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OBJECTIVE Carotid stenosis can lead to both cognitive impairment (CI) and ischemic stroke. Although carotid revascularization surgery, which includes carotid endarterectomy (CEA) and carotid artery stenting (CAS), can prevent future strokes, its effect on cognitive function is controversial. In this study, the authors examined resting-state functional connectivity (FC) in carotid stenosis patients with CI undergoing revascularization surgery, with a particular focus on the default mode network (DMN). METHODS Twenty-seven patients with carotid stenosis who were scheduled to undergo CEA or CAS between April 2016 and December 2020 were prospectively enrolled. A cognitive assessment, including the Mini-Mental State Examination (MMSE), Frontal Assessment Battery (FAB), and Japanese version of the Montreal Cognitive Assessment (MoCA), as well as resting-state functional MRI, was performed 1 week preoperatively and 3 months postoperatively. For FC analysis, a seed was placed in the region associated with the DMN. The patients were divided into two groups according to the preoperative MoCA score: a normal cognition (NC) group (MoCA score ≥ 26) and a CI group (MoCA score < 26). The difference in cognitive function and FC between the NC and CI groups was investigated first, and then the change in cognitive function and FC after carotid revascularization was investigated in the CI group. RESULTS There were 11 and 16 patients in the NC and CI groups, respectively. The FC of the medial prefrontal cortex with the precuneus and that of the left lateral parietal cortex (LLP) with the right cerebellum were significantly lower in the CI group than in the NC group. In the CI group, significant improvements were found in MMSE (25.3 vs 26.8, p = 0.02), FAB (14.4 vs 15.6, p = 0.01), and MoCA scores (20.1 vs 23.9, p = 0.0001) after revascularization surgery. Significantly increased FC of the LLP with the right intracalcarine cortex, right lingual gyrus, and precuneus was observed after carotid revascularization. In addition, there was a significant positive correlation between the increased FC of the LLP with the precuneus and improvement in the MoCA score after carotid revascularization. CONCLUSIONS These findings suggest that carotid revascularization, including CEA and CAS, might improve cognitive function based on brain FC in the DMN in carotid stenosis patients with CI.

Background: Some reports have described intraosseous arteriovenous fistulas showing osteolytic changes, but an osseous arteriovenous fistula (AVF) at the jugular bulb showing extensive bone destruction is a very rare disease. Case description: A 60-year-old man presented with pulsatile tinnitus and right facial nerve palsy. Radiological imaging showed a large homogenously enhanced osteolytic lesion at the right jugular foramen. A cerebral angiogram showed a high-flow vascular lesion of the jugular bulb associated with retrograde sinus reflux, resulting in venous congestion of the deep venous system. These findings led us to misdiagnose this lesion as a glomus jugular tumor. However, combined arterial and venous angiography after transarterial embolization revealed the precise angioarchitecture, and we finally diagnosed this lesion as a high-flow osseous AVF at the jugular bulb. We performed transvenous embolization using a triple catheter technique. The lesion was successfully obliterated, and the 6-months angiogram showed no recurrence. Conclusion: A rare case of high flow osseous AVF at the jugular bulb associated with osteolytic changes in the surrounding bony structure is reported. Although many hypervascular lesions at the jugular bulb are glomus tumors, bone destructive osseous AVF at the jugular bulb should be considered.

OBJECTIVE Preservation of neurological function is a priority when performing a resection of a vestibular schwannoma (VS). Few studies have examined the radiographic value of a fundal fluid cap—i.e., cerebrospinal fluid in the lateral end of a VS within the internal auditory canal—for prediction of postoperative neurological function. The aim of this study was to clarify whether the presence of a fundal fluid cap on preoperative magnetic resonance images has a clinical impact on facial nerve function after resection of VSs. METHODS The presence of a fundal fluid cap and its prognostic impact on long-term postoperative facial nerve function were analyzed. RESULTS A fundal fluid cap was present in 102 of 143 patients who underwent resection of sporadic VSs via the retrosigmoid approach. Facial nerve function was acceptable (House-Brackmann grade I–II) immediately after surgery in 82 (80.4%) patients with a fundal fluid cap and in 26 (63.4%) of those without this sign. The preservation rate of facial nerve function increased in a time-dependent manner after surgery in patients with a fundal fluid cap but plateaued by 3 months postoperatively in those without a fundal fluid cap; the difference was statistically significant at 12 months (96.1% vs 82.9%, p = 0.013) and 24 months (97.1% vs 82.9%, p = 0.006) after surgery. The presence of a fundal fluid cap had a significantly positive effect on long-term facial nerve function at 24 months after surgery when tumor size and intraoperative neuromonitoring response were taken into account (OR 5.55, 95% CI 1.12–27.5, p = 0.034). CONCLUSIONS Neuromonitoring-guided microsurgery for total resection of VSs is more likely to be successful in terms of preservation of facial nerve function if a fundal fluid cap is present. This preoperative radiographic sign could be helpful when counseling patients and deciding the treatment strategy.

Symptomatic vasospasm (SVS) is a major cause of morbidity and mortality in aneurysmal subarachnoid hemorrhage (SAH), and serum sodium frequently decreases before SVS. Serum sodium changes might be regulated by sodium metabolism-related hormones. This multi-institutional prospective cohort study therefore investigated the measurement of sodium metabolism-related hormones to elucidate the pathophysiology of serum sodium changes in SAH.SAH patients were treated with clipping or coiling from September 2017 to August 2020 at five hospitals. The laboratory data of 133 SAH patients were collected over 14 days and correlations between changes in serum sodium, sodium metabolism-related hormones (plasma adrenocorticotropic hormone (ACTH), serum cortisol, plasma arginine vasopressin (AVP)), and SVS were determined. Serum sodium concentrations were measured every day and serum sodium levels135 mEq/L were maintained until day 14.Of the 133 patients, 18 developed SVS within 14 days of subarachnoid hemorrhage onset (SVS group) and 115 did not suffer from SVS (non-SVS group). Circulating AVP, ACTH, and cortisol concentrations were significantly higher on day 1 in the SVS group compared with the non-SVS group. Fluctuations in serum sodium in the SVS group were significantly higher than those in the non-SVS group. There were antiparallel fluctuations in serum sodium and potassium from days 2 to 14.Elevated levels of ACTH/cortisol and AVP on day 1 may be predictive markers for the occurrence of SVS. Multiple logistic regression analysis showed that serum sodium fluctuations were associated with SVS occurrence. Serum sodium fluctuations were associated with stress-related hormonal dynamics. (249 words).

The objective of this study was to evaluate our 12-year experience in treating Borden type III transverse-sigmoid sinus (TSS) dural arteriovenous fistulas (DAVFs) and discuss the technical aspects of ipsilateral and contralateral transvenous embolization (TVE) approaches.We retrospectively reviewed charts of consecutive patients with TSS DAVF treated with multimodal treatment between April 2008 and March 2020. The baseline patient characteristics, imaging data, details of procedure, data sets of sinus pressure monitoring, and clinical results were systematically collected.Of 44 patients with TSS DAVF who were treated during study periods, 23 patients of Borden type III were extracted. Among the 23 patients, 18 with transfemoral TVE were included for analysis. TVE was performed using an ipsilateral approach in 8 patients and a contralateral approach in 10. Pressure monitoring data revealed that initial mean sinus pressure (43.5 mmHg vs. 29.5 mmHg; P = 0.033), maximum sinus pressure during the procedure (69.0 mmHg vs. 40.5 mmHg; P = 0.011), and sinus pressure gradient (22.5 mmHg vs. 5.5 mmHg; P = 0.021) were significantly higher in the ipsilateral approach group. The complete obliteration rate by primary embolization was 94% in our cohort with the recurrence rate of 5.6% with a median follow-up period of 57 months.Our study showed the durability of TVE for patients with Borden type III TSS DAVF. TVE performed via the contralateral approach might prevent a potentially dangerous increase in intraprocedural sinus pressure and cortical venous reflux.

BACKGROUND: The thin-walled regions (TIWRs) of intracranial aneurysms have a high risk of rupture during surgical manipulation. They have been reported to be predicted by wall shear stress and pressure (PS) based on computational fluid dynamics analysis, although this remains controversial. In this study, we investigated whether the oscillatory shear index (OSI) can predict TIWRs. METHODS: Twenty-five unruptured aneurysms were retrospectively analyzed; the position and orientation of the computational fluid dynamics color maps were adjusted to match the intraoperative micrographs. The red area on the aneurysm wall was defined as TIWR, and if most of the regions on the color map corresponding to TIWR were OSI low (lower quartile range), time-averaged wall shear stress (TAWSS) high, or PS high (upper quartile range), each region was defined as a matched region and divided by the total number of TIWRs to calculate the match rate. In addition, the mean values of OSI, TAWSS, and PS corresponding to TIWRs were quantitatively compared with those in adjacent thick-walled regions. RESULTS: Among 27 TIWRs of 25 aneurysms, 23, 10, and 14 regions had low OSI, high TAWSS, and high PS regions (match rate: 85.2%, 37.0%, and 51.9%), respectively. Receiver operating characteristic curve analysis demonstrated that OSI was the most effective hemodynamic parameter (area under the curve, 0.881), followed by TAWSS (0.798). Multivariate analysis showed that OSI was a significant independent predictor of TIWRs (odds ratio, 18.30 [95% CI, 3.2800e102.00], P < 0.001). CONCLUSIONS: OSI may be a unique predictor for TIWRs. Low OSI strongly corresponds with TIWRs of intracranial aneurysms.

Intracranial vessel dissection is a procedural complication associated with endovascular treatment. However, there have been few reports on its potential causes and management during mechanical thrombectomy. In approximately 250 cases of mechanical thrombectomy over the past 5 years at our institution, iatrogenic intracranial dissection occurred in 2 patients (0.8%). In this report, we described these 2 cases that were rescued through emergent stenting. Mechanical thrombectomy, using both a stent retriever and an aspiration catheter, was performed for acute middle cerebral artery M2 occlusion in Patient 1 (a 69-year-old man) and for distal M1 occlusion in Patient 2 (an 83-year-old woman). In both cases, recanalization was achieved with the procedure, but irregular stenosis developed at the initially nonoccluded, but mildly arteriosclerotic, M1, after recanalization. During the thrombectomy procedure, the aspiration catheter sifted up to the arteriosclerotic M1. In both cases, the lesions were considered vessel dissection, due to a shift of the aspiration catheter tip into the arteriosclerotic vessel wall. Repeated percutaneous angiography with antithrombotic therapy failed to improve the lesions and to maintain the antegrade blood flow. Finally, lesions in each patient were successfully rescued through the use of emergent stenting. A drug-eluting stent for coronary use was deployed in Patient 1, and an Enterprise stent was applied in Patient 2. Inadvertent shift of the aspiration catheter into arteriosclerotic vessels can cause a serious intracranial vessel dissection. When performing mechanical thrombectomy, intracranial stents need to be available as rescue treatment devices to manage refractory iatrogenic intracranial vessel dissection.

Background We previously reported that heat shock protein 27 (HSP27) phosphorylation plays an important role in the activation of glucose-6-phosphate dehydrogenase (G6PD), resulting in the upregulation of the pentose phosphate pathway and antioxidant effects against cerebral ischemia–reperfusion injury. The present study investigated the effect of geranylgeranylacetone, an inducer of HSP27, on ischemia–reperfusion injury in male rats as a preliminary study to see if further research of the effects of geranylgeranylacetone on the ischemic stroke was warranted. Methods In all experiments, male Wistar rats were used. First, we conducted pathway activity profiling based on a gas chromatography–mass spectrometry to identify ischemia–reperfusion-related metabolic pathways. Next, we investigated the effects of geranylgeranylacetone on the pentose phosphate pathway and ischemia–reperfusion injury by real-time polymerase chain reaction (RT-PCR), immunoblotting, and G6PD activity, protein carbonylation and infarct volume analysis. Geranylgeranylacetone or vehicle was injected intracerebroventricularly 3 h prior to middle cerebral artery occlusion or sham operation. Results Pathway activity profiling demonstrated that changes in the metabolic state depended on reperfusion time and that the pentose phosphate pathway and taurine-hypotaurine metabolism pathway were the most strongly related to reperfusion among 137 metabolic pathways. RT-PCR demonstrated that geranylgeranylacetone did not significantly affect the increase in HSP27 transcript levels after ischemia–reperfusion. Immunoblotting showed that geranylgeranylacetone did not significantly affect the elevation of HSP27 protein levels. However, geranylgeranylacetone significantly increase the elevation of phosphorylation of HSP27 after ischemia–reperfusion. In addition, geranylgeranylacetone significantly affected the increase in G6PD activity, and reduced the increase in protein carbonylation after ischemia–reperfusion. Accordingly, geranylgeranylacetone significantly reduced the infarct size (median 31.3% vs 19.9%, p = 0.0013). Conclusions As a preliminary study, these findings suggest that geranylgeranylacetone may be a promising agent for the treatment of ischemic stroke and would be worthy of further study. Further studies are required to clearly delineate the mechanism of geranylgeranylacetone-induced HSP27 phosphorylation in antioxidant effects, which may guide the development of new approaches for minimizing the impact of cerebral ischemia–reperfusion injury.

Although transvenous embolization (TVE) via the superior ophthalmic vein (SOV) is adopted in treating cavernous sinus dural arteriovenous fistula (CS DAVF), its effect on the coil volume is rarely understood. The purpose of the study was to investigate if there is a difference in the total number of coils used and in patient safety when comparing two access strategies. We retrospectively reviewed charts for patients with CS DAVF treated with TVE between January 2008 and March 2018. The baseline patient characteristics, details of procedure, placed coils, and clinical results were compared. A total of 42 patients with CS DAVF were treated with the inferior petrosal sinus (IPS) (n = 32) or SOV (n = 10) approach. TVE via SOV showed a high success rate of 100% (10/10) by transfemoral access. The total number (23 versus 11; P

Background Microvascular decompression (MVD) is the most effective procedure for hemifacial spasm (HFS). MVD results from nonspecialized or low-volume institutes are not always reliable. Most studies on MVD for HFS are retrospective and single centered; to the best of our knowledge, no prospective, multicenter studies exist. Objective To evaluate short- and long-term outcomes and complications in patients who underwent MVD for HFS in specialized Japanese institutions, in this multicenter, prospective, cohort study. Methods Included patients had undergone MVD for HFS in study centers between April 2012 and March 2015. Patients' postoperative grade of involuntary movements and complications were recorded postoperatively at 7 d (short-term) and at 1 (mid-term) and 3 (long-term) yr. Results A total of 486 patients (150 men, 336 women; mean age 53.9 yr with 181 patients over 60 yr) were enrolled during the study period. Neuromonitoring was used in 96.3% of the cases. The complete cure rate of symptom relief, mortality rate, and complication rate at short-term follow-up were 70.6%, 0%, and 15%, respectively. The long-term follow-up was completed by 463 patients (95.3%); the complete cure rate of symptom relief and complication rate were 87.1% and 3.0%, respectively. Conclusion Our study revealed that under expert guidance and intraoperative neuromonitoring, the long-term curative effect rate of MVD for HFS is high, while complications are uncommon and usually transient. Our results indicate that MVD is an effective and safe treatment for patients with HFS, including elderly patients.

Intracranial artery occlusion due to a foreign body is a complication associated with cardiac surgery that is treated by various techniques. However, little is known about appropriate strategies for symptomatic intracranial artery stenosis due to an unknown embolic source. We reported a case of middle cerebral artery (MCA) stenosis after mitral valve repair (MVR) for infective endocarditis (IE). An 80-year-old man presented with right hemiplegia. MR angiography findings were normal, and diffusion-weighted imaging revealed subtle ischemic change in the left MCA territory. The patient was diagnosed with cardioembolic stroke owing to IE and performed MVR. Four days later, he suddenly presented with consciousness disorder and left hemiplegia. Computed tomography (CT) confirmed a very low-density area within the right MCA. MR angiography revealed right MCA stenosis, which corresponded to the low-density area on CT images. Diffusion-weighted imaging revealed new ischemic change in the right MCA territory. Angiography confirmed an irregular stenosis at the right M2 with antegrade blood flow, and the hemiplegia resolved during angiography. Conservative therapy was performed; however, the resting 123 I-IMP-single photon emission CT revealed moderate perfusion defect in the right MCA territory, and transient left hemiplegia appeared every few days. Therefore, 19 days after the initial transient ischemic attack, the patient was performed superficial temporal artery–MCA anastomosis, and the patient responded with a good clinical course without recurrence of the ischemic symptoms. This strategy may be a safe and effective treatment for symptomatic intracranial artery stenosis due to an unknown embolic source.

Each year, the Japan Neurosurgical Society (JNS) reports up-to-date statistics from the Japan Neurosurgical Database regarding case volume, patient demographics, and in-hospital outcomes of the overall cohort and neurosurgical subgroup according to the major classifications of main diagnosis. We hereby report patient demographics, in-hospital mortality, length of hospital stay, purpose of admission, number of medical management, direct surgery, endovascular treatment, and radiosurgery of the patients based on the major classifications and/or main diagnosis registered in 2018 and 2019 in the overall cohort (523283 and 571143 patients, respectively) and neurosurgical subgroup (177184 and 191595 patients, respectively). The patient demographics, disease severity, proportion of purpose of admission (e.g., operation, 33.9-33.5%) and emergent admission (68.4-67.8%), and in-hospital mortality (e.g., cerebrovascular diseases, 6.3-6.5%; brain tumor, 3.1-3%; and neurotrauma, 4.3%) in the overall cohort were comparable between 2018 and 2019. In total, 207783 and 225217 neurosurgical procedures were performed in the neurosurgical subgroup in 2018 and 2019, respectively, of which endovascular treatment comprised 19.1% and 20.3%, respectively. Neurosurgical management of chronic subdural hematoma (19.4-18.9%) and cerebral aneurysm (15.4-14.8%) was most common. Notably, the proportion of management of ischemic stroke/transient ischemic attack, including recombinant tissue plasminogen activator infusion and endovascular acute reperfusion therapy, increased from 7.5% in 2018 to 8.8% in 2019. The JNS statistical update represents a critical resource for the lay public, policy makers, media professionals, neurosurgeons, healthcare administrators, researchers, health advocates, and others seeking the best available data on neurosurgical practice.

Background Aneurysms at the origin of a duplicated middle cerebral artery (DMCA) are quite rare. Here, we report a patient with such an aneurysm successfully treated endovascularly using our novel “wrapped-candy” low-profile visualized intraluminal support (LVIS) technique. Case Description A 44-year-old woman underwent endovascular treatment for an unruptured wide-necked aneurysm at the origin of a DMCA that incorporated the origin of the DMCA into its neck. Stent-assisted coiling was performed using our newly developed “wrapped-candy” LVIS technique. To protect the origin of the DMCA and increase the stent metal density at the neck, an LVIS blue 3.5-mm × 22-mm stent was deployed by pushing the delivery wire aggressively to transform the visible wire components of the LVIS into a shape like “wrapped candy,” maximizing the strut compaction at the neck of the aneurysm. Subsequently, the aneurysm component was coiled using a jailed microcatheter. The final procedural angiography demonstrated almost complete aneurysm occlusion with DMCA preservation. Conclusions Stent-assisted coiling can be a feasible treatment for an unruptured, usually wide-necked, aneurysm at the origin of a DMCA. The wrapped-candy LVIS technique may be useful in more challenging morphologies such as wide-necked aneurysms that incorporate the branch origin into the aneurysm neck.

Treating carotid blowout syndrome following rupture of giant pseudoaneurysms is difficult because the destroyed parent artery precludes conventional treatment. We present a patient with a ruptured giant pseudoaneurysm that we occluded using a modified internal trapping technique with low-concentration N-butyl-2-cyanoacrylate (NBCA) and a minimum number of coils. An 80-year-old man with a history of chemoradiation therapy for oropharyngeal cancer presented with several episodes of active bleeding from the subsequent tracheostomy site. Radiological examination revealed a giant right common carotid artery (CCA) pseudoaneurysm. Endovascular internal trapping was performed using both NBCA and coils under proximal flow control. We slowly injected 9 ml of low-concentration NBCA, which subsequently filled the entire pseudoaneurysm. We then injected an additional 2 ml of NBCA into the proximal CCA to achieve complete obliteration. No re-bleeding was observed during the 6-month follow-up. Endovascular internal trapping using low-concentration NBCA was feasible to treat a giant CCA pseudoaneurysm. The injected low-concentration NBCA filled the entire pseudoaneurysm without the risk of catheter entrapment.

Background Mechanical thrombectomy has become the standard treatment for acute ischemic stroke caused by large vessel occlusion; however, refractory occlusions still occur despite various thrombectomy procedures. The double stent retriever (SR) technique, which employs 2 SRs simultaneously at the occlusion, can be useful for such refractory occlusions. Methods We described 2 cases of refractory acute cerebral occlusion despite the use of conventional thrombectomy procedures that were both treated with the double SR technique. To discuss the technical aspects of how this easy-to-perform technique facilitates the device-clot interaction, we also evaluated radiographic findings of the SR strut during the procedure. Results In both cases, conventional thrombectomy procedures, including an SR alone, an aspiration catheter alone, and combined use of the SR and aspiration catheter, failed to recanalize the occlusion. The double SR technique was then performed with the stent-in-stent method in 1 patient and the parallel stent method in 1 patient. One pass of this technique retrieved hard clots and successfully recanalized the refractory occlusion in both cases. Intraprocedural radiographic images of these cases showed that the degree of stent expansion improved after deployment of the second SR compared with the first SR. Conclusions Our radiographic findings suggested that adding a second SR facilitates the device-clot interaction at the occlusion site. The double SR technique may be an easy-to-perform thrombectomy technique to improve clot-capturing ability for the management of refractory acute cerebral artery occlusions.

Although ultrasonographically-guided carotid interventions without contrast medium have been reported in the literature, we found no report regarding stenting of the vertebral artery origin for treatment of stenosis. Here, we report the case of an iodine-allergic patient in whom a stenosis at the origin of the vertebral artery was successfully treated with ultrasonographically-guided stent placement without contrast medium. B-mode longitudinal images were monitored during the insertion of the embolism-protection device, when positioning the stent, and for the evaluation of the stent opening. This technique can be an alternative option in selected patients, especially those allergic to the contrast medium.

The superior ophthalmic vein (SOV) approach through the facial vein is usually preferred for transvenous embolization of a cavernous sinus dural arteriovenous fistula (CS DAVF) when the ipsilateral inferior petrosal sinus is angiographically occluded. However, navigating the microcatheter can sometimes be difficult because of stenosis or tortuous angulation at the junction between the angular vein and SOV. We present a novel transvenous access route to treat a CS DAVF using the ipsilateral deep facial vein through the SOV to reach the cavernous sinus. A 66-year-old woman presented with left-sided chemosis, exophthalmos, and external ophthalmoplegia. Angiography showed a left CS DAVF associated with a dilated SOV and retrograde cortical venous reflux. A dilated drainage vein, which branched from the SOV, ran through the lateral aspect of the orbit and exited the orbit through the inferior orbital fissure. This vein connected with the ipsilateral deep facial vein draining into the facial and internal jugular veins. We performed transvenous embolization via the SOV approach through the deep facial vein and achieved complete obliteration, by placing 3 platinum coils, without complications. Ophthalmic veins may connect with the cavernous sinus and pterygoid plexus, passing through the superior and inferior orbital fissures, respectively. Our case suggests that the deep facial vein may provide access to the SOV through the inferior orbital fissure without passing the difficult tortuous angle between the angular vein and SOV.

Communicating hydrocephalus is a known tumor-related syndrome associated with vestibular schwannoma, which can occur even in small tumor. Radiation has become a popular primary treatment option for small schwannoma; however, little is known about the efficacy and risk accompanying asymptomatic ventriculomegaly on images. We report a case of a 59-year-old woman who suffer from refractory communicating hydrocephalus after radiation for small vestibular schwannoma with asymptomatic ventriculomegaly. After the surgical removal of the tumor, hydrocephalus was gradually improved due to intermittent lumbar puncture and finally resolved without shunt placement. Surgical removal should be considered as the first option for the treatment, even if the patient is asymptomatic and the images revealed a small vestibular schwannoma with only slight ventricular enlargement.

Background Few studies have examined the usefulness of intraoperative magnetic resonance spectroscopy (iMRS) for identifying abnormal signals at the resection margin during glioma surgery. The aim of this study was to assess the value of iMRS for detecting proliferative remnants of glioma at the resection margin. Methods Fifteen patients with newly diagnosed glioma underwent single-voxel 3-T iMRS concurrently with intraoperative magnetic resonance imaging–assisted surgery. Volumes of interest (VOIs) were placed at T2-hyperintense or contrast-enhancing lesions at the resection margin. In addition to technical verification, the correlation between the MIB-1 labeling index (a pathologic feature) and metabolites measured using iMRS (N-acetyl-L-aspartate [NAA], choline [Cho], and Cho/NAA ratio) was analyzed. Results iMRS was performed for 20 VOIs in 15 patients. Fourteen (70%) of these VOIs were confirmed to be MIB-1–positive. There was a significant positive correlation between the Cho/NAA ratio and MIB-1 index (r = 0.46, P = 0.04). Cho level (P = 0.003) and Cho/NAA ratio (P = 0.002) were significantly higher in VOIs that were MIB-1–positive than in those that were MIB-1–negative. Detection of a Cho level >1.074 mM and a Cho/NAA ratio >0.48 using iMRS resulted in high diagnostic accuracy for MIB-1–positive remnants (Cho level: sensitivity 86%, specificity 100%; Cho/NAA ratio: sensitivity 79%, specificity 100%). Conclusions This study provides evidence that 3-T iMRS can detect proliferative remnants of glioma at the resection margin using the Cho level and Cho/NAA ratio, suggesting that intraoperative magnetic resonance imaging–assisted surgery with iMRS would be practicable in glioma.

Tumor biopsy is essential for the definitive diagnosis of central nervous system (CNS) lymphoma. However, the biopsy procedure carries the risk of complications such as bleeding, convulsions, and infection. Cerebrospinal fluid (CSF) β2‐microglobulin (β2‐MG), soluble IL‐2 receptor (sIL‐2R), and interleukin‐10 (IL‐10) are known to be useful diagnostic biomarkers for CNS lymphoma. The C‐X‐C motif chemokine ligand 13 (CXCL13) was recently reported to be another useful biomarker for CNS lymphoma. The purpose of this study is to establish a diagnostic algorithm that can avoid biopsy by combining these diagnostic biomarkers. In the first, we conducted a case‐control study (n = 248) demonstrating that the CSF CXCL13 concentration was significantly increased in CNS lymphoma patients compared with various other brain diseases (AUC = 0.981). We established a multi‐marker diagnostic model using CSF CXCL13, IL‐10, β2‐MG, and sIL‐2R from the results of the case‐control study and then applied the model to a prospective study (n = 104) to evaluate its utility. The multi‐marker diagnostic algorithms had excellent diagnostic performance: the sensitivity, specificity, positive predictive value, and negative predictive value were 97%, 97%, 94%, and 99%, respectively. In addition, CSF CXCL13 was a prognostic biomarker for CNS lymphoma patients. Our study suggests that multi‐marker algorithms are important diagnostic tools for patients with CNS lymphoma., A comparison of the cerebrospinal fluid (CSF) concentrations of CXCL13 between CNS lymphomas and other CNS diseases. The CSF CXCL13 levels of CNS lymphoma were significantly higher than those of the other diseases. The CXCL13 expression levels increased in the CNS lymphoma specimens compared with the other tumor specimens. The multi‐marker prediction algorithms based on CSF CXCL13, IL‐10, sIL‐2R, and β2‐MG had excellent diagnostic performance.

We present a unique sinus protection technique that uses a short-length supercompliant balloon during the transarterial Onyx embolization for the dural arteriovenous fistula (DAVF) of the lateral tentorial sinus. With this technique, we temporarily change the Borden classification from type II to type III, avoiding venous compromise and reducing the risk of Onyx migration into the patent sinus. A 54-year-old man presented with left persistent tinnitus of 4 months’ duration. Cerebral angiography revealed a Borden type II left lateral tentorial sinus-DAVF associated with retrograde cortical venous reflux draining into the vein of Labbé. In the venous phase, the ipsilateral transverse-sigmoid sinus was recognized as a functional sinus and the posterior temporal vein drained into the transverse sinus near the drainage channel. We planned to perform transarterial Onyx embolization using a short-length sinus protection balloon to protect against Onyx migration. During transarterial Onyx injection, a 7 × 7-mm HyperForm balloon was navigated into the affected sinus and positioned to cover the drainage channel from the shunt. After confirming the change in Borden classification with angiography, transarterial Onyx embolization was performed via the middle meningeal artery. This procedure resulted in complete obliteration of the fistula with good patency of both the transverse-sigmoid sinus and neighboring normal cortical veins. No procedure-related complications were observed and the patient remained free of recurrence during the 24-month follow-up period. Short-length balloon-protected Onyx embolization can be safe and effective for the treatment of Borden type II DAVF. Keywords: HyperForm balloon, Lateral tentorial sinus, Onyx, Sinus protection, Tentorial dural arteriovenous fistula

Background The differences between 3-dimensional (3D) high definition (HD) and 2-dimensional (2D) 4-K ultra-HD (4K) endoscopy and their respective advantages remain unclear. Objective To evaluate the utility of these endoscopy systems in endonasal skull base surgery. Methods Consecutive series of endoscopic endonasal surgeries performed after introduction of 3D/HD and 2D/4K systems (July 2017) were retrospectively evaluated. Sporadic cases treated with either system, or a conventional 2D standard definition (SD) system, during the rental period from March 2016 were also included. Objective comparisons between the systems were made for newly diagnosed Knosp grade 0 to 3 pituitary adenomas. Surgical procedures were divided into nasal, sphenoidal, and intradural phases, and the surgical procedural time was compared for each phase. The time required for and accuracy of suturing the sellar floor dura was also evaluated. Results A total of 74 cases were treated with 3D/HD and/or 2D/4K, and 12 cases with 2D/SD. 3D/HD was advantageous in the nasal phase because of its intuitive depth perception. 2D/4K was advantageous in the intradural phase because of its superior image quality. Surgical time of the nasal phase with 3D/HD, and that of the intradural phase with 2D/4K, were significantly shorter than that with 2D/SD. The time required for and accuracy of sellar floor dural suturing showed a trend toward improving in the order of 2D/SD, 2D/4K, and 3D/HD. Conclusion 3D/HD and 2D/4K endoscopy systems have different advantages, which are useful in distinct surgical phases. Understanding the characteristics of endoscopy systems is important for selecting the most appropriate system for distinct surgical situations.

Objective Postoperative headache (POH) is a disturbing symptom following vestibular schwannoma (VS) resection. However, there are currently no treatment guidelines. The aim of this study was to evaluate the usefulness of symptom-based opioid-free treatments for persistent POH following VS resection. Methods Of 137 patients in whom sporadic VS was resected via the retrosigmoid approach, 74 had persistent POH beyond 3 postoperative months. Their symptoms were classified as tension-type headache, migraine, neuralgia, or other and were treated. We retrospectively analyzed the treatment outcomes during 2 postoperative years. Results Patients with persistent POH were significantly younger (P = 0.003) and had significantly smaller tumors (P = 0.001) and greater extent of resection (P = 0.04) than patients without POH. The most common simple symptom was tension-type headache in 56 patients, followed by migraine in 6 patients and neuralgia in 5 patients. All 7 patients with complex symptoms had a mixture of tension-type headache and migraine. Complete disappearance of POH was achieved in 40 (54%) patients, and a medication-free condition was achieved in 51 (69%). No patients had residual severe POH that could not be controlled with medication. Achievement of a medication-free outcome that included complete disappearance of persistent POH was significantly more common in patients with preserved facial nerve function (P = 0.008) and patients with simple symptoms (P < 0.001). Conclusions A symptom-based approach is appropriate for understanding and managing persistent POH after VS resection with excellent pain control. Preserved facial nerve function and simple symptoms are significant prognostic factors for a medication-free outcome.

Background Reconstructive endovascular treatment is a method that can ameliorate vertebral artery dissecting aneurysm (VADA) and preserve the parent artery. Recently, 2 or 3 overlapping stents have been used to treat VADAs through the flow-diversion effect. However, little is known about the use of >3 overlapping stents for acute treatment of hemorrhagic VADA. Case Description A 69-year-old woman was admitted to our institute with the sudden onset of a headache. Brain computed tomography revealed a subarachnoid hemorrhage. Cerebral angiography revealed a VADA in the right intracranial vertebral artery. The contralateral vertebral artery was hypoplastic; thus we performed a reconstructive endovascular procedure using multiple overlapping stents combined with coiling. We used 5 overlapping stents with the aim of preventing coil herniation, fixing the jailed microcatheter, and reinforcing flow diversion and achieved immediate occlusion of the aneurysmal component. Postoperative imaging showed no apparent infarction in the brainstem. Six months after the treatment, angiography revealed complete occlusion of the aneurysm. Therefore in this case, hemorrhagic VADA was successfully treated in the acute setting by 5 overlapping Enterprise stents and coiling, which also preserved the parent artery. Conclusions Reconstructive endovascular treatment using multiple overlapping stents and coiling may be a beneficial therapy for hemorrhagic VADA, especially when the contralateral vertebral artery is aplastic or hypoplastic. Using >3 overlapping stents may represent a promising, feasible technique for achieving immediate occlusion by increasing flow diversion.

We describe a unique technique to reduce the amount of contrast medium by injecting diluted contrast medium from the microcatheter during neurointervention. A patient with severe renal impairment due to polycystic kidney was referred for endovascular surgery for wide-neck middle cerebral artery aneurysm. In order to reduce the amount of contrast medium, contrast medium was injected from the microcatheter placed in the middle cerebral artery during coil embolization; renal function decline was not observed after the procedure. This technique, therefore, reduces the amount of contrast medium and enables one to perform coil embolization safely. Key words: Chronic kidney disease, Coil embolization, Contrast medium, Contrast-induced nephropathy

Lattice Boltzmann simulations of flows in TOF-MRA-based cerebral aneurysm models are carried out using the single-, two- and multiple-relaxation time collision models, SRT, TRT and MRT, to investigate the effects of the collision model on predicted velocity fields in the aneurysms. The non-Newtonian characteristics of blood are accounted for by using the Casson model, whereas a simulation with the Newtonian viscous stress model is also carried out to investigate the effects of the viscous stress model on predicted velocity and wall shear stress distributions. Four cerebral aneurysm models are used in the simulation. The shapes of cerebral arteries are extracted from TOF-MRA data as STL meshes, and the level set function representing the artery wall is reconstructed from the STL mesh data. By making use of the level set function in the interpolated bounce-back scheme, the complex structures of arteries having aneurysms can be easily dealt with in the LB framework. As a result, the following conclusions are obtained: (1) the SRT can give reasonable predictions comparable to the MRT, provided that the spatial resolution is high enough; otherwise numerical errors can be large and numerical instabilities take place, (2) numerical errors in velocity is apt to take place in the near aneurysm wall region due to a small velocity scale, (3) although the TRT is less stable than the MRT, predictions of the TRT under stable numerical conditions are almost the same as those of the MRT, and (4) although the Bingham number effect on the flow structure is small, the mean wall shear stress may change over several percent, depending on the configuration of the aneurysm and the main blood flow, by neglecting the non-Newtonian nature of blood.