Intraoperative Stereotactic Arteriography in Complex Cervical Spine Surgery.

Intra-operative navigation has revolutionized spinal instrumentation. The O-arm (a mobile X-ray system; Medtronic, Minneapolis, MN) is uniquely capable of enabling visualization of the spine in axial planes. The application of this technology is wide yet underutilized in terms of its capacity to image spinal vascular anatomy. We completed a retrospective chart review of the following case studies. A 24-year-old neurologically intact female presented with a Jefferson fracture without vertebral artery dissection after a motor vehicle accident. After the failure of conservative management due to pseudoarthrosis, the patient opted for fusion. Prior to the procedure, bilateral 5 French femoral sheaths were placed. After exposure, intraarterial (IA) contrast was injected prior to the O-arm spin to visualize both vertebral arteries, which were stretched and adjacent to a mobile boney segment. In the second case, a 71-year-old male presented with right shoulder pain and a flaccid left deltoid secondary to a large enhancing epidural lesion spanning C4-C7. Further work-up confirmed a diagnosis of metastatic intrahepatic cholangiocarcinoma. Prior to resection with cervical spinal stabilization, a right radial artery 4 French Glidesheath was placed. Prior to the O-arm spin, the right vertebral artery was selected, and intravenous contrast was injected to permit visualization of the vertebral artery, which was encased within the tumor and at significant risk for iatrogenic injury. Both patients tolerated the endovascular and spinal procedures well without vertebral artery injury. This is the first series to report the effective use of the O-arm for improved visualization of vascular anatomy during surgery for cervical spinal trauma and oncology.

Spinal Meningiomas: A Comprehensive Review and Update on Advancements in Molecular Characterization, Diagnostics, Surgical Approach and Technology, and Alternative Therapies.

Spinal meningiomas are the most common intradural, extramedullary tumor in adults, yet the least common entity when accounting for all meningiomas spanning the neuraxis. While traditionally considered a benign recapitulation of their intracranial counterpart, a paucity of knowledge exists regarding the differences between meningiomas arising from these two anatomic compartments in terms of histopathologic subtypes, molecular tumor biology, surgical principles, long-term functional outcomes, and recurrence rates. To date, advancements at the bench have largely been made for intracranial meningiomas, including the discovery of novel gene targets, DNA methylation profiles, integrated diagnoses, and alternative systemic therapies, with few exceptions reserved for spinal pathology. Likewise, evolving clinical research offers significant updates to our understanding of guiding surgical principles, intraoperative technology, and perioperative patient management for intracranial meningiomas. Nonetheless, spinal meningiomas are predominantly relegated to studies considering non-specific intradural extramedullary spinal tumors of all histopathologic types. The aim of this review is to comprehensively report updates in both basic science and clinical research regarding intraspinal meningiomas and to provide illustrative case examples thereof, thereby lending a better understanding of this heterogenous class of central nervous system tumors.

Anatomical Step-by-Step Dissection of Midline Suboccipital Approaches to the Fourth Ventricle for Trainees: Surgical Anatomy of the Telovelar, Transvermian, and Superior Transvelar Routes, Surgical Principles, and Illustrative Cases.

Introduction Safe, effective access to the fourth ventricle for oncologic resection remains challenging given the depth of location, restricted posterior fossa boundaries, and surrounding eloquent neuroanatomy. Despite description in the literature, a practical step-by step dissection guide of the suboccipital approaches to the fourth ventricle targeted to all training levels is lacking. Methods Two formalin-fixed, latex-injected specimens were dissected under microscopic magnification and endoscopic visualization. Dissections of the telovelar, transvermian, and supracerebellar infratentorial-superior transvelar approaches were performed by one neurosurgery resident (D.D.D.), under guidance of senior authors. The dissections were supplemented with representative clinical cases to highlight pertinent surgical principles. Results The telovelar and transvermian corridors afford excellent access to the caudal two-thirds of the fourth ventricle with the former approach offering expanded access to the lateral recess, foramen of Luschka, adjacent skull base, and cerebellopontine angle. The supracerebellar infratentorial-superior transvelar approach reaches the rostral third of the fourth ventricle, the cerebral aqueduct, and dorsal mesencephalon. Key steps described include positioning and skin incision, myofascial dissection, burr hole and craniotomy, durotomy, the aforementioned transventricular routes, and identification of relevant skull base landmarks. Conclusion The midline suboccipital craniotomy represents a foundational cranial approach, particularly for lesions involving the fourth ventricle. Operatively oriented resources that combine stepwise neuroanatomic dissections with representative cases provide a crucial foundation for neurosurgical training. We present a comprehensive guide for trainees in the surgical anatomy laboratory to optimize familiarity with fourth ventricle approaches, mastery of relevant microsurgical anatomy, and simultaneous preparation for learning in the operating room.

Trigeminal neuralgia pain outcomes following microsurgical resection versus stereotactic radiosurgery for petroclival meningiomas: a systematic review and meta-analysis.

OBJECTIVE: Petroclival meningiomas (PCMs) are challenging lesions to treat because of their deep location and proximity to critical neurovascular structures. Patients with these lesions commonly present because of local mass effect. A symptom that proves challenging to definitively manage is trigeminal neuralgia (TN), which occurs in approximately 5% of PCM cases. To date, there is no consensus on whether microsurgical resection or stereotactic radiosurgery (SRS) leads to better outcomes in the treatment of TN secondary to PCM. In this systematic review and meta-analysis, the authors aimed to evaluate the available literature on the efficacy of microsurgical resection versus SRS for controlling TN secondary to PCM. METHODS: The Embase, MEDLINE, Scopus, and Cochrane databases were queried from database inception to May 17, 2022, using the search terms "(petroclival AND meningioma) AND (trigeminal AND neuralgia)." Study inclusion criteria were as follows: 1) reports on patients aged ≥ 18 years and diagnosed with TN secondary to PCM, 2) cases treated with microsurgical resection or SRS, 3) cases with at least one posttreatment follow-up report of TN pain, 4) cases with at least one outcome of tumor control, and 5) publications describing randomized controlled trials, comparative or single-arm observational studies, case reports, or case series. Exclusion criteria were 1) literature reviews, technical notes, conference abstracts, or autopsy reports; 2) publications that did not clearly differentiate data on patients with PCMs from data on patients with different tumors or with meningiomas in different locations (other intracranial or spinal meningiomas); 3) publications that contained insufficient data on treatments and outcomes; and 4) publications not written in the English language. References of eligible studies were screened to retrieve additional relevant studies. Data on pain and tumor outcomes were compared between the microsurgical resection and SRS treatment groups. The DerSimonian-Laird random-effects model with Hartung-Knapp-Sidik-Jonkman variance correction was used to pool estimates from the included studies. RESULTS: Two comparative observational studies and 6 single-arm observational studies describing outcomes after primary intervention were included in the analyses (138 patients). Fifty-seven patients underwent microsurgical resection and 81 underwent SRS for the management of TN secondary to PCM. By the last follow-up (mean 71 months, range 24-149 months), the resection group had significantly higher rates of pain resolution than the SRS group (82%, 95% CI 50%-100% vs 31%, 95% CI 18%-45%, respectively; p = 0.004). There was also a significantly longer median time to tumor recurrence following resection (43.75 vs 16.7 months, p < 0.01). The resection group showed lower rates of pain persistence (0%, 95% CI 0%-6% vs 25%, 95% CI 13%-39%, p = 0.001) and pain exacerbation (0% vs 12%, 95% CI 3%-23%, p = 0.001). The most common postintervention Barrow Neurological Institute pain score in the surgical group was I (66.7%) compared with III (27.2%) in the SRS group. Surgical reintervention was less frequently required following primary resection (1.8%, 95% CI 0%-37% vs 19%, 95% CI 1%-48%, p < 0.01). CONCLUSIONS: Microsurgical resection is associated with higher rates of TN pain resolution and lower rates of pain persistence and exacerbation than SRS in the treatment of PCM. SRS with further TN management is a viable alternative in patients who are not good candidates for microsurgical resection.

The implications of antithrombotic agents on subdural hematoma evacuation: what does "reversal" truly entail?

OBJECTIVE: The optimal perioperative management of antithrombotic therapy (ATT) in patients requiring urgent neurosurgical intervention for subdural hematoma (SDH) is poorly understood. The delicate equilibrium of effective hemostasis while preventing thrombosis is complex and relies on numerous factors such as indication for and type of ATT, medical comorbidities, and extent of neurological injury. This study aimed to analyze the impact of ATT and reversal strategies on surgical outcomes to highlight current challenges in the management of these high-risk patients. METHODS: The authors performed a retrospective surgical cohort analysis of 100 patients undergoing urgent SDH evacuation at a level I trauma center between March 2020 and May 2021. The patients were first stratified into two cohorts based on preoperative ATT use and then further segregated by receipt of reversal agents. Statistical analysis included the chi-square test, Welch two-sample t-test, and multivariate logistic regression. The primary outcome was mortality. Secondary endpoints included radiographic SDH reexpansion, revision surgery, improvement in preoperative neurological deficits, and incidence of thromboembolism. A crossover cohort was secondarily analyzed in patients for whom ATT was interrupted for a minimum duration equal to effective drug metabolism. Finally, ATT reinitiation patterns were examined. RESULTS: Of 100 patients, 48% received ATT, 54.2% of whom were given reversal agents. ATT use was significantly associated with decreased rates of postoperative neurological improvement (p = 0.023) with trends toward increased mortality (p = 0.078), SDH reexpansion (p = 0.12), and need for revision surgery (p = 0.10). Patient crossover revealed a 4 times greater likelihood of death in patients without ATT interruption prior to surgery (p = 0.040) without an observable impact on secondary outcomes. ATT reversal contributed no improvement in outcomes other than a decreased intensive care unit length of stay when adjusted for in-hospital mortality (p = 0.014). The rate of postoperative thromboembolism following ATT reversal was 11.5%. ATT reinitiation was highly variable, occurring in 59.5% of patients, with median times of 17 and 15 days for antiplatelets and anticoagulants, respectively. CONCLUSIONS: Use of preoperative ATT portends poor clinical outcomes following nonelective SDH evacuation regardless of attempts to reverse these medications with replacement blood products. This study further reinforces the critical need for judicious use of ATT and optimization of reversal strategies in high-risk patient populations as best guided by multidisciplinary teams and evolving clinical practice guidelines.

Systematic Review of WHO Grade 4 Astrocytoma in the Cerebellopontine Angle: The Impact of Anatomic Corridor on Treatment Options and Outcomes.

Background Despite advances in multimodal oncologic therapies and molecular genetics, overall survival (OS) in patients with high-grade astrocytomas remains poor. We present an illustrative case and systematic review of rare, predominantly extra-axial World Health Organization (WHO) grade 4 astrocytomas located within the cerebellopontine angle (CPA) and explore the impact of anatomic location on diagnosis, management, and outcomes. Methods A systematic review of adult patients with predominantly extra-axial WHO grade 4 CPA astrocytomas was conducted following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines through December 2022. Results Eighteen articles were included comprising 21 astrocytomas: 13 exophytic tumors arising from the cerebellopontine parenchyma and 8 tumors originating from a cranial nerve root entry zone. The median OS was 15 months with one-third of cases demonstrating delayed diagnosis. Gross total resection, molecular genetic profiling, and use of ancillary treatment were low. We report the only patient with an integrated isocitrate dehydrogenase 1 (IDH-1) mutant diagnosis, who, after subtotal resection and chemoradiation, remains alive at 40 months without progression. Conclusion The deep conical-shaped corridor and abundance of eloquent tissue of the CPA significantly limits both surgical resection and utility of device-based therapies in this region. Prompt diagnosis, molecular characterization, and systemic therapeutic advances serve as the predominant means to optimize survival for patients with rare skull base astrocytomas.

Carrimycin, a first in-class anti-cancer agent, targets selenoprotein H to induce nucleolar oxidative stress and inhibit ribosome biogenesis.

Carrimycin is a synthetic macrolide antibiotic that has been shown to have anti-cancer activity; however, its exact mechanism of action and molecular target were previously unknown. It was recently elucidated that Isovalerylspiramycin I (ISP I), the active component of carrimycin, targets selenoprotein H (SelH), a nucleolar reactive oxygen species-scavenging enzyme in the selenoprotein family. ISP I treatment accelerates SelH degradation, resulting in oxidative stress, disrupted ribosomal biogenesis, and apoptosis in tumor cells. Specifically, ISP I disrupts the association between RNA polymerase I and ribosomal DNA in the nucleolus. This inhibits ribosomal RNA transcription and subsequent ribosomal assembly, which prevents cancer cells from sustaining elevated rates of protein synthesis and cellular proliferation that are necessary for tumor growth and malignancy. In this review, we (1) describe the historical categorization and evolution of anti-cancer agents, including macrolide antibiotics, (2) outline the discovery of SelH as a target of ISP I, and (3) summarize the ways in which carrimycin has been used both clinically and at the bench to date and propose additional potential therapeutic uses.

Anatomical step-by-step dissection of common approaches to the third ventricle for trainees: surgical anatomy of the anterior transcortical and interhemispheric transcallosal approaches, surgical principles, and illustrative pediatric cases.

PURPOSE: To create a high-quality, cadaver-based, operatively oriented resource documenting the anterior transcortical and interhemispheric transcallosal approaches as corridors to the third ventricle targeted towards neurosurgical trainees at all levels. METHODS: Two formalin-fixed, latex-injected specimens were dissected under microscopic magnification and endoscopic-assisted visualization. Dissections of the transcortical and transcallosal craniotomies with transforaminal, transchoroidal, and interforniceal transventricular approaches were performed. The dissections were documented in a stepwise fashion using three-dimensional photographic image acquisition techniques and supplemented with representative cases to highlight pertinent surgical principles. RESULTS: The anterior transcortical and interhemispheric corridors afford excellent access to the anterior two-thirds of the third ventricle with varying risks associated with frontal lobe versus corpus callosum disruption, respectively. The transcortical approach offers a more direct, oblique view of the ipsilateral lateral ventricle, whereas the transcallosal approach readily establishes biventricular access through a paramedian corridor. Once inside the lateral ventricle, intraventricular angled endoscopy further enhances access to the extreme poles of the third ventricle from either open transcranial approach. Subsequent selection of either the transforaminal, transchoroidal, or interforniceal routes can be performed through either craniotomy and is ultimately dependent on individual deep venous anatomy, the epicenter of ventricular pathology, and the concomitant presence of hydrocephalus or embryologic cava. Key steps described include positioning and skin incision; scalp dissection; craniotomy flap elevation; durotomy; transcortical versus interhemispheric dissection with callosotomy; the aforementioned transventricular routes; and their relevant intraventricular landmarks. CONCLUSIONS: Approaches to the ventricular system for maximal safe resection of pediatric brain tumors are challenging to master yet represent foundational cranial surgical techniques. We present a comprehensive operatively oriented guide for neurosurgery residents that combines stepwise open and endoscopic cadaveric dissections with representative case studies to optimize familiarity with third ventricle approaches, mastery of relevant microsurgical anatomy, and preparation for operating room participation.

A protocol for visualization of murine in situ neurovascular interfaces.

Mapping cranial vasculature and adjacent neurovascular interfaces in their entirety will enhance our understanding of central nervous system function in any physiologic state. We present a workflow to visualize in situ murine vasculature and surrounding cranial structures using terminal polymer casting of vessels, iterative sample processing and image acquisition, and automated image registration and processing. While this method does not obtain dynamic imaging due to mouse sacrifice, these studies can be performed before sacrifice and processed with other acquired images. For complete details on the use and execution of this protocol, please refer to Rosenblum et al.1.

Advantages of Short-Segment Fusion in the Surgical Management of Thoracolumbar Traumatic Fractures: A Case Series and Review of the Literature.

INTRODUCTION: Spine trauma is a common pathology that frequently requires neurosurgical intervention. Few studies have examined short-segment, 360-degree stabilization of traumatic thoracolumbar fractures. METHODS: A retrospective review was completed of adult and pediatric patients who underwent surgical correction for thoracolumbar fractures between December 2011 and December 2021. RESULTS: Forty patients met the inclusion criteria. The majority of patients presented with an American Spinal Injury Association (ASIA) score of D (n = 11) or E (n = 21). The most common level of injury was L1 (n = 20). The average length of stay was 11.7 days. Postoperatively, two patients had pulmonary emboli or deep venous thrombosis, and two had surgical site infections. Most patients were discharged to home (n = 21) or acute rehab (n = 14). The fusion rate at six months was 97.5%. Neurologically, all patients regained ambulation by >18 months follow-up. For the ASIA scale, most had a score of D (n = 4) or E (n = 32) at six months. The same trend was observed with the Frankel score, where most patients had either D (n = 5) or E (n = 31), improving to only two having a score of D at >18 months. CONCLUSIONS: Corpectomy followed by posterior fusion has a number of biomechanical benefits. This construct permits circumferential decompression, larger surface area for fusion, improved reconstitution of vertebral body height, reduced kyphosis, and an overall shorter segment. This results in fewer levels needing to be fused while enabling the greatest changes of successful fusion.

Epigenetic Regulation in Primary CNS Tumors: An Opportunity to Bridge Old and New WHO Classifications.

Originally approved in 1979, a specific grading classification for central nervous system (CNS) tumors was devised by the World Health Organization (WHO) in an effort to guide cancer treatment and better understand prognosis. These "blue books" have since undergone several iterations based on tumor location, advancements in histopathology, and most recently, diagnostic molecular pathology in its fifth edition. As new research methods have evolved to elucidate complex molecular mechanisms of tumorigenesis, a need to update and integrate these findings into the WHO grading scheme has become apparent. Epigenetic tools represent an area of burgeoning interest that encompasses all non-Mendelian inherited genetic features affecting gene expression, including but not limited to chromatin remodeling complexes, DNA methylation, and histone regulating enzymes. The SWItch/Sucrose non-fermenting (SWI/SNF) chromatin remodeling complex is the largest mammalian family of chromatin remodeling proteins and is estimated to be altered in 20-25% of all human malignancies; however, the ways in which it contributes to tumorigenesis are not fully understood. We recently discovered that CNS tumors with SWI/SNF mutations have revealed an oncogenic role for endogenous retroviruses (ERVs), remnants of exogenous retroviruses that integrated into the germline and are inherited like Mendelian genes, several of which retain open reading frames for proteins whose expression putatively contributes to tumor formation. Herein, we analyzed the latest WHO classification scheme for all CNS tumors with documented SWI/SNF mutations and/or aberrant ERV expression, and we summarize this information to highlight potential research opportunities that could be integrated into the grading scheme to better delineate diagnostic criteria and therapeutic targets.

Severe kyphoscoliosis correction utilizing sublaminar bands in the setting of a vertebral column resection: a unique technical report.

PURPOSE: Severe kyphoscoliosis produces combined coronal and sagittal imbalance, a challenging presentation of Adult Spinal Deformity (ASD). Vertebral column resection (VCR) provides three-dimensional correction typically reserved for severe and/or fixed deformities. The challenge of a VCR is to stabilize the spinal column during incremental reduction maneuvers to correct the deformity. We describe novel use of sub-laminar bands with a temporary pivoting rod construct to achieve coronal and sagittal correction in one reductive maneuver. METHODS: All available notes, imaging, and reports were summarized for inclusion. RESULTS: A 67-year-old male presented severe, progressive thoracolumbar kyphoscoliosis, subsequent back pain, and difficulty in ambulating. Given the progression, surgical intervention was undertaken. The patient underwent an L3 VCR followed by instrumentation from T2 to pelvis. Kyphoscoliosis correction was performed via a single reduction maneuver using novel pivoting-rod construct and sub-laminar bands followed by quad-rod construct placement. Fresh, frozen, femoral head allograft, and BMP were utilized. The patient was placed in a Jewett brace for 6 weeks postoperatively and recovered. His condition remains optimized at three-year follow-up. CONCLUSION: Correcting three-dimensional deformities can require vertebral column resection and pose risk during correction. We propose a sub-laminar band with a pivot-rod construct as a safe, effective technique, limiting the number of reduction maneuvers.

MN1 altered astroblastoma with APC and LRP1B gene mutations: a unique variant in the cervical spine of a pediatric patient.

PURPOSE: Astroblastomas (AB) are high-grade neoplasms which typically occur within the cerebral hemisphere. However, given the rarity of this neoplasm and the number of variants, the relevance of this molecular makeup is unknown. We sought to describe the clinical presentation, treatment, and pathological analysis of a novel MN1 (meningioma 1) cervical spinal cord astroblastoma variant presenting in a pediatric patient. METHODS: A retrospective review of electronic medical records was performed with an emphasis on neuroimaging, perioperative course, and pathological analysis. RESULTS: An 11-month-old male with no significant history presented with two weeks of neck stiffness and cervicalgia. Neurologically, the patient was intact without signs of infection or trauma. Cervical CT was unremarkable. A subsequent MRI demonstrated a heterogeneously enhancing intramedullary lesion extending from the craniocervical junction to T4. The patient was treated with perioperative steroids and underwent C1-C3 laminectomies and C4-T4 laminotomies for tumor resection. Upon completion of the durotomy, an exophytic gray-red tumor was appreciated within the epidural space and gross total resection was achieved (no change on intraoperative neurophysiological monitoring) and confirmed on post-operative imaging. Immunohistochemical analysis was consistent with an astroblastoma with atypical diffuse positivity of CD56, CD99, and nuclear OLIG2. Molecular analysis revealed not only MN1 alterations but also changes in genes encoding APC and LRP1B. Both alterations were not previously documented to be associated with an astroblastoma. CONCLUSION: Our case represents the first report of an infant with an MN1 astroblastoma with APC and LRP1B gene alterations in the cervical spine. Gross total resection paired with a detailed histopathologic analysis is vital for optimizing adjuvant treatment.

Acute worsening of CADASIL in a patient with COVID-19 infection: illustrative case.

BACKGROUND: Reports of cerebrovascular ischemia and stroke occurring as predominant neurological sequelae of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection, which causes coronavirus disease 2019 (COVID-19), are increasingly evident within the literature. While various pathophysiological mechanisms have been postulated, including hypercoagulability, endothelial invasion, and systemic inflammation, discrete mechanisms for viral neurotropism remain unclear and controversial. OBSERVATIONS: The authors present a unique case study of a 64-year-old male with acute COVID-19 infection and acute worsening of previously stable cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL), a rare heritable arteriopathy due to mutation in the Notch3 gene, which is critical for vascular development and tone. Delayed cranial neuropathies, brainstem fluid-attenuated inversion recovery signal, and enhancement of olfactory and vagus nerves on magnetic resonance neurography in this patient further support viral neurotropism via cranial nerves in addition to cerebral vasculature. LESSONS: To the authors' knowledge, this is the first case in the literature that not only demonstrates the consequences of COVID-19 infection in a patient with altered cerebrovascular autoregulation such as CADASIL but also highlights the tropism of SARS-CoV-2 for (1) cranial nerves as a mode of entry to the central nervous system and (2) vessels as a cause of cerebrovascular ischemia.

Osteoporosis as a Risk Factor for Intraoperative Complications and Long-term Instrumentation Failure in Patients With Scoliotic Spinal Deformity.

STUDY DESIGN: A retrospective review study. OBJECTIVE: This study aims to determine the effect of osteoporosis on spine instrumentation. SUMMARY OF BACKGROUND DATA: Osteoporosis is a common skeletal pathology that affects systemic cortical bone maintenance and remodeling. This disease accelerates the degeneration of the spine, often necessitating spinal surgery for progressive vertebral deformity, pathologic fracture, bony canal stenosis, and/or neural element decompression. There is a paucity of literature describing the role of osteoporosis as it relates to both perioperative complications and outcomes after spine fusion surgery. MATERIALS AND METHODS: A retrospective review was conducted of a prospectively maintained database for patients undergoing spine surgery between January 1, 2006 and October 3, 2017. Inclusion criteria included age 18 years and above and surgery performed for the correction of thoracolumbar scoliosis. Data collected included various demographic, clinical, and operative variables. RESULTS: A total of 532 patients met inclusion criteria, including 144 (27%) patients with a diagnosis of osteoporosis. Osteoporosis was significantly associated with increased blood volume loss (P=0.003). Postoperatively, osteoporosis was associated with increased rates of instrumentation failure (19% vs. 10%; P=0.008) and the need for revision surgery (33% vs. 16%; P<0.001). Multivariate analysis confirmed osteoporosis to be an independent risk factor for increased mean number of spinal segments fused (P<0.05), mean blood volume loss (P<0.05), rate of postoperative deep venous thrombosis/pulmonary embolism (P<0.05), rate of instrumentation failure (P<0.05), and need for revision surgery (P<0.05). CONCLUSION: Osteoporosis is a significant risk factor for instrumentation failure and need for revision surgery following arthrodesis for scoliosis correction. Furthermore, patients with osteoporosis have a significantly higher risk of intraoperative blood volume loss and postoperative thromboembolic events.

Operation "NeuroTeam": rendering the absolute best care for the most deserving patients under the most difficult conditions.

The tenets of neurosurgery worldwide, whether in the civilian or military sector, espouse vigilance, the ability to adapt, extreme ownership, and, of course, an innate drive for developing a unique set of technical skills. At a time in history when the complexity of battlefield neurotrauma climaxed coupled with a chronic shortage of military neurosurgeons, modernized solutions were mandated in order to deliver world-class neurological care to our servicemen and servicewomen. Complex blast injuries, as caused by an increased incidence of improvised explosive devices, yielded widespread systemic inflammatory responses with multiorgan damage. In response to these challenges, the "NeuroTeam," originally a unit of two neurosurgeons as deployed during Operation Desert Storm, was redesigned to instead pair a neurosurgeon with a neurointensivist and launched itself during two specialized missions in Operations Iraqi Freedom and Enduring Freedom. Representing a hybridized version of present-day neurocritical care teams, the purpose of this unit was to optimize neurosurgical care by focusing on interdisciplinary collaboration in an Echelon III combat support hospital. The NeuroTeam provided unique workflow capabilities never seen collectively on the battlefield: downrange neurosurgical capability by a board-certified neurological surgeon within 60 minutes from the point of injury paired with a neurocritical care-trained intensivist. This also set the stage for intraoperative telemedicine infrastructure for neurosurgery and optimized the ability to evaluate, triage, and stabilize patients prior to medical evacuation. This novel military partnership ultimately allowed the neurosurgeon to focus on the tenets of the craft and thereby the dynamic needs of the patient first and foremost. Since the success of these missions, the NeuroTeam has evolved into a detachable unit, the "Head and Neck Team," comprising neurosurgeons, otolaryngologists, and ophthalmologists, supported by a postinjury hospital unit, which includes an embedded neurocritical care physician. The creation and evolution of the NeuroTeam, necessitated by a shortage of military neurosurgeons and the dangerous shift in military wartime tactics, best exemplifies multidisciplinary collaboration and military medicine agility. As neurocritical care continues to evolve into a highly complex, distinct specialty, the lessons learned by the NeuroTeam ultimately serve as a reminder for civilian and military physicians alike. Despite the conditions and despite one's professional ego, patients with highly complex morbid neurological disease deserve expert, multidisciplinary management for survival.

Acute Spinal Cord Injury Due to Epidural Lipomatosis Without Osseous Injury.

Spinal epidural lipomatosis (SEL) is a common pathology of the lumbar spine. While the natural history is not well understood, there is a strong association with metabolic syndrome and endocrine dysfunction. Clinical presentation typically involves slow, progressive onset of radicular and myelopathic symptoms. Treatment primarily consists of weight loss, while surgery is reserved for refractory cases or acute cauda equina syndrome. We present a case of acute spinal cord injury (SCI) after trauma with underlying SEL in the cervicothoracic spine. Additionally, a literature review using a MEDLINE search of the English literature through April 2020 following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines was performed to identify all documented cases of acute spinal cord injury with underlying SEL. A 72-year-old obese male with insulin-dependent diabetes mellitus presented with subacute bilateral lower extremity weakness after a fall with a flank injury three days prior to evaluation. Within hours of admission, the patient acutely progressed to paraplegia and sensory loss below the T6 level consistent with an ASIA (American Spinal Injury Association) A spinal cord injury. No fracture or dislocation was identified on CT imaging. MRI of the thoracic spine revealed spinal cord compression secondary to extensive posterior epidural lipomatosis with resultant anterior displacement of the thecal sac. The patient underwent emergent T2-T9 laminectomy for decompression. Post-operatively, the patient regained sensation below the level of injury. A review of the literature reviewed no published articles on cases of complete spinal cord injury secondary to underlying SEL without associated fracture. Finally, we present the first report of an acute spinal cord injury in the setting of SEL without fracture. Our case demonstrates that SEL outside the lumbar spine confers increased risk for SCI following trauma. Patients with cervicothoracic SEL may require close neurological observation and timely surgical decompression.

Superior Ophthalmic Vein Flow Patterns as a Marker of Venous Sinus Stenosis and Hypertension in Idiopathic Intracranial Hypertension: A Case of Emergent Transverse Sinus Stenting as Treatment of Fulminant Idiopathic Intracranial Hypertension.

BACKGROUND: Fulminant idiopathic intracranial hypertension (IIH) can cause rapid vision loss. Transverse sinus stenosis is a finding commonly associated with IIH, and transverse sinus stenting has been used to rapidly reduce intracranial pressure and improve visual symptoms. Our objective was to describe a case of immediate alteration in reversed superior ophthalmic vein (SOV) flow in a fulminant IIH patient who underwent venous sinus stenting. METHODS: All charts, imaging, and notes spanning from the initial presentation to the post-intervention follow-up were reviewed and summarized for inclusion. RESULTS: A 24-year-old woman presented with several weeks of severe headaches and progressive vision loss. She was found to have severe papilledema and the opening pressure on lumbar puncture (LP) was 70 mm Hg. Computed tomography (CT) and magnetic resonance imaging demonstrated findings consistent with elevated intracranial pressure, and CT venography revealed stenosis of the right transverse sinus. She underwent an uncomplicated diagnostic cerebral angiogram, right venous sinus manometry, and right transverse to sigmoid sinus stenting procedure. Prior to deployment of the stent, a trans-stenotic pressure gradient of 12 mm Hg was observed within the right transverse-sigmoid junction, and flow through the bilateral SOVs was retrograde. Following stent placement, the pressure gradient normalized, and SOV flow was bidirectional. She subjectively reported improved vision, and there was improving papilledema. Repeat LP yielded an opening pressure of 21.6 mm Hg. CONCLUSIONS: This case demonstrates reversed SOV flow should be considered an indicator of severe venous sinus stenosis, and restoration to normal or near normal state following stenting for IIH is likely indicative of procedural success.

Lateral Femoral Cutaneous Nerve Angiomyoma.

Angiomyomas are benign tumors derived from smooth muscle cells of vessels. They are principally a pathology of the peripheral nervous system where they involve cutaneous nerves, causing pain and paresthesia. We present a case of a lateral femoral cutaneous nerve angiomyoma and its surgical treatment. A 24-year-old female presented to clinic with right thigh pain in the distribution of the lateral femoral cutaneous nerve, which had been ongoing and progressive for seven months. There was associated numbness and tingling. A lesion was noted in the anterior subcutaneous tissues of the thigh on contrasted CT and MRI. The patient was taken to the operating room where a pearly white lesion was found within the subcutaneous tissue. No effect was seen with stimulation of the lesion. The lesion was removed en bloc, and pathological analysis revealed an angiomyoma. Post-operatively, the patient reported complete resolution of all symptoms, namely, pain and paresthesia. No similar reports were identified within the literature. Together, angiomyomas have been described within the lower extremities to cause pain and paresthesia. This is the first reported case of an angiomyoma involvement within the lateral femoral cutaneous nerve. Complete surgical resection, in this case, was curative and diagnostic.

Guidelines in the management of CNS tumors.

INTRODUCTION: Evidence-based, clinical practice guidelines in the management of central nervous system tumors (CNS) continue to be developed and updated through the work of the Joint Section on Tumors of the Congress of Neurological Surgeons (CNS) and the American Association of Neurological Surgeons (AANS). METHODS: The guidelines are created using the most current and clinically relevant evidence using systematic methodologies, which classify available data and provide recommendations for clinical practice. CONCLUSION: This update summarizes the Tumor Section Guidelines developed over the last five years for non-functioning pituitary adenomas, low grade gliomas, vestibular schwannomas, and metastatic brain tumors.