Cerebral Small Vessel Disease Burden for Bleeding Risk during Antithrombotic Therapy: Bleeding with Antithrombotic Therapy 2 Study

OBJECTIVE

This study was undertaken to determine the excess risk of antithrombotic-related bleeding due to cerebral small vessel disease (SVD) burden.

METHODS

In this observational, prospective cohort study, patients with cerebrovascular or cardiovascular diseases taking oral antithrombotic agents were enrolled from 52 hospitals across Japan between 2016 and 2019. Baseline multimodal magnetic resonance imaging acquired under prespecified conditions was assessed by a central diagnostic radiology committee to calculate total SVD score. The primary outcome was major bleeding. Secondary outcomes included bleeding at each site and ischemic events.

RESULTS

Of the analyzed 5,250 patients (1,736 women; median age = 73 years, 9,933 patient-years of follow-up), antiplatelets and anticoagulants were administered at baseline in 3,948 and 1,565, respectively. Median SVD score was 2 (interquartile range = 1-3). Incidence rate of major bleeding was 0.39 (per 100 patinet-years) in score 0, 0.56 in score 1, 0.91 in score 2, 1.35 in score 3, and 2.24 in score 4 (adjusted hazard ratio [aHR] for score 4 vs 0 = 5.47, 95% confidence interval [CI] = 2.26-13.23), that of intracranial hemorrhage was 0.11, 0.33, 0.58, 0.99, and 1.06, respectively (aHR = 9.29, 95% CI = 1.99-43.35), and that of ischemic event was 1.82, 2.27, 3.04, 3.91, and 4.07, respectively (aHR = 1.76, 95% CI = 1.08-2.86). In addition, extracranial major bleeding (aHR = 3.43, 95% CI = 1.13-10.38) and gastrointestinal bleeding (aHR = 2.54, 95% CI = 1.02-6.35) significantly increased in SVD score 4 compared to score 0.

INTERPRETATION

Total SVD score was predictive for intracranial hemorrhage and probably for extracranial bleeding, suggesting the broader clinical relevance of cerebral SVD as a marker for safe implementation of antithrombotic therapy. ANN NEUROL 2024;95:774-787.

Associations for progression of cerebral small vessel disease burden in healthy adults: the Kashima scan study

To investigate the association between vascular risk factors and progression of cerebral small vessel disease (SVD), we conducted a longitudinal study with neurologically healthy cohort composed mostly of middle-aged adults (n = 665, mean age, 57.7 years). Subjects, who had both baseline data of brain health examinations including MRI and follow-up MRI at least 1 year after the baseline MRI, were included this study. The presence of features of SVD, including lacunes, cerebral microbleeds, white matter hyperintensity, and basal ganglia perivascular spaces were summed to obtain "total SVD score" (range, 0-4). Progression of SVD was evaluated among subjects with a total SVD score of ≤ 3 and was defined as a ≥ 1 point increase in that score at follow-up relative to baseline. As the primary analysis, multivariate logistic regression analyses were performed to determine the associations of progression of SVD at baseline. The median follow-up period was 7.3 years and progression of SVD was observed in 154 subjects (23.2%). Even after adjustment with confounders multivariate logistic regression analyses showed that progression of SVD was associated with age (per 10-year increase, odds ratio [OR]: 2.08, 95% confidence interval [CI] 1.62-2.67), hypertension (OR 1.55, 95%CI 1.05-2.29), systolic blood pressure (BP) (per standard deviation [SD] increase, OR 1.27, 95%CI 1.04-1.54), diastolic BP (per SD increase, OR 1.23, 95%CI 1.01-1.50), and mean arterial pressure (per SD increase, OR 1.27, 95%CI 1.04-1.55). Age and high blood pressure appear to play key roles in the progression of cerebral small vessel burden after mid-life.

Clinical Associations and Prognostic Value of MRI-Visible Perivascular Spaces in Patients With Ischemic Stroke or TIA: A Pooled Analysis

BACKGROUND AND OBJECTIVES

Visible perivascular spaces are an MRI marker of cerebral small vessel disease and might predict future stroke. However, results from existing studies vary. We aimed to clarify this through a large collaborative multicenter analysis.

METHODS

We pooled individual patient data from a consortium of prospective cohort studies. Participants had recent ischemic stroke or transient ischemic attack (TIA), underwent baseline MRI, and were followed up for ischemic stroke and symptomatic intracranial hemorrhage (ICH). Perivascular spaces in the basal ganglia (BGPVS) and perivascular spaces in the centrum semiovale (CSOPVS) were rated locally using a validated visual scale. We investigated clinical and radiologic associations cross-sectionally using multinomial logistic regression and prospective associations with ischemic stroke and ICH using Cox regression.

RESULTS

We included 7,778 participants (mean age 70.6 years; 42.7% female) from 16 studies, followed up for a median of 1.44 years. Eighty ICH and 424 ischemic strokes occurred. BGPVS were associated with increasing age, hypertension, previous ischemic stroke, previous ICH, lacunes, cerebral microbleeds, and white matter hyperintensities. CSOPVS showed consistently weaker associations. Prospectively, after adjusting for potential confounders including cerebral microbleeds, increasing BGPVS burden was independently associated with future ischemic stroke (versus 0-10 BGPVS, 11-20 BGPVS: HR 1.19, 95% CI 0.93-1.53; 21+ BGPVS: HR 1.50, 95% CI 1.10-2.06; p = 0.040). Higher BGPVS burden was associated with increased ICH risk in univariable analysis, but not in adjusted analyses. CSOPVS were not significantly associated with either outcome.

DISCUSSION

In patients with ischemic stroke or TIA, increasing BGPVS burden is associated with more severe cerebral small vessel disease and higher ischemic stroke risk. Neither BGPVS nor CSOPVS were independently associated with future ICH.

Semisolid Enteral Nutrients Alter the Pharmacokinetics of Orally Administered Levetiracetam in Rats

Enteral nutrients (ENs) affect the plasma drug concentration of orally co-administered drugs, particularly those of antiepileptic drugs, such as phenytoin and carbamazepine. However, few studies have reported the interactions of levetiracetam (LEV), an upcoming antiepileptic drug, with ENs. In this study we aimed to investigate the pharmacokinetics of LEV in 55 rats after oral co-administration of LEV with liquid or semisolid ENs. Compared with the control group, co-administration with Terumeal ® Soft significantly decreased the plasma LEV concentration at 0.5, 1, and 2 h and area under the plasma concentration-time curve from 0 to 3 h (AUC0→3h) (P < 0.01). However, the AUC0→3h of LEV remained unchanged following the administration of Terumeal ® Soft 2 h after the initial LEV administration. Moreover, co-administration with semisolid Racol® NF delayed the absorption of LEV without decreasing the AUC0→3h, whereas liquid Racol ® NF did not alter LEV pharmacokinetics. Thus, co-administration of LEV with Terumeal® Soft reduced the absorption of LEV from the gastrointestinal tract, which was prevented by administering Terumeal ® Soft 2 h after LEV administration. Semisolid Racol ® NF altered LEV pharmacokinetics without decreasing its gastrointestinal absorption. Our findings suggested that careful monitoring of the plasma LEV levels is necessary when co-administering LEV with Terumeal ® Soft, semisolid Racol ® NF, or any other semisolid ENs, to prevent the inadvertent effects of the interaction between LEV and ENs.

Impact of Cerebral Microbleeds in Stroke Patients with Atrial Fibrillation

OBJECTIVES

Cerebral microbleeds are associated with the risks of ischemic stroke and intracranial hemorrhage, causing clinical dilemmas for antithrombotic treatment decisions. We aimed to evaluate the risks of intracranial hemorrhage and ischemic stroke associated with microbleeds in patients with atrial fibrillation treated with vitamin K antagonists, direct oral anticoagulants, antiplatelets, and combination therapy (i.e. concurrent oral anticoagulant and antiplatelet).

METHODS

We included patients with documented atrial fibrillation from the pooled individual patient data analysis by the Microbleeds International Collaborative Network. Risks of subsequent intracranial hemorrhage and ischemic stroke were compared between patients with and without microbleeds, stratified by antithrombotic use.

RESULTS

A total of 7,839 patients were included. The presence of microbleeds was associated with an increased relative risk of intracranial hemorrhage (adjusted hazard ratio [aHR] = 2.74, 95% confidence interval = 1.76-4.26) and ischemic stroke (aHR = 1.29, 95% confidence interval = 1.04-1.59). For the entire cohort, the absolute incidence of ischemic stroke was higher than intracranial hemorrhage regardless of microbleed burden. However, for the subgroup of patients taking combination of anticoagulant and antiplatelet therapy, the absolute risk of intracranial hemorrhage exceeded that of ischemic stroke in those with 2 to 4 microbleeds (25 vs 12 per 1,000 patient-years) and ≥ 11 microbleeds (94 vs 48 per 1,000 patient-years).

INTERPRETATION

Patients with atrial fibrillation and high burden of microbleeds receiving combination therapy have a tendency of higher rate of intracranial hemorrhage than ischemic stroke, with potential for net harm. Further studies are needed to help optimize stroke preventive strategies in this high-risk group. ANN NEUROL 2023;94:61-74.

Stroke Risk and Antithrombotic Treatment During Follow-up of Patients With Ischemic Stroke and Cortical Superficial Siderosis

BACKGROUND AND OBJECTIVES

In patients with ischemic stroke (IS) or transient ischemic attack (TIA) and cortical superficial siderosis (cSS), there are few data regarding the risk of future cerebrovascular events and also about the benefits and safety of antithrombotic drugs for secondary prevention. We investigated the associations of cSS and stroke risk in patients with recent IS or TIA.

METHODS

We retrospectively analyzed the Microbleeds International Collaborative Network (MICON) database. We selected patients with IS or TIA from cohorts who had MRI-assessed cSS, available data on antithrombotic treatments, recurrent cerebrovascular events (intracranial hemorrhage [ICrH], IS, or any stroke [ICrH or IS]), and mortality. We calculated incidence rates (IRs) and performed univariable and multivariable Cox regression analyses.

RESULTS

Of 12,669 patients (mean age 70.4 ± 12.3 years, 57.3% men), cSS was detected in 273 (2.2%) patients. During a mean follow-up of 24 ± 17 months, IS was more frequent than ICrH in both cSS (IR 57.1 vs 14.6 per 1,000 patient-years) and non-cSS (33.7 vs 6.3 per 1,000 patient-years) groups. Compared with the non-cSS group, cSS was associated with any stroke on multivariable analysis {IR 83 vs 42 per 1,000 patient-years, adjusted hazard ratio [HR] for cSS 1.62 (95% CI: 1.14-2.28; p = 0.006)}. This association was not significant in subgroups of patients treated with antiplatelet drugs (n = 6,554) or with anticoagulants (n = 4,044). Patients with cSS who were treated with both antiplatelet drugs and anticoagulants (n = 1,569) had a higher incidence of ICrH (IR 107.5 vs 4.9 per 1,000 patient-years, adjusted HR 13.26; 95% CI: 2.90-60.63; p = 0.001) and of any stroke (IR 198.8 vs 34.7 per 1,000 patient-years, adjusted HR 5.03; 95% CI: 2.03-12.44; p < 0.001) compared with the non-cSS group.

DISCUSSION

Patients with IS or TIA with cSS are at increased risk of stroke (ICrH or IS) during follow-up; the risk of IS exceeds that of ICrH for patients receiving antiplatelet or anticoagulant treatment alone, but the risk of ICrH exceeds that of IS in patients receiving both treatments. The findings suggest that either antiplatelet or anticoagulant treatment alone should not be avoided in patients with cSS, but combined antithrombotic therapy might be hazardous. Our findings need to be confirmed by randomized clinical trials.

Abstract 3: Cerebral Small Vessel Disease Burden For Bleeding Risk During Antithrombotic Therapy -BAT2-

Background: Cerebral small vessel disease (SVD) has received attention as a risk stratification tool for antithrombotic-related intracranial hemorrhage but may also be a predictor for bleeding in other organs.

Purpose: To determine the excess risk of antithrombotic-related bleeding due to cerebral SVD burden.

Methods: Patients with cerebrovascular or cardiovascular diseases taking oral antithrombotic agents were prospectively enrolled from 52 hospitals across Japan between 2016 and 2019. Multimodal brain MRI was acquired at baseline for all patients under prespecified conditions. All MRI examinations were interpreted by a central diagnostic radiology committee for cerebral microbleeds, lacunes, white matter hyperintensities, and enlarged basal ganglia perivascular spaces, for calculation of a total SVD score (range 0-4). The primary outcome was major bleeding during 2-year follow-up. Secondary outcomes included bleeding in each site and ischemic events. Event risks according to SVD score were estimated with multivariable Cox proportional hazards models.

Results: Of the analyzed 5250 patients (1736 women; median age, 73 years; 9933 patient-years follow-up), antiplatelets and anticoagulants were administered at baseline in 3948 and 1565, respectively. Median of the total SVD score was 2 (IQR 1-3). As SVD score increased, advanced age, hypertension, anemia, and chronic kidney disease were more prevalent (P<0.001 for each). A unit increase of SVD score was associated with a higher risk of major bleeding (adjusted hazard ratio [HR] 1.55, 95% confidence interval [CI] 1.29-1.85) and intracranial hemorrhage (adjusted HR 1.61, 95% CI 1.28-2.03). With SVD score 4 compared to score 0, extracranial major bleeding (adjusted HR 3.37, 95% CI 1.12-10.15) and gastrointestinal bleeding (adjusted HR 2.54, 95% CI 1.02-6.35) were also significantly increased. A higher SVD score was associated with a mild but significant elevation of ischemic event risk (adjusted HR per unit increase 1.17, 95% CI 1.06-1.29).

Conclusions: The total SVD score was predictive for intracranial hemorrhage and probably for extracranial bleeding, suggesting a broader clinical relevance of cerebral SVD as a marker for safe implementation of antithrombotic therapy.

Hypertension, cerebral Amyloid, aGe Associated Known neuroimaging markers of cerebral small vessel disease Undertaken with stroke REgistry (HAGAKURE) prospective cohort study: Baseline characteristics and association of cerebral small vessel disease with prognosis in an ischemic stroke cohort

Introduction

Cerebral small vessel disease (SVD) is one of the leading causes of stroke; each neuroimaging marker of SVD is correlated with vascular risk factors and associated with poor prognosis after stroke. However, longitudinal studies investigating the association between comprehensive SVD burden scoring system, "total SVD score" - which encompasses the established neuroimaging markers of lacunae, cerebral microbleeds (CMBs), white matter hyperintensities (WMH) including periventricular hyperintensities, and perivascular spaces in basal ganglia- and clinical outcomes are limited. The aim of this study is to determine the association between SVD burden and long-term prognosis in patients with ischemic stroke.

Methods and design

This prospective, single-center, observational study enrolled patients with acute ischemic stroke, including cerebral infarction and transient ischemic attack. Magnetic resonance imaging scans were performed, and then total SVD score (range, 0-4) was calculated. We recorded baseline characteristics and evaluated the relationships of long-term outcomes to SVD neuroimaging markers and total SVD score. Stroke recurrence was thought as primary outcome. Hazard ratios (HRs) of events during follow-up were calculated using Cox proportional hazards modeling with adjustments for age, sex, hypertension, dyslipidemia, diabetes mellitus, atrial fibrillation, and smoking. Cumulative event rates were estimated using the Kaplan-Meier method.

Results

Consecutive 564 acute ischemic stroke patients were enrolled according to inclusion and exclusion criteria. A total of 467 participants with first-ever ischemic stroke were analyzed (median age 75.0 [interquartile range, 64.0-83.0] years, 59.3% male). Total SVD score was 0 point in 47 individuals (12.0%), 1 point in 83 (21.2%), 2 points in 103 (26.3%), 3 points in 85 (21.7%), and 4 points in 73 (18.7%). Twenty-eight recurrent stroke events were identified during follow-up. Total SVD score ≥ 2, presence of CMBs, and moderate-to-severe WMH were associated with increased risk of recurrent stroke events (HR 9.31, 95% confidence interval [CI] 2.33-64.23; HR 2.81, 95% CI 1.08-7.30; HR 2.90, 95% CI 1.22-6.88, respectively).

Conclusion

The accumulation of SVD biomarkers as determined by total SVD score offered a reliable predictor of stroke recurrence. This study established a firm understanding of SVD prognosis in clinical settings.

Increased Cerebral Small Vessel Disease Burden With Renal Dysfunction and Albuminuria in Patients Taking Antithrombotic Agents: The Bleeding With Antithrombotic Therapy 2

Background

The aim of this study was to determine the associations of cerebral small vessel disease (SVD) burden with renal dysfunction and albuminuria in patients taking oral antithrombotic agents.

Methods and Results

Patients who newly started or continued taking oral antiplatelets or anticoagulants were enrolled in a prospective, multicenter, observational study. Obligatorily acquired multimodal magnetic resonance imaging at registration with prespecified imaging conditions was assessed for cerebral microbleeds, white matter hyperintensities, enlarged basal ganglia perivascular spaces, or lacunes, and an ordinal SVD score was calculated (range, 0–4). Multivariable adjusting covariates were age, sex, hypertension, diabetes, dyslipidemia, current smoking, drinking, and estimated glomerular filtration rate (eGFR). Of 5324 patients (1762 women; median age, 73 years), 4797 (90.1%) patients were taking oral antithrombotic agents for secondary stroke prevention. Cerebral microbleeds were present in 32.7%, confluent white matter hyperintensities in 51.8%, extensive basal ganglia perivascular spaces in 38.9%, and lacunes in 59.4%. Median SVD score was 2. Compared with eGFR category G1 (eGFR ≥90 mL/min per 1.73 m²), adjusted odds ratios for SVD score increment were 1.63 (95% CI, 1.11–2.39) at category G4 (eGFR 15–<30 mL/min per 1.73 m²) and 2.05 (95% CI, 1.33–3.16) at G5 (eGFR <15 mL/min per 1.73 m²). Corresponding odds ratios relative to urinary albumin‐to‐creatinine ratio (ACR) category A1 (ACR <30 mg/g) were 1.29 (95% CI, 1.12–1.49) for category A2 (ACR 30–<300 mg/g) and 1.37 (95% CI, 1.05–1.77) for A3 (ACR ≥300 mg/g). When combined eGFR and ACR categories were assessed, risks for SVD score increment generally increased as eGFR decreased and ACR increased.

Conclusions

Both reduced eGFR and albuminuria were independently associated with increased cerebral SVD burden in patients requiring oral antithrombotic medication mainly for secondary stroke prevention.

Registration

URL: https://www.clinicaltrials.gov; Unique identifier: NCT01581502; URL: https://www.umin.ac.jp/ctr; Unique identifier: UMIN000023669.

Development of imaging-based risk scores for prediction of intracranial haemorrhage and ischaemic stroke in patients taking antithrombotic therapy after ischaemic stroke or transient ischaemic attack: a pooled analysis of individual patient data from cohort studies

BACKGROUND

Balancing the risks of recurrent ischaemic stroke and intracranial haemorrhage is important for patients treated with antithrombotic therapy after ischaemic stroke or transient ischaemic attack. However, existing predictive models offer insufficient performance, particularly for assessing the risk of intracranial haemorrhage. We aimed to develop new risk scores incorporating clinical variables and cerebral microbleeds, an MRI biomarker of intracranial haemorrhage and ischaemic stroke risk.

METHODS

We did a pooled analysis of individual-patient data from the Microbleeds International Collaborative Network (MICON), which includes 38 hospital-based prospective cohort studies from 18 countries. All studies recruited participants with previous ischaemic stroke or transient ischaemic attack, acquired baseline MRI allowing quantification of cerebral microbleeds, and followed-up participants for ischaemic stroke and intracranial haemorrhage. Participants not taking antithrombotic drugs were excluded. We developed Cox regression models to predict the 5-year risks of intracranial haemorrhage and ischaemic stroke, selecting candidate predictors on biological relevance and simplifying models using backward elimination. We derived integer risk scores for clinical use. We assessed model performance in internal validation, adjusted for optimism using bootstrapping. The study is registered on PROSPERO, CRD42016036602.

FINDINGS

The included studies recruited participants between Aug 28, 2001, and Feb 4, 2018. 15 766 participants had follow-up for intracranial haemorrhage, and 15 784 for ischaemic stroke. Over a median follow-up of 2 years, 184 intracranial haemorrhages and 1048 ischaemic strokes were reported. The risk models we developed included cerebral microbleed burden and simple clinical variables. Optimism-adjusted c indices were 0·73 (95% CI 0·69-0·77) with a calibration slope of 0·94 (0·81-1·06) for the intracranial haemorrhage model and 0·63 (0·62-0·65) with a calibration slope of 0·97 (0·87-1·07) for the ischaemic stroke model. There was good agreement between predicted and observed risk for both models.

INTERPRETATION

The MICON risk scores, incorporating clinical variables and cerebral microbleeds, offer predictive value for the long-term risks of intracranial haemorrhage and ischaemic stroke in patients prescribed antithrombotic therapy for secondary stroke prevention; external validation is warranted.

FUNDING

British Heart Foundation and Stroke Association.

The role of B cells and IgG in aortic dissection

Background

Aortic dissection (AD) is one of the destructive and fatal aortic diseases, for which molecular pathogenesis is largely unknown. Recent studies have highlighted the importance of inflammatory response in AD. We and others reported that B cells and immunoglobulins participate in pathogenesis of abdominal aortic aneurysm, another form of aortic destructive disease, by promoting inflammatory response. It is not known whether and how B cells participate in AD pathogenesis.

Methods and results

Immunohistochemical staining of human AD tissue revealed that B cells were clustered together with T cells, macrophages and neutrophils at the entry site of AD with medial disruption. B cell cluster was also observed at the site of medial disruption in mouse model of AD that was induced by continuous infusion of beta-aminopropionitrile and angiotensin II (BAPN+AngII). In muMT mouse, which is deficient for B cells and immunoglobulins due to genetic deletion of immunoglobulin heavy chain, BAPN+AngII induced significantly less severe AD compared to that in wild type. Depositions of IgG and fibrinogen, one of the endogenous antigen for natural IgG, were observed after BAPN+AngII infusion before and after AD development in wild type mice. Deposition of fibrinogen was also observed in mMT mice after BAPN+AngII infusion. The rate of aortic rupture and sudden death was approximately 42% in wild type mice, while that in muMT mouse was 12% (P&lt;0.05). Administration of mouse normal polyclonal IgG to muMT mice resulted in dramatic increase in aortic rupture and sudden death, starting at day 7 of BAPN+AngII infusion, and reaching 69% of rupture rate, indicating the critical role of IgG in AD.

Conclusion

These findings demonstrated B cells and IgG are critically involved in the destructive inflammation of AD pathogenesis. Further, the deposition of fibrinogen, one of the targets of natural IgG, precedes the development of AD. Our findings may provide the conceptual foundation of the diagnostic strategy for on-going tissue destruction and for the therapeutic opportunities to intervene the progressive tissue destruction in AD.

Funding Acknowledgement

Type of funding source: Public grant(s) – National budget only. Main funding source(s): The Japan Society for the Promotion of Science

Proportion of intracerebral haemorrhage due to cerebral amyloid angiopathy in the East and West: Comparison between single hospital centres in Japan and the United Kingdom

PURPOSE

We investigated whether the proportion of intracerebral haemorrhage (ICH) due to cerebral amyloid angiopathy (CAA) differs between patients admitted to hospitals in the East and the West.

METHODS

This international cross-sectional study included consecutive spontaneous ICH patients admitted to one stroke centre in the United Kingdom (Western centre origin) and one in Japan (Eastern centre origin) during the same period. We classified spontaneous ICH into "CAA-related" or "other" using the Edinburgh CT-based diagnostic criteria. We used multivariable logistic regression analyses to assess the relationship between CAA-related ICH and geographical location or ethnicity (White vs. East Asian or other ethnicities). Sensitivity analyses were performed using the modified Boston MRI-based diagnostic criteria for CAA-related ICH.

RESULTS

Of 433 patients (median age, 72 years; Western centre origin, 55%), 15% were classified as CAA-related ICH. In the multivariable logistic regression model, Eastern centre and ethnicity had a lower proportion of CAA-related ICH (odds ratio [OR] vs Western centre origin 0.55, 95%CI 0.31-0.98; OR [vs. White] 0.47, 95%CI 0.25-0.87); these findings remained robust in sensitivity analyses. The estimated incidence of "other" (non-CAA) ICH (attributed to hypertensive arteriopathy) was 2.5-fold higher in East Asian populations.

CONCLUSIONS

The proportion CAA-related ICH is lower in an Eastern compared to a Western hospital ICH population; this might be explained by a higher incidence of ICH related to hypertensive arteriopathy in East Asian populations, suggesting that optimal ICH prevention strategies might differ between the East and West.

Association between Pericytes in Intraplaque Neovessels and Magnetic Resonance Angiography Findings

(1) Background: Pericytes are involved in intraplaque neovascularization of advanced and complicated atherosclerotic lesions. However, the role of pericytes in human carotid plaques is unclear. An unstable carotid plaque that shows high-intensity signals on time-of-flight (TOF) magnetic resonance angiography (MRA) is often a cause of ischemic stroke. The aim of the present study is to examine the relationship between the pericytes in intraplaque neovessels and MRA findings. (2) Methods: A total of 46 patients with 49 carotid artery stenoses who underwent carotid endarterectomy at our hospitals were enrolled. The patients with carotid plaques that were histopathologically evaluated were retrospectively analyzed. Intraplaque hemorrhage was evaluated using glycophorin A staining, and intraplaque neovessels were evaluated using CD34 (Cluster of differentiation) stain as an endothelial cell marker or NG2 (Neuron-glial antigen 2) and CD146 stains as pericyte markers. Additionally, the relationships between the TOF-MRA findings and the carotid plaque pathologies were evaluated. (3) Results: Of the 49 stenoses, 28 had high-intensity signals (TOF-HIS group) and 21 had iso-intensity signals (TOF-IIS group) on TOF-MRA. The density of the CD34-positive neovessels was equivalent in both groups. However, the NG2- and CD146-positive neovessels had significantly higher densities in the TOF-HIS group than in the TOF-IIS group. (4) Conclusion: The presence of a high-intensity signal on TOF-MRA in carotid plaques was associated with intraplaque hemorrhage and few pericytes in intraplaque neovessels. These findings may contribute to the development of new therapeutic strategies focusing on pericytes.

Total small vessel disease score and cerebro-cardiovascular events in healthy adults: The Kashima scan study

BACKGROUND AND AIMS

We explored the association between the total small vessel disease score obtained from baseline magnetic resonance imaging and subsequent cerebro-cardiovascular events in neurologically healthy Japanese adults.

METHODS

The presence of small vessel disease features, including lacunae, cerebral microbleeds, white matter changes, and basal ganglia perivascular spaces on magnetic resonance imaging, was summed to obtain a "total small vessel disease score" (range, 0-4). After excluding participants with previous stroke or ischemic heart disease, intracranial artery stenosis (≥50%), or cerebral aneurysm (≥4 mm), a total of 1349 participants (mean age, 57.7 years; range, 22.8-85.0 years; 46.9% male) were classified into three groups by total small vessel disease score: 0 (n = 984), 1 (n = 269), and ≥2 (n = 96). Cerebro-cardiovascular events (i.e., any stroke, transient ischemic attack, ischemic heart disease, acute heart failure, and aortic dissection) were defined as the primary end point. The hazard ratio (HR) of events during follow-up was calculated using Cox proportional hazards modeling with adjustments for age, sex, hypertension, diabetes mellitus, and smoking. Cumulative event-free rates were estimated using the Kaplan-Meier method.

RESULTS

During follow-up (mean, 6.7 years), 35 cerebro-cardiovascular (16 cerebrovascular) events were identified. Higher small vessel disease score was associated with increased risk of cerebro-cardiovascular events (HR per unit increase, 2.17; 95% confidence interval, 1.36-3.46; P = 0.001). Events were more frequent among participants with higher score (P < 0.001, log-rank test).

CONCLUSIONS

This study offered additional evidence for the clinical relevance of total small vessel disease score, suggesting the score as a promising tool to predict the risk of subsequent vascular events even in healthy populations.

Abstract TP330: Proportion of Intracerebral Haemorrhage Due to Cerebral Amyloid Angiopathy in the East and West

Objectives: We investigated whether the proportion of intracerebral haemorrhage (ICH) due to cerebral amyloid angiopathy (CAA) differs between patients of Eastern and Western origin.

Methods: This is a retrospective international cross-sectional study of consecutive first-ever spontaneous ICH patients (including patients with surgical intervention) admitted to one stroke centre in the United Kingdom (Western centre origin) and one in Japan (Eastern centre origin) during the same period. We classified spontaneous ICH into “CAA-related ICH” defined by the Edinburgh CT diagnostic criteria, and “other ICH”. We used multivariable logistic regression analyses to assess the relationship between CAA-ICH and geographical location (Western or Eastern centre origin) or ethnicity (Western [reference], East Asian, or other) with adjustment for confounders.

Results: Of 334 patients (median age, 71 years; male, 54%; Western centre origin, 58%), 15% were classified as CAA-ICH, and 85% were defined as other ICH. In multivariable logistic regression analysis, Eastern centre and ethnicity had a lower proportion of CAA-ICH (odds ratio [OR] vs Western centre origin 0.47, 95%CI 0.23-0.98; OR [vs. white] 0.41, 95%CI 0.20-0.97, respectively).The estimated incidence of CAA-related ICH in East Asian was similar to that in White populations, but the rate of other ICH was 2.5-fold higher in East Asian populations. Sensitivity analyses using the modified Boston criteria for diagnosis of CAA-related ICH showed similar results.

Conclusions: The proportion CAA-ICH is lower in an Eastern compared to a Western population; this appears to be explained by a higher incidence of ICH due to hypertensive (deep perforator) arteriopathy in East Asian populations.

Interaction between phenytoin and enteral nutrients and its influence on gastrointestinal absorption

The gastrointestinal absorption of phenytoin (PHT), an antiepileptic drug, is often affected by its interaction with co-administered enteral nutrients through a nasogastric (NG) tube, resulting in decreased plasma PHT concentration. In this study, we measured the recovery rate (%) of PHT (Aleviatin^® powder) passed through an NG tube when co-administered with distilled water or enteral nutrients (F2α^®, Racol^® NF, Ensure Liquid^® and Renalen^® LP). We also measured plasma PHT levels in rats, after oral co-administration of PHT with enteral nutrients. We demonstrate that PHT recovery rate was close to 100 % in all cases after passage through the NG tube. In the rat study, the AUC_0→∞ of PHT concentration after oral administration significantly decreased when it was co-administered with F2α^® and Racol^® NF compared to distilled water. However, the AUC_0→∞ of PHT was unchanged when co-administered with F2α^® 2 h after initial PHT administration. We therefore conclude that the co-administration of PHT with F2α^® and Racol^® NF caused a reduction in the absorption of PHT from the gastrointestinal tract to the blood, without adsorption to the NG tube. The administration of enteral nutrients 2 h after PHT is one clear way to prevent a decrease in plasma PHT concentration.

Risk factors increasing blood pressure in Japanese colorectal cancer patients treated with bevacizumab

Bevacizumab has been reported to increase blood pressure. However, the factors, including patient characteristics and laboratory data contributing to this side effect remain unclear. Therefore, we investigated the relationships between increased blood pressure and bevacizumab administration, patient characteristics, and laboratory data. Between April 2007 and January 2018, factor analysis was retrospectively conducted by monitoring increases in blood pressure, the status of bevacizumab administration, patient characteristics, and laboratory data before the first administration in Japanese patients with colorectal cancer who satisfied the criteria for this study. Sixty-seven patients were included, 34 of whom (50.7%) had an increase in blood pressure after bevacizumab administration. On univariate analysis, liver metastasis, antihypertensive drug use, systolic blood pressure at rest before the first bevacizumab administration, body mass index, creatinine, and blood platelet count were significantly different between the two groups. Multivariate analysis was conducted using increased blood pressure as an objective variable and the factors extracted by the univariate analysis as explanatory variables. The results suggested that liver metastasis, antihypertensive drugs, systolic blood pressure at rest before the first bevacizumab administration, and creatinine were associated with the increase in blood pressure. Furthermore, a log-rank test performed based on Kaplan-Meier curves demonstrated that liver metastasis in patients not taking antihypertensive drugs and antihypertensive drug use in patients without liver metastasis were significantly associated with increased blood pressure. Additionally, liver metastasis in patients with antihypertensive drug use was significantly associated with increased blood pressure. Our findings suggest that liver metastasis and antihypertensive drug use, which was previously reported, are risk factors for increased blood pressure.

Significance of simulated conventional images on dual energy CT after endovascular treatment for ischemic stroke

BACKGROUND AND PURPOSE

CT scans often reveal post-interventional cerebral hyperdensities (PCHDs) immediately after intra-arterial thrombectomy (IAT) for ischemic stroke. Dual energy CT (DE-CT) can indicate whether PCHDs are caused by hemorrhage or iodinated contrast. Hyperdense lesions, detected on DE-CT with the use of iodinated contrast, could be associated with delayed hemorrhagic transformation and poor outcome. However, the quantitative indicators in DE-CT for predicting delayed hemorrhagic transformation remain unclear. We assessed such indicators for predicting delayed hemorrhagic transformation.

MATERIAL AND METHODS

We retrospectively analyzed 52 consecutive acute ischemic stroke patients who underwent IAT. Simulated conventional CT (sCCT) images were obtained immediately after a DE-CT scan. Virtual, unenhanced, non-contrast (VNC) imaging was performed after reconstruction. Hounsfield units (HU) of the infarct areas observed on the sCCT were measured. The association of HU on sCCT with hemorrhage on VNC and delayed parenchymal hemorrhage (PH) was evaluated.

RESULTS

The HU of sCCT with hemorrhage on VNC was significantly higher than without it (377.9±385 HU vs 83.5±37.9 HU; P<0.0001). The cut-off index was 80 HU, which displayed 100% sensitivity, 63.8% specificity, 22.3% positive predictive value, and 100% negative predictive value (P=0.0001, area under the curve (AUC)=0.89). The HU with delayed PH was substantially higher than without it (250.8±382.2 HU vs 93.7±64.8 HU; P=0.01). The cut-off index was 78 HU, which showed 100% sensitivity, 61% specificity, 25% positive predictive value, and 100% negative predictive value (P=0.049, AUC=0.76).

CONCLUSION

sCCT images on DE-CT are useful for excluding intracerebral hemorrhage and delayed PH.

Improvement Of Frontal Lobe Dysfunction And White Matter Integrity By rTMS In Treatment-Resistant Depression

AIM

The impairment experienced by many individuals with depression is closely related to the cognitive symptoms of the disorder. Repetitive transcranial magnetic stimulation (rTMS) is a noninvasive brain stimulation method providing a promising technique for improving cognitive symptoms in treatment-resistant depression (TRD). In the present study, we investigated whether a relationship exists between improvements in frontal lobe dysfunction induced by rTMS and improvement of white matter integrity revealed by diffusion tensor imaging (DTI) in TRD patients receiving rTMS treatment.

METHODS

A total of 12 patients with TRD were enrolled in a high-frequency (10 Hz) rTMS study (August 2013-January 2019). Frontal lobe function and depressive symptoms were assessed at baseline and at the endpoint of rTMS treatment. Fractional anisotropy (FA), as a measure of white matter integrity obtained from DTI, was investigated using a region-of-interest (ROI) approach.

RESULTS

rTMS treatment significantly improved depressive symptom scores and some subscales of frontal lobe dysfunction. Category scores in the Word Fluency Test and scores on part 3 of the Color Stroop Test were improved independently of the improvement of depressive symptoms. In the ROI analysis, none of the FA increases in any region were correlated with improvement of any frontal lobe function (n = 12).

CONCLUSION

Although rTMS resulted in partial improvement of frontal lobe dysfunction as well as white matter integrity, we found no correlation between improved frontal lobe dysfunction and improved white matter integrity in TRD patients.

Total Small Vessel Disease Score in Neurologically Healthy Japanese Adults in the Kashima Scan Study

Objective We explored the association between the total small vessel disease (SVD) score obtained with magnetic resonance imaging and risk factors and outcomes in the Japanese population. Methods The presence of SVD features, including lacunes, cerebral microbleeds, white matter changes, and basal ganglia perivascular spaces on MRI, was summed to obtain a "total SVD score" (range 0-4). Ordinal and multinomial logistic regression analyses were performed to investigate the association of higher total SVD scores with vascular risk factors, the Mini-Mental State Examination (MMSE) score, and cerebral atrophy. Results We included 1,451 neurologically healthy adults (mean age, 57.1 years; 47% male). A multivariate ordinal logistic regression analysis showed that the total SVD score was associated with aging, hypertension, blood pressure (BP), diabetes mellitus, MMSE score, and deep cerebral atrophy, but the equal slopes assumption between scores did not hold. A multivariate multinomial logistic regression analysis (total SVD score 0=reference) showed that aging, hypertension, and BP were positively associated with scores of 1, 2, or ≥3. These effects, presented as odds ratios (ORs), increased as the score increased and were strongest with a score of ≥3 [aging (per 10-year increment), OR 4.00, 95% confidence interval (CI) 2.47-6.46; hypertension, OR 5.68, 95% CI 2.52-12.80; systolic BP (per standard deviation increase), OR 1.96, 95% CI 1.41-2.74, respectively]. Diabetes mellitus and deep cerebral atrophy tended to be associated with the SVD scores. The MMSE score showed no consistent associations. Conclusion The total SVD score may be a promising tool for indexing SVD, even in the Japanese population.

Molecular species of prostaglandins involved in modulating luteinising hormone pulses of female rats under infectious stress conditions

Mammalian reproductive function is controlled by the hypothalamic-pituitary-gonadal (HPG) axis, which is suppressed under infectious stress conditions. By analysing the pulsatility of luteinising hormone (LH), we have previously demonstrated that prostaglandins (PGs) in the central nervous system mediate infectious stress to suppress the activity of the HPG axis. The present study aimed to characterise the types of PGs responsible for suppression of the HPG axis. We focused on three major types of PGs: PGE₂ , PGD₂ and PGF_2α . We used female rats overiectomised bilaterally 1 week before the experiments. Lipopolysaccharide (100 μg kg^-1 ) suppressed LH pulses at the same time as enhancing the concentration of all three PGs in the cerebrospinal fluid, which was restored by indomethacin (10 mg kg^-1 ). Subsequently, we observed LH pulsatility after a single injection of each PG and after co-injection of PGE₂ with PGF_2α into the third cerebral ventricle. A single injection of PGE₂ dose-dependently induced a transient increase in mean LH concentration and LH pulse amplitude, and PGD₂ significantly increased the amplitude of LH pulses, wereas PGF_2α did not affect LH pulsatility. On the other hand, co-injection of PGE₂ and PGF_2α induced a significant suppression of both the frequency and amplitude of LH pulses. These results suggest that PGE₂ and PGF_2α can represent two of the mediators that suppress the HPG axis in situations of infectious stress. Moreover, the results imply that there are two contradictory effects of PGE₂ on LH pulsatility: (i) enhancive when working alone and (ii) suppressive when working together with PGF_2α .

Pretreatment of Crude Pancreatic Islets with Mitomycin C (Mmc) Prolongs Islet Graft Survival in a Xenogeneic Rat-To-Mouse Model

In this study, we examined the effect of mitomycin C (MMC) treatment on graft survival and evaluated its efficacy in immunomodulation of islet graft for transplantation. Male WS rats were used as islet donors and streptozotocin-induced diabetic C57BL/6 mice as recipients. The isolated islets were treated with MMC at concentrations of 0, 0.1, 1, 3.2, 10, 32, 100, 320, and 1000 μg/mL for 30 min, and were cultured for 20 h. Then, 300–400 islets were transplanted into the renal subcapsular space of diabetic mice. Significant prolongation of graft survival was obtained when the islets were treated with MMC at a concentration of 10, 32, or 100 μg/mL (MST 23 ± 7.4, 17.5 ± 5.4, 29.6 ± 9.7 days: p < 0.003, p < 0.012, p < 0.001, respectively, vs. 12.3 ± 2.7 days for culturing alone). Islets treated with MMC at a concentration of 320 μg/mL or more failed to restore normoglycemia in the diabetic recipient mice after transplantation. Viability of islets incubated with doses up to 100 μg/mL, assessed under the confocal microscope after propidium iodide and Hoechst 33342 staining, was maintained well comparable to that of freshly isolated islets, while those treated at 320 μg/mL was significantly decreased. Thus, a therapeutic window for MMC efficacy was found at concentrations from 10 μg/mL to 100 μg/mL. This modality is simple and effective and underlying molecular mechanisms need to be determined in the future.

Thrombolysis-related Multiple Lobar Hemorrhaging in Cerebral Amyloid Angiopathy with Extensive Strictly Lobar Cerebral Microbleeding

A hemi-paralyzed 86-year-old man was diagnosed with ischemic stroke and underwent thrombolysis. Pre-thrombolysis brain magnetic resonance imaging revealed extensive strictly lobar cerebral microbleeding (CMB). Post-thrombolytic computed tomography revealed asymptomatic multiple intracerebral hemorrhaging (ICH). His age, CMB topography, and decreased cerebral spinal fluid amyloid-β 40 and 42 levels were compatible with a diagnosis of cerebral amyloid angiopathy (CAA). There is no consensus on the safety of thrombolysis for acute stroke patients with CAA. Patients with CAA might have a higher incidence of thrombolysis-related ICH than those without CAA.

Magnetic Resonance (MR) Imaging Assessment for Glossopharyngeal Neuralgia: Value of Three-Dimensional T2-Reversed MR Imaging (3D-T2R) in Conjunction with Other Modes of 3D MR Imaging

Background

To retrospectively examine the usefulness of gray-scale reversal imaging of T2-weighted images (3D-T2R) in conjunction with other modes of 3D MRI for preoperative assessments in patients with glossopharyngeal neuralgia (GPN) due to neurovascular compression.

Material/Methods

Imaging findings on 3D-T2R, constructive interference in steady state (CISS), and MRA were analyzed with reference to operative charts in 10 patients with GPN.

Results

Offending vessels were associated with the posterior inferior cerebellar artery (PICA) in 9 of 10 patients (90%). Eight of the 10 patients (80%) had offending vessels located at the supraolivary fossette. Of those eight patients, six (75%) had a shift of the ipsilateral vertebral artery to the affected side. Five (42%) and seven (48%) contact points were associated with the root entry/exit zone and the peripheral nerve system segment, respectively. In six of nine contact points (67%), 3D-T2R demonstrated the pathomorphological features at the contact points better than CISS.

Conclusions

The offending vessels were mostly associated with posterior inferior cerebellar arteries, were frequently located at the supraolivary fossette, and had attachments at the root entry/exit zone and at the peripheral segment of the glossopharyngeal nerve, which was well demonstrated on 3D-T2R.

Radiological imaging features of glioblastoma with oligodendroglioma component: a comparison with conventional glioblastoma

Background

Glioblastoma with oligodendroglioma component (GBMO) is a subtype of conventional glioblastoma (cGBM), which is categorized as WHO grade IV. GBMO can be histopathologically distinguished from cGBM and the prognosis of GBMO is better than that of cGBM. However, no systematic review of GBMO imaging findings has been published to date.

Purpose

To clarify the radiological imaging features of GBMO compared with those of cGBM.

Material and Methods

The participants were 15 patients with GBMO and 32 patients with cGBM as a control group, all of whom were histopathologically diagnosed. A radiologist retrospectively reviewed the imaging findings of both computed tomography (CT) and magnetic resonance imaging (MRI) for density, signal intensity, contrast medium enhancement (CE), cortical swelling, and cortical swelling without CE. We statistically analyzed the imaging findings by Chi-squared test.

Results

Cortical swelling without CE in GBMO was significantly greater than that in cGBM (P = 0.004). Non-CE and heterogeneous solid enhancement were observed significantly more often in GBMO (P = 0.004). No other findings were significant.

Conclusion

There was significant difference in the findings of the CE, which exhibited solid heterogeneous enhancement in GBMO. Cortical swelling without CE can be considered significantly characteristic of GBMO.

Carotid artery stenosis with a high-intensity signal plaque on time-of-flight magnetic resonance angiography and association with evidence of intraplaque hypoxia

OBJECTIVE

Hypoxia induces angiogenesis and plays a major role in the progression of carotid plaques. During carotid intervention, plaques with high-intensity signals on time-of-flight (TOF) magnetic resonance angiography (MRA) often cause ischemic stroke and embolic complications. However, the role of intraplaque hypoxia before carotid endarterectomy (CEA) and carotid artery stenting is not presently understood. In this study the authors aimed to investigate the relationship between intraplaque hypoxia and MRA findings.

METHODS

Nineteen consecutive patients with 20 carotid artery stenoses who underwent CEA at Saga University Hospital between August 2008 and December 2014 were enrolled in the study. The expressions of hypoxia-inducible transcription factor-1α (HIF-1α) and vascular endothelial growth factor (VEGF) were analyzed by immunohistochemical analysis. In addition, the relationship between the findings on TOF MRA and pathology for the carotid plaques was analyzed.

RESULTS

High-intensity plaques on TOF MRA showed higher expression levels of HIF-1α (p = 0.015) and VEGF (p = 0.007) compared with isointensity plaques. The rate of intraplaque hemorrhage (IPH) on TOF MRA was also significantly higher in the high-intensity plaques than in the isointensity plaques (p = 0.024). Finally, the mean number of neovessels was significantly higher in those without plaque hemorrhage than in those with plaque hemorrhage (p = 0.010).

CONCLUSIONS

Plaques with high-intensity signals on TOF MRA were associated with IPH and evidence of intraplaque hypoxia. This fact may represent an opportunity to establish novel therapeutic agents targeting intraplaque hypoxia.

Arterial Spin-labeling in Central Nervous System Infection

Purpose:

To investigate the characteristics of arterial spin-labeling magnetic resonance imaging (ASL-MRI) in central nervous system (CNS) infection.

Methods:

Thirty-two patients with CNS infections underwent a pulsed ASL-MRI. The findings on ASL-MRI were retrospectively assessed for the pathogens as well as each of the following four pathology classified based on conventional MRI findings: non-purulent parenchymal involvement, meningeal involvement, abscess formation, and ventricular involvement.

Results:

Among the 17 patients with non-purulent parenchymal involvement, ASL-MRI revealed high perfusion in 8 patients (47%) and low perfusion 1 patient (6%). Especially, four of five patients (80%) with definite or suspected herpes simplex virus (HSV) infection showed high perfusion on ASL-MRI. Seventeen of 22 patients (77%) with meningeal involvement showed high perfusion along the cerebral sulci irrespective of the pathogens. Meanwhile, 4 of 16 lesions (25%) with abscess formation showed low perfusion and one of six patients (17%) with ventricular involvement had high perfusion.

Conclusions:

The characteristics of ASL-MRI in CNS infections were clearly delineated. ASL-MRI could be helpful for monitoring the brain function in CNS infections noninvasively.

Arterial spin-labeling MR imaging of cerebral hemorrhages

INTRODUCTION

The purpose of this study is to identify the characteristics of brain perfusion measured by arterial spin-labeling magnetic resonance imaging (ASL-MRI) in cerebral hemorrhages.

METHODS

Brain blood flow values (CBF-ASL values) for cerebral and cerebellar hemispheres and segmented cerebral regions were measured by ASL-MRI in 19 putaminal hemorrhage patients and 20 thalamic hemorrhage patients in acute or subacute stages. We assessed the lateralities of CBF-ASL values and the relationships between CBF-ASL values and other imaging findings and clinical manifestations.

RESULTS

Both the 19 putaminal hemorrhage patients and the 20 thalamic hemorrhage patients had significantly low CBF-ASL values of the contralateral cerebellum in subacute stage, suggesting that ASL-MRI might delineate crossed cerebellar diaschisis (CCD). Ipsilateral low CBF-ASL values were observed in frontal lobes and thalami with a putaminal hemorrhage and lentiform nuclei, temporal lobes, and parietal lobes with a thalamic hemorrhage, suggesting that ASL-MRI showed the ipsilateral cerebral diaschisis (ICD). In the putaminal hemorrhage patients, the hematoma volume negatively affected both the bilateral cerebellar and cerebral hemispheric CBF-ASL values. In the thalamic hemorrhage patients, a concomitant intraventricular hemorrhage caused low cerebral hemispheric CBF-ASL values.

CONCLUSION

The use of ASL-MRI is sensitive to the perfusion abnormalities and could thus be helpful to estimate functional abnormalities in cerebral hemorrhage patients.

Noninvasive method for mapping CVR in moyamoya disease using ASL-MRI

PURPOSE

To project a noninvasive method for mapping cerebrovascular reserve (CVR) in moyamoya disease (MMD) using ASL-MRI.

METHODS

16 MMD patients underwent cerebral blood flow (CBF) examinations by standard ASL-MRI, pulse-wave-synchronized ASL-MRI (pulsy ASL-MRI) which tagged the arterial blood coincident with a peak of a pulse wave, and single photon emission computed tomography (SPECT) imagings with iodine-123-N-isopropyl-p-iodoamphetamine in the resting (rest-IMP) and after acetazolamide challenge (ACZ-IMP). Hemispheric 32-sided cerebral blood flow (CBF) values were measured with normalized CBF maps created from standard ASL-MRI (standard-ASL value), pulsy ASL-MRI (pulsy-ASL value), rest-IMP (rest-IMP value), and ACZ-IMP (ACZ-IMP value). CVR based on rest-IMP and ACZ-IMP values (IMP-CVR) was calculated. ASL-CVR was also calculated on the basis of corrected standard-ASL values and pulsy-ASL values, which were adjusted to the ACZ-IMP values and rest-IMP values, respectively, by the least-squares method. We assessed the relationships between rest-IMP values and pulsy-ASL values, ACZ-IMP values and standard-ASL values, and IMP-CVR and ASL-CVR.

RESULTS

Significant relationships were observed between rest-IMP values and pulsy-ASL values (correlation coefficient (r=0.557, p<0.01)), ACZ-IMP values and standard-ASL values (r=0.825, p<0.01), and IMP-CVR and ASL-CVR (r=0.736, p<0.01).

CONCLUSIONS

ASL-MRI is equivalent to SPECT and that it might serve as a noninvasive method for mapping CVR in MMD.

A technical perspective for understanding quantitative arterial spin-labeling MR imaging using Q2TIPS

We illustrate the fundamental theoretical principles of arterial spin-labeling (ASL) magnetic resonance imaging (MRI) and show a system that employs the second version of quantitative imaging of perfusion using a single subtraction (Q2TIPS) to quantify cerebral blood flow (CBF). We also discuss the effects of the parameters used in Q2TIPS on CBF values as measured with ASL-MRI.

Topography and associations of perivascular spaces in healthy adults: the Kashima scan study

OBJECTIVE

We investigated whether the topography of MRI-visible perivascular spaces (PVS) is associated with markers of specific underlying small vessel disease, including cerebral microbleed (CMB) distribution, in neurologically healthy adults.

METHODS

We analyzed baseline data of an ongoing Japanese population-based cohort study. PVS were rated in the basal ganglia (BG-PVS) and centrum semiovale (CSO-PVS) on axial T2-weighted MRI using a validated rating scale (score 0-4). BG-PVS degree was classified as low (score <2) or high (score ≥2). CSO-PVS degree was classified as low (score <3) or high (score ≥3). Independent demographic, clinical, and imaging factors for high degree of BG-PVS and CSO-PVS were investigated.

RESULTS

A total of 1,575 neurologically healthy adults were included (mean age 57.1 years, SD 9.7; 47% male). In multivariable analyses, high degree of BG-PVS (n = 212, 14%) was associated with deep or infratentorial CMBs (odds ratio [OR] 2.77, 95% confidence interval [CI] 1.62-4.74), a marker of hypertensive arteriopathy; by contrast, high degree of CSO-PVS (n = 357, 23%) was associated with strictly lobar CMBs (OR 2.49, 95% CI 1.35-4.61), which share risk factors with cerebral amyloid angiopathy. Both high degree of BG-PVS and CSO-PVS were associated with hypertension (OR 2.03, 95% CI 1.46-2.82 and OR 1.39, 95% CI 1.07-1.81, respectively), lacunes (OR 3.35, 95% CI 1.92-5.86; OR 1.83 95% CI 1.08-3.08), and severe white matter hyperintensities (OR 2.17, 95% CI 1.42-3.31; OR 1.35, 95% CI 0.93-1.96), but these associations were stronger for high degree of BG-PVS.

CONCLUSIONS

In a neurologically healthy cohort, the associations of PVS differ according to their topography. PVS distribution may be useful for the early detection and classification of small vessel disease.

Norms of the Mini-Mental state Examination for Japanese subjects that underwent comprehensive brain examinations: the Kashima Scan Study

OBJECTIVE

The distribution of the Mini-Mental State Examination (MMSE) scores by age and educational level was investigated in subjects that underwent comprehensive brain examinations.

METHODS

This cross-sectional study included 1,414 adults without neurological disorders who underwent health-screening tests of the brain, referred to as the "Brain Dock," in our center. The MMSE scores were compared between age groups (40-44, 45-49, 50-54, 55-59, 60-64, 65-69, or ≥70 years) and educational levels [the low education level group (6-12 years) and the high education level group (≥13 years)].

RESULTS

The median age was 59 years, and 763 (54%) were women. There was no significant difference in the MMSE total score between women and men. The stepwise method of the multiple linear regression analysis confirmed that a higher age [β value, -0.129; standard error (S.E.), 0.020; p<0.001], low education level (6-12 years) (β value, -0.226; S.E., 0.075; p=0.003), and women (β values, 0.148; S.E., 0.066; p=0.024) was significantly associated with decreased MMSE score. In general, both the percentile scores and mean scores decreased with aging and were lower in the low education level group than in the high education level group. The degree of decrement in scores with age was stronger in the low education level group than in the high education level group.

CONCLUSION

The provided data for age- and education-specific reference norms will be useful for both clinicians and investigators who perform comprehensive brain examinations to assess the cognitive function of subjects.

Main metabolic pathways of TAK-802, a novel drug candidate for voiding dysfunction, in humans: the involvement of carbonyl reduction by 11β-hydroxysteroid dehydrogenase 1

To investigate species differences in the metabolism of TAK-802, in vitro and in vivo metabolic profiles were compared between humans and animals. TAK-802 was mainly metabolized to M-I, M-II, M-III and M-IV in human and animal liver microsomes. Especially the M-IV formation in humans was greater than that in animals. Likewise, M-IV was detected to a lower extent in the plasma and excreta of animals administered with TAK-802, whereas the AUC0-48 h of M-IV was approximately five-fold higher than that of TAK-802 in human plasma. These results indicate that the in vitro metabolic profile reflects the in vivo condition. Thus, to identify the metabolic pathway of TAK-802 in humans, the responsible enzyme to form M-IV was elucidated in vitro. Since M-IV is a reductive metabolite formed in microsomes, the possibility of involvement of 11β-hydroxysteroid dehydrogenase (11β-HSD), a carbonyl reductase located in microsomes, was first investigated. Consequently, M-IV formation was confirmed by incubation with human 11β-HSD1-expressing microsomes and was concentration-dependently inhibited by glycyrrhetinic acid, an inhibitor for 11β-HSD enzymes, indicating the involvement of 11β-HSD1 in the M-IV formation. In contrast, little M-IV formation was observed using rat 11β-HSD1, suggesting species differences between humans and rats. In addition, M-II was formed via M-IV, not via M-I and the CYP identification studies revealed that both M-I formation from TAK-802 and M-II formation from M-IV were mainly catalyzed by CYP3A4. In conclusion, 11β-HSD1 and CYP3A4 are principally responsible for the metabolism of TAK-802 in humans and 11β-HSD1 may be responsible for the observed species difference.