Characterization of spinal hemangioblastomas in patients with and without von Hippel-Lindau, and YAP expression.

INTRODUCTION: Hemangioblastoma (HB) is a benign tumor of the central nervous system, associated with von Hippel-Lindau disease (VHL), or sporadic. The aim of this study was to compare and examine the clinical-pathological profile of patients with spinal hemangioblastoma and YAP expression. METHODS: A retrospective, descriptive, comparative study. All patients who underwent surgery for spinal HB between 2016 and 2023 were included. Clinical and radiological data were collected and analyzed. An immunohistochemistry panel including NeuN, neurofilaments (NF), and YAP-1, was performed. RESULTS: Nine patients were studied, six women and three men. Four patients had previously diagnosed VHL. The tumor location included: four cervical (44.44%), two thoracic (22.22%), two pontine with cervical extension (22.22%) and one patient with two lesions, one cervical and one thoracic (11.11%). Non-significant clinical differences were identified between VHL and sporadic patients. Imaging evidenced seven extramedullary and three intramedullary tumors. Histologically, intra-tumoral and perivascular axonal tracts were observed in all cases. One third of the tumors (two with VHL and one sporadic) presented extramedullary hematopoiesis. Seven cases (77.8%) expressed nuclear YAP (three with VHL and four sporadic HBs). The surgical outcome was good and only one patient with VHL undergoing subtotal resection had recurrence. CONCLUSIONS: Spinal HBs can be associated with VHL or be sporadic. To the best of our knowledge, this is the first study to describe YAP expression in HB. It is important to investigate the involvement of the Hippo pathway in HBs as a possible therapeutic target.

Holocord pilocytic astrocytoma in a young woman with intracranial extension: case report and review of the MRI characteristics.

INTRODUCTION: Pilocytic astrocytoma is a low-grade glioma more frequently seen in patients <20. It is pretty uncommon in the spinal cord. Rarely, astrocytoma may involve the most or total length of the spinal cord; in that case, they are called "holo-cord astrocytoma." In this case report, we are reporting the third holo-cord pilocytic astrocytoma in an adult patient and the first with an extension to the Magendie foramen. CASE PRESENTATION: We presented a 24-year-old woman with complaints of progressively worsening neck and back pain since one year ago. The patient's MRI showed a very large intradural and intramedullary cystic lesion with a solid component within the spinal cord extending from the medulla to the conus medullaris. Partial resection of the solid part of the cervical portion of the tumor was performed. Histopathological evaluation of the resected tumor segments was compatible with grade I pilocytic astrocytoma. After one year of follow-up, neck and back pain has reduced, and neurological functions have improved. CONCLUSION: Spinal cord pilocytic astrocytoma may present as a holo-cord tumor and can rarely extend to the intracranial fossa. Although this tumor does not arise from the central canal, in this case, it was extended through the Magendie foramen. Symptoms could be subtle despite extensive cord involvement. On MRI, this tumor presents as an intramedullary holo-cord cystic lesion intermixed with a solid component with a variable enhancement of the solid component.

Malignant melanotic schwannoma of the cervical spinal cord: a case report.

Spinal cord malignant melanotic schwannoma (MMNST) is a rare central nervous system tumor that originates from the spinal cord or spinal myelin sheath cells and can produce melanin. This type of tumor is usually highly aggressive and malignant, with a poor prognosis. The clinical manifestations of spinal cord MMNST are mainly pain, paresthesia, muscle weakness, muscle atrophy, etc., and symptoms of spinal cord compression, such as intestinal and bladder dysfunction, paraplegia, etc. Early detection of tumor lesions can facilitate tumor removal, improve patients' quality of life, and prolong patients' survival. In this case report, a 27-year-old young woman was diagnosed with MMNST of the cervical spinal cord due to weakness of her limbs in our hospital, and underwent surgical resection. The patient's limbs returned to normal after surgery. It is worth mentioning that the patient visited our hospital 7 months ago for "right upper limb pain for 3 days" and was diagnosed with a cervical spine space-occupying lesion at the same position this time, but the pathology report was "hemosiderosis". The patient's limbs returned to normal after surgery. It is worth mentioning that the patient visited our hospital 7 months ago for "right upper limb pain for 3 days" and was diagnosed with a cervical spine space-occupying lesion at the same position this time, but the pathology report was "hemosiderosis". This case report aims to raise awareness of the problem of spinal cord MMNST and contribute to greater knowledge of this rare tumor. This case report aims to raise awareness of the problem of spinal cord MMNST and contribute to greater knowledge of this rare tumor.

Evaluation of Conditions for the Development of Cryogenic Spinal Cord Injury Using a Canine Model: An Experimental Study on the Safety of Cryoablation for Metastatic Spinal Tumors.

BACKGROUND AND PURPOSE: Although the application of cryoablation to metastatic spinal tumors has been attempted, spinal cryoablation has the unique complication of cryogenic spinal cord injury. This study aimed to elucidate the conditions for the development of cryogenic spinal cord injury. MATERIALS AND METHODS: Fifteen canines were used in this study. A metal probe was inserted into the 13th thoracic vertebral body. Cryoablation was performed for 10 minutes by freezing the probe in liquid nitrogen. The control canine underwent probe insertion only. Spinal cord monitoring, epidural temperature measurement, motor function assessment, and pathologic examination of the spinal cord were performed. RESULTS: During the 10 minutes of cryoablation, the epidural temperature decreased and reached the lowest epidural temperature (LET) at the end of cryoablation. The LETs (degrees celsius [°C]) of each canine were -37, -30, -27, -8, -3, -2, 0, 1, 4, 8, 16, 18, 20, and 25, respectively. As the epidural temperature decreased, waveform amplitudes also decreased. At the end of cryoablation (10 minutes after the start of cryoablation), abnormal waves were observed in 92.9% (13/14) of canines. With epidural rewarming, the amplitude of the waveforms tended to recover. After epidural rewarming (2 hours after the start of cryoablation), abnormal waves were observed in 28.6% (4/14) of canines. The LETs (°C) of the canines with abnormal waves after epidural rewarming were -37, -30, -27, and -8. None of the canines with normal waves after epidural rewarming had any motor impairment. In contrast, all canines with remaining abnormal waves after epidural rewarming had motor impairment. In the pathologic assessment, cryogenic changes were found in canines with LETs (°C) of -37 -30, -27, -8, 0, and 1. CONCLUSIONS: This study showed that 10-minute spinal cryoablation with LETs (°C) of -37, -30, -27, -8, 0, and 1 caused cryogenic spinal cord injury. There was no evidence of cryogenic spinal cord injury in canines with LET of ≥4°C. The epidural temperature threshold for cryogenic spinal cord injury is between 1 and 4°C, suggesting that the epidural temperature should be maintained above at least 4°C to prevent cryogenic spinal cord injury.

Acute Macrocystic Thoracic Schwannoma: Systematic Review and Illustrative Case Example.

BACKGROUND: Schwannomas are benign peripheral nerve sheath tumors arising from myelinating Schwann cells. Although macrocystic changes are regularly encountered in schwannoma variants such as vestibular nerve tumors, they are exceedingly rare among spinal neoplasms. METHODS: Case report and systematic review of 4 databases (Ovid Medline, PubMed, Science Direct, and SCOPUS) from inception to present. All peer-reviewed publications reporting intradural cystic thoracic schwannoma were included. RESULTS: We identified 8 publications documenting 9 cases of cystic thoracic schwannoma. Four were female, 5 male; median age was 41 years (range, 27-80). Presentations ranged from incidental to pain, sensory changes, lower extremity paresis, or bowel/bladder dysfunction. Characteristic radiographic findings included T1 hypointensity, T2 hyperintensity, and cord effacement or compression. The present case followed a similar pattern: a 52-year-old male presented with worsening bilateral lower extremity weakness, low back pain, and gait dysfunction, worsening over 3 days. Examination also revealed decreased left lower extremity sensation. Imaging identified a well-delineated intradural, extramedullary macrocystic extending over T7-T10. The patient underwent a laminectomy resulting in complete tumor resection and restoration of intact neurologic function. Final pathology confirmed benign cystic schwannoma. CONCLUSIONS: Macrocystic thoracic schwannomas are exceedingly rare and lack a comprehensive scheme for clinical classification of their natural history and pathogenesis. We report the 10th case of such a schwannoma, and the first associated systematic review. Although macrocystic thoracic schwannomas are not frequently encountered, accurate diagnosis and appropriate neurosurgical treatment is critical in these vulnerable patients, given the opportunity for excellent functional outcomes following neurosurgical treatment.

Clinical presentation and extent of resection impacts progression-free survival in spinal ependymomas.

PURPOSE: Primary treatment of spinal ependymomas involves surgical resection, however recurrence ranges between 50 and 70%. While the association of survival outcomes with lesion extent of resection (EOR) has been studied, existing analyses are limited by small samples and archaic data resulting in an inhomogeneous population. We investigated the relationship between EOR and survival outcomes, chiefly overall survival (OS) and progression-free survival (PFS), in a large contemporary cohort of spinal ependymoma patients. METHODS: Adult patients diagnosed with a spinal ependymoma from 2006 to 2021 were identified from an institutional registry. Patients undergoing primary surgical resection at our institution, ≥ 1 routine follow-up MRI, and pathologic diagnosis of ependymoma were included. Records were reviewed for demographic information, EOR, lesion characteristics, and pre-/post-operative neurologic symptoms. EOR was divided into 2 classifications: gross total resection (GTR) and subtotal resection (STR). Log-rank test was used to compare OS and PFS between patient groups. RESULTS: Sixty-nine patients satisfied inclusion criteria, with 79.7% benefitting from GTR. The population was 56.2% male with average age of 45.7 years, and median follow-up duration of 58 months. Cox multivariate model demonstrated significant improvement in PFS when a GTR was attained (p <.001). Independently ambulatory patients prior to surgery had superior PFS (p <.001) and OS (p =.05). In univariate analyses, patients with a syrinx had improved PFS (p =.03) and were more likely to benefit from GTR (p =.01). Alternatively, OS was not affected by EOR (p =.78). CONCLUSIONS: In this large, contemporary series of adult spinal ependymoma patients, we demonstrated improvements in PFS when GTR was achieved.

Ependymomas of the spinal region in adults: Clinical and pathological features and MYCN expression levels in spinal ependymomas and myxopapillary ependymomas.

BACKGROUND: Ependymomas (EPNs) of the spinal region are a heterogeneous group of tumors that account for 17.6 % in adults. Four types have been recognized: subependymoma, spinal ependymoma (Sp-EPN), myxopapillary ependymoma (MPE), and Sp-EPN-MYCN amplified, each with distinct histopathological and molecular features. METHODS: This study investigated the clinical and pathological characteristics and MYCN expression levels of 35 Sp-EPN and MPE cases diagnosed at a tertiary university hospital over a decade-long period. RESULTS: Twenty-five cases were Sp-EPN and 10 cases were MPE, and were graded as WHO grade 2, except for 1 Sp-EPN case with grade 3 features. The most common symptoms were lower back pain and difficulty in walking. Radiology showed different tumor sizes and locations along the spinal cord, with MPEs exclusively in the lumbosacral region. Surgery was the main treatment, and gross total resection was achieved in all cases except for one. Immunohistochemistry showed low Ki-67 proliferation indices in all cases, and no MYCN expression. During follow-up, 3 (8.6 %) cases recurred and/or metastasized and 5 cases (14.3 %) died. No significant difference was found in disease-free survival or overall survival between Sp-EPN and MPE cases. However, 3 cases with grade 2 histology demonstrated recurrence and/or metastasis, despite the lack of MYCN expression. CONCLUSION: Our results underscore the multifactorial nature of tumor aggressiveness in EPNs of the spinal region. This study enhances our knowledge of the clinical and pathological features of Sp-EPNs and MPEs and highlights the need for better diagnostic and prognostic markers in these rare tumors.

Spinal intradural microsurgery in a nascent neurosurgical department: Lessons learned from the first 25 cases.

BACKGROUND: Between 2017 and 2021, the newly established Department of Neurosurgery at Shaare Zedek Medical Center in Jerusalem, a high volume metropolitan hospital, operated on 25 intradural lesions in 24 patients (one patient had multiple tumors). In this retrospective study, we review results and lessons learned as experienced surgeons opened a new service line. METHODS: A multidisciplinary team was assembled and led by experienced neurosurgeons with skills in both microneurosurgery and complex spine care. Standard operative techniques were used. A chart review was done to assess complications and outcome. RESULTS: 25 lesions were reviewed in 24 patients (14 female; 10 male) between the ages of 11-82 years of age. In 14 cases, gross total resection (GTR) was achieved; 11 cases underwent partial resection. Of the 11 non-GTR cases, 3 were initially planned as biopsies. In one case, there was a significant neurologic decline directly related to surgery. In a separate case, there was iatrogenic instability, necessitating further treatment. CONCLUSIONS: We identify six lessons learned in a nascent neurosurgical department, noting that surgical excellence is of paramount importance, but that the surgeon must also expand his/her role from master technician to team leader. Both microsurgical expertise for neural anatomy and understanding of spinal biomechanics for osseous anatomy is mandatory for surgery of SIDT. This retrospective analysis of our case series demonstrates experienced neurosurgeons can successfully deploy a new service line for challenging cases to the benefit of the hospital and local community.

Capillary Hemangioma of the Spinal Cord: Case Report and Systematic Review of Literature.

BACKGROUND: Capillary hemangiomas are rare vascular lesions that rarely affect the central nervous system. When they present within the spinal canal, they are typically confined intradurally, with intramedullary extension rare. We present a rare case of spinal intramedullary capillary hemangioma, with a systematic review of the literature. METHODS: Medical records and imaging data were retrospectively reviewed using the health record software EPIC (Verona, Wisconsin, USA) and the radiology management software system RIS/PACS (Radiology Information System/Picture Archiving and Communication System; QREADS). The report was written in accordance with the CARE (case reports) guidelines. We also performed a systematic review of the literature on all cases of intramedullary spinal capillary hemangiomas in accordance with PRISMA (preferred reporting items for systematic reviews and meta-analyses) guidelines. RESULTS: We report a case of a 54-year-old man who presented with progressive paraplegia and sensory deficits in the lower extremities. Spinal magnetic resonance imaging showed an intramedullary enhancing lesion centered at T11 with associated spinal cord compression. He underwent thoracic laminectomy and gross total resection of the lesion without complications and subsequent improvement on his neurological examination. Histological examination showed findings consistent with a capillary hemangioma. The literature review also documented 21 studies with a combined total of 38 cases of intramedullary spinal capillary hemangioma. CONCLUSIONS: Purely intramedullary capillary hemangiomas are unusual spinal lesions with only a few cases reported in the literature. These should be considered in the differential diagnosis of intramedullary tumors. Surgical management remains the first line of treatment for symptomatic patients.

Implications of DNA Methylation Classification in Diagnosing Ependymoma.

BACKGROUND: Ependymoma is a central nervous system (CNS) tumor that arises from the ependymal cells of the brain's ventricles and spinal cord. The histopathology of ependymomas is indistinguishable regardless of the site of origin, and the prognosis varies. Recent studies have revealed that the development site and prognosis reflect the genetic background. In this study, we used genome-wide DNA methylation array analysis to investigate the epigenetic background of ependymomas from different locations treated at our hospital. METHODS: Four cases of posterior fossa ependymomas and 11 cases of spinal ependymomas were analyzed. RESULTS: DNA methylation profiling using the DKFZ methylation classifier showed that the methylation diagnoses of the 2 cases differed from the histopathological diagnoses, and 2 cases could not be classified. Tumor that spread from the brain to the spinal cord was molecularly distinguishable from other primary spinal tumors. CONCLUSIONS: Although adding DNA methylation classification to conventional diagnostic methods may be helpful, the diagnosis in some cases remains undetermined. This may affect decision-making regarding treatment strategies and follow-up. Further investigations are required to improve the diagnostic accuracy of these tumors.

[Minimally invasive surgical treatment of extramedullary tumors at the level of craniovertebral junction: experience of the Burdenko Neurosurgical Center]. / Minimal'no invazivnoe khirurgicheskoe lechenie patsientov s ekstramedullyarnymi opukholyami na urovne kraniovertebral'nogo perekhoda: opyt NMITs neirokhirurgii im. akad. N.N. Burdenko.

OBJECTIVE: To describe own experience of treating patients with extramedullary tumors at the level of craniovertebral junction using minimally invasive surgical approaches. MATERIAL AND METHODS: The study included 29 patients who underwent minimally invasive microsurgical resection of extramedullary tumors at the level of craniovertebral junction. We analyzed the main clinical and surgical parameters. RESULTS: Gross total resection was achieved in most patients with high degree of safety. Two patients required redo surgery due to CSF leakage and soft tissue cyst. Mean length of hospital-stay was 7 days. VAS score of pain syndrome at discharge was 2 points and 0 points after 3 months. No significant differences in neurophysiological monitoring indicators were observed (p=0.76). CONCLUSION: Minimally invasive posterior approaches to extramedullary tumors at the level of craniovertebral junction can significantly reduce surgical trauma with equal extent of resection.

Digital 3D Exoscope is Safe and Effective in Surgery for Intradural Extramedullary Tumors: A Comparative Series.

BACKGROUND: Digital 3D exoscopes have been shown to be comparably safe and effective as surgical microscopes in complex microneurosurgical procedures. However, the results of exoscopic spinal tumor surgeries are scarce. The purpose of this study is to compare results of a transition from microscope to exoscope in surgeries for spinal intradural extramedullary tumors. METHODS: We included all consecutive patients with intradural extramedullary spinal tumors operated on by the senior author during January 2016 to October 2023. The 3D exoscope was used in the latter half of the series from November 2020. We evaluated pre- and postoperative clinical findings, imaging studies, intra- and postoperative events, and analyzed surgical videos from the operations retrospectively. RESULTS: We operated 35 patients (exoscope n = 19, microscope n = 16) for intradural extramedullary tumors (meningioma n = 18, schwannoma n = 12, other n = 5). Tumors in the cervical and thoracic spine were more common than in the lumbar region. The duration of surgery was slightly longer (median 220 vs. 185 minutes) in the exoscope group. However, the rate of gross total resection of the tumor was higher (81% vs. 67%) and the tumors more often located anteriorly to the spinal cord (42% vs. 13%) in the exoscope group. No major complications (i.e., permanent motor deficit or postoperative hematoma) occurred in either group. We saw postoperative gait improvement in 81% and 85% of the patients with preoperative deterioration of gait after exoscopic and microscopic surgeries, respectively. CONCLUSIONS: This study demonstrates that exoscope-assisted surgery for spinal intradural extramedullary tumors is comparable in safety and effectiveness to traditional microscopic surgery.

MYCN immunohistochemistry as surrogate marker for MYCN-amplified spinal ependymomas.

MYCN (master regulator of cell cycle entry and proliferative metabolism) gene amplification defines a molecular subgroup of spinal cord ependymomas that show high-grade morphology and aggressive behavior. Demonstration of MYCN amplification by DNA methylation or fluorescence-in situ hybridization (FISH) is required for diagnosis. We aimed to (i) assess prevalence and clinicopathological features of MYCN-amplified spinal ependymomas and (ii) evaluate utility of immunohistochemistry (IHC) for MYCN protein as a surrogate for molecular testing. A combined retrospective-prospective study spanning 8 years was designed during which all spinal cord ependymomas with adequate tissue were subjected to MYCN FISH and MYCN IHC. Among 77 spinal cord ependymomas included, MYCN amplification was identified in 4 samples from 3 patients (3/74, 4%) including two (1st and 2nd recurrences) from the same patient. All patients were adults (median age at diagnosis of 32 years) including two females and one male. The index tumors were located in thoracic (n = 2) and lumbar (n = 1) spinal cord. One of the female patients had neurofibromatosis type 2 (NF2). All four tumors showed anaplastic histology. Diffuse expression of MYCN protein was seen in all four MYCN-amplified samples but in none of the non-amplified cases, thus showing 100% concordance with FISH results. On follow-up, the NF2 patient developed widespread spinal dissemination while another developed recurrence proximal to the site of previous excision. To conclude, MYCN-amplified spinal ependymomas are rare tumors, accounting for ~ 4% of spinal cord ependymomas. Within the limitation of small sample size, MYCN IHC showed excellent concordance with MYCN gene amplification.

Pediatric spinal ependymoma with chromothripsis of chromosome 6: a case report and review of the literature.

BACKGROUND: Ependymomas are the third most common central nervous system tumor in the pediatric population; however, spinal ependymomas in children are rare. Ependymomas affecting the spinal cord most frequently occur in adults of 20-40 years of age. The current World Health Organization classification system for ependymomas is now composed of ten different entities based on histopathology, location, and molecular studies, with evidence that the new classification system more accurately predicts clinical outcomes. CASE PRESENTATION: We present the case of a 16-year-old Caucasian female patient with a history of type 2 neurofibromatosis with multiple schwannomas, meningioma, and spinal ependymoma. Chromosome analysis of the harvested spinal ependymoma tumor sample revealed a 46,XX,-6,+7,-22,+mar[16]/46,XX[4] karyotype. Subsequent OncoScan microarray analysis of the formalin-fixed paraffin-embedded tumor sample confirmed + 7, -22 and clarified that the marker chromosome represents chromothripsis of the entire chromosome 6 with more than 100 breakpoints. Fluorescent in situ hybridization and microarray analysis showed no evidence of MYCN amplification. The final integrated pathology diagnosis was spinal ependymoma (central nervous system World Health Organization grade 2 with no MYCN amplification. CONCLUSION: This case adds to the existing literature of pediatric patients with spinal ependymomas and expands the cytogenetic findings that may be seen in patients with this tumor type. This case also highlights the value of cytogenetics and microarray analysis in solid tumors to provide a more accurate molecular diagnosis.

Resection of an Intradural Intramedullary C7-T1 Tumor: Technical Nuances and Complication Management.

Primary spinal cord tumors are relatively rare, comprising approximately 4%-16% of all tumors originating from the central nervous system. These tumors are anatomically separable into 2 broad categories: intradural intramedullary and intradural extramedullary. Intramedullary tumors are composed predominantly of gliomas (infiltrative astrocytoma) and ependymomas.1-4 The primary treatment approach for these tumors is surgical resection, aiming to preserve neurologic function.5-9 In Video 1, the authors showcase a step-by-step approach for microsurgical resection of a primary spinal ependymoma, with emphasis on microsurgical technique and utility of adjunct equipment, such as intraoperative ultrasound and neuromonitoring.10,11 The patient consented to the procedure.

Usefulness of magnetic resonance imaging characteristics in discriminating H3 K27M-mutant gliomas from wildtype gliomas in spinal cord.

AIM: The aim of this study was to determine the usefulness of magnetic resonance imaging (MRI) characteristics in discriminating H3 K27M-mutant gliomas from wildtype gliomas in the spinal cord. MATERIALS AND METHODS: Fifty-eight patients with spinal cord gliomas were enrolled in this study. The H3 K27 gene status was identified by Sanger sequencing or immunohistochemistry test of resection tumor specimens. The MR imaging characteristics were evaluated and compared between H3 K27M-mutant and wildtype gliomas using the χ2 test and the Mann-Whitney U test. RESULTS: Of 58 recruited patients, 23 (39.7%) were diagnosed with H3 K27M-mutant glioma. The H3 K27M-mutant gliomas were found to more likely occur in men compared with wildtype gliomas (87.0% vs. 42.9%, p = 0.001). On T2-weighted MR images, the signal-to-noise ratio (SNR) of H3 K27M-mutant gliomas was significantly lower than that of wildtype gliomas (103.9 ± 72.0 vs. 168.9 ± 86.8, p < 0.001). Of 35 wildtype tumors, 60% showed well-defined margin but this feature was not found in all mutant tumors (p < 0.001). The SNR of tumors on contrast-enhanced T1-weighted images of the H3 K27M-mutant gliomas was significantly lower than that of wildtype gliomas (187.7 ± 160.4 vs. 295.1 ± 207.8, p = 0.006). Receiver operating-characteristic analysis revealed that area under curve (AUC) of combination of 1/SNR on T2-weighted images, 1/SNR on contrast-enhanced T1-weighted images, ill-defined margin, and sex reached 0.937 (95% CI, 0.873-1.000) in discriminating H3 K27M-mutant gliomas. CONCLUSIONS: The MR imaging characteristics are valuable in discriminating H3 K27M-mutant from wildtype gliomas in the spinal cord and the combination of these imaging features with sex had a high strength in this discrimination.

Total spine MRI for the preoperative evaluation of adolescent idiopathic scoliosis: Part 2 - spinal cord tumors, dysraphisms, diastematomyelia, and vertebral anomalies.

Adolescent idiopathic scoliosis is a commonly encountered condition often diagnosed on screening examination. Underlying, asymptomatic neural axis abnormalities may be present at the time of diagnosis. At certain institutions, total spine MRI is obtained preoperatively to identify these abnormalities. We provide a framework for the radiologist to follow while interpreting these studies. In part 1, we discuss Arnold Chiari malformations, syringomyelia, and the tethered cord. In part 2, we focus on spinal cord tumors, dysraphisms, to include diastematomyelia, and vertebral anomalies.