Cortical superficial siderosis and bleeding risk in cerebral amyloid angiopathy: A meta-analysis

Incidence of Amyloid-Related Imaging Abnormalities in Phase III Clinical Trials of Anti-Amyloid-β Immunotherapy: An Updated Meta-Analysis

BACKGROUND AND OBJECTIVES

Amyloid-related imaging abnormalities (ARIA) are key safety considerations in anti-amyloid-β (Aβ) immunotherapy. ARIA can be categorized into 2 types: ARIA characterized by edema and effusion (ARIA-E) or microhemorrhages and superficial siderosis (ARIA-H). In this study, we assessed the incidence of ARIA in phase 3 randomized controlled trials (RCTs) of anti-Aβ immunotherapy and compared the incidence among different agents and APOE ε4 carrier status.

METHODS

PubMed and Embase databases were searched for phase 3 RCTs of anti-Aβ immunotherapy published on or before May 23, 2024. The inclusion criteria were phase 3 trials of anti-Aβ immunotherapy for mild cognitive impairment due to Alzheimer disease (AD) or mild AD dementia, with sufficient data on ARIA-E/H. The pooled incidences of ARIA and subgroup analyses according to various agents and APOE ε4 carrier status were calculated. A sensitivity analysis excluding outliers was performed. The pooled odds ratio (OR) of ARIA-E according to the APOE ε4 carrier status was also calculated.

RESULTS

Nine phase 3 RCT cohorts from 8 eligible studies were identified, analyzing data from 6,315 patients. The pooled incidence of ARIA-E was 9.5% (95% CI 2.8%-27.3%), and the adjusted pooled incidence of ARIA-E was 25.5% (95% CI 20.4%-31.8%) in the sensitivity analysis. The pooled incidence of symptomatic ARIA-E was 6.7% (95% CI 3.5%-12.5%) and that of severe ARIA-E was 3.5% (95% CI 13.8%-8.4%). The pooled incidence of ARIA-H was 17.8% (95% CI 11.0%-27.5%), with the incidence of superficial siderosis was 9.3% (95% CI 6.1%-13.9%). The pooled incidence of isolated ARIA-H was 8.7% (95% CI 7.6%-10.1%). Subgroup analysis showed that homozygous APOE ε4 carriers had significantly higher odds of developing ARIA-E (OR 5.6, 95% CI 3.8-8.2, p < 0.001) than noncarriers. Heterozygous APOE ε4 carriers also had significantly higher odds of developing ARIA-E (OR 1.9, 95% CI 1.5-2.4, p < 0.001) than noncarriers.

DISCUSSION

Although limited by small sample size and cohort-level data, our meta-analysis shows the adjusted pooled incidence of ARIA-E was 25.5% and the pooled incidence of ARIA-H was 17.8% in the recent phase 3 RCTs of anti-Aβ immunotherapy. Homozygous APOE ε4 carriers have a 5.6-fold higher risk of developing ARIA-E than noncarriers.

Cerebrospinal Fluid Beta-Amyloid Concentration and Clinical and Radiographic Manifestations of Cerebral Amyloid Angiopathy

BACKGROUND

Cerebral amyloid angiopathy (CAA) is driven by vascular Aβ (amyloid-beta) deposition, which can be detected as reduced Aβ species in cerebrospinal fluid (CSF). We sought to identify relationships between CSF Aβ and tau concentrations and various manifestations of CAA.

METHODS

This is a retrospective cross-sectional single-center study of patients diagnosed with CAA per Boston Criteria version 2.0, had magnetic resonance imaging brain scans, and underwent CSF testing for Aβ and tau concentrations between 2008 and 2022. Associations between clinical/magnetic resonance imaging features and CSF biomarker concentrations were investigated with univariate and multivariate models.

RESULTS

We identified 31 patients aged 69.6±8.4 years, of whom 20 presented with cognitive complaints, 9 with CAA-related macrohemorrhage (lobar intraparenchymal or convexity subarachnoid hemorrhage), and 2 with transient focal neurological episodes. Presence of macrohemorrhage (301.8±112 pg/mL versus 400.9±123 pg/mL, P=0.029), cortical superficial siderosis (309.6±131 mg/dL versus 412.3±100 pg/mL, P=0.021), and severe enlarged perivascular spaces in centrum semiovale (285.8±91 pg/mL versus 428.3±117 pg/mL, P<0.001) were associated with lower Aβ42 concentrations. Aβ42 concentrations inversely correlated with the number of these manifestations, being lowest in patients having all three. Patients with cognitive complaints had higher t-tau (total tau; 551±320 pg/mL versus 317.2±141 pg/mL, P=0.03) and trended toward having higher p-tau (phosphorylated tau at threonine 181) concentrations (75.69±39 pg/mL versus 49.24±22 pg/mL, P=0.05).

CONCLUSIONS

Lower CSF Aβ42, suggesting higher amyloid burden, is associated with CAA-related macrohemorrhages and severe enlarged perivascular spaces in centrum semiovale, suggesting potential mechanistic links and CSF Aβ42 as a potential biomarker for progression of CAA. CSF tau concentrations are linked to cognitive complaints, likely representing comorbid Alzheimer disease pathology.

Increased Plasma β-Secretase 1 Activity Correlates With Neurodegeneration in Cerebral Small Vessel Disease

BACKGROUND

β-secretase 1 (BACE1) plays a key role in amyloidogenic pathway and is considered a new mechanism for cerebral small vessel disease (CSVD). We explore the potential role of plasma BACE1 in CSVD and the pathological process it may be involved in.

METHODS AND RESULTS

We enrolled 163 participants with CSVD (114 cerebral amyloid angiopathy and 49 hypertensive hemorrhage), and 96 cognitively unimpaired elders and 40 participants with Alzheimer's disease as controls. We measured BACE1 activity using a synthetic fluorescence substrate enzyme-linked immunosorbent assay. We used regression models to investigate associations between BACE1 and imaging and blood markers as well as clinical outcomes in CSVD. Plasma BACE1 activity was significantly higher in CSVD (median 862.0 relative fluorescence units [RFU], interquartile range 700.6-1032.9) compared with elder controls (522.5 RFU, 438.3-662.1, P<0.001) but lower than Alzheimer's disease (964.0 RFU, 838.4-1225.0, P=0.032). For CSVD, there was an association between plasma and cerebrospinal fluid BACE1 activity (β=0.50, P=0.030). Plasma BACE1 activity was negatively associated with hippocampal volume (coefficient -2.40, P<0.001), and positively associated with blood neurofilament light chain (coefficient 0.08, P<0.001) and total tau (coefficient 0.15, P=0.006) but not with specific cerebrovascular imaging markers. During 2-year follow-up, BACE1 activity was independently related to dementia conversion (odds ratio, 17.72; P=0.001) but not stroke in CSVD.

CONCLUSIONS

Plasma BACE1 activity is moderately increased and associated with neurodegeneration and cognitive impairment risk in CSVD. It indicates that BACE1 is a promising biomarker especially for CSVD-related neurodegeneration.

A bibliometric analysis of cerebral small vessel disease

Background

Cerebral small vessel disease (CSVD) is a significant contributor to both stroke and dementia. While numerous studies on CSVD have been published, herein, we have conducted a bibliometric examination of the literature on CSVD, revealing its hot spots and emerging patterns.

Methods

We used the Web of Science Core Collection as our primary database and conducted a literature search from January 2008 to January 2023. CiteSpace, VOSviewer, online bibliometric platform, and R-bibliometrix were employed to conduct bibliometric analysis and network visualization, including the number of publications, countries, institutions, journals, citations, authors, references, and keywords.

Results

A total of 4891 publications on CSVD were published in 790 journals by 19,066 authors at 3,862 institutions from 84 countries. The United States produced the most written works and had a significant impact in this field of study. The University of Edinburgh had the highest publication count overall. The journal with the most publications and co-citations was Stroke. Wardlaw, Joanna was the most prolific author and commonly cited in the field. The current areas of research interest revolved around "MRI segmentation" and "Enlarged perivascular spaces in the basal ganglia."

Conclusion

We conducted a bibliometric analysis to examine the advancements, focal points, and cutting-edge areas in the field of CSVD to reveal potential future research opportunities. Research on CSVD is currently rapidly advancing, with a consistent rise in publications on the topic since 2008. At the same time, we identified leading countries, institutions, and leading scholars in the field and analyzed journals and representative literature. Keyword co-occurrence analysis and burst graph emergence detection identified MRI segmentation and Basal ganglia enlarged perivascular spaces as the most recent areas of research interest.

Clinical characteristics of cerebral amyloid angiopathy and risk factors of cerebral amyloid angiopathy related intracerebral hemorrhage

OBJECTIVES

There is limited understanding of the differences between cerebral amyloid angiopathy (CAA) with and without intracerebral hemorrhage (ICH). This article aimed to describe the characteristics of CAA and identify the risk factors of CAA-ICH in a multicenter cohort.

METHODS

Patients consecutively enrolled in the national multicenter prospective Cerebral Small Vessel Disease Cohort Study who met the Boston diagnostic criteria for CAA or CAA-related inflammation were included in this study. The demographic characteristics and clinical data were collected. The clinical and radiographic differences between CAA with and without ICH were compared to identify the risk factors for CAA-ICH.

RESULTS

A total of 219 CAA patients were included, with an average age of 67.12 ± 9.93. Of all patients, 26.0% were CAA with ICH. Univariate analysis showed that CAA-ICH is associated with carrying more APOE ε2 allele, less lobar cerebral microbleeds (CMBs), cortical superficial siderosis (cSS), lower Fazekas scale, a tendency of gait disorder, and acute onset (P < 0.05). The generalized linear mixed model yielded statistically significant associations between CAA with ICH and carrying the APOE ε2 allele, cSS, the lower number of lobar CMBs, and the lower Fazekas scale (P < 0.05).

CONCLUSION

It is meaningful to classify CAA with and without ICH, as there may be different mechanisms between the two. CAA with ICH has a susceptibility to carrying APOE ε2, cSS, and a relatively small number of CMBs. Fewer CMBs do not mean lower susceptibility to ICH in CAA. Larger prospective cohort studies are necessary to further clarify these conclusions.

The Spectrum of Cerebral Small Vessel Disease: Emerging Pathophysiologic Constructs and Management Strategies

Cerebral small vessel disease (CSVD) is a spectrum of disorders that affect small arterioles, venules, cortical and leptomeningeal vessels, perivascular spaces, and the integrity of neurovascular unit, blood brain barrier, and surrounding glia and neurons. CSVD is an important cause of lacunar ischemic stroke and sporadic hemorrhagic stroke, as well as dementia-which will constitute some of the most substantive population and public health challenges over the next century. This article provides an overview of updated pathophysiologic frameworks of CSVD; discusses common and underappreciated clinical and neuroimaging manifestations of CSVD; and reviews emerging genetic risk factors linked to sporadic CSVD.

SWI versus GRE-T2*: Assessing cortical superficial siderosis in advanced cerebral amyloid angiopathy

BACKGROUND AND PURPOSE

Cortical superficial siderosis (cSS) is a key neuroimaging marker of cerebral amyloid angiopathy (CAA) detected on blood-sensitive magnetic resonance imaging (MRI). We aimed to assess cSS in advanced CAA patients and explore differences in its evaluation between susceptibility weighted imaging (SWI) and gradient recalled echo-T2* (GRE-T2*).

MATERIALS AND METHODS

Neuroimaging data gathered from a prospective cohort of CAA patients with probable or definite CAA were retrospectively analyzed by two independent raters. SWI and GRE-T2* were used to assess presence and severity (absent, focal [≤3 sulci] or disseminated [>3 sulci]) of cSS and number of foci. Ratings were compared between sequences and inter-rater agreement was determined. Post hoc analysis explored differences in cSS multifocality scores.

RESULTS

We detected cSS in 38 patients with SWI and in 36 with GRE-T2* (70.4% versus 66.7%; P=0.5). The two raters agreed in detecting more disseminated cSS when using SWI: 16 focal (29.63%) and 20 disseminated (37.04%) cases of cSS seen on GRE-T2* and 11 (20.37%) focal and 27 (50%) disseminated cSS cases seen using SWI (P=0.008). Inter-rater agreement was equivalent for the two sequences (κpresence 0.7 versus 0.69; κseverity 0.74 versus 0.66) for assessing both presence and severity of cSS. Post hoc analysis showed higher multifocality scores from both raters' SWI evaluations, with agreement equivalent to that for T2* evaluations.

CONCLUSIONS

Our findings suggest that SWI ratings could show more disseminated cSS and higher multifocality scores in advanced CAA patients with inter-rater reliability equivalent to that obtained using GRE-T2*, regardless of level of experience.

Management of cerebral amyloid angiopathy and atrial fibrillation: We are still far from precision medicine

The use of anticoagulation therapy could prove to be controversial when trying to balance ischemic stroke and intracranial bleeding risks in patients with concurrent cerebral amyloid angiopathy (CAA) and atrial fibrillation (AF). In fact, CAA is an age-related cerebral vasculopathy that predisposes patients to intracerebral hemorrhage. Nevertheless, many AF patients require oral systemic dose-adjusted warfarin, direct oral anticoagulants (such as factor Xa inhibitors) or direct thrombin inhibitors to control often associated with cardioembolic stroke risk. The prevalence of both CAA and AF is expected to rise, due to the aging of the population. This clinical dilemma is becoming increasingly common. In patients with coexisting AF and CAA, the risks/benefits profile of anticoagulant therapy must be assessed for each patient individually due to the lack of a clear-cut consensus with regard to its risks in scientific literature. This review aims to provide an overview of the management of patients with concomitant AF and CAA and proposes the implementation of a risk-based decision-making algorithm.

Infratentorial superficial siderosis: report of six cases and review of the literature

Objectives

To investigate the etiology, clinical manifestations, imaging features, and treatment of patients with infratentorial superficial siderosis (iSS), enhance clinicians' comprehension of this rare disease, and conduct oral deferiprone intervention and subsequent monitoring.

Methods

Six patients diagnosed with iSS based on magnetic resonance imaging (MRI) and susceptibility weighted imaging (SWI) were enrolled from 2021 to 2023 at the First Affiliated Hospital of Fujian Medical University. Their clinical datas were summarized, and the etiology and imaging characteristics were analyzed. Follow-up was conducted through telephone or outpatient visits.

Results

Among the 6 patients, there were 3 males and 3 females. The onset age ranged from 35 to 71 years, with an average onset age of 53 years. The clinical symptoms mainly included acoustic disturbances (6/6), gait imbalance (6/6), dysolfactory (6/6), cognitive impairment (2/6), epilepsy (2/6), and pyramidal tract sign (2/6). Evidence of superficial siderosis was observed on MRI across the cortex, brainstem, cerebellum, and spinal cord in all patients. T2-space sequence MRI revealed two instances of dural tear. During the follow-up period ranging from 1 month to 3 years, three patients who received oral deferiprone treatment showed improvement, whereas the remaining three patients who declined deferiprone treatment demonstrated progression.

Conclusion

The primary clinical manifestations of iSS include bilateral sensorineural hearing disturbances, progressive cerebellar ataxia, and spinal cord lesions. The key diagnostic criteria involve the presence of linear hypointensity on T2-WI in the surface region of the nervous system. Dural tear caused by various factors is considered to be the most common cause of iSS, and its treatment mainly involves surgical intervention for hemorrhagic primary diseases as well as pharmacotherapy with deferiprone.

[Cerebral Small Vessel Disease: Advances in Understanding its Pathophysiology]

Sporadic cerebral small vessel disease determines age- and vascular-risk-factor-related processes of the small brain vasculature. The underlying pathology develops in a stage-dependent manner - probably over decades - often already starting in midlife. Endothelial and pericyte activation precedes blood-brain barrier leaks, extracellular matrix remodeling and neuroinflammation, which ultimately result in bleeds, synaptic and neural dysfunction. Hemodynamic compromise of the small vessel walls promotes perivascular drainage failure and accumulation of neurotoxic waste products in the brain. Clinical diagnosis is mainly based on magnetic resonance imaging according to the Standards for Reporting Vascular Changes on Neuroimaging 2. Cerebral amyloid angiopathy is particularly stratified according to the Boston v2.0 criteria. Small vessel disease of the brain could be clinically silent, or manifested through a heterogeneous spectrum of diseases, where cognitive decline and stroke-related symptoms are the most common ones. Prevention and therapy are centered around vascular risk factor control, physically and cognitively enriched life style and, presumably, maintenance of a good sleep quality, which promotes sufficient perivascular drainage. Prevention of ischemic stroke through anticoagulation that carries at the same time an increased risk for large brain hemorrhages - particularly in the presence of disseminated cortical superficial siderosis - remains one of the main challenges. The cerebral small vessel disease field is rapidly evolving, focusing on the establishment of early disease stage imaging and biofluid biomarkers of neurovascular unit remodeling and the compromise of perivascular drainage. New prevention and therapy strategies will correspondingly center around the dedicated targeting of, e. g., cellular small vessel wall and perivascular tissue structures. Growing knowledge about brain microvasculature bridging neuroimmunological, neurovascular and neurodegenerative fields might lead to a rethink about apparently separate disease entities and the development of overarching concepts for a common line of prevention and treatment for several diseases.

Impact of previous statin use on first intracerebral hemorrhage in cerebral amyloid angiopathy

OBJECTIVES

Statins have been associated with an increased risk of spontaneous intracerebral hemorrhage (ICH), but without dedicated study in cerebral amyloid angiopathy (CAA). We aimed to evaluate the association between previous statin treatment and radiological hemorrhagic lesions in a CAA population during a first lobar ICH event.

MATERIALS AND METHODS

We retrospectively included all patients meeting the modified Boston criteria for probable CAA and admitted for a first lobar ICH between 2010 and 2021 at Rouen University Hospital. Patients were classified as having previous statin treatment or not. We compared the ICH volume, the number of associated cerebral microbleeds (CMBs), and cortical superficial siderosis (CSS) according to previous statin treatment or not. We also compared functional outcomes and ICH recurrence during the follow-up period between the two groups.

RESULTS

We included 99 patients, 27 of whom had statin treatment prior to their ICH. The ICH volume and the number of CMBs did not differ between groups. Disseminated CSS was initially more frequent in the statin group (88% versus 57%; P=0.019), but this was no longer significant after adjustment for antiplatelet treatment (P=0.13). The long-term outcome was similar between the two groups with no increased risk of ICH recurrence in the statin-treated group (29.63% versus 23.61%, P=0.54).

CONCLUSIONS

Previous statin treatment was not associated with more severe hemorrhagic lesions in CAA in terms of ICH volume or number of microbleeds, but a trend for increased disseminated CSS was highlighted, which will require further larger studies.

Risk factors for recurrent cerebral amyloid angiopathy-related intracerebral hemorrhage

Background

Cerebral amyloid angiopathy (CAA) is the most common cause of lobar intracerebral hemorrhage (ICH) in the elderly, and its multifocal and recurrent nature leads to high rates of disability and mortality. Therefore, this study aimed to summarize the evidence regarding the recurrence rate and risk factors for CAA-related ICH (CAA-ICH).

Methods

We performed a systematic literature search of all English studies published in PubMed, Embase, Web of Science, Cochrane Library, Scopus, and CINAHL from inception to June 10, 2023. Studies reporting CAA-ICH recurrence rates and risk factors for CAA-ICH recurrence were included. We calculated pooled odds ratios (ORs) with their corresponding 95% confidence intervals (CIs) using a random/fixed-effects model based on the I2 assessment of heterogeneity between studies. Publication bias was assessed using Egger's test.

Results

Thirty studies were included in the final analysis. Meta-analysis showed that the recurrence rate of CAA-ICH was 23% (95% CI: 18-28%, I2 = 96.7%). The risk factors significantly associated with CAA-ICH recurrence were: previous ICH (OR = 2.03; 95% CI: 1.50-2.75; I2 = 36.8%; N = 8), baseline ICH volume (OR = 1.01; 95% CI: 1-1.02; I2 = 0%; N = 4), subarachnoid hemorrhage (cSAH) (OR = 3.05; 95% CI: 1.86-4.99; I2 = 0%; N = 3), the presence of cortical superficial siderosis (cSS) (OR = 2.04; 95% CI: 1.46-2.83; I2 = 0%; N = 5), disseminated cSS (OR = 3.21; 95% CI: 2.25-4.58; I2 = 16.0%; N = 6), and centrum semiovale-perivascular spaces (CSO-PVS) severity (OR = 1.67; 95% CI: 1.14-2.45; I2 = 0%; N = 4).

Conclusion

CAA-ICH has a high recurrence rate. cSAH, cSS (especially if disseminated), and CSO-PVS were significant markers for recurrent CAA-ICH. The onset of ICH in patients with CAA is usually repeated several times, and recurrence is partly related to the index ICH volume. Identifying clinical and neuroimaging predictors of CAA-ICH recurrence is of great significance for evaluating outcomes and improving the prognosis of patients with CAA-ICH.

Systematic review registration

https://www.crd.york.ac.uk/PROSPERO/display_record.php?RecordID=400240, identifier [CRD42023400240].

Clinical Characteristics, Neuroimaging Markers, and Outcomes in Patients with Cerebral Amyloid Angiopathy: A Prospective Cohort Study

Background and purpose: Sporadic cerebral amyloid angiopathy (CAA) is a small vessel disease, resulting from progressive amyloid-β deposition in the media/adventitia of cortical and leptomeningeal arterioles. We sought to assess the prevalence of baseline characteristics, clinical and radiological findings, as well as outcomes among patients with CAA, in the largest study to date conducted in Greece. Methods: Sixty-eight patients fulfilling the Boston Criteria v1.5 for probable/possible CAA were enrolled and followed for at least twelve months. Magnetic Resonance Imaging was used to assess specific neuroimaging markers. Data regarding cerebrospinal fluid biomarker profile and Apolipoprotein-E genotype were collected. Multiple logistic regression analyses were performed to identify predictors of clinical phenotypes. Cox-proportional hazard regression models were used to calculate associations with the risk of recurrent intracerebral hemorrhage (ICH). Results: Focal neurological deficits (75%), cognitive decline (57%), and transient focal neurological episodes (TFNEs; 21%) were the most common clinical manifestations. Hemorrhagic lesions, including lobar cerebral microbleeds (CMBs; 93%), cortical superficial siderosis (cSS; 48%), and lobar ICH (43%) were the most prevalent neuroimaging findings. cSS was independently associated with the likelihood of TFNEs at presentation (OR: 4.504, 95%CI:1.258-19.088), while multiple (>10) lobar CMBs were independently associated with cognitive decline at presentation (OR:5.418, 95%CI:1.316-28.497). cSS emerged as the only risk factor of recurrent ICH (HR:4.238, 95%CI:1.509-11.900) during a median follow-up of 20 months. Conclusions: cSS was independently associated with TFNEs at presentation and ICH recurrence at follow-up, while a higher burden of lobar CMBs with cognitive decline at baseline. These findings highlight the prognostic value of neuroimaging markers, which may influence clinical decision-making.

Cortical superficial siderosis is associated with reactive astrogliosis in cerebral amyloid angiopathy

BACKGROUND

Cortical superficial siderosis (cSS) has recently emerged as one of the most important predictors of symptomatic intracerebral hemorrhage and is a risk factor for post-stroke dementia in cerebral amyloid angiopathy (CAA). However, it remains unknown whether cSS is just a marker of severe CAA pathology or may itself contribute to intracerebral hemorrhage risk and cognitive decline. cSS is a chronic manifestation of convexal subarachnoid hemorrhage and is neuropathologically characterized by iron deposits in the superficial cortical layers. We hypothesized that these iron deposits lead to local neuroinflammation, a potentially contributory pathway towards secondary tissue injury.

METHODS

Accordingly, we assessed the distribution of inflammatory markers in relation to cortical iron deposits in post-mortem tissue from CAA cases. Serial sections from the frontal, parietal, temporal, and occipital lobes of nineteen autopsy cases with CAA were stained with Perls' Prussian blue (iron) and underwent immunohistochemistry against glial fibrillary acidic protein (GFAP, reactive astrocytes) and cluster of differentiation 68 (CD68, activated microglia/macrophages). Digitized sections were uploaded to the cloud-based Aiforia® platform, where deep-learning algorithms were utilized to detect tissue, iron deposits, and GFAP-positive and CD68-positive cells.

RESULTS

We observed a strong local relationship between cortical iron deposits and reactive astrocytes. Like cSS-related iron, reactive astrocytes were mainly found in the most superficial layers of the cortex. Although we observed iron within both astrocytes and activated microglia/macrophages on co-stains, there was no clear local relationship between the density of microglia/macrophages and the density of iron deposits.

CONCLUSION

Iron deposition resulting from cSS is associated with local reactive astrogliosis.

Neuroimaging standards for research into small vessel disease-advances since 2013

Cerebral small vessel disease (SVD) is common during ageing and can present as stroke, cognitive decline, neurobehavioural symptoms, or functional impairment. SVD frequently coexists with neurodegenerative disease, and can exacerbate cognitive and other symptoms and affect activities of daily living. Standards for Reporting Vascular Changes on Neuroimaging 1 (STRIVE-1) categorised and standardised the diverse features of SVD that are visible on structural MRI. Since then, new information on these established SVD markers and novel MRI sequences and imaging features have emerged. As the effect of combined SVD imaging features becomes clearer, a key role for quantitative imaging biomarkers to determine sub-visible tissue damage, subtle abnormalities visible at high-field strength MRI, and lesion-symptom patterns, is also apparent. Together with rapidly emerging machine learning methods, these metrics can more comprehensively capture the effect of SVD on the brain than the structural MRI features alone and serve as intermediary outcomes in clinical trials and future routine practice. Using a similar approach to that adopted in STRIVE-1, we updated the guidance on neuroimaging of vascular changes in studies of ageing and neurodegeneration to create STRIVE-2.

Subarachnoid CSF hyperintensities at 7 tesla FLAIR MRI: A novel marker in cerebral amyloid angiopathy

BACKGROUND

We observed subarachnoid cerebrospinal fluid (CSF) hyperintensities at non-contrast 7-tesla (T) fluid-attenuated inversion recovery (FLAIR) MRI, frequently topographically associated with cortical superficial siderosis (cSS), in participants with cerebral amyloid angiopathy (CAA). To systemically evaluate these CSF hyperintensities we investigated their frequency and anatomical and temporal relationship with cSS on 7T and 3T MRI in hereditary Dutch-type CAA (D-CAA), sporadic CAA (sCAA), and non-CAA controls.

METHODS

CAA participants were included from two prospective natural history studies and non-CAA controls from a 7T study in healthy females and females with ischemic stroke. CSF hyperintensities were scored by two independent observers.

RESULTS

We included 38 sCAA participants (mean age 72y), 50 D-CAA participants (mean age 50y) and 44 non-CAA controls (mean age 53y, 15 with stroke). In total 27/38 (71 %, 95 %CI 56-84) sCAA and 23/50 (46 %, 95 %CI 33-60) D-CAA participants had subarachnoid CSF hyperintensities at baseline 7T. Most (96 %) of those had cSS, in 54 % there was complete topographical overlap with cSS. The remaining 46 % had ≥1 sulcus with CSF hyperintensities without co-localizing cSS. None of the healthy controls and 2/15 (13 %, 95 %CI 2-41, 100 % cSS overlap) of the stroke controls had CSF hyperintensities. In 85 % of the CAA participants CSF hyperintensities could retrospectively be identified at 3T. Of the 35 CAA participants with follow-up 7T after two years, 17/35 (49 %) showed increase and 6/35 (17 %) decrease of regional CSF hyperintensities. In 2/11 (18 %) of participants with follow-up who had baseline CSF hyperintensities without overlapping cSS, new cSS developed at those locations.

CONCLUSIONS

Subarachnoid CSF hyperintensities at 7T FLAIR MRI occur frequently in CAA and are associated with cSS, although without complete overlap. We hypothesize that the phenomenon could be a sign of subtle plasma protein or blood product leakage into the CSF, resulting in CSF T1-shortening.

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.

Epilepsy in cerebral amyloid angiopathy: an observational retrospective study of a large population

OBJECTIVE

Cerebral amyloid angiopathy (CAA) is a major cause of spontaneous intracranial hemorrhage in older adults. Epilepsy represents a possible sequela of the disease. To date, studies on epilepsy in CAA are lacking, and the few data available mainly focus on CAA-related inflammation (CAA-ri), the inflammatory form of the disease.

METHODS

In this retrospective observational study, we consecutively recruited CAA patients observed over a time span of 10 years, collecting demographic, clinical, and instrumental data. Significant baseline characteristics were evaluated as potential risk factors for the development of epilepsy in the CAA population, and in the subgroups of CAA-ri and CAA without inflammatory reaction (CAA-nri). The effect of potential risk factors for epilepsy was measured as odds ratio with 95% confidence interval.

RESULTS

Within 96 recruited CAA cases, 33 (34.4%) developed epilepsy during follow-up (median = 13.5 months). The prevalent type of seizure was focal (81.3%); 12.1% of the epileptic patients presented status epilepticus, and 6.1% developed drug-resistant epilepsy. Electroencephalographic traces revealed slow and epileptic discharge activity in the majority of epileptic patients, but also in those without epilepsy. The presence of focal or disseminated cortical superficial siderosis (cSS) was associated with an increased risk of epilepsy in the CAA-nri group, and the association with CAA-ri and epilepsy was present in the overall population.

SIGNIFICANCE

Epilepsy is a common manifestation during the course of CAA, where CAA-ri and cSS represent predisposing factors for the development of seizures. These data suggest the importance of a deep characterization of CAA patients, to better select those more prone to develop epilepsy.

Role of Inflammatory Processes in Hemorrhagic Stroke

Hemorrhagic stroke is the deadliest form of stroke and includes the subtypes of intracerebral hemorrhage and subarachnoid hemorrhage. A common cause of hemorrhagic stroke in older individuals is cerebral amyloid angiopathy. Intracerebral hemorrhage and subarachnoid hemorrhage both lead to the rapid collection of blood in the central nervous system and generate inflammatory immune responses that involve both brain resident and infiltrating immune cells. These responses are complex and can contribute to both tissue recovery and tissue injury. Despite the interconnectedness of these major subtypes of hemorrhagic stroke, few reviews have discussed them collectively. The present review provides an update on inflammatory processes that occur in response to intracerebral hemorrhage and subarachnoid hemorrhage, and the role of inflammation in the pathophysiology of cerebral amyloid angiopathy-related hemorrhage. The goal is to highlight inflammatory processes that underlie disease pathology and recovery. We aim to discuss recent advances in our understanding of these conditions and identify gaps in knowledge with the potential to develop effective therapeutic strategies.

The effects of imaging markers on clinical trajectory in cerebral amyloid angiopathy: a longitudinal study in a memory clinic

BACKGROUND

We investigated the relevance of various imaging markers for the clinical trajectory of cerebral amyloid angiopathy (CAA) patients in a memory clinic.

METHODS

A total of 226 patients with probable CAA were included in this study with a mean follow-up period of 3.5 ± 2.7 years. Although all had more than one follow-up visit, 173 underwent follow-up Mini-Mental Status Examination (MMSE) and Clinical Dementia Rating Sum of Boxes (CDR-SB) ranging from 2 to 15 time points. Among 226, 122 patients underwent amyloid-β (Aβ) PET imaging. The prevalence of intracerebral hemorrhage (ICH) and its imaging predictors was investigated. The effects of CAA imaging markers and Aβ PET positivity on longitudinal cognition based on the MMSE and CDR-SB were evaluated using mixed effects models.

RESULTS

During the follow-up, 10 (4.4%) patients developed ICH: cortical superficial siderosis (cSS; hazard ratio [HR], 6.45) and previous lobar ICH (HR, 4.9), but lobar cerebral microbleeds (CMBs) were not predictors of ICH development. The presence of CMIs (p = 0.045) and Aβ positivity (p = 0.002) were associated with worse MMSE trajectory in CAA patients. Regarding CDR-SB trajectory, only Aβ positivity was marginally associated with worse longitudinal change (p = 0.050).

CONCLUSION

The results of the present study indicated that various imaging markers in CAA patients have different clinical relevance and predictive values for further clinical courses.

Cerebral amyloid angiopathy: clinical presentations and management challenges in the Australian context

Cerebral amyloid angiopathy (CAA) is a disease with several clinical manifestations. It is characterised by amyloid-beta deposition in cerebral blood vessels, making them prone to bleeding. The incidence of CAA increases with age and may be associated or co-exist with intraparenchymal neurodegenerative proteinopathies, which makes it an increasingly relevant condition for adult physicians in all areas of medical practice. The vast majority of cases of CAA are sporadic with a small minority of familial cases. CAA is asymptomatic in many older adults but increases the risk of fatal intracerebral or subarachnoid haemorrhage. We review the existing literature on CAA and summarise the key findings. We specifically explore clinical challenges relevant to CAA, particularly in diagnosis, management of intracranial haemorrhage and management of concurrent medical conditions.

Lesson of the month: Cerebral amyloid angiopathy masquerading as recurrent transient ischaemia attacks in an older adult

Cerebral amyloid angiopathy (CAA) is a common cause of lobar cerebral haemorrhage in elderly populations, which can present as transient focal neurological episodes (TFNEs) or sometimes known as 'amyloid spells'. CAA-TFNE poses a common diagnostic challenge to physicians as it can be difficult to distinguish from transient ischaemic attacks or other transient neurologic syndromes. Prompt recognition of CAA is crucial as it heralds a high risk of intracerebral haemorrhage and to avoid unnecessary investigation with inappropriate long-term prevention treatment.

Deep Brain Stimulation in a Patient with Parkinson's Disease and Cortical Superficial Siderosis

Cortical superficial siderosis (cSS) is a rare condition that is regarded as a potential magnetic resonance marker of cerebral amyloid angiopathy (CAA). We describe the case of a 68-year-old man with cSS and Parkinson's disease (PD) who subsequently exhibited incidental microhemorrhages, which were only detected on magnetic resonance imaging (MRI), at one week after deep brain stimulation (DBS) surgery. cSS is now considered to be a significant risk factor for CAA and future bleeding. Therefore, because DBS surgery is invasive and may increase the risk of intracerebral hemorrhage, the procedure should be performed carefully when managing patients with PD and CAA.

Updated Outlook of Cerebral Amyloid Angiopathy and Inflammatory Subtypes: Pathophysiology, Clinical Manifestations, Diagnosis and Management

Cerebral amyloid angiopathy (CAA) is a common untreatable cause of lobar hemorrhages and cognitive decline in the older population. Subset of patients present with its inflammatory subtype with rapid decline in cognitive functions and neurological deficits. Most commonly the underlying pathophysiology of this disease is deposition of insoluble amyloid protein into blood vessel walls which results in vessel fragility leading to local neurotoxicity which may eventually leads to lobar hemorrhages and cognitive decline. The term “Amyloid Spell” encompasses transient focal neurological deficits which is commonly misdiagnosed as seizures or transient ischemic attack in the emergency department. Radiologic findings in these patients may reveal microbleeds, cortical superficial siderosis, white matter hyperintensities, and cerebral edema which support the clinical diagnosis which could be otherwise challenging. CAA diagnostic criteria require CT (Edinburgh Criteria) or MRI imaging, or neuropathology. The diagnosis can be suspected without imaging or neuropathology but cannot be confirmed. This review article provides a critical outlook on different types of presentations, updated diagnostic criteria and management of CAA patients illustrating underlying mechanisms associated with neuronal injury secondary to amyloid deposition.

The Value of Neuroimaging in Dementia Diagnosis

PURPOSE OF REVIEW

This article discusses neuroimaging in dementia diagnosis, with a focus on new applications of MRI and positron emission tomography (PET).

RECENT FINDINGS

Although the historical use of MRI in dementia diagnosis has been supportive to exclude structural etiologies, recent innovations allow for quantification of atrophy patterns that improve sensitivity for supporting the diagnosis of dementia causes. Neuronuclear approaches allow for localization of specific amyloid and tau neuropathology on PET and are available for clinical use, in addition to dopamine transporter scans in dementia with Lewy bodies and metabolic studies with fludeoxyglucose PET (FDG-PET).

SUMMARY

Using computerized software programs for MRI analysis and cross-sectional and longitudinal evaluations of hippocampal, ventricular, and lobar volumes improves sensitivity in support of the diagnosis of Alzheimer disease and frontotemporal dementia. MRI protocol requirements for such quantification are three-dimensional T1-weighted volumetric imaging protocols, which may need to be specifically requested. Fluid-attenuated inversion recovery (FLAIR) and 3.0T susceptibility-weighted imaging (SWI) sequences are useful for the detection of white matter hyperintensities as well as microhemorrhages in vascular dementia and cerebral amyloid angiopathy. PET studies for amyloid and/or tau pathology can add additional specificity to the diagnosis but currently remain largely inaccessible outside of research settings because of prohibitive cost constraints in most of the world. Dopamine transporter PET scans can help identify Lewy body dementia and are thus of potential clinical value.

Higher Cerebral Small Vessel Disease Burden in Patients With Small Intracerebral Hemorrhage

Objective

To investigate the association between cerebral small vessel disease (SVD) and hematoma volume in primary intracerebral hemorrhage (ICH).

Methods

Patients from a prospective ICH cohort were enrolled. Admission and follow-up CT scan within 72 h after onset were reviewed to calculate the final hematoma volume. We evaluated cortical superficial siderosis and the global SVD score, including white matter hyperintensities, lacunes, enlarged perivascular space, and cerebral microbleeds on MRI. We conducted the multivariate logistic regression analyses to explore the association between SVD markers and small ICH, as well as hematoma volume. Hematoma location was stratified into lobar and non-lobar for subgroup analysis.

Results

A total of 187 patients with primary ICH (mean age 62.4 ± 13.4 years, 67.9% male) were enrolled. 94 (50.2%) patients had small ICH. The multivariate logistic regression analysis showed an association between global SVD score and small ICH [adjusted odds ratio (aOR) 1.27, 95% CI 1.03–1.57, p = 0.027] and a trend of higher global SVD score towards non-lobar small ICH (aOR 1.23, 95% CI 0.95–1.58, p = 0.122). In the multivariate linear regression analysis, global SVD score was inversely related to hematoma volume of all ICH (β = −0.084, 95% CI −0.142 to −0.025, p = 0.005) and non-lobar ICH (β = −0.112, 95% CI −0.186 to −0.037, p = 0.004). Lacune (β = −0.245, 95% CI −0.487 to −0.004, p = 0.046) was associated with lower non-lobar ICH volume.

Conclusion

Global SVD score is associated with small ICH and inversely correlated with hematoma volume. This finding predominantly exists in non-lobar ICH.

CT-Visible Convexity Subarachnoid Hemorrhage Predicts Early Recurrence of Lobar Hemorrhage

Background and Purpose

Convexity subarachnoid hemorrhage (cSAH) may predict an increased recurrence risk in cerebral amyloid angiopathy (CAA)-related intracerebral hemorrhage (ICH) survivors. We aimed to investigate whether cSAH detected on CT was related to early recurrence in patients with ICH related to CAA.

Methods

We analyzed data from consecutive lobar ICH patients diagnosed as probable or possible CAA according to the Boston criteria using the method of cohort study. Demographic and clinical data, ICH recurrence at discharge and within 90 days were collected. The association between cSAH detected on CT and early recurrent ICH was analyzed using multivariable logistic regression.

Results

A total of 197 cases (74 [66–80] years) were included. cSAH was observed on the baseline CT of 91 patients (46.2%). A total of 5.1% (10/197) and 9.5% (17/179) of patients experienced ICH recurrence within 2 weeks and 90 days, respectively. The presence of cSAH was related to recurrence within 2 weeks (OR = 5.705, 95%CI 1.070–30.412, P = 0.041) after adjusting for hypertension, previous symptomatic ICH and anticoagulant use. The presence of cSAH was related to recurrence within 90 days (OR 5.473, 95%CI 1.425–21.028, P = 0.013) after adjusting for hypertension, previous symptomatic ICH and intraventricular hemorrhage. The similar results were obtained in other models using different methods to select adjusting variables.

Conclusion

In patients with lobar ICH related to CAA, 5.1% and 9.5% of them experienced ICH recurrence within 2 weeks and 90 days, respectively. CT-visible cSAH was detected in 46.2% of patients and indicates an increased risk for early recurrent ICH.

Repeated recurrent intracerebral hemorrhage may be involved in cerebral amyloid angiopathy-related inflammation: An autopsy case

We report an autopsy case of repeated recurrent intracerebral hemorrhage (ICH) diagnosed as having cerebral amyloid angiopathy-related inflammation (CAA-ri) in a 65-year-old woman. She had no history of hypertension or other risk factors for stroke. She had a history of lobar ICH in the right parietal lobe 30 months prior. Follow-up magnetic resonance imaging (MRI) performed 29 months after the initial ICH revealed superficial siderosis in the left frontal lobe. She initially presented with severe headache and dysarthria. An initial computed tomography (CT) revealed a subarachnoid hemorrhage on the left frontal lobe. One hour later, an epileptic seizure occurred, and another CT performed at the time revealed lobar ICH in the frontal lobe. Emergency surgical hematoma evacuation was performed. The cortical artery was removed from the surgical specimen. Hematoxylin and eosin (HE) staining revealed lymphocytic perivascular cuffs, and immunohistochemical staining revealed abundant amyloid-β (Aβ) deposits. The patient was diagnosed as having CAA-ri. On the next day, and 19, 46, 55, 78, 79, and 85 days after admission, ICH recurred. We did not administer immunosuppressive drugs, such as high-dose corticosteroids or cyclophosphamide, because of the patient's condition. Following the last ICH, the patient died on the 90th day after symptom onset. An autopsy was performed. Histologically, abundant Aβ deposits were observed within the leptomeningeal and cortical arteries. Further dense-cored amyloid plaques were observed in the cortical samples. Our findings that ICH occurred initially three times in the left hemispheres and later five times in the right hemispheres were considered immune-mediated effects on vascular function. Further, superficial hemosiderosis in the left frontal lobe occurred before the first three ICH events, and hyperintensity of the white matter on MRI was identified in the right parietal lobe, a typical finding of CAA-ri. We hypothesize that the inflammatory process in CAA-ri may be related to recurrent ICH.

Histopathological correlates of haemorrhagic lesions on ex vivo magnetic resonance imaging in immunized Alzheimer's disease cases

Haemorrhagic amyloid-related imaging abnormalities on MRI are frequently observed adverse events in the context of amyloid β immunotherapy trials in patients with Alzheimer's disease. The underlying histopathology and pathophysiological mechanisms of haemorrhagic amyloid-related imaging abnormalities remain largely unknown, although coexisting cerebral amyloid angiopathy may play a key role. Here, we used ex vivo MRI in cases that underwent amyloid β immunotherapy during life to screen for haemorrhagic lesions and assess underlying tissue and vascular alterations. We hypothesized that these lesions would be associated with severe cerebral amyloid angiopathy. Ten cases were selected from the long-term follow-up study of patients who enrolled in the first clinical trial of active amyloid β immunization with AN1792 for Alzheimer's disease. Eleven matched non-immunized Alzheimer's disease cases from an independent brain brank were used as 'controls'. Formalin-fixed occipital brain slices were imaged at 7 T MRI to screen for haemorrhagic lesions (i.e. microbleeds and cortical superficial siderosis). Samples with and without haemorrhagic lesions were cut and stained. Artificial intelligence-assisted quantification of amyloid β plaque area, cortical and leptomeningeal cerebral amyloid angiopathy area, the density of iron and calcium positive cells and reactive astrocytes and activated microglia was performed. On ex vivo MRI, cortical superficial siderosis was observed in 5/10 immunized Alzheimer's disease cases compared with 1/11 control Alzheimer's disease cases (κ = 0.5). On histopathology, these areas revealed iron and calcium positive deposits in the cortex. Within the immunized Alzheimer's disease group, areas with siderosis on MRI revealed greater leptomeningeal cerebral amyloid angiopathy and concentric splitting of the vessel walls compared with areas without siderosis. Moreover, greater density of iron-positive cells in the cortex was associated with lower amyloid β plaque area and a trend towards increased post-vaccination antibody titres. This work highlights the use of ex vivo MRI to investigate the neuropathological correlates of haemorrhagic lesions observed in the context of amyloid β immunotherapy. These findings suggest a possible role for cerebral amyloid angiopathy in the formation of haemorrhagic amyloid-related imaging abnormalities, awaiting confirmation in future studies that include brain tissue of patients who received passive immunotherapy against amyloid β with available in vivo MRI during life.

Neuropathology of Vascular Brain Health: Insights From Ex Vivo Magnetic Resonance Imaging-Histopathology Studies in Cerebral Small Vessel Disease

Sporadic cerebral small vessel disease (SVD) is a major contributor to vascular cognitive impairment and dementia in the aging human brain. On neuropathology, sporadic SVD is characterized by abnormalities to the small vessels of the brain predominantly in the form of cerebral amyloid angiopathy and arteriolosclerosis. These pathologies frequently coexist with Alzheimer disease changes, such as plaques and tangles, in a single brain. Conversely, during life, magnetic resonance imaging (MRI) only captures the larger manifestations of SVD in the form of parenchymal brain abnormalities. There appears to be a major knowledge gap regarding the underlying neuropathology of individual MRI-detectable SVD abnormalities. Ex vivo MRI in postmortem human brain tissue is a powerful tool to bridge this gap. This review summarizes current insights into the histopathologic correlations of MRI manifestations of SVD, their underlying cause, presumed pathophysiology, and associated secondary tissue injury. Moreover, we discuss the advantages and limitations of ex vivo MRI-guided histopathologic investigations and make recommendations for future studies.

Recurrent intracerebral hemorrhage in patients with cerebral amyloid angiopathy: a propensity-matched case-control study

OBJECTIVE

Cerebral amyloid angiopathy (CAA) can present with intracerebral hemorrhage (ICH), convexity subarachnoid hemorrhage (SAH), and rarely acute ischemic stroke (AIS). The objective of our study was to compare the readmission rates for recurrent ICH, SAH, and AIS among patients admitted for ICH with and without CAA.

METHODS

Using the National Readmissions Database 2016-2018 we identified patients admitted for ICH with and without a concomitant diagnosis of CAA. Primary outcome of the study was readmission due to ICH. Secondary outcomes included readmissions due to AIS and SAH. Survival analysis was performed, and Kaplan-Meier curves were created to assess for readmissions.

RESULTS

The study consisted of 194,290 patients with ICH, 8247 with CAA and 186,043 without CAA as a concomitant diagnosis. After propensity matching, we identified 7857 hospitalizations with CAA and 7874 without CAA. Patients with CAA had higher risk of readmission due to ICH as compared to those without CAA [hazards ratio (HR) 3.44, 95% confidence interval (CI) 2.55-4.64, P < 0.001] during the mean follow-up period of 181.4 (SD ± 106.4) days. Patients with CAA were also more likely to be readmitted due to SAH (HR 2.52, 95% CI 1.18-5.37, P 0.017) but not due to AIS (HR 0.74, 95% CI 0.54-1.01, P 0.061). Age (HR 0.96 per year increase in age, 95% CI 0.94-0.98, P < 0.001) and Medicare payer (HR 3.31; 95% CI 1.89-5.78, P < 0.001) were independently associated with readmissions due to ICH.

DISCUSSION

Patients admitted for ICH with a concomitant diagnosis of CAA are three times more likely to have readmissions for recurrent ICH compared to patients without CAA.

[Intracerebral hemorrhage under platelet inhibition and oral anticoagulation in patients with cerebral amyloid angiopathy]

Die Durchführung einer oralen Antikoagulation ist bei Patienten mit einer zerebralen Amyloidangiopathie eine therapeutische Herausforderung. Die Assoziation der zerebralen Amyloidangiopathie mit Lobärblutungen, eine hohe Mortalität intrazerebraler Blutungen insbesondere unter oraler Antikoagulation sowie das hohe Rezidivrisiko solcher Blutungen erfordern eine strenge und interdisziplinäre Risiko-Nutzen-Abwägung. Vitamin-K-Antagonisten erhöhen das Risiko für die mit intrazerebralen Blutungen vergesellschaftete Mortalität um 60 % und sollten daher möglichst vermieden bzw. speziellen klinischen Situationen (z. B. mechanischer Aortenklappenersatz) vorbehalten sein. Auch der Einsatz von neuen oralen Antikoagulanzien und Thrombozytenaggregationshemmern bedarf einer strengen Risiko-Nutzen-Abwägung, da auch diese Substanzen das zerebrale Blutungsrisiko erhöhen. Insbesondere bei Patienten mit einer absoluten Arrhyhtmie bei Vorhofflimmern ist der interventionelle Vorhofohrverschluss eine therapeutische Alternative. Darüber hinaus sind weitere klinische Implikationen bei Patienten mit zerebraler Amyloidangiopathie Gegenstand dieser Literaturübersicht, beispielsweise Besonderheiten nach akutem ischämischem Schlaganfall und erforderlicher Sekundärprophylaxe, bei vorherigen intrazerebralen Blutungen und bei Patienten mit kognitiven Defiziten.

Anticoagulation in Acute Neurological Disease

While anticoagulation and its reversal have been of clinical relevance for decades, recent academic and technological advances have expanded the repertoire of its application in neurological disease. The advent of direct oral anticoagulants provides effective, mechanistically elegant, and relatively safer therapeutic options than warfarin for eligible patients at risk for neurological sequelae of prothrombotic states, particularly given the recent availability of corresponding reversal agents. In this review, we examine the provenance, indications, safety, and reversal tools for anticoagulant medications in the context of neurological disease, with specific attention to acute ischemic stroke, cerebral venous sinus thrombosis, and intracerebral hemorrhage. We will use specific clinical scenarios to illustrate the complex factors that must be considered in the use of anticoagulation, including intracranial pathology such as intracerebral hemorrhage, traumatic brain injury, or malignancy; metabolic complications such as chronic kidney disease; pregnancy; and advanced age.

The Use of Serum Matrix Metalloproteinases in Cerebral Amyloid Angiopathy-Related Intracerebral Hemorrhage and Cognitive Impairment

BACKGROUND

Neuroimaging has played a primary role in predicting intracerebral hemorrhage (ICH) recurrence of cerebral amyloid angiopathy (CAA); however, the utilities of biomarkers in CAA-related ICH and cognitive impairment remain unexplored.

OBJECTIVE

To investigate the correlations of serum levels of matrix metalloproteinase-2 (MMP-2), MMP-3, and MMP-9 with CAA-related MRI markers, ICH recurrence, and cognitive status.

METHODS

68 cases with first probable CAA-ICH and 69 controls were recruited. Clinical and imaging data were obtained at baseline and serum MMPs in the acute phase were measured by Luminex multiplex assays. Cognitive status was assessed with the Chinese version of Mini-Mental State Examination within 10-14 days after ICH onset.

RESULTS

Serum MMP-2 level was significantly lower in CAA-ICH patients than controls while MMP-9 was significantly higher. In CAA-ICH patients, MMP-3 level was significantly associated with lobar cerebral microbleeds count after adjusting age, sex, and hypertension (adjusted coefficient 0.368, 95%CI 0.099-0.637, p = 0.008). During a median follow-up of 2.4 years, higher level of MMP-2 predicted lower CAA-ICH recurrence after adjusting age (adjusted HR 0.326, 95%CI 0.122-0.871, p = 0.025), ICH volume (adjusted HR 0.259, 95%CI 0.094-0.715, p = 0.009), total MRI burden of SVD score (adjusted HR 0.350, 95%CI 0.131-0.936, p = 0.037) respectively. Besides, higher level of MMP-2 was significantly associated with decreased risk of cognitive impairment independent of age and ICH volume (adjusted OR 0.054, 95%CI 0.005-0.570, p = 0.015).

CONCLUSION

Serum MMP-2 in acute phase might be a promising biomarker to predict CAA-ICH recurrence and to evaluate the risk of cognitive impairment.

Cerebrovascular disease in patients with cognitive impairment: A white paper from the ESO dementia committee - A practical point of view with suggestions for the management of cerebrovascular diseases in memory clinics

PURPOSE

Practical suggestions on clinical decisions about vascular disease management in patients with cognitive impairment are proposed.

METHODS

The document was produced by the Dementia Committee of the European Stroke Organisation (ESO) based on the evidence from the literature where available and on the clinical experience of the Committee members. This paper was endorsed by the ESO.

FINDINGS

Vascular risk factors and cerebrovascular disease are frequent in patients with cognitive impairment. While acute stroke treatment has evolved substantially in last decades, evidence of management of cerebrovascular pathology beyond stroke in patients with cognitive impairment and dementia is quite limited. Additionally, trials to test some daily-life clinical decisions are likely to be complex, difficult to undertake and take many years to provide sufficient evidence to produce recommendations. This document was conceived to provide some suggestions until data from field trials are available. It was conceived for the use of clinicians from memory clinics or involved specifically in cognitive disorders, addressing practical aspects on diagnostic tools, vascular risk management and suggestions on some therapeutic options.

DISCUSSION AND CONCLUSIONS

The authors did not aim to do an exhaustive or systematic review or to cover all current evidence. The document approach in a very practical way frequent issues concerning cerebrovascular disease in patients with known cognitive impairment.

Cerebral Amyloid Angiopathy-Related Transient Focal Neurologic Episodes

Transient focal neurologic episodes (TFNEs) are brief disturbances in motor, somatosensory, visual, or language functions that can occur in patients with cerebral amyloid angiopathy (CAA) and may be difficult to distinguish from TIAs or other transient neurologic syndromes. They herald a high rate of future lobar intracerebral hemorrhage, making it imperative to differentiate them from TIAs to avoid potentially dangerous use of antithrombotic drugs. Cortical spreading depression or depolarization triggered by acute or chronic superficial brain bleeding, a contributor to brain injury in other neurologic diseases, may be the underlying mechanism. This review discusses diagnosis, pathophysiology, and management of CAA-related TFNEs.

Superficial Siderosis: A Clinical Review

Superficial siderosis of the central nervous system results from subpial hemosiderin deposition due to chronic low-grade bleeding into the subarachnoid space. The confluent and marginal subpial hemosiderin is best appreciated on iron-sensitive magnetic resonance imaging sequences. With widespread use of magnetic resonance imaging, the disorder is increasingly being recognized, including in asymptomatic individuals. Gait ataxia, often with hearing impairment is a common clinical presentation. A clinical history of subarachnoid hemorrhage is generally not present. A macrovascular pathology is generally not causative. The most common etiology is dural disease, often dural tears. Prior or less commonly ongoing symptoms of craniospinal hypovolemia may be present. Common etiologies for dural tears include disc disease and trauma, including surgical trauma. Patients with dural tears due to herniated and calcified discs often have a ventral intraspinal fluid collection due to cerebrospinal fluid leak. A precise identification of the dural tear relies on multimodality imaging. It has been speculated that chronic bleeding from fragile blood vessels around the dural tear may be the likely underlying mechanism. Surgical correction of the bleeding source is a logical therapeutic strategy. Clinical outcomes are variable, although neuroimaging evidence of successful dural tear repair is noted. The currently available data regarding use of deferiprone in patients with superficial siderosis is insufficient to recommend its routine use in patients. ANN NEUROL 2021;89:1068-1079.

Current Management and Therapeutic Strategies for Cerebral Amyloid Angiopathy

Cerebral amyloid angiopathy (CAA) is characterized by accumulation of amyloid β (Aβ) in walls of leptomeningeal vessels and cortical capillaries in the brain. The loss of integrity of these vessels caused by cerebrovascular Aβ deposits results in fragile vessels and lobar intracerebral hemorrhages. CAA also manifests with progressive cognitive impairment or transient focal neurological symptoms. Although development of therapeutics for CAA is urgently needed, the pathogenesis of CAA remains to be fully elucidated. In this review, we summarize the epidemiology, pathology, clinical and radiological features, and perspectives for future research directions in CAA therapeutics. Recent advances in mass spectrometric methodology combined with vascular isolation techniques have aided understanding of the cerebrovascular proteome. In this paper, we describe several potential key CAA-associated molecules that have been identified by proteomic analyses (apolipoprotein E, clusterin, SRPX1 (sushi repeat-containing protein X-linked 1), TIMP3 (tissue inhibitor of metalloproteinases 3), and HTRA1 (HtrA serine peptidase 1)), and their pivotal roles in Aβ cytotoxicity, Aβ fibril formation, and vessel wall remodeling. Understanding the interactions between cerebrovascular Aβ deposits and molecules that accumulate with Aβ may lead to discovery of effective CAA therapeutics and to the identification of biomarkers for early diagnosis.

Perfusion-weighted MRI in cerebral amyloid angiopathy-related transient focal neurological episodes

INTRODUCTION

Sporadic cerebral amyloid angiopathy (CAA) is a common age-related cerebral small vessel disease characterized by progressive ß-amyloid deposition in the walls of small cortical arteries, arterioles, and capillaries in the cerebral cortex and overlying leptomeninges. CAA-related transient focal neurological episodes (CAA-TFNEs) represent a challenging clinical feature interesting from a pathophysiological point of view.

CASE REPORT

Here we present two cases of CAA-TFNEs in which we performed functional imaging with perfusion-weighted imaging MR and brain 18 F-FDG PET. In both cases, we found a topographic relationship between the involved cortical areas and the clinical expression of CAA-TFNEs. Cortical superficial siderosis in the first case and a convexity subarachnoid hemorrhage in the second case were found in the contralateral rolandic area corresponding to the clinical symptoms. The same areas showed a reduction of rCBV and rCBF on perfusion-weighted MR and were also associated in one case with hypometabolism on 18 F-FDG PET.

DISCUSSION

These new findings strengthen the hypothesis that CAA involves the superficial leptomeningeal arteries but also the short penetrating arterioles reaching different depths in the cortex generating hypoperfusion and altered vascular reactivity and consequently reduced neuronal activity.

CONCLUSION

Understanding CAA-TFNEs is pivotal because they carry a very high risk of subsequent lobar intracerebral hemorrhage but are frequently misdiagnosed as TIAs and treated with antithrombotics enhancing the bleeding risk associated with CAA.

Highly sensitive T1-T2dual-mode MRI probe based on ultra-small gadolinium oxide-decorated iron oxide nanocrystals

Single-mode magnetic resonance imaging (MRI) contrast agents (CAs) in clinical settings are easily disturbed by calcification, bleeding, and adipose signals, which result in inaccurate diagnoses. In this study, we developed a highly efficient T₁-T₂dual-mode MRI CA using an ultra-small gadolinium oxide-decorated magnetic iron oxide nanocrystal (GMIO). The gadolinium element could effectively alter the magnetic properties of the GMIO from soft-ferromagnetism to superparamagnetism. In addition, when the Gd/Fe ratio was 15 % (designated as GMIO-2), the GMIO-2 possessed the best superparamagnetism and highest magnetism. Subsequently, T₁and T₂values of GMIO-2 were measured through a series of turbo spin-echo images and then multi-spin echo (MSE) sequence, respectively. Based on this, T₁and T₂relaxivities of GMIO-2 were calculated and were the highest (r₁: 1.306 m M^-1s^-1and r₂: 234.5 m M^-1s^-1) when compared to other groups. The cytotoxicity of GMIO-2 was negligible under a wide range of dosages, thus exhibiting excellent cell biocompatibility. Moreover, GMIO-2 could quickly diffuse into cells, leading to its effective accumulation. The systemic delivery of GMIO-2 resulted in an excellent T₁-T₂dual-mode MRI contrast effect in kidneys, which is expected to improve the diagnosis of kidney lesions. Therefore, this work provides a promising candidate for the development of a T₁-T₂dual-mode MRI CA.

Neuroimaging of Acute Intracerebral Hemorrhage

Intracerebral hemorrhage (ICH) accounts for 10% to 20% of all strokes worldwide and is associated with high morbidity and mortality. Neuroimaging is clinically important for the rapid diagnosis of ICH and underlying etiologies, but also for identification of ICH expansion, often as-sociated with an increased risk for poor outcome. In this context, rapid assessment of early hema-toma expansion risk is both an opportunity for therapeutic intervention and a potential hazard for hematoma evacuation surgery. In this review, we provide an overview of the current literature surrounding the use of multimodal neuroimaging of ICH for etiological diagnosis, prediction of early hematoma expansion, and prognostication of neurological outcome. Specifically, we discuss standard imaging using computed tomography, the value of different vascular imaging modalities to identify underlying causes and present recent advances in magnetic resonance imaging and computed tomography perfusion.

Neuropathological correlates of cortical superficial siderosis in cerebral amyloid angiopathy

Cortical superficial siderosis is an established haemorrhagic neuroimaging marker of cerebral amyloid angiopathy. In fact, cortical superficial siderosis is emerging as a strong independent risk factor for future lobar intracerebral haemorrhage. However, the underlying neuropathological correlates and pathophysiological mechanisms of cortical superficial siderosis remain elusive. Here we use an in vivo MRI, ex vivo MRI, histopathology approach to assess the neuropathological correlates and vascular pathology underlying cortical superficial siderosis. Fourteen autopsy cases with cerebral amyloid angiopathy (mean age at death 73 years, nine males) and three controls (mean age at death 91 years, one male) were included in the study. Intact formalin-fixed cerebral hemispheres were scanned on a 3 T MRI scanner. Cortical superficial siderosis was assessed on ex vivo gradient echo and turbo spin echo MRI sequences and compared to findings on available in vivo MRI. Subsequently, 11 representative areas in four cases with available in vivo MRI scans were sampled for histopathological verification of MRI-defined cortical superficial siderosis. In addition, samples were taken from predefined standard areas of the brain, blinded to MRI findings. Serial sections were stained for haematoxylin and eosin and Perls' Prussian blue, and immunohistochemistry was performed against amyloid-β and GFAP. Cortical superficial siderosis was present on ex vivo MRI in 8/14 cases (57%) and 0/3 controls (P = 0.072). Histopathologically, cortical superficial siderosis corresponded to iron-positive haemosiderin deposits in the subarachnoid space and superficial cortical layers, indicative of chronic bleeding events originating from the leptomeningeal vessels. Increased severity of cortical superficial siderosis was associated with upregulation of reactive astrocytes. Next, cortical superficial siderosis was assessed on a total of 65 Perls'-stained sections from MRI-targeted and untargeted sampling combined in cerebral amyloid angiopathy cases. Moderate-to-severe cortical superficial siderosis was associated with concentric splitting of the vessel wall (an advanced form of cerebral amyloid angiopathy-related vascular damage) in leptomeningeal vessels (P < 0.0001), but reduced cerebral amyloid angiopathy severity in cortical vessels (P = 0.048). In terms of secondary tissue injury, moderate-to-severe cortical superficial siderosis was associated with the presence of microinfarcts (P = 0.025), though not microbleeds (P = 0.973). Collectively, these data suggest that cortical superficial siderosis on MRI corresponds to iron-positive deposits in the superficial cortical layers, representing the chronic manifestation of bleeding episodes from leptomeningeal vessels. Cortical superficial siderosis appears to be the result of predominantly advanced cerebral amyloid angiopathy of the leptomeningeal vessels and may trigger secondary ischaemic injury in affected areas.

Intracerebral Hemorrhage Recurrence in Patients with and without Cerebral Amyloid Angiopathy

Background

Intracerebral hemorrhage (ICH) recurrence risk is known to be higher in patients with cerebral amyloid angiopathy (CAA) as compared to other causes of ICH. Risk factors for ICH recurrence are not completely understood, and our goal was to study specific imaging microangiopathy markers.

Methods

Retrospective case-control study of patients with non-traumatic ICH admitted to a single center between 2014 and 2017 who underwent magnetic resonance imaging (MRI). Clinical characteristics of the index event and occurrence of death and ICH recurrence were collected from clinical records. MRI images were independently reviewed by 2 neuroradiologists. Groups of patients with CAA-related and CAA-unrelated ICH defined were compared. Presence of CAA was defined according to the Boston modified criteria. Survival analysis with Kaplan-Meier curves and Cox-regression analyses was performed to analyze ICH recurrence-free survival.

Results

Among 448 consecutive patients with non-traumatic ICH admitted during the study period, 104 were included in the study, mean age 64 years (±13.5), median follow-up of 27 months (interquartile range, IQR 16–43), corresponding to 272 person-years of total follow-up. CAA-related ICH patients presented higher burden of lobar microbleeds (p < 0.001), higher burden of enlarged perivascular spaces (EPVS) in centrum semiovale (p < 0.001) and more frequently presented cortical superficial siderosis (cSS; p < 0.001). ICH recurrence in patients with CAA was 12.7 per 100 person-years, and no recurrence was observed in patients without CAA. Variables associated with ICH recurrence in the whole population were age (hazard ratio [HR] per 1-year increment = 1.05, 95% CI 1.00–1.11, p = 0.046), presence of disseminated cSS (HR 3.32, 95% CI 1.09–10.15, p = 0.035) and burden of EPVS in the centrum semiovale (HR per 1-point increment = 1.80, 95% CI 1.04–3.12, p = 0.035).

Conclusions

This study confirms a higher ICH recurrence risk in patients with CAA-related ICH and suggests that age, disseminated cSS, and burden of EPVS in the centrum semiovale are associated with ICH recurrence.

Imaging of vascular cognitive impairment

Vascular cognitive impairment (VCI) is a major health challenge and represents the second most common cause of dementia. We review the updated imaging classification and imaging findings of different subtypes of VCI. We will focus on the magnetic resonance imaging (MRI) markers of each subtype and highlight the role of advanced MR imaging sequences in the evaluation of these patients. Small vessel dementia appears as white matter hyperintensity, lacunae, microinfarcts, and microbleeds. Large vessel dementia includes strategic infarction and multi-infarction dementias. Hypoperfusion dementia can be seen as watershed infarcts and cortical laminar necrosis. Hemorrhagic dementia results from cerebral amyloid angiopathy and cortical superficial siderosis. Hereditary forms of VCI, caused by gene mutations such as CADASIL, should be suspected when dementia presents in young patients. Mixed dementia is seen in patients with Alzheimer's disease and the coexistence of cerebrovascular disease.