Complications and outcomes of carotid artery stenting in high-risk cases.

OBJECTIVES: Carotid artery stenting is sometimes adapted for some at-risk cases; however, appropriate treatment timing with stroke onset is controversial. This study aims to identify factors that have an impact on complications and outcomes, especially in patients at high risk. MATERIALS AND METHODS: We examined the characteristics of 152 consecutive patients treated by carotid artery stenting between January 2018 and March 2022 and retrospectively analyzed the risk factors for complications and poor outcomes (modified-Rankin-Scale deterioration), such as patient background, carotid artery stenting risks (access route tortuosity, severe calcification, vulnerable plaque, estimated glomerular filtration rate <30 mL/min/1.73 m2, etc.), characteristics of the stenosis, details of treatment, and treatment timing. RESULTS: The average North American Symptomatic Carotid Endarterectomy Trial criteria score was 68.3% and the lesion length was 20.5±9.7mm. Among patients, 107 (70.4%) had a carotid artery stenting risk. In high-risk carotid artery stenting cases, symptomatic complications occurred in 32 (30.0%), and the 90-day modified Rankin scale score deteriorated in 15 cases (14.0%). Multivariate analysis showed that cases with triple antithrombotic therapy (p=0.003), stenting within 7 days (p=0.0032), and after 28+ days (p=0.0035) of stroke onset were independently associated factors for complications. CONCLUSIONS: This study showed that among risk factors, triple antithrombotic therapy in particular was a risk factor for perioperative complications. Carotid artery stenting for patients with stroke after 28 days of onset affects the prognosis. Therefore, although further study is warranted, waiting more than one month for treatment in patients requiring carotid artery stenting is a potential risk.

Moyamoya Syndrome in a Patient with Williams Syndrome: A Case Report.

INTRODUCTION: Moyamoya syndrome associated with Williams syndrome is very rare but has been reported to have severe outcomes. Here, we reported a case of Williams syndrome with moyamoya syndrome that was confirmed by the presence of an RNF213 mutation. CASE PRESENTATION: A 6-year-old boy with Williams syndrome presented with right hemiparesis induced by hyperventilation. Magnetic resonance angiography and cerebral angiography showed severe stenosis of the bilateral internal carotid arteries and development of moyamoya vessels. Genetic analysis identified a heterozygous c.14576G>A (p.R4859K) mutation in RNF213. Moyamoya syndrome was diagnosed, and bilateral indirect revascularization surgery was conducted without complications and with a good postoperative course. In moyamoya syndrome associated with Williams syndrome, adequate perioperative management of both the moyamoya arteries and the cardiovascular abnormalities is important to prevent complications. CONCLUSION: This was the first report on a case in which moyamoya syndrome associated with Williams syndrome was confirmed by the presence of a heterozygous RNF213 mutation. Similar to the workup of moyamoya disease, confirmation of RNF213 mutation in Williams syndrome may be useful in predicting the development of moyamoya syndrome that can lead to severe complications.

Post-stroke administration of omega-3 polyunsaturated fatty acids promotes neurovascular restoration after ischemic stroke in mice: Efficacy declines with aging.

Post-stroke treatment with omega-3 polyunsaturated fatty acids (n-3 PUFAs) may be a promising therapy in young animals but this has not been tested in aged subjects, a population at most risk of ischemic stroke. Herein we examined the therapeutic efficacy of n-3 PUFAs after distal middle cerebral artery occlusion (dMCAO) in young (10-12 weeks old) and aged (18 months old) mice. Post-ischemic mice were randomly assigned to 4 groups that received: 1) regular food with low content of n-3 PUFAs, 2) intraperitoneal docosahexaenoic acid (DHA, a major component of n-3 PUFAs) injections, 3) Fish oil (FO, containing high concentration of n-3 PUFAs) dietary supplement, or 4) combined treatment with DHA and FO dietary supplement. Long-term neurorestoration induced by n-3 PUFA post-stroke administration and its underlying mechanism(s) were analyzed up to 35 days after dMCAO. Aged mice showed more severe neurological deficits than young mice after dMCAO with histological lesions extended to the striatum. Notably, post-stroke treatment with combined DHA injections and FO dietary supplementation was more effective in reducing brain injury and improving sensorimotor function in aged mice than either treatment alone, albeit to a lesser extent than in the young mice. Unlike the improvement in spatial cognitive function observed in young mice, the combined treatment regimen failed to improve cognitive function in aged mice. The reduction in stroke-induced neurological deficits with n-3 PUFA post-treatment was associated with enhanced angiogenesis, oligodendrogenesis, neuron survival and white matter restoration. Together, these results indicate that the neurological benefits of n-3 PUFA administration after stroke extend to older animals and are associated with improved neuronal survival and brain remodeling, therefore suggesting that post-stroke administration of n-3 PUFAs is a viable clinically relevant treatment option against stroke.

Three-dimensional multimodality fusion imaging as an educational and planning tool for deep-seated meningiomas.

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 < .0001) and learning how to preserve critical vessels (p < .0001) and resect tumors safety and extensively (p < .0001) by neurosurgical residents/fellows. The IR of 3D-MFI for tumor-feeding arteries and perforating arteries and veins was 100% and 92.9%, respectively. The PPV of 3D-MFI for tumor-feeding arteries and perforating arteries and veins was 98.8% and 76.5%, respectively. CONCLUSIONS: 3D-MFI contributed to learn skull base meningioma surgery. Also, 3D-MFI provided high quality to identify critical anatomical structures within or adjacent to deep-seated meningiomas. Thus, 3D-MFI is promising educational and surgical planning tool for meningiomas in deep-seated regions.

[Efficacy and Safety of Salvage ESHAP Chemotherapy for Recurrent/Refractory PCNSLs].

BACKGROUND: Primary central nervous system lymphoma(PCNSL)is a primary brain tumor, which appears commonly and occupies around 4.6% of all primary brain tumors. The standard therapy for this tumor is high-dose methotrexate chemotherapy(HD-MTX)and whole-brain irradiation. No salvage therapies for HD-MTX therapy-refractory or recurrent PCNSLs have been standardized. In our institution, ESHAP therapy(high-dose cytarabine:2,000mg, cisplatin:25mg/m2, etoposide:40mg/m2, methylprednisolone:500mg)was administered as a secondary chemotherapy, and the efficiency was examined. METHODS: We administered ESHAP therapy as secondary chemotherapy for patients with refractory/recurrent PCNSL after HD-MTX therapy. Patients with PCNSL who were diagnosed and treated at our institute since 1996 were retrospectively studied. Clinical evaluations were performed based on Karnofsky Performance Status and overall survival, and the effect of ESHAP therapy was evaluated using the Response Assessment in Neuro-Oncology criteria. RESULTS: The number of patients with refractory/recurrent PCNSLs were 18(28-77 years of age, median age of 58.5 years). The response rate(RR)after the first course of salvage ESHAP therapy was 77.8%(14 cases), and complete response(CR)was achieved in 6 cases. The RR after the final course of ESHAP therapy was as high as 61.1%(11 cases), and 4 patients retained CR status. In patients with refractory PCNSL who were treated with HD-MTX, the RR in the final course of salvage ESHAP therapy was as high as 77.8%(7 cases), and 3 patients retained CR status during the periods. The occurrence rate of Grade 3 or higher adverse events, according to the Common Terminology Criteria for Adverse Events version 4.0, was 66.7%(12 cases);all events that were associated with blood and lymphatic system disorders were quickly alleviated, and no fatal adverse events occurred. CONCLUSION: In this study, we retrospectively examined the efficacy of ESHAP therapy as a secondary chemotherapy for patients with refractory/recurrent PCNSL after receiving HD-MTX therapy. Based on our findings, we suggest that ESHAP therapy should be considered as an encouraging secondary chemotherapy for patients with refractory/recurrent PCNSL.

[Intraoperative Artery Wall Stimulating Electromyography during Microvascular Decompression Surgery to Treat Hemifacial Spasm:A Case Report].

OBJECTIVE: Microvascular decompression(MVD)surgery has been established as a standard treatment for hemifacial spasm. However, because decompression surgery results in unfavorable outcomes in some cases, a more critical monitoring strategy is required. To improve surgical outcome for hemifacial spasms, abnormal muscle response(AMR)has been proposed as a tool for intraoperative electrophysiological monitoring during MVD surgery. Here, we report a single case of surgical MVD monitoring using artery wall stimulating electromyography(AWS-EMG). AWS-EMG was developed as a new monitoring method in addition to AMR. CASE DESCRIPTION: A 60-year-old woman was diagnosed with hemifacial spasm using magnetic resonance imaging and magnetic resonance angiography fusion imaging. We performed MVD surgery using AWS-EMG and AMR. We successfully identified AWS-EMG before decompression and confirmed immediate AWS-EMG loss after decompression. This behavior was consistent with AMR. After surgery, the patient showed no further symptoms of hemifacial spasm. CONCLUSIONS: In addition to AMR, AWS-EMG might be a promising candidate for intraoperative monitoring for patients with hemifacial spasm.

Occipitocervical fusion with relief of odontoid invagination: atlantoaxial distraction method using cylindrical titanium cage for basilar invagination--case report.

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.

Differences and Advantages of Particles versus Liquid Material for Preoperative Intracranial Tumor Embolization: A Retrospective Multicenter Study.

Objectives: The superiority and usefulness of liquid material over particles for embolization have been a topic of debate due to differences in materials and techniques. This study aimed to identify the complications and outcomes associated with both embolization materials. Methods: This retrospective multicenter cohort study included 93 patients from an endovascular treatment registry, treated from January 1, 2018 to May 31, 2022. It included patients who underwent preoperative embolization for meningioma, solitary fibrous tumor/hemangiopericytoma, and hemangioblastoma. Data for patient characteristics, procedural factors, complications, and outcomes were collected from medical records. Results: A tortuous access route was the only factor independently associated with complications (p = 0.020). Although liquid material was more frequently used for embolization in relatively high-risk conditions, complication rates did not differ significantly between the groups (p = 0.999). In the liquid material group, the tip of the microcatheter could be guided closer to the tumor (p <0.001) using a distal access catheter and flow-guide microcatheters. The subgroup middle meningeal artery embolization had less operative bleeding in the liquid material group (p <0.001), whereas the particles group exhibited less intraoperative blood loss than the liquid material group (p = 0.006). Conclusion: The vascular tortuosity of the access route was only associated with complications in preoperative tumor embolization. Liquid material and particles showed no difference in complication rates. The use of particles in embolization may reduce intraoperative bleeding, but not in all cases can it be used safely. Therefore, a thorough understanding of the characteristics of both approaches and their relative advantages in clinical practice is essential to opt for the appropriate material according to the case.

Intraoperative Integrated Diagnostic System for Malignant Central Nervous System Tumors.

PURPOSE: The 2021 World Health Organization (WHO) classification of central nervous system (CNS) tumors uses an integrated approach involving histopathology and molecular profiling. Because majority of adult malignant brain tumors are gliomas and primary CNS lymphomas (PCNSL), rapid differentiation of these diseases is required for therapeutic decisions. In addition, diffuse gliomas require molecular information on single-nucleotide variants (SNV), such as IDH1/2. Here, we report an intraoperative integrated diagnostic (i-ID) system to classify CNS malignant tumors, which updates legacy frozen-section (FS) diagnosis through incorporation of a qPCR-based genotyping assay. EXPERIMENTAL DESIGN: FS evaluation, including GFAP and CD20 rapid IHC, was performed on adult malignant CNS tumors. PCNSL was diagnosed through positive CD20 and negative GFAP immunostaining. For suspected glioma, genotyping for IDH1/2, TERT SNV, and CDKN2A copy-number alteration was routinely performed, whereas H3F3A and BRAF SNV were assessed for selected cases. i-ID was determined on the basis of the 2021 WHO classification and compared with the permanent integrated diagnosis (p-ID) to assess its reliability. RESULTS: After retrospectively analyzing 153 cases, 101 cases were prospectively examined using the i-ID system. Assessment of IDH1/2, TERT, H3F3AK27M, BRAFV600E, and CDKN2A alterations with i-ID and permanent genomic analysis was concordant in 100%, 100%, 100%, 100%, and 96.4%, respectively. Combination with FS and intraoperative genotyping assay improved diagnostic accuracy in gliomas. Overall, i-ID matched with p-ID in 80/82 (97.6%) patients with glioma and 18/19 (94.7%) with PCNSL. CONCLUSIONS: The i-ID system provides reliable integrated diagnosis of adult malignant CNS tumors.

The interaction of Kinesin-1 with its adaptor protein JIP1 can be regulated via proteins binding to the JIP1-PTB domain.

BACKGROUND: The regulatory mechanisms of motor protein-dependent intracellular transport are still not fully understood. The kinesin-1-binding protein, JIP1, can function as an adaptor protein that links kinesin-1 and other JIP1-binding "cargo" proteins. However, it is unknown whether these "cargo" proteins influence the JIP1-kinesin-1 binding. RESULTS: We show here that JIP1-kinesin-1 binding in Neuro2a cells was dependent on conserved amino acid residues in the JIP1-phosphotyrosine binding (PTB) domain, including F687. In addition, mutation of F687 severely affected the neurite tip localization of JIP1. Proteomic analysis revealed another kinesin-1 binding protein, JIP3, as a major JIP1 binding protein. The association between JIP1 and JIP3 was dependent on the F687 residue in JIP1, and this association induced the formation of a stable ternary complex with kinesin-1. On the other hand, the binding of JIP1 and JIP3 was independent of kinesin-1 binding. We also show that other PTB binding proteins can interrupt the formation of the ternary complex. CONCLUSIONS: The formation of the JIP1-kinesin-1 complex depends on the protein binding-status of the JIP1 PTB domain. This may imply a regulatory mechanism of kinesin-1-dependent intracellular transport.

De novo progressive dural arteriovenous fistula with putamen hemorrhage associated with long-term Down syndrome: A case report and literature review.

Dural arteriovenous fistula (DAVF) is considered an acquired change in blood flow related to factors such as craniotomy, trauma, and infection. However, several factors related to its development remain unknown. Here, we present a case of a 48-year-old man with Down syndrome and Eisenmenger syndrome. He had a history of craniotomy for multiple brain abscesses, followed by the occurrence of a de novo straight sinus (StS) DAVF within the last 2 years. The patient presented with right putamen hemorrhage due to venous congestion by a StS DAVF. The shunt flow was occluded by transarterial embolization using Onyx. Several studies have reported on DAVF models induced by venous congestion and hypoxemia. In this case, local venous congestion due to craniotomy for multiple brain abscesses was considered as one of the causes of DAVF. Complication of venous thrombosis or chronic hypoxemia due to Eisenmenger syndrome might have led to its progression. Especially in DAVF cases with Down syndrome, concomitant symptoms such as hypoxemia due to congenital heart failure and coagulopathy could worsen the disease state progressively.

Biphenotypic Sinonasal Sarcoma: A Genetically Confirmed Case Showing Bone Invasion Accompanying a Non-neoplastic Respiratory Epithelium.

Biphenotypic sinonasal sarcoma is a newly established tumor entity that is associated with distinct clinicopathological findings. Biphenotypic sinonasal sarcoma is a rare, low-grade spindle cell sarcoma that arises in middle-aged females, exclusively in the sinonasal tract. A fusion gene involving PAX3 is detected in most biphenotypic sinonasal sarcomas, which aids in its diagnosis. Here, we report a case of biphenotypic sinonasal sarcoma with its cytological findings. The patient was a 73-year-old woman who presented with purulent nasal discharge and dull pain in the left cheek area. Computed tomography showed a mass extending from the left nasal cavity to the left ethmoid sinus, the left frontal sinus, and the frontal skull base. She underwent a combined transcranial and endoscopic approach for en bloc resection with a safety margin. Histologically, spindle-shaped tumor cells have been thought to proliferate mainly in the subepithelial stroma. Here, nasal mucosal epithelial hyperplasia was noted, and the tumor had invaded the bone tissue accompanying the epithelial cells. Fluorescence in situ hybridization (FISH) analysis showed a PAX3 rearrangement, and next-generation sequencing identified a PAX3::MAML3 fusion. Based on FISH, split signals were observed not in respiratory cells but in stromal cells. This indicated that respiratory cells were non-neoplastic. In the diagnosis of biphenotypic sinonasal sarcoma, the inverted growth of the respiratory epithelium can be a diagnostic pitfall. FISH analysis using a PAX3 break-apart probe is helpful not only for an accurate diagnosis but also for detecting the true neoplastic cells.

Magnetic Resonance Imaging Scan of the Brain After Mild COVID-19 Infection.

PURPOSE: There have been several reports of central nervous system impairments associated with severe coronavirus disease 2019 (COVID-19) infection on head magnetic resonance imaging and angiography (MRI/A). However, head MRI/A is rarely performed in mild cases, and there have been few reports on intracranial changes after COVID-19 infection in these cases. Here, we report a comparative examination of the findings seen in common head MRI/A sequences in mild cases of COVID-19. METHODS: Of the 15,376 patients who underwent head MRI/A examination called "Brain Dock" between June 2020 and June 2021, 746 patients who received a COVID-19 antibody test were evaluated. Positive and negative patients were comparatively examined for head MRI/A findings such as cerebral white matter lesions, ischemic changes, cerebral microbleeds, cerebral aneurysms, arterial stenosis, sinusitis, and other abnormal findings. RESULTS: Overall, 31 (4.2%) patients were COVID-19 positive, and all of them had mild infections not requiring hospitalization. There was no significant difference in patient characteristics and head MRI/A findings between positive and negative patients. All positive patients showed no particular abnormalities in the nasal findings such as olfactory bulb atrophy or thickening of the olfactory mucosa. CONCLUSION: Intracranial lesions in mild patients do not show a clear difference from those in negative patients. This indicates that findings seen in common MRI/A sequences of severe patients are not likely in mild patients, supporting that there is relatively no damage to the central nervous system in mild patients.

Arteries Around the Superior Limiting Sulcus: Motor Complication Avoidance in Insular and Insulo-Opercular Surgery.

BACKGROUND AND OBJECTIVES: Insulo-opercular surgery can cause ischemic motor complications. A source of this is the arteries around the superior limiting sulcus (SLS), which reach the corona radiata, but the detailed anatomy remains unclear. To characterize arteries around the SLS including the long insular arteries (LIAs) and long medullary arteries, we classified them and examined their distribution in relation to the SLS, which helps reduce the risk of ischemia. METHODS: Twenty adult cadaveric hemispheres were studied. Coronal brain slices were created perpendicular to the SLS representing insular gyri (anterior short, middle short, posterior short, anterior long, and posterior long). The arteries within 10-mm proximity of the SLS that reached the corona radiata were excavated and classified by the entry point. RESULTS: A total of 122 arteries were identified. Sixty-three (52%), 20 (16%), and 39 (32%) arteries penetrated the insula (LIAs), peak of the SLS, and operculum (long medullary arteries), respectively. 100 and six (87%) arteries penetrated within 5 mm of the peak of the SLS. The arteries were distributed in the anterior short gyrus (19%), middle short gyrus (17%), posterior short gyrus (20%), anterior long gyrus (19%), and posterior long gyrus (25%). Seven arteries (5.7%) had anastomoses after they penetrated the parenchyma. CONCLUSION: Approximately 90% of the arteries that entered the parenchyma and reached the corona radiata were within a 5-mm radius of the SLS in both the insula and operculum side. This suggests that using the SLS as a landmark during insulo-opercular surgery can decrease the chance of ischemia.

Transvenous embolization for an intraosseous clival arteriovenous fistula via a proper access route guiding a three-dimensional fusion image: illustrative case.

BACKGROUND: Intraosseous clival arteriovenous fistulas (AVFs), in which the shunt drains extracranially from the posterior and anterior condylar veins rather than from the cavernous sinus (CS), are rare. Targeting embolization of an intraosseous clival AVF is challenging because of its complex venous and skull base anatomy; therefore, a therapeutic strategy based on detailed preoperative radiological findings is required to achieve a favorable outcome. Here, the authors report the successful targeted embolization of an intraosseous clival AVF using an ingenious access route. OBSERVATIONS: A 74-year-old woman presented with left-sided visual impairment, oculomotor nerve palsy, and right facial pain. A fusion image of three-dimensional rotational angiography and cone-beam computed tomography revealed a left CS dural AVF and a right intraosseous clival AVF. The shunt flow of the clival AVF drained extracranially from the posterior and anterior condylar veins via the intraosseous venous route. Transvenous embolization was performed by devising suboccipital, posterior condylar, and intraosseous access routes. The symptoms resolved after the bilateral AVFs were treated. LESSONS: Accurate diagnosis and proper transvenous access based on detailed intraosseous and craniocervical venous information obtained from advanced imaging modalities are key to resolving intraosseous clival AVF.

"The microcatheter contrast injection technique": A novel technique to detect the proximal end of a thrombus in mechanical thrombectomy.

Background: An aspiration catheter needs to attach to a thrombus in order to achieve first-pass recanalization by mechanical thrombectomy (MT) for acute ischemic stroke (AIS), particularly that using a direct aspiration first pass technique. The meniscus sign, which is defined as meniscoid contrast opacification indicating the proximal edge of a thrombus, has been suggested to contribute to successful recanalization. In some cases, the meniscus sign is not detected following an injection of contrast medium through a guiding catheter. To precisely identify the location of a thrombus, we use "the microcatheter contrast injection (MCI) technique," which accurately shows the proximal edge of a thrombus. We herein introduce this novel technique and discuss its efficacy in MT. Methods: In cases without the meniscus sign, a microcatheter was advanced to the distal end of contrast opacification, and contrast medium was injected through the microcatheter to detect the meniscus sign. An aspiration catheter was then advanced to the thrombus indicated by the meniscus sign and slowly withdrawn under aspiration. Results: 29 patients underwent MT for AIS using the MCI technique. Even in cases without the meniscus sign on initial angiography, the MCI technique accurately revealed the proximal edge of the thrombus. Moreover, middle cerebral artery occlusion due to atherosclerotic stenosis and displacement of the aspiration catheter and thrombus axis were detected using this technique. Conclusions: The MCI technique may effectively reveal the exact site of a thrombus and increase the success rate of first-pass recanalization.

Availability of tracheal shift in the chest X-ray image as pre-treatment evaluation of mechanical thrombectomy.

BACKGROUND: The use of mechanical thrombectomy (MT) for treatment of acute large vessel occlusion has recently increased. Prompt and timely guiding catheter (GC) induction is necessary to improve prognosis of MT and reduce the time for recanalization. However, difficulties in GC induction are encountered in some patients. This GC induction depends mainly on the aortic arch structure. Therefore, this study focused on assessing presence of tracheal shift on chest X-ray images as pre-treatment evaluation method for GC induction due to its wide availability as an indicator for status of the mediastinum. METHODS: We retrospectively examined 33 patients who underwent MT at our facilities between April 2017 and March 2021. The patients were divided into two groups according to presence or absence of tracheal shift on chest X-ray images. Background characteristics and treatment courses in these two groups were compared. RESULTS: Among 33 patients, tracheal shift was observed on the chest X-ray images of 14 patients. Furthermore, tracheal shift was positively correlated with the time of GC induction (32.9 min vs. 11.6 min, [p < 0.05]) and the female sex (p = 0.03). Additionally, tracheal shift exhibited correlations with multiple risk factors of atherosclerosis (p = 0.04). CONCLUSIONS: In patients with tracheal shift, GC induction could be expectedly difficult. Therefore, advanced disinfection of the right upper arm and affected side of the neck during MT in preparation for changing an approach route is required.

Reconstructive embolization for contralateral vertebral artery dissecting aneurysm that developed after internal trapping of ruptured vertebral artery dissection: A case report and literature review.

Background: It is not well-known that contralateral vertebral artery dissecting aneurysms (VADA) may be newly revealed after parental artery occlusion for unilateral VADA. However, the optimal treatment strategies and perioperative management have not been established. In this report, we present the case of a patient who required reconstructive embolization in the subacute stage for contralateral VADA developed after endovascular internal trapping of the ruptured VADA. Case Description: A 61-year-old man developed subsequent disturbance of consciousness. Head CT showed a diffuse and symmetrical SAH. 3DCT revealed a fusiform aneurysm of the left intracranial vertebral artery with bleb formation. We performed emergency endovascular parent artery occlusion of the left vertebral artery. A digital subtraction angiography on postoperative day 16 showed continued occlusion of the left VA, and a fusiform aneurysm was noted at the right VA. We performed reconstructive embolization and the patient eventually recovered with minimal persistent symptoms. Conclusion: Since the outcomes of contralateral VAD complicated by infarction or hemorrhage are poor, and most cases develop within 7-14 days after endovascular internal trapping for unilateral VAD, performing bilateral radiographic reinspection within this time frame is recommended for early detection and preventive treatment of possible contralateral VADs.

Surgical treatment for late complications following gamma knife surgery for arteriovenous malformations.

BACKGROUND: To establish the surgical indications and strategy for late complications following gamma knife surgery (GKS) for arteriovenous malformations (AVMs). METHODS: Ten male and 7 female patients aged 17-52 years (mean 28.0 years) were retrospectively identified among 686 patients who underwent GKS for AVM at our hospital. Ten patients showed cyst formation (group A), 2 patients had expanding hematoma (group B), and 5 patients had both cyst and expanding hematoma (group C). RESULTS: The mean nidus volume was 10.1 ml (range 0.1-36 ml), and the mean prescription dose at the nidus margin was 19.9 Gy (range 18-28 Gy). Complete obliteration of the nidus was obtained in 12 patients, partial obliteration in 4, and no change in 1. Cyst formation (group A) was asymptomatic in 5 patients, and symptomatic in 5 patients, manifesting as headache, hemianopia, aphasia, and motor weakness. Expanding hematoma (groups B and C) was associated with surrounding brain edema and was symptomatic in all 7 patients. Cyst opening in 1 patient and placement of an Ommaya reservoir in 2 patients were necessary in group A. Both patients in group B underwent craniotomy. Four of the 5 patients in group C required craniotomy. Another patient in group C was lost to follow-up and the final outcome was unknown. CONCLUSIONS: Cyst formation is one of the late complications of GKS for AVM. Some cysts show spontaneous regression but others gradually increase in size and become symptomatic, although relatively large asymptomatic cysts are also known. Predicting the future course of a cyst is difficult. Surgery such as placement of an Ommaya reservoir should be considered for symptomatic cases. Expanding hematoma always increases in size and becomes symptomatic, so removal by craniotomy is necessary. Surrounding brain edema decreases rapidly after surgery and neurological symptoms quickly resolve.

Practical Arachnoid Anatomy for the Technical Consideration of Galen Complex Dissection: Cadaveric and Clinical Evaluation.

BACKGROUND: 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. METHODS: 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. RESULTS: 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. CONCLUSIONS: 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.