategy. METHODS: A nonsystematic update of the reviews and reporting on the anatomical and clinical results of endoscopic-assisted and microsurgical approaches to the craniovertebral junction (CVJ) was performed. RESULTS: Pure endonasal and cervical endoscopic approaches still have some disadvantages, including their steep learning curves and their deeper surgical fields. Endoscopically assisted transoral surgery with 30° endoscopes represents an emerging option compared with standard microsurgical techniques for transoral approaches to the anterior CVJ. This approach should be considered as complementary to, rather than as an alternative to the traditional transoral-transpharyngeal approach. CONCLUSIONS: The transoral (microsurgical or video-assisted) approach with sparing of the soft palate still remains the gold standard compared with the "pure" transnasal and transcervical approaches, due to the wider working channel provided by the former technique. The transnasal endoscopic approach alone appears to be superior when the CVJ lesion exceeds the upper limit of the inferior third of the clivus. Of particular interest is the evidence that advances in reduction techniques can avoid the ventral approach.

Lumbar Spinous Process-Splitting Technique for Ligamentum Flavum Cyst Removal.

BACKGROUND: Laminotomy for lumbar stenosis is a well-defined procedure and represents a routine in every neurosurgical department. It is a common experience that the uni- or bilateral paraspinal muscle detachment, together with injury of the supra- and interspinous ligaments, can lead to postoperative pain. In the literature, the application of a minimally invasive technique, the lumbar spinous process-splitting (LSPS) technique, has been reported. METHODS: In this study, we present a case series of 12 patients who underwent LSPS from September 2019 to April 2020. Two patients had a cyst of the ligamentum flavum, eight a single-level lumbar canal stenosis (LCS), and two a two-level LCS. Moreover, we propose a novel morphological classification of postoperative muscle atrophy and present volumetric analysis of the decompression achieved. RESULTS: There were no complications related to this technique. In all patients, the vertebral canal area was more than doubled by the procedure. The muscle sparing showed grade A, according to our classification. CONCLUSION: To our knowledge, this is the first description of this surgical technique and the first LSPSL case series in Europe. Furthermore, cases of ligamentum flavum cyst removal using this safe and effective technique have not yet been reported.

Primary Intracranial Gliosarcoma: Is It Really a Variant of Glioblastoma? An Update of the Clinical, Radiological, and Biomolecular Characteristics.

Gliosarcomas (GS) are sporadic malignant tumors classified as a Glioblastoma (GBM) variant with IDH-wild type phenotype. It appears as a well-circumscribed lesion with a biphasic, glial, and metaplastic mesenchymal component. The current knowledge about GS comes from the limited literature. Furthermore, recent studies describe peculiar characteristics of GS, such as hypothesizing that it could be a clinical-pathological entity different from GBM. Here, we review radiological, biomolecular, and clinical data to describe the peculiar characteristics of PGS, treatment options, and outcomes in light of the most recent literature. A comprehensive literature review of PubMed and Web of Science databases was conducted for articles written in English focused on gliosarcoma until 2023. We include relevant data from a few case series and only a single meta-analysis. Recent evidence describes peculiar characteristics of PGS, suggesting that it might be a specific clinical-pathological entity different from GBM. This review facilitates our understanding of this rare malignant brain tumor. However, in the future we recommend multi-center studies and large-scale metanalyses to clarify the biomolecular pathways of PGS to develop new specific therapeutic protocols, different from conventional GBM therapy in light of the new therapeutic opportunities.

Could nanoparticle systems have a role in the treatment of cerebral gliomas?

Malignant brain tumors are difficult to manage clinically and are associated with high rates of morbidity and mortality. Late diagnosis and the limitations of conventional therapies that may result from inefficient delivery of the therapeutic or contrast agent to brain tumors due to the blood-brain barrier and nonspecificity of the agents, are major reasons for this unsolved clinical problem. Nanotechnology involves the design, synthesis, and characterization of materials and devices that have a functional organization in at least one dimension on the nanometer scale. The nanoparticle has emerged as a potential vector for brain delivery, able to overcome the difficulties of modern strategies. Moreover, multifunctionality can be engineered into a single nanoplatform so that it can provide tumor-specific detection, treatment, and follow-up monitoring. This review reports the latest research in nanoparticle-based glioma treatment. FROM THE CLINICAL EDITOR: In recent years, nanoparticles have emerged as potential delivery vectors targeting brain tumors, including multifunctional NP-s allowing tumor-specific detection, treatment, and follow-up monitoring. This review summarizes the latest research in nanoparticle-based glioma treatment.

Corrigendum: Perforating Arteries of the Lemniscal Trigone: A Microsurgical Neuroanatomic Description.

[This corrects the article DOI: 10.3389/fnana.2021.675313.].

Perforating Arteries of the Lemniscal Trigone: A Microsurgical Neuroanatomic Description.

Background: The perforating arteries in the dorsolateral zone of the midbrain play a crucial role in the functions of the brain stem. Their damage due to herniation, pathological lesions, or surgery, favored by the narrow tentorial incisura, can lead to hemorrhages or ischemia and subsequently to severe consequences for the patient. Objective: In literature, not much attention has been directed to the perforating arteries in the lemniscus; in fact, no reports on the perforators of this anatomical region are available. The present study aims to a detailed analysis of the microanatomy and the clinical implications of these perforators, in relation to the parent vessels. We focused on the small vessels that penetrate the midbrain's dorsolateral surface, known as lemniscal trigone, to understand better their microanatomy and their functional importance in the clinical practice during the microsurgical approach to this area. Methods: Eighty-seven alcohol-fixed cadaveric hemispheres (44 brains) without any pathological lesions provided the material for studying the perforating vessels and their origin around the dorsolateral midbrain using an operating microscope (OPMI 1 FC, Zeiss). Measurements of the perforators' distances, in relation to the parent vessels, were taken using a digital caliper. Results: An origin from the SCA could be found in 70.11% (61) and from the PCA in 27.58% (24) of the hemispheres. In one hemisphere, an origin from the posterior choroidal artery was found (4.54%). No perforating branches were discovered in 8.04% of specimens (7). Conclusion: The perforating arteries of the lemniscal trigone stem not only from the superior cerebellar artery (SCA), as described in the few studies available in literature, but also from the posterior cerebral artery (PCA). Therefore, special attention should be paid during surgery to spare those vessels and associated perforators. A comprehensive understanding of the lemniscal trigone's perforating arteries is vital to avoid infarction of the brainstem when treating midbrain tumors or vascular malformations.

Multimodal Simulation of a Novel Device for a Safe and Effective External Ventricular Drain Placement.

BACKGROUND: External ventricular drain (EVD) placement is mandatory for several pathologies. The misplacement rate of the EVD varies widely in literature, ranging from 12.3 to 60%. The purpose of this simulation study is to provide preliminary data about the possibility of increasing the safety of one of the most common life-saving procedures in neurosurgery by testing a new device for EVD placement. METHODS: We used a novel guide for positioning the ventricular catheter (patent RM2014A000376). The trajectory was assessed using 25 anonymized head CT scans. The data sets were used to conduct three-dimensional computer-based and combined navigation and augmented reality-based simulations using plaster models. The data set inclusion criteria were volumetric head CT scan, without midline shift, of patients older than 18. Evans' index was used to quantify the ventricle's size. We excluded patients with slit ventricles, midline shift, skull fractures, or complex skull malformations. The proximal end of the device was tested on the cadaver. RESULTS: The cadaveric tests proved that a surgeon could use the device without any external help. The multimodal simulation showed Kakarla grade 1 in all cases but one (grade 2) on both sides, after right and left EVD placement. The mean Evans' index was 0.28. The geometric principles that explain the device's efficacy can be summarized by studying the properties of circumference and chord. The contact occurs, for each section considered, at the extreme points of the chord. Its axis, perpendicular to the plane tangent to the spherical surface at the entry point, corresponds to the direction of entry of the catheter guided by the instrument. CONCLUSION: According to our multimodal simulation on cadavers, 3D computer-based simulation, 3D plaster modeling, 3D neuronavigation, and augmented reality, the device promises to offer safer and effective EVD placement. Further validation in future clinical studies is recommended.

Primary Extracranial Meningiomas of the Head and Neck.

Meningiomas represent the most common benign histological tumor of the central nervous system. Usually, meningiomas are intracranial, showing a typical dural tail sign on brain MRI with Gadolinium, but occasionally they can infiltrate the skull or be sited extracranially. We present a systematic review of the literature on extracranial meningiomas of the head and neck, along with an emblematic case of primary extracranial meningioma (PEM), which provides further insights into PEM management. A literature search according to the PRISMA statement was conducted from 1979 to June 2021 using PubMed, Web of Science, Google Scholar, and Scopus databases, searching for relevant Mesh terms (primary extracranial meningioma) AND (head OR neck). Data for all patients were recorded when available, including age, sex, localization, histological grading, treatment, possible recurrence, and outcome. A total of 83 published studies were identified through PubMed, Google Scholar, and Scopus databases, together with additional references list searches from 1979 to date. A total of 49 papers were excluded, and 34 manuscripts were considered for this systematic review, including 213 patients. We also reported a case of a 45-year-old male with an extracranial neck psammomatous meningioma with sizes of 4 cm × 3 cm × 2 cm. Furthermore, whole-body 68Ga-DOTATOC PET/CT was performed, excluding tumor spread to other areas. Surgical resection of the tumor was accomplished, as well as skin flap reconstruction, obtaining radical removal and satisfying wound healing. PEMs could suggest an infiltrative and aggressive behavior, which has never found a histopathological correlation with a malignancy (low Ki-67, <5%). Whole-body 68Ga-DOTATOC PET/CT should be considered in the patient's global assessment. Surgical removal is a resolutive treatment, and the examination of frozen sections can confirm the benignity of the lesion, reducing the extension of the removal of healthy tissue surrounding the tumor.

The Superficial Anastomosing Veins of the Human Brain Cortex: A Microneurosurgical Anatomical Study.

Introduction: In this microneurosurgical and anatomical study, we characterized the superficial anastomosing veins of the human brain cortex in human specimens. Material and Methods: We used 21 brain preparations fixed in formalin (5%) that showed no pathological changes and came from the autopsy sections. The superficial veins were dissected out of the arachnoid with the aid of a surgical microscope. Results: We dissected nine female and 12 male brain specimens, with an average age of 71 ± 11 years (range 51-88 years). We classified the superficial veins in five types: (I) the vein of Trolard as the dominat vein; (II) the vein of Labbé as the dominant vein; (III) a dominant sylvian vein group, and the veins of Trolard and Labbé nonexistent or only rudimentary present without contact to the Sylvian vein group; (IV) very weak sylvian veins with the veins of Trolard and Labbé codominant; and V) direct connection of Trolard and Labbé bypassing the Sylvian vein group. The vein of Trolard was dominant (Type I) in 21.4% and the vein of Labbé (Type II) in 16.7%. A dominant sylvian vein group (Type III) was found in 42.9%. Type IV and Type V were found in 14.3 and 4.7% respectively. Conclusion: No systematic description or numerical distribution of the superior anastomotic vein (V. Trolard) and inferior anastomotic vein (V. Labbé) has been found in the existing literature. This study aimed to fill this gap in current literature and provide data to neurosurgeons for the practical planning of surgical approaches.

Posttraumatic Triple Acute Epidural Hematomas: First Report of Bilateral Synchronous Epidural Hematoma and a Third Delayed.

BACKGROUND: Development of a delayed acute epidural hematoma (DEDH) represents a rare event, characterized by a high mortality rate. It is defined as an extradural bleeding not evident at the first brain computed tomography (CT) scan performed after traumatic brain injury but evidenced by further radiologic evaluations. CASE DESCRIPTION: A 22-year-old male was admitted to our unit after brain injury due to an assault. Immediate brain CT scan revealed a right frontal epidural hematoma (EDH) and a smaller left anterior temporal EDH with multiple, bilateral skull fractures in the frontal, parietal, and temporal bones. Both EDHs were surgically treated in the same session. Another immediate CT scan showed a third left parietal acute DEDH. The patient was retransferred to the operating room for a further left parietal craniotomy and EDH evacuation. The postoperative period was uneventful: the patient effectively improved. After 15 days, the patient left the hospital and was admitted to a rehabilitation center. CONCLUSIONS: To the best of our knowledge, this is the first report of a synchronous acute bilateral EDH with the development of a third DEDH located in a separate site. This finding is certainly related to the presence of multiple and bilateral skull fractures. In our experience, we suggest performing an intraoperative CT scan, if available, to early detect the possible development of DEDH.

Importance of Veins for Neurosurgery as Landmarks Against Brain Shifting Phenomenon: An Anatomical and 3D-MPRAGE MR Reconstruction of Superficial Cortical Veins.

Modern neurosurgery uses preoperative imaging daily. Three-dimensional reconstruction of the cortical anatomy and of the superficial veins helps the surgeons plan and perform neurosurgical procedures much more safely. The target is always to give the patient maximum benefit in terms of outcome and minimize intraoperative and postoperative complications. This study aims to develop a method for the combined representation of the cerebral cortex anatomy and the superficial cerebral veins, whose integration is beneficial in daily practice. Only those patients who underwent surgical procedures with craniotomy and a large opening of the dura mater were included in this study, for a total of 23 patients, 13 females (56.5%) and 10 males (43.5%). The average age was 50.1 years. We used a magnetic resonance tomograph Magnetom Vision® 1.5T (Siemens AG). Two sequences were applied: a strongly T1-weighted magnetization-prepared rapid acquisition with gradient echo (MPRAGE) sequence to visualize cerebral anatomical structures, and a FLASH-2D-TOF angiography sequence to visualize the venous vessels on the cortical surface after the administration of a paramagnetic contrast agent. The two data sets were superimposed manually, co-registered in an interactive process, and merged to create a combined data set, segmented and visualized as a three-dimensional reconstruction. Furthermore, we present our method for visualizing superficial veins, which helps manage brain shift (BS). We also performed anatomical observations on the reconstructions. The reconstructions of the cortical and venous anatomy proved to be a valuable tool in surgical planning and positively influenced the surgical procedure. Due to the good correlation with the existing surgical site, this method should be validated on a larger cohort or in a multicentric study.

Slit-like hypertensive hydrocephalus: Report of a late, complex, and multifactorial complication in an oncologic patient.

BACKGROUND: Several sophisticated techniques and many chemotherapy drugs have improved life expectancy of oncologic patients allowing us to observe late complications which present many years after the initial treatment. CASE DESCRIPTION: We present a unique case of a patient affected by acute lymphoblastic leukemia at the age of 6 years, treated with whole brain radiotherapy and intrathecal chemotherapy, developing meningiomatosis and leptomeningeal alterations as late complications and the interaction of these two entities caused a peculiar form of hydrocephalus without ventricular dilation. The diagnosis of pseudotumor cerebri was excluded due the postradio/chemotherapy development of meningiomatosis, not present in a previously head magnetic resonance imaging, that exerted compression to the Sylvian aqueduct causing intracranial hypertension with papillary stasis without ventricles enlargement due to brain stiffness. Moreover, a peculiar intraoperative rubbery consistency of brain parenchyma was detected strengthening this complex diagnosis. CONCLUSION: At the best of our knowledge, this is the first report of obstructive hydrocephalus without ventricles dilation caused by brain stiffness related to late alterations of oncologic treatments. This report could be a guide for further complex patients diagnoses and for improving treatments efficacy.

Out-of-third ventricle colloid cysts: review of the literature on pathophysiology, diagnosis and treatment of an uncommon condition, with a focus on headache.

INTRODUCTION: Colloid cysts are rare benign intracranial lesions classically described as "third ventricle colloid cysts" because of their location within the third ventricle. These lesions' clinical and diagnostic features are mainly related to intermittent or persistent obstruction of foramina of Monro causing cerebrospinal fluid (CSF) circulation impairment and symptoms of raised intracranial pressure. Few reports on colloid cysts located outside the third ventricle have been published over the years. This paper aims to review the existing literature on out-of-third ventricle colloid cysts, and introduces a new illustrative case of lateral ventricle colloid cyst surgically managed with endoscopic technique. EVIDENCE ACQUISITION: A literature review was performed through a Medline web-search, using "colloid cysts," "lateral ventricle colloid cysts," "fourth ventricle colloid cysts," "brain colloid cyst," "spinal colloid cysts" as keywords. All retrieved abstracts were screened and full-length text of papers suitable for inclusion were examined. An illustrative case has been added to the existing literature. A 45-year-old man complaining of recurrent headache underwent conservative treatment for 4 years. The unusual headache features as well as the uncommon onset and association with episodic mental impairment led to an initial diagnosis of anxiety disorder triggering the headache. A further worsening of headache and the lack of significant clinical benefit prompted further investigation. Computed-tomography (CT) of the brain showed asymmetrical dilatation of the right lateral ventricle, due to the presence of a cystic mass obstructing the foramen of Monroe. Patient underwent endoscopic resection of the cyst. EVIDENCE SYNTHESIS: The literature review revealed 16 papers reported between 1952 and 2016. In all cases included histological diagnosis of colloid cyst had been obtained. Clinical and radiological features, as well as surgical management in each case have been analyzed. In the case here reported, histological examination documented a colloid cyst. The postoperative course was uneventful, with progressive resolution of headache. CONCLUSIONS: Despite third ventricle colloid cysts are related to typical clinical and diagnostic features, non-third ventricle colloid cysts may be responsible for unusual clinical presentation, so making a correct diagnostic approach challenging. We submit that in cases of recurrent headache with unusual features and lacking signs of neurological deficits, a rare neurosurgical condition as an "ectopic" colloid cyst should be included in the differential diagnosis.

Spontaneous Subgaleal Abscess Associated with Lung Adenocarcinoma: First Description of This Unusual Association.

BACKGROUND: Primary, spontaneous, or de novo subgaleal abscesses represent extremely rare lesions usually related to patients with risk factors and predisposing conditions for infections. They are associated with high morbidity, and a proper diagnosis can be misleading. To the best of our knowledge, this is the first reported case of a de novo subgaleal abscess not related to previous traumatic head injury and associated with lung adenocarcinoma. CASE DESCRIPTION: A 59-year-old man was admitted to our unit because he presented fever and a palpable subcutaneous right parietal mass. No history of traumatic head injury was mentioned. The patient underwent needle aspiration of the subgaleal lesion for microbiological, histological, and cytological examination, with negative response. Chest radiograph and then thoracic computed tomography scan revealed the presence of 2 lesions in the left lung. Complete removal with surgical debridement of the parietal bone lesion was performed due to the suspicion of an abscessualized skull metastasis from a primary lung adenocarcinoma. CONCLUSIONS: We strongly suggest a patient global assessment in the event of subgaleal abscess without history of traumatic head injury, to treat eventual associated findings as soon as possible.

Thoracic Intradural-Extramedullary Epidermoid Tumor: The Relevance for Resection of Classic Subarachnoid Space Microsurgical Anatomy in Modern Spinal Surgery. Technical Note and Review of the Literature.

BACKGROUND: Intradural epidermoid tumors of the spinal cord are commonly associated with spinal cord dysraphism or invasive procedures. We report the particular relationships between spinal subarachnoid compartments and thoracic intradural-extramedullary epidermoid tumor, highlighting the relevant anatomic changes that may influence microsurgery. METHODS: A 40-year-old woman from compressive myelopathy owing to a thoracic epidermoid tumor extending from T3 to T4 and not associated with spina bifida, trauma, previous surgery, or lumbar spinal puncture underwent microsurgical excision. Accurate tumor membrane dissection, respecting spinal arachnoidal compartments, was performed. Reposition of a laminoplasty plateau helped in restoring thoracic spine anatomic integrity. RESULTS: Safe gross total tumor resection was achieved. Complete neurologic recovery as well as absence of recurrent tumor was documented at 4-year follow-up. A literature review revealed only 2 other cases of "isolated" thoracic spine epidermoid tumor. However, description of the relationship between tumor membranes and spinal subarachnoid compartments was not available in either case. CONCLUSIONS: A thorough knowledge of spinal subarachnoid space anatomy is helpful to distinguish between tumor membranes and arachnoidal planes and to achieve a safe and complete resection to avoid recurrences.