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The occipital transtentorial approach (OTA) is a very useful but challenging approach to expose the pineal region because the deep-seated arachnoid membranes usually fold and extend over the great vein of Galen (GVG), leading to dense and poor visibility. In addition, the practical aspects of arachnoid anatomy are not well understood. We aimed to develop a safe surgical procedure for the OTA according to the practical aspects of arachnoid anatomy., The procedure is shown through an illustrative video of surgery and cadaver. Five cadavers were analyzed for their arachnoid structures and the surgical procedures via the OTA, in strict compliance with legal and ethical requirements., All cadavers showed a 2-layered arachnoid structure-one belonging to the occipital lobe, and the other to the cerebellum. According to our cadaveric analysis, the arachnoid attachment of the tentorial apex can be peeled bluntly, with an average distance of 10.2 mm. For our clinical presentation, a pineal tumor with hydrocephalus was detected in a 14-year-old boy. While using the OTA and expanding the deep surgical field, we detached the membrane from the tentorial apex and bluntly peeled it to reveal the deep veins. Finally, gross total removal of the tumor was achieved., A 2-layered arachnoid structure interposes the GVG from above and below the tentorium. The arachnoid membrane below the tentorium can be peeled off bluntly from the GVG to the attachment bundle limited by the penetrating veins. This detachment technique is useful for safe enlargement of the surgical field for the OTA.

Most patients with neurogenic thoracic outlet syndrome (NTOS) have a history of trauma. Scar tissue formation within the scalene muscle and around the nerves after injury cause arm and hand symptoms. We report that supraclavicular scalenotomy followed by external neurolysis without rib resection is very effective as the surgical treatment.Consecutive case series. Our aim was to evaluate the outcomes of patients who underwent supraclavicular scalenotomy followed by external neurolysis without rib resection for post-traumatic NTOS. Neurogenic thoracic outlet syndrome (NTOS) comprises over 95% of all TOS patients, and most patients with NTOS have a history of trauma before the onset of their symptoms. Patients treated with supraclavicular scalenotomy and neurolysis without rib resection from September 2014 to December 2019 were retrospectively reviewed by using the medical records and operative notes. Patient's characteristics, clinical symptoms before treatment, operative findings, and short- and long-term outcomes were assessed. To assess clinical outcomes at 2 months after surgery (short-term outcomes) and 12 months later (long-term outcomes), we used a 4-grade categorization (Excellent, Good, Fair, and Poor) of patients’ subjective evaluations after surgery on the basis of modified Odom's criteria. Excellent and Good were defined as a successful outcome. Ninety-six supraclavicular scalenotomies without rib resection were performed on patients with post-traumatic NTOS. The most common intraoperative observation was the fibrous bands within the anterior scalene muscle in 86 cases (89.6%). The short-term outcome with patients’ subjective evaluation in 96 operations at 2 months after surgery showed a 96.9% success rate (Excellent + Good). In 85 cases followed for more than 12 months after surgery, the success rate based on patients’ subjective evaluation at the last clinic follow-up appointment as a long-term outcome was 74.1%. In post-traumatic NTOS, it has been reported the arm and hand symptoms are due to pressure on the brachial plexus, which can stem from the swollen muscle following injuries and later from tightness of the scarred muscle. Considering this mechanism and our results, we concluded that supraclavicular scalenotomy and external neurolysis without rib resection made sense, as they were very effective and adequate to improve symptoms of NTOS. Level of Evidence: 5.

Primary central nervous system lymphoma (PCNSL) is an isolated type of lymphoma of the central nervous system and has a dismal prognosis despite intensive chemotherapy. Recent genomic analyses have identified highly recurrent mutations of MYD88 and CD79B in immunocompetent PCNSL, whereas LMP1 activation is commonly observed in Epstein–Barr virus (EBV)-positive PCNSL. However, a lack of clinically representative preclinical models has hampered our understanding of the pathogenic mechanisms by which genetic aberrations drive PCNSL disease phenotypes. Here, we establish a panel of 12 orthotopic, patient-derived xenograft (PDX) models from both immunocompetent and EBV-positive PCNSL and secondary CNSL biopsy specimens. PDXs faithfully retained their phenotypic, metabolic, and genetic features, with 100% concordance of MYD88 and CD79B mutations present in PCNSL in immunocompetent patients. These models revealed a convergent functional dependency upon a deregulated RelA/p65-hexokinase 2 signaling axis, codriven by either mutated MYD88/CD79B or LMP1 with Pin1 overactivation in immunocompetent PCNSL and EBV-positive PCNSL, respectively. Notably, distinct molecular alterations used by immunocompetent and EBV-positive PCNSL converged to deregulate RelA/p65 expression and to drive glycolysis, which is critical for intracerebral tumor progression and FDG-PET imaging characteristics. Genetic and pharmacologic inhibition of this key signaling axis potently suppressed PCNSL growth in vitro and in vivo. These patient-derived models offer a platform for predicting clinical chemotherapeutics efficacy and provide critical insights into PCNSL pathogenic mechanisms, accelerating therapeutic discovery for this aggressive disease. Significance: A set of clinically relevant CNSL xenografts identifies a hyperactive RelA/p65-hexokinase 2 signaling axis as a driver of progression and potential therapeutic target for treatment and provides a foundational preclinical platform.

OBJECTIVESpinal arteriovenous shunts are rare vascular lesions and are classified into 4 types (types I–IV). Due to rapid advances in neuroimaging, spinal epidural AVFs (edAVFs), which are similar to type I spinal dural AVFs (dAVFs), have recently been increasingly reported. These 2 entities have several important differences that influence the treatment strategy selected. The purposes of the present study were to compare angiographic and clinical differences between edAVFs and dAVFs and to provide treatment strategies for edAVFs based on a multicenter cohort.METHODSA total of 280 consecutive patients with thoracic and lumbosacral spinal dural arteriovenous fistulas (dAVFs) and edAVFs with intradural venous drainage were collected from 19 centers. After angiographic and clinical comparisons, the treatment failure rate by procedure, risk factors for treatment failure, and neurological outcomes were statistically analyzed in edAVF cases.RESULTSFinal diagnoses after an angiographic review included 199 dAVFs and 81 edAVFs. At individual centers, 29 patients (36%) with edAVFs were misdiagnosed with dAVFs. Spinal edAVFs were commonly fed by multiple feeding arteries (54%) shunted into a single or multiple intradural vein(s) (91% and 9%) through a dilated epidural venous plexus. Preoperative modified Rankin Scale (mRS) and Aminoff-Logue gait and micturition grades were worse in patients with edAVFs than in those with dAVFs. Among the microsurgical (n = 42), endovascular (n = 36), and combined (n = 3) treatment groups of edAVFs, the treatment failure rate was significantly higher in the index endovascular treatment group (7.5%, 31%, and 0%, respectively). Endovascular treatment was found to be associated with significantly higher odds of initial treatment failure (OR 5.72, 95% CI 1.45–22.6). In edAVFs, the independent risk factor for treatment failure after microsurgery was the number of intradural draining veins (OR 17.9, 95% CI 1.56–207), while that for treatment failure after the endovascular treatment was the number of feeders (OR 4.11, 95% CI 1.23–13.8). Postoperatively, mRS score and Aminoff-Logue gait and micturition grades significantly improved in edAVFs with a median follow-up of 31 months.CONCLUSIONSSpinal epidural AVFs with intradural venous drainage are a distinct entity and may be classified as type V spinal vascular malformations. Based on the largest multicenter cohort, this study showed that primary microsurgery was superior to endovascular treatment for initial treatment success in patients with spinal edAVFs.

Purpose: Oligodendroglioma has a relatively favorable prognosis, however, often undergoes malignant progression. We hypothesized that preclinical models of oligodendroglioma could facilitate identification of therapeutic targets in progressive oligodendroglioma. We established multiple oligodendroglioma xenografts to determine if the PI3K/AKT/mTOR signaling pathway drives tumor progression. Experimental Design: Two anatomically distinct tumor samples from a patient who developed progressive anaplastic oligodendroglioma (AOD) were collected for orthotopic transplantation in mice. We additionally implanted 13 tumors to investigate the relationship between PI3K/AKT/mTOR pathway alterations and oligodendroglioma xenograft formation. Pharmacologic vulnerabilities were tested in newly developed AOD models in vitro and in vivo. Results: A specimen from the tumor site that subsequently manifested rapid clinical progression contained a PIK3CA mutation E542K, and yielded propagating xenografts that retained the OD/AOD-defining genomic alterations (IDH1R132H and 1p/19q codeletion) and PIK3CAE542K, and displayed characteristic sensitivity to alkylating chemotherapeutic agents. In contrast, a xenograft did not engraft from the region that was clinically stable and had wild-type PIK3CA. In our panel of OD/AOD xenografts, the presence of activating mutations in the PI3K/AKT/mTOR pathway was consistently associated with xenograft establishment (6/6, 100%). OD/AOD that failed to generate xenografts did not have activating PI3K/AKT/mTOR alterations (0/9, P < 0.0001). Importantly, mutant PIK3CA oligodendroglioma xenografts were vulnerable to PI3K/AKT/mTOR pathway inhibitors in vitro and in vivo—evidence that mutant PIK3CA is a tumorigenic driver in oligodendroglioma. Conclusions: Activation of the PI3K/AKT/mTOR pathway is an oncogenic driver and is associated with xenograft formation in oligodendrogliomas. These findings have implications for therapeutic targeting of PI3K/AKT/mTOR pathway activation in progressive oligodendrogliomas.

Study design A systematic review and meta-analysis were performed with the literature including the case of C5 palsy following anterior cervical decompression surgery. Objective The aim of this study was to compare three reconstructive procedures of anterior cervical decompression, the incidences of delayed C5 palsy and other complications were assessed. Summary of background data Delayed C5 palsy is now a well-known complication after cervical decompression surgery. The etiology of C5 palsy has been studied, especially after posterior surgery. However, in anterior surgery there has been a lack of investigation due to procedure variation. Additionally, limited evidence exists regarding the risk of C5 palsy in surgical procedures. Methods We performed an extensive literature search for C5 palsy and other complications with ACDF, ACCF, and their combination (Hybrid). Gross incidences of C5 palsy after these three procedures were compared, and specific superiorities (or inferiorities) were investigated via comparison of binary outcomes between two of three groups using odds ratios (OR). Results Twenty-six studies met the inclusion criteria. A total of 3098 patients were included and 5.8% of those developed C5 palsy. Meta-analyses demonstrated that ACDF had a lower risk of palsy than ACCF (OR 0.36, 95% confidence interval [CI] 0.16-0.78), whereas ACDF versus Hybrid (OR 0.60, 95% CI 0.24-1.51) and Hybrid versus ACCF (OR 1.11, 95% CI 0.29-4.32) were not significantly different. Although these differences were not observed in shorter lesion subgroups, there were significant differences between the three procedures in longer lesion subgroups (P = 0.0005). Meta-analyses revealed that in longer lesions, ACDF had a significantly lower incidence than ACCF (OR 0.42, 95% CI 0.22-0.82). Additionally, Hybrid surgery was noninferior for palsy occurrence compared to ACCF, and suggested a trend for reduced rates of other complications compared to ACCF. Conclusion ACDF may yield better outcomes than Hybrid and ACCF. Furthermore, Hybrid may have advantages over ACCF in terms of surgical complications. Level of evidence 3.

We retrospectively assessed the effectiveness and safety of Gamma Knife radiosurgery (GKRS) for asymptomatic obstructive hydrocephalus associated with posterior fossa metastases, which was known empirically but not well discussed.We reviewed the medical records of 27 patients who underwent GKRS for asymptomatic obstructive hydrocephalus related to posterior fossa metastases.Cumulative control rates of hydrocephalus were 11.1%, 51.9%, 70.4%, and 74.6% at 1, 2, 3, and 6 months after GKRS. Primary gastrointestinal tract cancer (P = 0.001) was significantly correlated with unfavorable management. Evans ratio at GKRS (median 0.31) improved significantly compared with that at 1-3 months after GKRS (median 0.26) (P0.0001) and maintained at 6 to 12 months. Cumulative local tumor control rates were 91.7%, 70.8%, and 64.4% at 3, 6, and 12 months after GKRS. Primary gastrointestinal tract cancer (P = 0.018) and no conventional systemic agents (P = 0.027) were significantly correlated with unfavorable control. Cumulative incidence rates of adverse radiation effects were 0.0%, 16.7%, and 24.2% at 6, 9, and 12 months after GKRS. Primary gastrointestinal tract cancer (P0.0001) and single and 2- or 3-fraction GKRS (P0.0001) were significantly correlated with unfavorable outcomes. All but 1 patient avoided surgical procedure for hydrocephalus after GKRS.The present findings suggest that GKRS is an effective and safe treatment for asymptomatic obstructive hydrocephalus caused by posterior fossa metastases, and all but 1 could avoid invasive surgical procedures for hydrocephalus. Posterior fossa metastases from gastrointestinal tract cancer resulted in unsatisfactory outcomes for control of hydrocephalus, tumor progression, and adverse radiation effects.

Cerebral bypass surgery, such as the superficial temporal artery-middle cerebral artery bypass, is one of the essential procedures for cerebral revascularization. However, very narrow or thin blood vessels will increase the risk of anastomotic problems, such as occurs in Moyamoya disease. For such vessels, we have devised a "lifting method" in the recipient arteriotomy. In the present study, we have introduced this novel optional technique and evaluated its effects.The lifting method is a procedure of lifting the incision edge of a linear incision on the recipient vessel to widen the ostium. We attempted the lifting method in 23 consecutive patients (41 arteries) and, as a historical control, compared the results with those from the conventional method in 25 consecutive patients (37 arteries) for the previous 3 years. We compared patient age, years of surgical experience, recipient vessel diameter, anastomotic events, and final patency. As a subanalysis, the same evaluations were performed separately for patients with Moyamoya disease. Furthermore, the time required for the lifting procedure was measured retrospectively.The incidence of anastomotic events with the conventional method was 13.5% overall and 19% in those with Moyamoya disease. No adverse events occurred with the lifting method (P0.05). No statistically significant differences were found for the other factors, including final patency between the 2 groups. The time required for the lifting procedure averaged 1 minute, 15 seconds.Use of the lifting method widens and secures the ostium in a recipient vessel and greatly facilitates operability. We have found it to be a foolproof method enabling safe and reliable anastomosis even with narrow or thin vessels.

OBJECTIVEThe purpose of the present study was to compare the treatment success rates of primary neurosurgical and endovascular treatments in patients with spinal dural arteriovenous fistulas (dAVFs).METHODSData from 199 consecutive patients with thoracic and lumbosacral spinal dAVFs were collected from 18 centers. Angiographic and clinical findings, the rate of initial treatment failure or recurrence by procedures, risk factors for treatment failure, complications, and neurological outcomes were statistically analyzed.RESULTSSpinal dAVFs were frequently detected in the thoracic region (81%), fed by a single feeder (86%), and shunted into an intradural vein via the dura mater. The fistulous connection between the feeder(s) and intradural vein was located at a single spinal level in 195 patients (98%) and at 2 independent levels in 4 patients (2%). Among the neurosurgical (n = 145), and endovascular (n = 50) treatment groups of single dAVFs (n = 195), the rate of initial treatment failure or recurrence was significantly higher in the index endovascular treatment group (0.68% and 36%). A multivariate analysis identified endovascular treatment as an independent risk factor with significantly higher odds of initial treatment failure or recurrence (OR 69; 95% CI 8.7–546). The rate of complications did not significantly differ between the two treatment groups (4.1% for neurosurgical vs 4.0% for endovascular treatment). With a median follow-up of 26 months, improvements of ≥ 1 point in the modified Rankin Scale (mRS) score and Aminoff-Logue gait and Aminoff-Logue micturition grades were observed in 111 (56%), 121 (61%), and 79 (40%) patients, respectively. Independent risk factors for lack of improvement in the Aminoff-Logue gait grades were multiple treatments due to initial treatment failure or recurrence (OR 3.1) and symptom duration (OR 1.02).CONCLUSIONSBased on data obtained from the largest and most recently assessed multicenter cohort, the present study shows that primary neurosurgery is superior to endovascular treatment for the complete obliteration of spinal dAVFs by a single procedure.

Background Paragangliomas are generally benign, slow-growing tumors. However, approximately 10%–20% are malignant, characterized by distant metastasis. Recently, a germ line mutation in succinate dehydrogenase B subunit (SDHB) has been shown to be associated with malignant behavior in paraganglioma. Here we present a case of SDHB-negative malignant paraganglioma of the jugular foramen with a pseudohypoxic microenvironment and unique imaging features on [18F]-fluoro-2-deoxy- d -glucose positron emission tomography ([18F]-FDG PET), and discuss the significance of SDHB immunohistochemistry and the potential of [18F]-FDG PET for clinical management. Case Description A 55-year-old woman was diagnosed with jugular foramen paraganglioma. Initial surgical resection was performed; however, follow-up [18F]-FDG PET indicated multiple uptake regions throughout the body. Biopsies for multiple recurrent lesions revealed consistent pathological features, suggesting distant metastasis. Immunohistochemical analysis revealed a lack of SDHB immunostaining in all specimens. Pseudohypoxic markers, including hypoxia-inducible factor-1α and downstream glycolysis enzymes, were strongly expressed. [18F]-FDG PET demonstrated increased uptake in the lesions, and the patient died 3 years after initial metastasis. Conclusion In patients with head and neck paraganglioma without SDHB expression, close follow-up should be considered because of the risk for metastasis. In such cases, [18F]-FDG PET might be useful for detecting metastasis due to atypical accumulation from pseudohypoxia-induced glycolysis.

Background Bow hunter's syndrome (BHS) is rare and typically induced by mechanical compression of the dominant vertebral artery (VA) during head rotation. We report a case of BHS induced by nondominant VA compression in which contralateral VA patency was preserved. Definite diagnosis of BHS is not often feasible because of transient symptoms and nonspecific clinical features, such as vertigo or dizziness, especially in nondominant VA compression. We discuss the diagnostic clues of BHS and clinical features of BHS caused by nondominant VA compression through a literature review. Case Description A 65-year-old man suffered repeated bouts of dizziness whenever his head was rotated to the left. This dizziness was consistently accompanied by downbeat nystagmus (DBN). Radiography revealed left VA compression by a lateral osteophyte at the C3-C4 level only during left head rotation. In contrast, patency of the right VA, which was almost equivalent in size to the left VA, was preserved during head rotation. The distinctive clinical finding of head rotation-induced DBN, which is usually associated with lesions involving the caudal midline cerebellum, was observed. Symptoms disappeared immediately after left VA decompression with osteophytectomy and C3-C4 fusion. Conclusions Despite excellent flow through the contralateral VA, occlusion of the nondominant VA occasionally induces BHS. According to a review of the literature, BHS cases do not always depend on the VA on one side for blood supply. Head rotation–induced DBN can be useful for diagnosis of BHS, even in cases of nondominant VA compression.

Primary central nervous system lymphoma (PCNSL) is a rare and aggressive type of extranodal non-Hodgkin lymphoma that carries an unsatisfactory prognosis. Treating refractory PCNSL is challenging because of resistance to conventional cytotoxic and intrathecal chemotherapies. Therefore, novel therapeutic approaches are needed. Here, we report a 12-year-old boy with CD20-positive PCNSL, which was refractory to combination chemotherapy and intravenous rituximab. However, the patient achieved complete remission after repeated intraventricular rituximab administration. The results of this case indicate that intraventricular rituximab is an effective option to treat refractory PCNSL in children.

Study design Basic animal research. Objective The effects of granulocyte colony-stimulating factor (G-CSF) were assessed in a rat chronic spinal cord compression model to explore the potential of G-CSF as a pharmacological treatment for cervical spondylotic myelopathy. Summary of background data G-CSF is a hematopoietic cytokine used clinically to treat neutropenia. Recently, neuroprotective effects of G-CSF have been reported in spinal cord disorders. Methods To introduce the chronic cervical cord compression, thin polyurethane sheets were implanted under C5-C6 laminae of rats and gradually expanded by absorbing water. This model reproduces delayed compressive myelopathy of the cervical spine. In sham operations, the sheets were immediately removed. G-CSF (15 μg/kg) or normal saline (NS) was administered subcutaneously 5 days a week. Experimental groups were sham operation given NS; cord compression given NS; and cord compression given G-CSF. To assess motor functions, rotarod performance, and grip strength were measured. Twenty-six weeks after surgery, cervical spinal cords were examined histopathologically. In the prevention experiment, G-CSF or NS administration was started immediately after surgery. In the treatment experiment, their administration was started 8 weeks after surgery. In another experiment, in three groups in the prevention experiment, terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate-biotin nick end labeling staining was performed to assess apoptotic cell death at 8 weeks after surgery. Results In the prevention experiment, administration of G-CSF preserved the motor functions and motor neurons throughout the 26 weeks, and significantly decreased the number of apoptotic cells at 8 weeks. In the treatment experiment, G-CSF administration from 8 weeks after surgery markedly restored the motor function temporarily to a level equal to the sham group. Conclusion G-CSF prevents the decline in motor functions and preserves motor neurons in the rat chronic cord compression model. G-CSF also improves motor function in the progressive phase of compression myelopathy. Level of evidence N/A.

The suction decompression (SD) method, which proactively aspirates the blood flowing into the aneurysm and reduces the internal pressure of the aneurysm, is useful for clipping surgery of large and giant cerebral aneurysm. However, there has been little discussion on re-utilization of blood aspirated during SD. This study aimed to examine the safety, convenience, and usefulness of autologous transfusion of aspirated blood using a transfusion bag. At the time of craniotomy, the cervical carotid artery is fully exposed. An angiocatheter sheath was inserted into the carotid artery and placed in the internal carotid artery. In SD, blood was aspirated from the sheath at a constant speed and quickly stored in a blood transfusion storage bag. Blood aspiration was repeated with a new syringe; once the transfusion bag was full, the blood was re-administered to the patient. Changes in vital sign and hemoglobin/hematocrit values before and after SD were examined in five cases performed in this procedure. The aspirated blood volumes of five cases ranged from 130 to 400 mL, and all aspirated blood was successfully re-transfused. There was no critical change in vital sign, and no significant decrease in the hemoglobin/hematocrit value. No findings suggestive of complications of thrombus formation, infection, and hemolysis were noted. Re-transfusion of aspirated blood during SD using a transfusion bag is a simple and safe method, which can minimize potential risk of re-utilizing aspirated blood, and enables the safe and easy execution of SD regardless of aspirated blood volume.

OBJECTIVEErythropoietin (EPO) is a clinically available hematopoietic cytokine. The aim of this study was to evaluate the effect of EPO on a rat model of cervical cord compression myelopathy and to explore the possibility of its use as a pharmacological treatment.METHODSTo produce the chronic cervical cord compression model, thin polyurethane sheets were implanted under the C5-C6 laminae of rats and gradually expanded due to water absorption. In this model, motor functions significantly declined from 7 weeks after surgery. Based on the result, EPO administration was started 8 weeks after surgery. Motor function as seen with rotarod performance and grip strength was measured 16 weeks after surgery, and then motor neurons were stained with H-E and NeuN staining, and counted. Apoptotic cell death was assessed with terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate-biotin nick end labeling (TUNEL) staining. To assess transfer of EPO into spinal cord tissue, the EPO level in spinal cord tissue was measured with an enzyme-linked immunosorbent assay for each group after subcutaneous injection of EPO.RESULTSHigh-dose EPO (5000 IU/kg) administered from 8 weeks after surgery markedly restored and maintained motor function in the Compression groups (P < 0.01). EPO significantly prevented loss of motor neurons in the anterior horn (P < 0.05) and significantly decreased the number of TUNEL-positive apoptotic cells (P < 0.05). The EPO level in spinal cord tissue was significantly higher in the High-dose EPO group than other groups.CONCLUSIONSEPO improves motor function in rats with progressive chronic compression myelopathy. EPO protects anterior horn motor neurons and inhibits neuronal cell apoptosis in spinal cord compression. The neuroprotective effects can be produced through transfer of EPO into spinal cord tissue. These findings suggest that EPO has high potential as a treatment for developing compression myelopathy.

INTRODUCTION The utility of surgical simulation with three-dimensional multimodality fusion imaging (3D-MFI) has been demonstrated. However, its potential in deep-seated brain lesions remains unknown. The aim of this study was to investigate the impact of 3D-MFI in deep-seated meningioma operations. MATERIAL AND METHODS Fourteen patients with deeply located meningiomas were included in this study. We constructed 3D-MFIs by fusing high-resolution magnetic resonance (MR) and computed tomography (CT) images with a rotational digital subtraction angiogram (DSA) in all patients. The surgical procedure was simulated by 3D-MFI prior to operation. To assess the impact on neurosurgical education, the objective values of surgical simulation by 3D-MFIs/virtual reality (VR) video were evaluated. To validate the quality of 3D-MFIs, intraoperative findings were compared. The identification rate (IR) and positive predictive value (PPV) for the tumor feeding arteries and involved perforating arteries and veins were also assessed for quality assessment of 3D-MFI. RESULTS After surgical simulation by 3D-MFIs, near-total resection was achieved in 13 of 14 (92.9%) patients without neurological complications. 3D-MFIs significantly contributed to the understanding of surgical anatomy and optimal surgical view (p

Objective Postoperative C5 palsy is a well-known complication after cervical decompression with either a posterior or an anterior approach. Its cause has been discussed more regarding the posterior approach. The main hypothesis is that postoperative spinal cord shift causes root traction and palsy. However, the pathogenesis in anterior cases has not been fully described. Therefore, the purpose of this study was to clarify the risk factors for C5 palsy in the anterior approach through our C5 palsy cases. Methods A total of 149 surgical patients with an anterior cervical lesion were treated by a specific spinal surgeon under consistent same treatment strategy. Of these patients, 88 who satisfied the evaluation criteria were enrolled. Postoperative C5 palsy was defined as postoperative weakness of the deltoid with or without weakness of the biceps brachii. Risk factors of C5 palsy were extracted from clinical backgrounds, surgical approaches, and radiologic findings from patients with palsy. Results Four sides of 3 individuals (4.6%) who underwent multiple corpectomy developed C5 palsy. All paralyses became evident several days after the surgery and recovered. Older age, multiple corpectomy, postoperative spinal cord shift, and foraminal stenosis of C4-5 and C5-6 were statistically extracted as causative factor of C5 palsy. In the patients with palsy, distortion of the anterior nerve root as a result of a residual vertebral spur was observed with anterior spinal cord shift after anterior corpectomy. Conclusions Multiple corpectomy for patients with longer anterior lesions and locally developed kyphosis is related to a larger postoperative cord shift, which can cause the occurrence of C5 palsy. Moreover, C4-5 or C5-6 foraminal stenosis can accelerate tethering of the C5 or C6 nerve root. Older patients undergoing multiple corpectomy are susceptible to these risks of palsy. Appropriate patient selection and sufficient additional foraminotomy should be considered for extensive anterior lesions and locally developed kyphosis to avoid postoperative C5 palsy.

Gorham's disease is a rare disorder of unknown etiology and variable clinical presentation and is characterized by the proliferation of lymphatic vessels associated with massive regional osteolysis. Although 10 cases involving the skull and cervical spine have been reported in the literature, little is available concerning the surgical treatment of either atlantoaxial dislocation or basilar impression. Most cases have experienced universally unsuccessful treatment with bone grafts, which have led to dissolution. This case report describes the clinical course, and radiotherapeutic, medical, and surgical treatment for Gorham's disease with basilar impression and massive osteolysis of the skull and upper cervical spine. The case of a 27-year-old man with progressive massive osteolysis of the skull and cervical spine is reported. Multiple surgical treatments to decompress the spinal cord and stabilize the skull and upper cervical spine with autologous fibular grafts were performed in order to prevent the progression of atlantoaxial dislocation and basilar impression. Pathologically, radiotherapy failed to show any effect. The efficacy of antiresorptive therapy with bisphosphonates could not be confirmed either clinically or radiologically. Although solid bone fusion was not obtained, the patient has achieved a satisfactory functional outcome and remains completely active after repeated surgeries. Surgical treatment is extremely difficult in cases of Gorham's disease involving the skull and upper cervical spine. Fibular bone grafts seem to show resistance to erosion to osteolytic tissue.

Purpose The present study was conducted to assess the diagnostic performance of (18)F-fluoride PET/CT in evaluating hyperostosis and osseous involvement in patients with meningioma. Patients and methods Thirty-four patients with meningioma (mean age, 61 years) underwent (18)F-fluoride PET/CT before surgery. In 24 patients (71%), (18)F-FDG PET/CT was also given before surgery, and the results were compared. The images were reviewed by 2 board-certified nuclear medicine specialists who were unaware of any clinical information and a consensus was reached. Uptake patterns and measurements of tracers were compared with pathological findings from resected specimens, with hyperostosis and osseous involvement as the reference standard. Results There were 27 grade I tumors (79%) and 7 grade II tumors (21%). The primary tumor focus was identified in each patient using both (18)`F-fluoride PET/CT and (18)F-FDG PET/CT, but there were no significant correlations in the degree of uptake between the 2 tracers. The SUV(max), SUV(max) corrected for lean body mass (SUL(max)), and tumor metabolic volume (TMV) for (18)F-fluoride and (18)F-FDG were greater in grade II tumors than in grade I tumors. Hyperostosis and osseous involvement was identified in 12 tumors (38%). The SUV(max), SUL(max), and TMV of tumors visualized with (18)F-fluoride PET/CT were greater in tumors with hyperostosis and osseous involvement than in those without (P = 0.005, P = 0.003, and P = 0.006, respectively). In contrast, the SUV(max), SUL(max), and TMV of tumors visualized with (18)F-FDG PET/CT were similar regardless of hyperostosis or osseous involvement. Conclusions (18)F-fluoride PET/CT may improve detection of hyperostosis and osseous involvement in patients with meningioma.

Clinical and radiological features or characteristics of posterior clinoid process (PCP) meningiomas have rarely been described because of their extreme scarcity and terminological confusion. Therefore, the strategies in the surgical intervention for PCP meningiomas have not been well established. Moreover, the presence of deep and critical neuroanatomical structures and relatively high morbidity, which can be difficult to predict preoperatively, make their surgical excision more challenging. We report two surgical cases of PCP meningioma and discuss the appropriate assessment of preoperative features and surgical strategies with review of the literature. Our study suggests that PCP meningioma may be characterized by the anterior displacement of internal carotid artery, and infero-laterally shifted posterior communicating arteries, and homonymous hemianopsia, a distinctive clinical feature. One of the key issues in PCP meningioma surgery is preservation of the optic nerve. Unlocking the optic nerve by anterior clinoidectomy and dissection, the falciform ligament is the important step to preserve vision for larger tumors. Complication with the perforators is also hazardous of these challenging surgeries than anterior clinoid meningiomas for their specific neuroanatomical structures and might not be feasible to avoid even with additional techniques and critical monitoring. A combination and multi-staged-surgical approach can be options of tailor-made surgical strategy in cases with tumor adhesion to the perforators.

Study design Sham-operation-controlled animal study to assess alterations in blood flow in the spinal cord in a chronic compression model. Laboratory investigation. Objective Cervical myelopathy is a common cause of disability in elderly patients. Hypothesis was made that ischemia subsequent to the spinal cord compression plays an important role in the pathogenesis of the spinal cord dysfunction. This study was undertaken to assess alterations in the blood flow of the spinal cord under chronic compression in a rat model. Summary of background data Histologic study of spinal cord from patients with spondylotic myelopathy showed ischemic tissue changes. Experimentally, spinal cord hypoperfusion in combination with chronic spinal cord compression induced myelopathy in dogs. We previously showed that chronic compression of the spinal cord in rats produces gradual deterioration of mobility of the animals accompanied by cord tissue degeneration compatible with ischemic changes. Methods Chronic compression of the cervical spinal cord was implemented by implantation of a thin urethane polymer sheet under the C5-C6 laminae, which expands by absorbing tissue water over 48-72 hours. The control group underwent sham operation. Twelve weeks later, blood flow to the C3-C4 and C5-C6 spinal cord segments were measured by fluorescent microsphere methods. Results In the control group, the blood flow in the C5-C6 segment was larger than C3-C4 segment. In the compression group, the blood flow in the C5-C6 was significantly reduced compared to the C3-C4 segment. Conclusion Under chronic focal spinal cord compression, there was a decrease of the blood flow in the compressed segment in comparison to the rostral segment. Our data are compatible with the hypothesis that alteration in the spinal cord blood flow contributes to pathogenesis of myelopathy.

Oligodendroglioma (OD) is a subtype of adult diffuse glioma defined by IDH1/2 gene mutation and co-deletion of chromosomal arms 1p and 19q. Although prognosis in OD tumors is initially relatively favorable, the majority of OD develop outgrowth of a subclone that has undergone malignant transformation. Modeling the molecular mechanisms of this tumor progression is crucial to identify therapeutic targets for malignant disease. However, there are few available patient-derived OD xenograft models, which limit preclinical investigations. Here, we present novel patient derived anaplastic oligodendroglioma (AOD) xenograft models. In a panel of OD at different stages of disease, we harvested two distinct cell samples: those with and without PIK3CA mutation. From the tumor that subsequently rapidly progressed and had a PIK3CA mutation, we established a xenograft model that was lethal to the mouse and retained the PIK3CA mutation. In contrast, xenograft did not form from the other tumor that was clinically stable after resection and had wild-type PIK3CA. We confirmed AOD phenotype and the presence of IDH1 mutation and 1p/19q co-deletion in xenograft tissue, indicating successful capture of these signature OD genetic alterations. We also tested to see if PI3K/AKT/mTOR gene mutation could induce patient-derived OD xenograft formation. In our attempts to establish xenograft models, the presence of activating mutations in PI3K/AKT/mTOR pathway was consistently associated with successful xenograft establishment. OD/AOD tumors that did not form xenograft did not have mutation in the PI3K/AKT/mTOR pathway Importantly, we found progressive tumor cells that harbor mutant PIK3CA were vulnerable to alkylating agents and PIK/AKT/mTOR pathway inhibitors. These findings suggest there is a critical role of PI3K/AKT/mTOR pathway activation in driving progression and xenograft formation in oligodendroglial tumors. Our xenograft models will facilitate dissection of the mechanism of malignant transformation, contributing to the identification of optimal therapeutic strategies for patients with oligodendroglial tumors

Background Intracranial mycotic aneurysm (IMA) is a rare neurovascular disease and a well-known complication after infective endocarditis. IMAs potentially carry a high mortality risk resulting from intracranial hemorrhage. Therefore, initial treatment is crucial for IMA patients, but an optimal treatment strategy remains unknown. Herein, we report 1 cases of IMA patients treated with the current usual modalities, and we provide a comprehensive literature review to propose an optimal initial treatment strategy for IMAs. Case Descriptions Case 1: An 80-year-old man received a diagnosis of ruptured IMA. He immediately underwent trapping surgery and was discharged without neurologic deficit. Case 2: A 36-year-old man with previous aortic root replacement received a diagnosis of ruptured IMA. His general condition was considered too unstable to allow him to undergo direct surgery, and the angiographic access route was limited because of the previous aortic replacement surgery. Therefore, we selected conservative therapy; however, the patient subsequently died after complications from a huge intracerebral hemorrhage during medical treatment. Conclusions On the basis of 129 IMA cases across 54 reports published from 2006 to 2016, we propose initial surgical intervention as an optimal treatment for patients with ruptured, and even unruptured, IMAs. Regarding surgical intervention, there was no significant difference in postoperative modified Rankin scale scores between direct surgery and endovascular treatment. By contrast, because antibiotic treatment significantly decreased IMA size in unruptured IMAs, antibiotic treatment might be a reasonable alternative for patients with unruptured IMAs, depending on the patient's situation.

A 65-year-old woman presented with basilar invagination manifesting as neck pain, dysesthesia around the lips, and truncal ataxia. The radiological findings demonstrated invagination of the odontoid process into the medulla oblongata and vertical atlantoaxial subluxation with C1 assimilation. The clivo-axial angle was 88° and the cervicomedullary angle was 115°, indicating severe basilar invagination. We planned occipitocervical fusion with atlantoaxial distraction using a cylindrical titanium cage. C2 pedicle screws were inserted, and the atlantoaxial joint was opened to translocate the odontoid process downward. A cylindrical titanium cage packed with local bone graft was inserted into the opened facet joint space. Occipital-C2 fusion was completed by fastening the occipital bone plates with pedicle screws using titanium rods. Postoperatively, the apex of the odontoid process descended by 7 mm, and the clivo-axial and cervicomedullary angles opened to 112° and 125°, respectively. Invagination of the odontoid process into the medulla oblongata was relieved. The preoperative symptoms improved, and she remained symptom-free without requiring anterior decompression over 2 years. Bone fusion of the atlantoaxial joints was completed with sustained facet distraction 12 months after the surgery, and adequate relief of the basilar invagination was maintained. The atlantoaxial distraction method using a cylindrical titanium cage can be a useful option in posterior fusion surgery for basilar invagination.

Study Design. Basic animal research. Objective. Cervical spondylotic myelopathy is a common condition among elderly and often treated by surgery. To explore possibility of pharmacologic treatment, limaprost alfadex, a prostaglandin E1 derivative with vasodilatory and antiplatelet action, was tried in a rat chronic spinal cord compression model. Summary of Background Data. Limaprost increased the blood flow of cauda equina and improved motor functions in animal models of lumbar stenosis. The drug is clinically used to treat neurogenic intermittent claudication. Methods: Forty-two rats were allocated to four groups: (A) sham operation without permanent cord compression, given 5 mL/kg of distilled water twice a day (n = 6); (B) sham operation, receiving 300 μg/kg limaprost twice a day (n = 6); (C) cord compression, receiving the vehicle (n = 15); and (D) cord compression receiving the drug (n = 15). A thin polyurethane sheet that expands by absorbing water was implanted under the C5―C6 laminae to produce cord compression. For sham operation, the sheet was immediately removed. Exercise tests were repeated on a rotating treadmill until 26 weeks after surgery, and then the animals were killed and the spinal cord harvested for motor neurons counts. Results. Treadmill endurance (seconds, mean ± standard error of mean) 2 weeks after surgery was 497.7 ± 2.3, 434.5 ± 65.5, 423.1 ± 33.0, and 480.5 ± 19.5 in groups A, B, C, and D, respectively. At 26th week, the duration was 497.7 ± 2.3, 421.2 ± 78.8, 21.3 ± 11.7, and 441.3 ± 40.4 (P < 0.0001 for the decrease in C group, multivariate analysis of variance with correction for multiple measures.) The motor neuron counts were 38.3 ± 3.6, 38.2 ± 2.6, 32.6 ± 1.9, and 36.2 ± 2.3 in groups A, B, C, and D (P = 0.34), respectively. Conclusion. Limaprost alfadex prevented decline of forced locomotion capability in rats with chronic compression of the cervical cord.

Object Laminoplasty has been used to expand the cervical spinal canal, based on the belief that reconstruction of the laminae preserves musculoskeletal function. The true efficacy of laminoplasty for maintaining spinal alignment, stability, and flexibility, however, remains to be proven. The authors have developed a new method, myoarchitectonic spinolaminoplasty (MSLP), which preserves all of the nuchal muscles and reconstitutes all of the musculoskeletal couplings to the posterior elements of the vertebrae. The details of this technique are described, and the efficacy of the technique in conserving muscle volume, alignment, and motion, as well as in preventing postoperative musculoskeletal discomfort, is assessed. Methods The authors' previous midline-splitting laminoplasty procedure, which utilized a hydroxyapatite (HA) implant as a substitute for the spinous process, was improved. Detachment of the muscles is avoided with this new technique by cutting inside the spinous process. The bone–muscle flaps are affixed to the HA spinous process. Radiographs, computed tomography scans, and neurological evaluations obtained at the 1-year follow-up in the groups of consecutive patients assessed immediately prior to and after the modification of the previous technique (the control and the MSLP groups, respectively) were analyzed and compared. Results The HA bone constructs became integrated due to osteoconduction. The cross-sectional area of the semispinalis capitis, semispinalis cervicis, and multifidus muscles remained significantly larger in the MSLP group. Slight attenuation in lordosis was observed in the control group, but was prevented in the MSLP group. Range of motion was somewhat restricted in the MSLP group, but the incidence of neck pain and shoulder strain was significantly reduced. Conclusions The new MSLP method was effective in preserving the volume and functions of the nuchal musculature and helping to minimize postoperative musculoskeletal complaints.

The factors associated with hematoma enlargement were analyzed in 24 patients, 16 males and eight females aged 46 to 77 years (mean 58 years), undergoing chronic hemodialysis who were admitted to our hospital with intracerebral hemorrhage between 1994 and 2003. Computed tomography demonstrated hematoma enlargement in eight patients after admission. Age, sex, duration of dialysis, time interval between onset and admission, site of hemorrhage, and blood pressure on admission were not significantly different between patients with and without hematoma enlargement. However, level of consciousness, size and shape of hematoma, prothrombin time, and fibrin degradation product level were significantly different between the two patient groups (p < 0.05). All patients with hematoma enlargement died during the course of treatment. Intracerebral hemorrhage is more difficult to treat in hemodialysis patients than in non-hemodialysis patients, and the outcome is especially poor in patients with large hematoma. The present study suggests that lower level of consciousness, large and irregular hematoma, prolonged prothrombin time, and high fibrin degradation product level are predictors of hematoma enlargement after admission.

A 33-year-old man with an intramedullary spinal cord germinoma was treated successfully with partial resection, combined chemotherapy with carboplatin and etoposide, and reduced-dose local-field radiation therapy. The authors believe this is the first case without syncytiotrophoblastic giant cells so treated. The literature is reviewed, and the appearance, radiologic and histopathologic features, and treatment of germinomas are discussed. © RSNA, 2002

昭和51年11月から, 昭和57年12月までの6年間の転移性皮膚癌20症例を集計した。その原発巣, 転移部位, 臨床像, 組織像, 予後などを検討し, 次のような結果が得られた。1)乳癌が7例でもつとも多いが, すべて女子例で, 男子例に多いのは肺癌であつた。2)転移の出現部位は胸部が多く, とくに原発巣を覆う部位に転移したものが圧倒的に多かつた。3)臨床像は結節型が圧倒的に多く, 4)組織像は腺癌が圧倒的に多かつた。5)皮膚転移後死亡までの平均生存期間は9.4ヵ月で, 1年以内に死亡する例が殆どであつた。