Declining trend in the estimated annual rupture rate of unruptured cerebral aneurysms in Japan: a nationwide study.

The incidence of subarachnoid hemorrhages (SAHs) in Japan has recently decreased. However, trends in the annual rates of unruptured cerebral aneurysms (UCAs) are unclear because calculations based on follow-up periods are limited to patients with ruptured cerebral aneurysms. We aimed to clarify current trends in the estimated annual rupture rates of UCAs in Japan and to identify the most relevant contributing factors. We analyzed data from the Japanese Ministry of Health, Labour and Welfare and records of the Japan Neurosurgical Society. The estimated annual rupture rates of UCAs between 2003 and 2018 were calculated according to age-adjusted mortality rates of SAH and number of treated ruptured cerebral aneurysms (RCAs). We estimated trends in annual rupture rates using sensitivity analysis and assessed associations between estimated annual rupture rates and the prevalences of hypertension and current smoking. The estimated annual rupture rate of UCAs significantly decreased from 1.44 to 0.87% and from 0.92 to 0.76%, respectively, in terms of age-adjusted mortality rates of SAH and number of treated RCAs (p < 0.001). The range of changes in estimated annual rupture rates of UCAs was - 1.13%‒0.83%, representing a declining UCA trend of 88%. The estimated annual rupture rates of UCAs declined by 0.02-0.10% and 0.01-0.05% with every percent decrease in hypertension and current smoking prevalence, respectively. The estimated annual rupture rate of UCAs has recently decreased in Japan, possibly due to a decrease in the prevalence of hypertension rather than smoking.

Surgical Risk in Elderly Patients with Meningiomas in Japan.

Background/Objective: No guidelines indicate surgical risk factors for the elderly because of the lack of data from general neurosurgeons. To better understand the management of surgical risk in elderly patients with meningiomas based on a national database in Japan. Methods: Results of surgically treated meningiomas were explored in 8138 patients registered in the Diagnosis Procedure Combination database in Japan during 2010-2015. Age (<65, 65-74, and ≥75 years), sex, Barthel index (BI), medical history, tumor location, oral medication prescriptions on admission, and stroke complications were evaluated. Multivariate logistic regression analysis identified risk factors for stroke complications, BI deterioration between admission and discharge, and in-hospital mortality. Results: Advanced age was the prominent risk factor for BI deterioration (odds ratio: 3.26; 95% confidence interval: 2.69-3.95) but not for in-hospital mortality. Lower BI (60-80) on admission increased the risk of BI deterioration in all age groups; however, BI < 60 demonstrated a significant inverse risk (0.47; 0.32-0.69) in the elderly (≥75 years). Location (falx, parasagittal, and deep) and anticoagulants were not significant risk factors for BI deterioration in patients aged ≥ 75 years, despite being significant risk factors in patients aged <65 and/or 65-74 years. Conclusions: Although advanced age could lead to postoperative functional decline at discharge, it was not sufficiently significant enough to be associated with in-hospital mortality. Because of the possibility of recovery even in elderly patients with severe disabilities, appropriate surgical selection and optimal management may lead to favorable functional outcomes in elderly patients with meningiomas.

[In-Hospital Arrangements for Preoperative Simulation].

Neurosurgeons of the future must possess the ability to engage in preoperative simulation. However, given the changing medical practices and redistribution of tasks among physicians, the significance of radiological technologists is increasing. In this article, we describe the collaboration between radiological technologists and the hospital system to simplify preoperative simulation for young physicians. Preparation for preoperative simulation is a collaborative process with radiological technologists, aiming to facilitate mutual learning and risk management. It involves recognizing and utilizing the expertise of certified radiological technologists for imaging and additional surgical support, with due consideration given to the additional fees. The creation of an in-hospital arrangement system for preoperative simulation ensures more efficient and safer workflow.

Allogeneic Stem Cell Therapy for Acute Ischemic Stroke: The Phase 2/3 TREASURE Randomized Clinical Trial.

Importance: Cell therapy is a promising treatment approach for stroke and other diseases. However, it is unknown whether MultiStem (HLCM051), a bone marrow-derived, allogeneic, multipotent adult progenitor cell product, has the potential to treat ischemic stroke. Objective: To assess the efficacy and safety of MultiStem when administered within 18 to 36 hours of ischemic stroke onset. Design, Setting, and Participants: The Treatment Evaluation of Acute Stroke Using Regenerative Cells (TREASURE) multicenter, double-blind, parallel-group, placebo-controlled phase 2/3 randomized clinical trial was conducted at 44 academic and clinical centers in Japan between November 15, 2017, and March 29, 2022. Inclusion criteria were age 20 years or older, presence of acute ischemic stroke (National Institutes of Health Stroke Scale [NIHSS] score of 8-20 at baseline), confirmed acute infarction involving the cerebral cortex and measuring more than 2 cm on the major axis (determined with diffusion-weighted magnetic resonance imaging), and a modified Rankin Scale (mRS) score of 0 or 1 before stroke onset. Data analysis was performed between May 9 and August 15, 2022. Exposure: Patients were randomly assigned to either intravenous MultiStem in 1 single unit of 1.2 billion cells or intravenous placebo within 18 to 36 hours of ischemic stroke onset. Main Outcomes and Measures: The primary end points were safety and excellent outcome at day 90, measured as a composite of a modified Rankin Scale (mRS) score of 1 or less, a NIHSS score of 1 or less, and a Barthel index score of 95 or greater. The secondary end points were excellent outcome at day 365, mRS score distribution at days 90 and 365, and mRS score of 0 to 1 and 0 to 2 at day 90. Statistical analysis of efficacy was performed using the Cochran-Mantel-Haenszel test. Results: This study included 206 patients (104 received MultiStem and 102 received placebo). Their mean age was 76.5 (range, 35-95) years, and more than half of patients were men (112 [54.4%]). There were no between-group differences in primary and secondary end points. The proportion of excellent outcomes at day 90 did not differ significantly between the MultiStem and placebo groups (12 [11.5%] vs 10 [9.8%], P = .90; adjusted risk difference, 0.5% [95% CI, -7.3% to 8.3%]). The frequency of adverse events was similar between treatment groups. Conclusions and Relevance: In this randomized clinical trial, intravenous administration of allogeneic cell therapy within 18 to 36 hours of ischemic stroke onset was safe but did not improve short-term outcomes. Further research is needed to determine whether MultiStem therapy for ischemic stroke has a beneficial effect in patients who meet specific criteria, as indicated by the exploratory analyses in this study. Trial Registration: ClinicalTrials.gov Identifier: NCT02961504.

[A Surgical Case of Currarino Syndrome with Syringomyelia].

Currarino syndrome is characterized by a triad of anorectal malformations, sacral defects, and presacral masses. Although it is not extremely rare, this report presents a surgical case of Currarino syndrome with syringomyelia and discusses related literature. The patient is a girl, aged 2 years and 2 months, who presented with marked constipation, chronic cystitis, and lower limb weakness. After examining the patient through magnetic resonance imaging, we diagnosed her with rectal compression due to meningocele and syringomyelia. The base of the meningocele was detached, and the spinal cord was untethered. One week after surgery, her lower limb weakness and constipation improved. Following up on symptoms and performing imaging is essential to determine a treatment plan for Currarino syndrome. (Received 28 February, 2023; Accepted 22 March, 2023; Published 1 August, 2023).

The 5-Factor Modified Frailty Index as a More Useful Associated Factor Than Chronological Age After Unruptured Cerebral Aneurysm Surgery: A Nationwide Registry Study.

BACKGROUND: Although chronological age is associated with mortality and morbidity after surgery for unruptured cerebral aneurysms (UCAs), there is little evidence regarding an association between the simplified 5-factor modified frailty index (mFI-5) and postoperative outcomes based on age group. OBJECTIVE: To investigate the association of the mFI-5 score with worse outcomes, mortality, and complications in patients after surgery for UCA by chronological age groups using a Japanese national database. METHODS: This study included 32 902 patients with UCAs enrolled in a Japanese national database between 2011 and 2015. Age group (younger than 65 years, 65-74 years, and 75 years or older), sex, UCA location, treatment, medications, Barthel Index (BI), medical history, mFI-5 score, and in-hospital mortality and complications were evaluated. We identified risk factors for worsening BI score, in-hospital mortality, and overall postoperative complications in each age group. RESULTS: In total, 14 465 patients were enrolled in this study. Multivariable analysis showed that elderly groups and patients with an mFI-5 score ≥2 items were associated with worsening BI scores (odds ratio 1.95; 95% CI 1.52-2.51) and in-hospital complications (odds ratio 1.79; CI 1.49-2.15), despite having no association with in-hospital mortality. Multivariable analysis by age groups showed that the mFI-5 score ≥2 items was associated with in-hospital complications in all age groups, unlike chronological age in patients younger than 74 years. CONCLUSION: The mFI-5 score was a more useful associated factor of in-hospital complications than chronological age in patients younger than 74 years undergoing surgery for UCA.

Perioperative Surgical Risks in Patients With Hemangioblastomas: A Retrospective Nationwide Review in Japan.

BACKGROUND: The perioperative risk of sporadic hemangioblastomas (HBs) and von Hippel-Lindau disease (VHL)-associated hemangioblastomas (VHL-associated HBs) remains unclear due to the rare prevalence of HB. Therefore, this study aimed to clarify risk factors for better surgical management of patients with HBs. METHODS: A retrospective analysis of surgically treated HB patients registered in the Diagnosis Procedure Combination database of Japan, between 2010 and 2015, was performed. Age, sex, sporadic HBs or VHL-associated HBs, medical history, tumor location, hospital case load, postoperative complications, and Barthel index (BI) deterioration were assessed. We also evaluated the outcomes and factors of perioperative BI deterioration. RESULTS: In total, 676 patients with 609 intracranial lesions, 64 spinal lesions, and 3 with both types were eligible. Among them, 618 and 58 patients had sporadic HBs and VHL-associated HBs, respectively. The rates of perioperative BI deterioration were 12.5% and 12.2% for sporadic HBs and VHL-associated HBs, respectively. Perioperative mortality was 1.8% and 0% for sporadic HBs and VHL-associated HBs, respectively. Male sex, old age, high hospital case load, and medical history of diabetes mellitus were significantly associated with perioperative BI deterioration in all cases and sporadic HBs. Only medical history of diabetes mellitus was a significant risk factor for perioperative BI deterioration in VHL-associated HBs. CONCLUSIONS: No differences in perioperative BI deterioration rates between sporadic HBs and VHL-associated HBs were found. However, different risk factors for perioperative BI deterioration were identified. Consideration of these risk factors is recommended in all patients undergoing surgery for HB.

Male sex and presence of preoperative symptoms are associated with early recurrence of WHO grade I meningiomas after surgical resection: analysis from the nationwide Brain Tumor Registry of Japan.

This study aimed to assess the risk factors for the recurrence of WHO grade I intracranial meningiomas using the Brain Tumor Registry of Japan (BTRJ) database. We extracted the data of 4641 patients with intracranial WHO grade I meningiomas treated only by surgical resection between 2001 and 2008. We conducted complete data analysis (n = 3690) and multiple imputation analysis (n = 4641) to adjust for missing data on tumor size. The influence of factors including age, sex, size, extent of resection, location, and preoperative symptoms on PFS was assessed. Univariate analyses of the complete data set showed that age did not affect PFS; however, male sex (p < 0.001), tumor size ≥ 30 mm (p < 0.001), low extent of resection, tumor location at the skull base (p < 0.001), and the presence of preoperative symptoms (p < 0.001) were risk factors for a significantly shorter PFS. Multivariate analysis demonstrated that male sex (p < 0.001) and presence of preoperative symptoms (p = 0.027) were independent risk factors for shorter PFS alongside large tumor size (p < 0.001) and non-gross total resection (p < 0.001). These results were confirmed for the imputed dataset. While most previous large nationwide studies of meningiomas have evaluated overall survival, progression-free survival has yet to be thoroughly examined. This study suggests that even histologically benign meningiomas may have a sex difference in postoperative behavior. This observation may provide clues to understanding the mechanism of meningioma cell proliferation.

Factors associated with the location of perivascular space enlargement in middle-aged individuals undergoing brain screening in Japan.

OBJECTIVE: In elderly populations, the enlargement of the perivascular space is related to small vessel disease and the glymphatic system. Enlarged perivascular spaces (EPVS) in the basal ganglia (EPVS-BG) and EPVS in the centrum semiovale (EPVS-CSO) are associated with different pathophysiological processes. However, the prevalence of EPVS and the factors associated with EPVS location in healthy middle-aged individuals are still unclear. We aimed to determine the prevalence of EPVS and the factors associated with EPVS location among healthy individuals in their 40 s METHODS: This study included 5000 consecutive healthy individuals who underwent screening for brain diseases in Japan from August to December 2018. Of them, the data of individuals in their 40 s were extracted and analyzed. The associations of age, sex, body mass index, smoking and drinking history, and medical history with EPVS location were investigated. Similar analyses were performed for the other age groups. A literature review on the factors associated with EPVS location was also performed. RESULTS: A total of 1720 individuals in their 40 s were finally included. The prevalence of EPVS-BG and EPVS-CSO was 7.7% and 9.2%, respectively. Age (years), smoking history, and hypertension were associated with EPVS-BG; none of the studied factors were found to be associated with EPVS-CSO. In the elderly, the factors previously reported to be associated with EPVS-BG included atherosclerosis change, while the factors associated with EPVS-CSO were cerebral amyloid angiopathy-related formation. CONCLUSION: Both EPVS-BG and EPVS-CSO occurred among healthy individuals in their 40 s, but they did so rarely, and less prevalently than in older age groups. EPVS-BG and EPVS-CSO may represent early imaging signs of the atherosclerotic and cerebral amyloid angiopathy processes, respectively. DATA AVAILABILITY: The anonymized data for this study will be shared upon any qualified investigator's request to the corresponding author. Primary data from this study will be made available upon reasonable request in accordance with the review board of the research institute.

A nationwide registry study: The 5-factor modified frailty index of meningioma surgery in non-elderly and elderly patients.

OBJECTIVES: The simplified 5-factor modified frailty index (mFI-5) is a useful indicator of outcome for patients undergoing surgeries as frailty is considered an important risk factor in elderly patients. However, its usefulness has not been validated based on age groups. Therefore, we aimed to investigate risk factors, including the mFI-5, across age groups for complications and worse outcomes in meningioma surgery using data obtained from the nationwide database in Japan. METHODS: We extracted data from the nationwide registry database in Japan between 2010 and 2015. Age (< 65, 65-74, and ≥ 75 years), sex, Barthel Index (BI), mFI-5 scores, and complications were evaluated. Multivariate logistic regression analyses identified risk factors for worsening BI scores and complications after surgery across all age groups. RESULTS: Among 8138 included patients, an mFI-5 score ≥ 2 items was a significant risk factor for worsening BI scores in patients aged < 65 years (odds ratio: 2.3; 95 % confidence interval: 1.5-3.4), but not in patients aged 65-74 years and those aged ≥ 75 years, contrary to chronological age. Similar results were noted for any complications in patients aged < 65 years (2.5; 1.8-3.6) and aged 65-74 years (1.5; 1.1-2.1), but not in patients aged ≥ 75 years. CONCLUSION: Although the mFI-5 scores could predict the risk of in-hospital worsening outcomes, mortality, and complications, it was more useful in non-elderly patients aged < 65 years rather than in elderly patients aged ≥ 75 years, contrary to chronological age. Further prospective studies should be performed in the future to clarify the utility of the mFI-5.

[Practical Guidelines for the Appropriate Use of Antimicrobial Agents for Prevention of Surgical Site Infection in Various Neurosurgical Fields].

Preoperative shaving and disinfection; postoperative wound care; and preoperative, intraoperative, and postoperative antibiotic use are the main methods used to prevent perioperative surgical site infection(SSI); however, a survey of neurosurgeons in Japan did not indicate that these guidelines were followed. There are several types of surgical procedures in the field of neurosurgery, including implant insertion, with little evidence of use of antimicrobial agents in such surgeries. Hence, there had been no guidelines for antimicrobial use in neurosurgery in Japan. However, practice guidelines for the appropriate use of antimicrobial agents for the prevention of postoperative infection in neurosurgery were published in 2020 and are discussed in this section.

Effect of adjuvant radiotherapy after subtotal resection for WHO grade I meningioma: a propensity score matching analysis of the Brain Tumor Registry of Japan.

PURPOSE: This study aimed to improve the understanding of the role of adjuvant radiotherapy (AR) after subtotal resection (STR) of World Health Organization (WHO) grade I meningiomas. METHODS: We retrospectively reviewed the Brain Tumor Registry of Japan database. Among 7341 patients diagnosed with intracranial meningioma during 2001-2008, we identified 406 patients with WHO grade I meningioma treated with STR as initial treatment. Data on progression-free survival (PFS) were assessed for their relevance to clinical factors including age, sex, tumor location and size, presence of preoperative symptoms, and AR. RESULTS: AR was administered for 73 patients (18.0%). Regrowth occurred in 90 cases (22.2%) during the median follow-up period of 6.0 years (interquartile range, 2.7-7.7 years). Multivariate Cox regression analysis of the entire cohort showed that no AR was associated with significantly shorter PFS (hazard ratio [HR] 2.52, 95% confidence interval [CI] 1.33-5.42, p = 0.004). The therapeutic effect of AR was confirmed for skull base, but not non-skull base, meningiomas (p = 0.003 and 0.69, respectively). Propensity score matching analysis balanced the influence of confounding factors to generate AR+ and AR- cohorts of 73 patients each. PFS was significantly longer in the AR+ cohort than in the AR- cohort (HR 3.46, 95% CI 1.53-8.59, p = 0.003). Subgroup analysis demonstrated the favorable effect of AR only for skull base meningiomas. CONCLUSIONS: Our study revealed that AR improves tumor control after STR in WHO grade I meningiomas. However, this beneficial effect might be limited to skull base meningiomas.

In-Hospital Complications After Surgery in Elderly Patients with Asymptomatic or Minor Symptom Meningioma: A Nationwide Registry Study.

BACKGROUND: Asymptomatic or minor symptom meningiomas (AMSMs) in the elderly are incidental findings, with no consensus reached on the optimal management strategy. In the present study, we aimed to determine the surgical risk factors for elderly patients with AMSMs using a nationwide registry database in Japan. METHODS: We identified patients with surgically treated AMSMs using the Diagnosis Procedure Combination database from 2010 to 2015 and reviewed the medical records for age (<65 years; pre-elderly, 65-74 years; and elderly, ≥75 years), sex, Barthel index (BI) score, medical history, tumor location, and complications. An AMSM was defined by a BI score of 100 points at admission. The risk factors for all stroke complications, BI deterioration at discharge, and in-hospital mortality were determined using multivariate logistic regression analyses. RESULTS: From a total of 10,535 patients with meningioma, 6628 were included. Advanced age was a significant risk factor (odds ratio, 3.54; 95% confidence interval, 2.80-4.46) for BI deterioration but not for all-stroke complications or in-hospital mortality. Midline and posterior fossa tumors, diabetes mellitus, and chronic heart disease were significant risk factors for in-hospital mortality. CONCLUSIONS: For elderly patients with surgically treated AMSMs, advanced age was a prominent risk factor for functional decline at discharge. Our study identified several factors that should be evaluated before proceeding with surgery for AMSMs in elderly and pre-elderly patients. These findings could, not only improve decision-making among clinicians treating patients with AMSMs, but also help in predicting the results of surgery for elderly patients with AMSMs.

Nation-wide Brain Tumor Registry-based Study of Intracranial Meningioma in Japan: Analysis of Surgery-related Risks.

Although surgical resection is the most preferred treatment for intracranial meningiomas, a detailed analysis of the surgery-related risks based on large population data has not been conducted to date. In this study, we analyzed the nation-wide brain tumor registry to assess the surgical risk factors for intracranial meningiomas to provide information for an optimal treatment strategy. Data of 4081 meningioma patients who underwent initial resection between 2001 and 2008 were extracted from the Brain Tumor Registry of Japan (BTRJ) database and reviewed for postoperative mortality, aggravation of Karnofsky Performance Score (KPS), and complications. The total in-hospital mortality rate was 0.59%. Male sex and tumor size ≥30 mm were independent risk factors for mortality. Among 4081 cases, 4.4% of patients had KPS that were lowered by 20 or more points at the time of discharge after surgery. Age ≥65 years, higher WHO grading, tumor location at the skull base, tumor size ≥30 mm, and non-gross total resections were associated with lowering of KPS scores by 20 or more points. The overall incidence of surgical complications was 19.3%. The rate of occurrence of new postoperative seizure in patients with supratentorial meningioma was 10.9%. All complications except for vascular complications occurred with significantly lower frequencies in asymptomatic patients than in symptomatic patients. Our results provide useful information regarding the surgical risks when surgical intervention is being considered for intracranial meningiomas. Surgery is an important option for asymptomatic meningiomas as the mortality rate and complication rate in the current study were sufficiently low.

Risk Factor for Poor Outcome in Elderly Patients with Aneurysmal Subarachnoid Hemorrhage Based on Post Hoc Analysis of the Modified WFNS Scale Study.

OBJECTIVE: There is currently no precise guide for the treatment and management of elderly patients with aneurysmal subarachnoid hemorrhage (aSAH). Thus, the aim of this study was to clarify the factors of poor outcome and mortality in elderly patients with aSAH. METHODS: In the modified World Federation of Neurosurgical Societies (mWFNS) scale study, 1124 patients were divided into 2 groups, elderly (age ≥65 years) and non-elderly (age <65 years), with aSAH investigated between October 2010 and March 2013 in Japan. The odds ratio (OR) and 95% confidence interval (CI) of each risk factor was calculated through multivariate logistic regression analysis for poor outcomes, as indicated by the modified Rankin Scale (mRS) score ≥3 and mortality at 3 months after onset in each group. RESULTS: Both groups demonstrated that the mWFNS scale was significant as a grade order risk factor for poor outcomes and mortality associated with disease. In the elderly group, risk factors for poor outcomes at 3 months after onset were older age (OR 1.10, 95% CI 1.06-1.14), male sex (OR 2.03, 95% CI 1.10-3.73), and severe cerebral vasospasm category (OR 10.13, 95% CI 4.30-23.87). Risk factors for mortality at 3 months after onset were older age (OR 1.06, 95% CI 1.01-1.11) and severe vasospasm category (OR 2.17, 95% CI 1.00-4.72). CONCLUSIONS: The mWFNS scale is a useful prognostic predictor for both non-elderly and elderly patients with aSAH. Elderly male patients with aSAH presenting with severe vasospasm should be managed more carefully.

A register-based SAH study in Japan: high incidence rate and recent decline trend based on lifestyle.

OBJECTIVE: Japan has been reported to have the highest (and increasing) incidence of subarachnoid hemorrhage (SAH) in the world. However, there has never been a report on the nationwide incidence rate and recent trends for SAH in Japan. In this register-based study, the authors aimed to clarify the estimated nationwide SAH incidence rate and the recent trend in SAH incidence in Japan and the reasons for any changes in this trend. METHODS: The authors compiled data from the Japanese Ministry of Health, Labour and Welfare and from the records of the Japan Neurosurgical Society. They reviewed the age-standardized nationwide SAH mortality rate, the estimated age-standardized SAH incidence rate according to the age-standardized SAH mortality rate, and the estimated crude SAH incidence rate, including the 95% confidence intervals, from 2003 to 2015. The trends in the number of treatments for unruptured and ruptured cerebral aneurysms, as well as the prevalence of hypertension, current smoking status, and use of cholesterol-lowering drugs, were assessed. The estimated treatment rate for unruptured cerebral aneurysms (UCAs) was also calculated along with the 95% confidence interval. RESULTS: The estimated age-standardized nationwide SAH incidence rate significantly declined from 31.34 cases (95% CI 31.32-31.34) to 27.63 (95% CI 27.59-27.63; decrease by 11.8%) per 100,000 person-years. This decline was based on the 2010 population as the reference from 2003 through 2015 and a case-fatality rate of SAH that was assumed to decrease by 1% annually from 44% in 2003 to 32% in 2015. According to sensitivity analysis, the change rate of the estimated age-standardized SAH incidence rate ranged from -56.69% to 23.27%, with a mean of -30.91% (SD 20.52%), and there were decline trends in 92% of all trends. The estimated nationwide crude SAH incidence rate also showed a significant decline from 23.79 (95% CI 23.78-23.79) to 20.25 (95% CI 20.24-20.25; decrease by 14.9%) per 100,000 person-years. The trend in treatment numbers for UCAs increased significantly (p < 0.0001) from 2003 through 2015; however, the estimated treatment rate for UCAs was only 0.19 (95% CI 0.19-0.20) to 0.51 (95% CI 0.50-0.51) among all UCA patients. The prevalence of hypertension (males, p = 0.0003; females, p < 0.0001) and current smoking status (males, p < 0.0001; females, p = 0.0002) declined significantly from 2003 through 2015, while the use of cholesterol-lowering drugs increased significantly (males, p < 0.0001; females, p = 0.0005) during the same period. CONCLUSIONS: The estimated nationwide SAH incidence rate in Japan was higher than rates in other countries, although it has declined recently. An improving lifestyle may have contributed to the declining rate of SAH incidence in Japan.

Characteristics of Cerebral Aneurysms in Japan.

The characteristics of cerebral aneurysms in Japan differ from other countries in the higher incidence of unruptured cerebral aneurysm detected by brain check-up screening, higher rupture rate of unruptured cerebral aneurysm, higher incidence of subarachnoid hemorrhage, and superior outcome after subarachnoid hemorrhage based on meta-analysis. Head shape, genetic features, environmental factors, demographics, and medical system in Japan are also different from other countries. Unruptured cerebral aneurysms are 2.8 times more likely to rupture in Japanese than western aneurysms, resulting in the highest incidence of subarachnoid hemorrhage in the world. The exact and specific mechanisms of de novo, growth, and rupture of cerebral aneurysms have not been elucidated. Investigations will contribute to the understanding of cerebral aneurysms and subarachnoid hemorrhage worldwide. Some features of cerebral aneurysm in Japan are discussed for possible research guidance in the elucidation of the predominance of subarachnoid hemorrhage in Japan.

Questionnaire Survey Regarding Prevention of Surgical Site Infection after Neurosurgery in Japan: Focus on Perioperative Management and Administration of Surgical Antibiotic Prophylaxis.

Various guidelines regarding surgical site infection (SSI) have recently been established. However, perioperative management of the wound and use of antibiotics have never been standardized completely in departments of neurosurgery in Japan. This survey investigated current perioperative management and administration of surgical antibiotic prophylaxis (SAP) and compared with guidelines intended to reduce SSI associated with neurosurgery in Japan. Questionnaires were distributed to members of the conference on Neurosurgical Techniques and Tools and the Japan Society of Aesthetic Neurosurgery via internet. The questionnaires asked about methods of perioperative management. A total of 255 members returned answers to the questionnaires. The questionnaires revealed that partial or no removal of the hair and hair shampooing at the day before surgery were performed in 96.1% and 88.1% of each institute following the World Health Organization (WHO) guidelines. Use of SAP at just before, during, and after surgery were 65.0%, 86.2%, and 63.0%, respectively. The postoperative period of use of intravenous SAP prolonged beyond 24 h in 80.0% against the recommendation of WHO. Perioperative management of wounds and use of SAP varies in institutes in Japan and some procedures were far different from the WHO guidelines. Japanese neurosurgeons should notice the prolonged SAP and comply with the WHO guidelines.

Usefulness of Preoperative Simulation in Skull Base Approach: A Case Report.

Skull base approach is a neurosurgical challenge requiring dexterity of the operating surgeon for good postoperative outcome. In addition to the experience of the operating surgeon, adequate preoperative information of the tumor is necessary to ensure better outcome. In clinoid meningioma, it is sometimes difficult to determine its relationship with the surrounding structure and the feeding artery. Previously, preoperative simulation has been utilized to determine the intracranial course of the compressed nerves in relation to the petroclival meningioma. We report a case of clinoid meningioma where preoperative fusion of three dimensional computed tomography angiography (3D-CTA) and 3T-fast imaging employing steady-state acquisition (FIESTA) images was useful in determining the exact location of the feeding artery to devascularize the tumor and aid in surgery. Preoperative simulation with three-dimensional digital subtraction angiography (3D-DSA) and 3T-FIESTA fusion images can be a useful adjunct tool to supplement surgery and to train neurosurgical trainees.

Factors Related to Frailty Associated with Clinical Deterioration After Meningioma Surgery in the Elderly.

BACKGROUND: Older patients are increasingly presenting for surgery with intracranial meningioma because of progress with diagnostic imaging and longer life expectancy. However, older patients have many problems, such as comorbidities and reduced physiological capacity reflected in the frailty index. This study examines the factors affecting clinical deterioration after surgery in older patients, particularly factors associated with frailty. METHODS: Two hundred sixty-five patients older than 65 years underwent surgical resection of meningioma at Hiroshima University and related hospitals between 2000 and 2016. Karnofsky Performance Status (KPS) scores before and after surgery were evaluated. Factors related to the deterioration of KPS were analyzed with multivariate logistic regression modeling, including body mass index and serum albumin. RESULTS: KPS score deteriorated compared with preoperative score in 56 patients at discharge and in 40 patients at 3 months later, and 2 patients died within 1 year after surgery. Multivariate logistic regression analysis in addition to preoperative body mass index and serum albumin indicated skull base tumor location (odds ratio [OR], 4.67; 95% confidence interval [CI], 2.02-10.8) and serum albumin (OR, 2.38; 95% CI, 1.06-5.34) were risk factors for deterioration of KPS score at discharge. Age (OR, 0.91; 95% CI, 0.85-0.98), skull base tumor location (OR, 4.32; 95% CI, 1.45-12.9), tumor size (OR, 1.03; 95% CI, 1.00-1.05), and serum albumin (OR, 3.53; 95% CI, 1.29-9.61) were significant risk factors for perioperative intracranial complications. CONCLUSIONS: Skull base tumor location and serum albumin correlated with deterioration of clinical status after surgery.