Mixed-location cerebral hemorrhage/microbleeds: Underlying microangiopathy and recurrence risk

Clinical usefulness of Edinburgh CT criteria in patients with lobar intracerebral hemorrhage

Background

Identifying the cause of intracerebral hemorrhage (ICH) is relevant to optimize its management. We aimed to assess the applicability and utility of the Edinburgh CT criteria for cerebral amyloid angiopathy (CAA) in an unselected cohort of hospitalized patients.

Patients and Methods

We retrospectively applied the Edinburgh criteria to the first available brain CTs of patients hospitalized for a first-ever lobar ICH in the district of L'Aquila from 2011 to 2017. ICH characteristics and outcomes were compared according to the presence of the Edinburgh CT criteria, including associated subarachnoid hemorrhage (aSAH) and finger-like projections (FLPs). The outcome of ICH in-hospital mortality was assessed with multivariate logistic regression analysis. We adopted the Edinburgh criteria, age, NIHSS and Glasgow Coma Scale scores, systolic blood pressure, antiplatelet treatment, ICH volume, and intraventricular extension on admission as covariates.

Results

Of 178 patients with lobar ICH, 52 (29.2%) had aSAH+FLPs, 60 (33.7%) aSAH only, 1 (0.6%) FLPs, and 65 (36.5%) none. Patients with aSAH+FLPs were older (79.0 ± 9.2 years) than those with only one criterion or none (74.0 ± 15.3 and 72.2 ± 13.8 years, respectively; P = 0.020). Patients with aSAH+FLPs also had more severe ICH at onset, higher in-hospital case-fatality (log rank test P = 0.003) and higher mRS scores at discharge (P < 0.001) as compared to those fulfilling one or none of the Edinburgh criteria. Low Glasgow Coma Scale score was the only factor independently associated to in-hospital case-fatality (odds ratio per point increase 0.51; 95% confidence interval, 0.32-0.91; P = 0.021).

Discussion

Our data suggest the applicability of the Edinburgh CT criteria in a hospital setting. The presence of those criteria reflects ICH clinical severity.

Conclusions

Applying the Edinburgh CT criteria might help refining the diagnosis and improving the management of patients with lobar ICH.

Cerebral Amyloid Angiopathy Presenting as Massive Subarachnoid Haemorrhage: A Case Study and Review of Literature

Cerebral amyloid angiopathy (CAA) is characterised by the progressive accumulation of β-amyloid (Aβ) in the walls of cerebral capillaries and arteries representing a major cause of haemorrhagic stroke including lobar intracerebral haemorrhage (ICH) and convexity subarachnoid haemorrhage (SAH). Haemorrhaging from CAA predominantly involves smaller arteries rather than arterial aneurysm. Restricted bleeding into the subarachnoid space in CAA results in asymptomatic or mild symptomatic SAH. Herein, we present an autopsied case of massive SAH related to CAA. An 89-year-old male with a history of mild Alzheimer’s disease (AD) and advanced pancreatic cancer with liver metastasis developed sudden onset of coma. Head CT illustrated ICH located in the right frontal lobe and right insula, as well as SAH bilaterally spreading from the basal cistern to the Sylvian fissure, with hydrocephalus and brain herniation. He died about 24 h after onset and the post-mortem examination showed no evidence of arterial aneurysm. The substantial accumulation of Aβ in the vessels around the haemorrhagic lesions led to the diagnosis of ICH related to CAA and secondary SAH, which may have been aggravated by old age and malignancy. This case suggests that CAA can cause severe SAH resembling aneurysmal origin and thus may be overlooked when complicated by atypical cerebral haemorrhage.

Blood Pressure and Outcomes in Patients With Different Etiologies of Intracerebral Hemorrhage: A Multicenter Cohort Study

Background We aimed to investigate the association between blood pressure (BP) and outcomes in intracerebral hemorrhage (ICH) subtypes with different etiologies. Methods and Results A total of 5656 in-hospital patients with spontaneous ICH were included between January 2012 and December 2016 in a prospective multicenter cohort study. Etiological subtypes of ICH were assigned using SMASH-U (structural lesion, medication, amyloid angiopathy, systemic/other disease, hypertension, undetermined) classification. Elevated systolic BP was defined as ≥140 mm Hg. Hypertension was defined as elevated BP for >1 month before the onset of ICH. The primary outcomes were measured as 1-month survival rate and 3-month mortality. A total of 5380 patients with ICH were analyzed, of whom 4052 (75.3%) had elevated systolic BP on admission and 3015 (56.0%) had hypertension. In multinomial analysis of patients who passed away by 3 months, systolic BP on admission was significantly different in cerebral amyloid angiopathy (P<0.001), structural lesion (P<0.001), and undetermined subtypes (P=0.003), compared with the hypertensive angiopathy subtype. Elevated systolic BP was dose-responsively associated with higher 3-month mortality in hypertensive angiopathy (Ptrend=0.013) and undetermined (Ptrend=0.005) subtypes. In cerebral amyloid angiopathy, hypertension history had significant inverse association with 3-month mortality (adjusted odds ratio, 0.37, 95% CI, 0.20-0.65; P<0.001). Similarly, adjusted Cox regression indicated decreased risk of 1-month survival rate in the presence of hypertension in patients with cerebral amyloid angiopathy (adjusted hazard ratio, 0.47; 95% CI, 0.24-0.92; P=0.027). Conclusions This study suggests that the association between BP and ICH outcomes might specifically depend on its subtypes, and cerebral amyloid angiopathy might be pathologically distinctive from the others. Future studies of individualized BP-lowering strategy are needed to validate our findings.

Association of Cerebral Small Vessel Disease and Cognitive Decline After Intracerebral Hemorrhage

OBJECTIVE

To determine whether MRI-based cerebral small vessel disease (CSVD) burden assessment, in addition to clinical and CT data, improved prediction of cognitive impairment after spontaneous intracerebral hemorrhage (ICH).

METHODS

We analyzed data from ICH survivors enrolled in a single-center prospective study. We employed 3 validated CSVD burden scores: global, cerebral amyloid angiopathy (CAA)-specific, and hypertensive arteriopathy (HTNA)-specific. We quantified cognitive performance by administering the modified Telephone Interview for Cognitive Status test. We utilized linear mixed models to model cognitive decline rates, and survival models for new-onset dementia. We calculated CSVD scores' cutoffs to maximize predictive performance for dementia diagnosis.

RESULTS

We enrolled 612 ICH survivors, and followed them for a median of 46.3 months (interquartile range 35.5-58.7). A total of 214/612 (35%) participants developed dementia. Higher global CSVD scores at baseline were associated with faster cognitive decline (coefficient -0.25, standard error [SE] 0.02) and dementia risk (sub-hazard ratio 1.35, 95% confidence interval 1.10-1.65). The global score outperformed the CAA and HTNA scores in predicting post-ICH dementia (all p < 0.05). Compared to a model including readily available clinical and CT data, inclusion of the global CSVD score resulted in improved prediction of post-ICH dementia (area under the curve [AUC] 0.89, SE 0.02 vs AUC 0.81, SE 0.03, p = 0.008 for comparison). Global CSVD scores ≥2 had highest sensitivity (83%) and specificity (91%) for dementia diagnosis.

CONCLUSIONS

A validated MRI-based CSVD score is associated with cognitive performance after ICH and improved diagnostic accuracy for predicting new onset of dementia.

Carotid intima-media thickness relative to cognitive impairment in dialysis patients, and their relationship with brain volume and cerebral small vessel disease

Background:

Carotid intima–media thickness (cIMT) is considered a risk factor for and predictor of cerebrovascular disease. In this study, we explored the contribution of cIMT to cognitive impairment (CI) in dialysis patients and the role of cerebral small vascular disease (CSVD) and brain atrophy in this process.

Methods:

Cognitive function was assessed using a comprehensive cognitive test battery. CSVD and brain volume were assessed by magnetic resonance imaging, and cIMT was measured by ultrasonography. Multivariable analysis and mediation were used to explore the relevant relationships among cIMT, CI, CSVD and brain volume.

Results:

Seventy-three dialysis patients were enrolled. Approximately 54.8% were diagnosed with increased cIMT. The increased cIMT group was older and had lower serum albumin and creatinine levels than the normal cIMT group. There was no difference in the CSVD prevalence between the different cIMT groups. Patients in the normal, unilaterally and bilaterally increased cIMT subgroups demonstrated a gradual decrease in brain-matter volume and degenerate cognitive function. cIMT was related to cognitive function and gray-/white-matter volume. Increased cIMT was associated with a significantly increased risk of a reduced Mini Mental State Examination/Montreal Cognitive Assessment score and Trail A/B time delay. Mediation analysis showed that CI was mediated by brain-matter volume but not by CSVD.

Conclusion:

Increased cIMT was an independent risk factor for impairment of global cognitive function, memory, and executive function. The impact of cIMT on cognition was not induced by CSVD but by brain atrophy. cIMT may be a useful tool for screening patients at high risk of CI in the dialysis population.

Intracerebral haemorrhage, microbleeds and antithrombotic drugs

Antithrombotic therapy is a cornerstone for secondary prevention of ischaemic events, cerebral and extra-cerebral. A number of clinical questions remain unanswered concerning the impact of antithrombotic drugs on the risk of first-ever and recurrent macro or micro cerebral haemorrhages, raising the clinical dilemma on the risk/benefit balance of giving antiplatelets and anticoagulants in patients with potential high risk of brain bleeds. High field magnetic resonance imaging (MRI) blood-weighted sequences, including susceptibility weighted imaging (SWI), have expanded the spectrum of these clinical questions, because of their increasing sensitivity in detecting radiological markers of small vessel disease. This review will summarise the literature, focusing on four main clinical questions: how do cerebral microbleeds impact the risk of cerebrovascular events in healthy patients, in patients with previous ischaemic stroke or transient ischaemic attack, and in patients with intracerebral haemorrhage? Is the risk/benefit balance of oral anticoagulants shifted by the presence of microbleeds in patients with atrial fibrillation after recent ischaemic stroke or transient ischaemic attack? Should we restart antiplatelet drugs after symptomatic intracerebral haemorrhage or not? Are oral anticoagulants allowed in patients with a history of atrial fibrillation and previous intracerebral haemorrhage?

Asymptomatic Striatocapsular slit-like Hemorrhage as a Severity Marker in Patients with Hypertensive Angiopathy

BACKGROUND

Concomitant asymptomatic striatocapsular slit-like hemorrhage (SSH) is occasionally found in patients of spontaneous intracerebral hemorrhage (ICH), but was seldomly described in the literature. In this study, we described the clinico-radiological features of asymptomatic SSH in ICH patients with hypertensive microangiopathy.

METHODS AND RESULTS

246 patients with strictly deep or mixed deep and lobar ICH/microbleeds were included. SSH was defined as hypointense lesions involving the lateral aspect of lentiform nucleus or external capsule in slit shape (>1.5 cm) on susceptibility-weighted imaging without history of associated symptoms. Demographics and neuroimaging markers were compared between patients with SSH and those without. Patients with SSH (n=24, 10%) and without SSH had comparable age (62.0 ± 12.6 vs. 62.3 ± 13.5, p = 0.912) and vascular risk factor profiles including the diagnosis of chronic hypertension, diabetes, and dyslipidemia (all p>0.05). SSH was associated with more common lobar microbleeds (79.2% vs 48.2%, p = 0.005), lacunes (75% vs. 41.4%, p = 0.002) and higher white matter hyperintensity (WMH) volumes (24.1 [10.4-46.3] vs. 13.9 [7.0-24.8] mL, p = 0.012) on MRI, as well as more frequent left ventricular hypertrophy (LVH) (50.0% vs. 20.5%, p = 0.004) and albuminuria (41.7% vs. 19.4%, p = 0.018). In multivariable analyses, SSH remains independently associated with LVH (p = 0.017) and albuminuria (p = 0.032) after adjustment for age, sex, microbleed, lacune and WMH volume.

CONCLUSIONS

Asymptomatic SSH is associated with more severe cerebral small vessel disease-related change on brain MRI, and hypertensive cardiac and renal injury, suggesting a more advanced stage of chronic hypertension.

Clinical and radiological differences between patients with probable cerebral amyloid angiopathy and mixed cerebral microbleeds

BACKGROUND

The key imaging features of cerebral amyloid angiopathy (CAA) are lobar, cortical, or cortico-subcortical microbleeds, macrohaemorrhages and cortical superficial siderosis (cSS). In contrast, hypertensive angiopathy is characterized by (micro) haemorrhages in the basal ganglia, thalami, periventricular white matter or the brain stem. Another distinct form of haemorrhagic microangiopathy is mixed cerebral microbleeds (mixed CMB) with features of both CAA and hypertensive angiopathy. The distinction between the two entities (CAA and mixed CMB) is clinically relevant because the risk of haemorrhage and stroke should be well balanced if oral anticoagulation is indicated in CAA patients. We aimed to comprehensively compare these two entities.

METHODS

Patients with probable CAA according to the modified Boston criteria and mixed CMB without macrohaemorrhage were retrospectively identified from our database. Comprehensive comparison regarding clinical and radiological parameters was performed between the two cohorts.

RESULTS

Patients with CAA were older (78 ± 8 vs. 74 ± 9 years, p = 0.036) and had a higher prevalence of cSS (19% vs. 4%, p = 0.027) but a lower prevalence of lacunes (73% vs. 50%, p = 0.018) and deep lacunes (23% vs. 51%, p = 0.0003) compared to patients with mixed CMB. Logistic regression revealed an association between the presence of deep lacunes and mixed CMB. The other collected parameters did not reveal a significant difference between the two groups.

CONCLUSIONS

CAA and mixed CMB demonstrate radiological differences in the absence of macrohaemorrhages. However, more clinically available biomarkers are needed to elucidate the contribution of CAA and hypertensive angiopathy in mixed CMB patients.

Risk factors for intracerebral haemorrhage - Results from a prospective population-based study

Introduction

While the relationship between hypertension and incident intracerebral haemorrhage is well established, other risk factors are less clear. This study examined risk factors for primary intracerebral haemorrhage, separately for lobar and non-lobar intracerebral haemorrhage.

Patients and methods

Incidence of intracerebral haemorrhage was studied among 28,416 individuals from the population-based Malmö Diet and Cancer cohort. Intracerebral haemorrhage cases were ascertained using the Swedish Hospital Discharge Register and the Stroke Register of Malmö, validated by review of hospital records and images, and classified by location by a neuroradiologist. Multivariable Cox regression was used.

Results

Three hundred and thirty-three intracerebral haemorrhages occurred, mean follow-up time was 18.4 years. Systolic blood pressure (hazard ratio per 10 mmHg 1.19 [95% confidence interval 1.13–1.26], diastolic blood pressure (hazard ratio 1.42 [1.27–1.59]), oral anticoagulants (hazard ratio 4.26 [2.17–8.38]), smoking (hazard ratio 1.45 [1.14–1.87]), living alone (hazard ratio 1.32 [1.04–1.69]) and low apolipoprotein B (hazard ratio per 10 mg/dL: 0.94 [0.90–0.99]) were significantly associated with incident intracerebral haemorrhage after multivariable adjustment. Systolic blood pressure, smoking and oral anticoagulants were associated with lobar intracerebral haemorrhage. Systolic blood pressure, diastolic blood pressure, living alone and diabetes were associated with non-lobar intracerebral haemorrhage. Diabetes and diastolic blood pressure showed significantly different relationships with lobar and non-lobar intracerebral haemorrhage. Alcohol, apolipoprotein A1, body mass index, waist circumference, physical activity and education were not independently associated with intracerebral haemorrhage.

Discussion and conclusions: Blood pressure, smoking, low apolipoprotein B, oral anticoagulants and living alone were associated with intracerebral haemorrhage. Diabetes was associated with non-lobar intracerebral haemorrhage only. Further research is required on differences between lobar and non-lobar intracerebral haemorrhage.

Clinical Features and Experimental Models of Cerebral Small Vessel Disease

Cerebral small vessel disease (SVD) refers to a group of disease conditions affecting the cerebral small vessels, which include the small arteries, arterioles, capillaries, and postcapillary venules in the brain. SVD is the primary cause of vascular cognitive impairment and gait disturbances in aged people. There are several types of SVD, though arteriolosclerosis, which is mainly associated with hypertension, aging, and diabetes mellitus, and cerebral amyloid angiopathy (CAA) comprise most SVD cases. The pathology of arteriolosclerosis-induced SVD is characterized by fibrinoid necrosis and lipohyalinosis, while CAA-associated SVD is characterized by progressive deposition of amyloid beta (Aβ) protein in the cerebral vessels. Brain magnetic resonance imaging (MRI) has been used for examination of SVD lesions; typical lesions are characterized by white matter hyperintensity, lacunar infarcts, enlargement of perivascular spaces (EPVS), microbleeds, cortical superficial siderosis (cSS), and cortical microinfarcts. The microvascular changes that occur in the small vessels are difficult to identify clearly; however, these consequent image findings can represent the SVD. There are two main strategies for prevention and treatment of SVD, i.e., pharmacotherapy and lifestyle modification. In this review, we discuss clinical features of SVD, experimental models replicating SVD, and treatments to further understand the pathological and clinical features of SVD.

Contrast leakage distant from the hematoma in patients with spontaneous ICH: A 7 T MRI study

Disruption of the blood-brain barrier (BBB) might play a role in the pathophysiology of cerebral small vessel disease-related ICH. The aim of this study was to assess presence and extent of contrast agent leakage distant from the hematoma as a marker of BBB disruption in patients with spontaneous ICH. We prospectively performed 7 tesla MRI in adult patients with spontaneous ICH and assessed contrast leakage distant from the hematoma on 3D FLAIR images. Thirty-one patients were included (mean age 60 years, 29% women). Median time between ICH and MRI was 20 days (IQR 9-67 days). Seventeen patients (54%; seven lobar, nine deep, one infratentorial ICH) had contrast leakage, located cortical in 16 and cortical and deep in one patient. Patients with contrast leakage more often had lobar cerebral microbleeds (CMBs; 77%) than those without (36%; RR 2.5, 95% CI 1.1-5.7) and a higher number of lobar CMBs (patients with contrast leakage: median 2, IQR 1-8 versus those without: median 0, IQR 0-2; p = 0.02). This study shows that contrast leakage distant from the hematoma is common in days to weeks after spontaneous ICH. It is located predominantly cortical and related to lobar CMBs and therefore possibly to cerebral amyloid angiopathy.

In utero exposure to the Great Chinese Famine and risk of intracerebral hemorrhage in midlife

OBJECTIVE

To investigate whether in utero exposure to the Great Chinese Famine in 1959 to 1961 was associated with risk of intracerebral hemorrhage (ICH) in adulthood.

METHODS

In this cohort analysis, we included 97,399 participants of the Kailuan Study who were free of cardiovascular disease and cancer at baseline (2006). Cases of incident ICH were confirmed by medical record review. We used the Cox proportional hazards model to calculate the hazard ratio (HR) and 95% confidence interval (CI) for ICH according to in utero famine exposure status.

RESULTS

Among 97,399 participants in the current analyses, 6.3% (n = 6,160) had been prenatally exposed to the Great Chinese Famine. During a median 9.0 years of follow-up (2006-2015), we identified 724 cases of incident ICH. After adjustment for potential confounders, the HR of ICH was 1.99 (95% CI 1.39-2.85) for in utero famine-exposed individuals vs individuals who were not exposed to the famine. When exposure to famine and severity of famine were examined jointly, the adjusted HR was 2.99 (95% CI 1.21-7.39) for in utero exposure to severe famine and 1.94 (95% CI 1.32-2.84) for in utero exposure to less severe famine relative to those without exposure to famine.

CONCLUSIONS

Individuals with in utero exposure to famine, especially those exposed to severe famine, were more likely to have ICH in midlife, highlighting the role of nutritional factors in susceptibility to this severe cerebral condition.

Cerebral Microbleeds and Chronic Kidney Disease in Acute Ischemic Stroke Patients with Atrial Fibrillation

BACKGROUND

Cerebral microbleeds (CMBs) are associated with the risk of intracerebral hemorrhage in stroke patients with atrial fibrillation (AF). We investigated the association between CMBs and chronic kidney disease (CKD) in patients with acute ischemic stroke and AF.

METHODS

We retrospectively examined consecutive patients with acute ischemic stroke and AF who underwent brain gradient-echo T2*-weighted magnetic resonance imaging. The number and distribution (lobar, deep or infratentorial, and mixed) of CMBs were assessed. Kidney function was assessed according to the estimated glomerular filtration rate (eGFR), which was calculated using a modified version of the Modification of Diet in Renal Disease equation.

RESULTS

Of the 357 included patients, 105 (29.4%) had CMBs. CKD (eGFR < 60 mL/min/1.73 m²) was found in 131 (36.7%) patients. Patients with CKD showed a higher prevalence of any form of CMB (41.2% versus 22.6%, P < .001), deep or infratentorial CMBs (19.9% versus 9.3%, P < .01), and mixed CMBs (14.5% versus 5.3%, P < .01) than those without CKD. After adjusting for age and other confounding factors, CKD was found to be independently associated with the presence of any form of CMB (odds ratio 1.89, P = .02) and mixed CMBs (odds ratio 3.10, P < .01). Moreover, moderate to severe CKD (eGFR < 45 mL/min/1.73 m²) was independently associated with the presence of multiple CMBs (odds ratio 2.31, P = .04).

CONCLUSIONS

CMBs and CKD are common in acute ischemic stroke patients with AF, and CKD may be a risk factor for CMBs. Further longitudinal studies are needed to evaluate whether maintaining kidney function can prevent the development of CMBs.

Microbleeds and Medial Temporal Atrophy Determine Cognitive Trajectories in Normal Aging: A Longitudinal PET-MRI Study

BACKGROUND

The cognitive trajectories in normal aging may be affected by medial temporal atrophy (MTA) and amyloid burden, as well as vascular pathologies such as cortical microbleeds (CMB) and white matter hyperintensities (WMH).

OBJECTIVE

We addressed here the role of imaging markers in their prediction in a real-world situation.

METHODS

We performed a 4.5-year longitudinal study in 90 older community-dwellers coupling two neuropsychological assessments, MTA estimated with the Schelten's scale, number of CMB, and WMH evaluated with the Fazekas score at inclusion and follow-up, visual rating of amyloid PET and glucose hypometabolism at follow-up, and APOE genotyping. Regression models were built to explore the association between the continuous cognitive score (CCS) and imaging parameters.

RESULTS

The number of strictly lobar CMB at baseline (4 or more) was related to a 5.5-fold increase of the risk of cognitive decrement. This association persisted in multivariable models explaining 10.6% of the CCS decrease variance. MTA, and Fazekas score at baseline and amyloid positivity or abnormal FDG PET, were not related to the cognitive outcome. The increase of right MTA at follow-up was the only correlate of CCS decrease both in univariate and multivariable models explaining 9.2% of its variance.

CONCLUSION

The present data show that the accumulation of more than four CMB is associated with significant cognitive decrement over time in highly educated elderly persons. They also reveal that the progressive deterioration of cognitive performance within the age-adjusted norms is also related to the increase of visually assessed MTA.

Hypertensive Arteriopathy and Cerebral Amyloid Angiopathy in Patients with Cognitive Decline and Mixed Cerebral Microbleeds

BACKGROUND

Hypertensive arteriopathy (HA) and cerebral amyloid angiopathy (CAA) may contribute to the development of mixed cerebral microbleeds (CMBs). Recently, the total small vessel disease (SVD) scores for HA and CAA were proposed, which are determined by a combination of MRI markers to reflect overall severity of these microangiopathies.

OBJECTIVE

We investigated whether or not total HA-SVD and CAA-SVD scores could be used to predict overlap of HA and CAA in patients with mixed CMBs.

METHODS

Fifty-three subjects with mixed CMBs were retrospectively analyzed. MRI markers (CMBs, lacunes, perivascular space, white matter hyperintensity [WMH] and cortical superficial siderosis [cSS]) were assessed. The HA-SVD score and CAA-SVD score were obtained for each subject. Anterior or posterior WMH was also assessed using the age-related white matter changes scale.

RESULTS

The two scores were positively correlated (ρ= 0.449, p < 0.001). The prevalence of lobar dominant CMB distribution (p < 0.001) and lacunes in the centrum semiovale (p < 0.001) and the severity of WMH in the parieto-occipital lobes (p = 0.004) were significantly higher in the high CAA-SVD score group. cSS was found in four patients with high CAA-SVD score who showed lobar-dominant CMB distribution and severe posterior WMH.

CONCLUSION

Mixed CMBs are mainly due to HA. Assessing both two scores may predict the overlap of HA and CAA in individuals with mixed CMBs. Patients with a high CAA-SVD score may have some degree of advanced CAA, especially when lobar predominant CMBs, severe posterior WMH, lobar lacunes, or cSS are observed.

Superficial Cerebellar Microbleeds and Cerebral Amyloid Angiopathy

Background and Purpose—

The differentiation between cerebral amyloid angiopathy (CAA) and hypertensive small vessel disease in primary intracerebral hemorrhage is mainly based on hemorrhagic neuroimaging markers in the supratentorial regions, and the cause for cerebellar microbleeds remains unknown. Our aim was to investigate whether superficial cerebellar microbleeds are more likely to be related to CAA rather than hypertensive small vessel disease.

Methods—

Two hundred seventy-five consecutive patients with intracerebral hemorrhage were retrospectively reviewed from a prospectively maintained hospital-based stroke registry. Eighty-five (33.1%) patients had cerebellar microbleeds and were categorized into superficial (gray matter, vermis), deep (white matter, deep nucleus, cerebellar peduncle), or mixed type based on the location of cerebellar hemorrhagic lesions. Amyloid imaging was obtained using 11C-Pittsburgh Compound B–positron emission tomography in a subgroup of patients. The associations between cerebellar microbleed locations and the type of small vessel disease (CAA versus hypertensive small vessel disease) based on distribution of supratentorial hemorrhagic lesions as well as other magnetic resonance imaging and positron emission tomography markers were analyzed.

Results—

The presence of cerebellar microbleed was independently associated with supratentorial microbleed and lacunar infarcts (both P <0.01). Strictly superficial cerebellar microbleeds were significantly related to CAA–intracerebral hemorrhage, cortical superficial siderosis and high-grade enlarged perivascular space in centrum semiovale (all P <0.05); deep or mixed cerebellar microbleeds were related to hypertension and deep microbleed (all P <0.05). In multivariable models, superficial cerebellar microbleeds were independently associated with CAA–intracerebral hemorrhage ( P =0.03). Of 33 patients assessed by amyloid positron emission tomography, cerebral and cerebellar amyloid load (standardized uptake value ratio) was higher in patients with superficial cerebellar microbleeds compared with deep/mixed cerebellar microbleeds (cerebrum standardized uptake value ratio [reference: cerebellum] 1.33±0.24 versus 1.05±0.09, P <0.001; cerebellum standardized uptake value ratio [reference: pons] 0.58±0.08 versus 0.51±0.09, P =0.03).

Conclusions—

Patients with strictly superficial cerebellar microbleeds are associated with a clinicoradiological diagnosis of CAA as well as increased cerebral and cerebellar amyloid deposition on Pittsburgh Compound B–positron emission tomography, suggesting underlying CAA pathology.

Mixed-location cerebral microbleeds as a biomarker of neurodegeneration in a memory clinic population

Cerebral microbleeds (CMBs) in the lobar and deep locations are associated with two distinct pathologies: cerebral amyloid angiopathy and hypertensive arteriopathy. However, the role of mixed-location CMBs in neurodegeneration remains unexplored. We investigated the associations between strictly lobar, strictly deep and mixed-location CMBs with markers of neurodegeneration. This study recruited 477 patients from a memory clinic who underwent 3T MRI scans. CMBs were categorized into strictly lobar, strictly deep and mixed-location. Cortical thickness, white matter volume and subcortical structural volumes were quantified using Free-Surfer. Linear regression models were performed to assess the association between CMBs and cerebral atrophy, and the mean difference (β) and 95% confidence intervals (CIs) were reported. In the regression analyses, mixed-location CMBs were associated with smaller cortical thickness of limbic region [β= -0.01; 95% CI= -0.02, -0.00, p=0.007) as well as with smaller accumbens volume [β= -0.01; 95% CI= -0.02, -0.00, p=0.004) and presubiculum region of hippocampus [β= -0.01; 95% CI= -0.02, -0.00, p=0.002). Strictly lobar CMBs were associated with smaller total white matter volume [β= -0.03; 95% CI= -0.04, -0.01, p<0.001] and with region specific white matter volumes. The underlying mechanism requires further research and may involve shared mechanisms of vascular dysfunction and neurodegeneration.

Underlying Small Vessel Disease Associated With Mixed Cerebral Microbleeds

Background and Purpose: Whether patients with both lobar and deep cerebral microbleeds (mixed CMB) have advanced cerebral amyloid angiopathy (CAA), hypertensive angiopathy (HA) or both is uncertain. To get insight into the underlying small vessel disease (SVD) associated with mixed CMB, we explored its association with cortical superficial siderosis (cSS), a key marker of CAA and other MRI markers of SVD in patients with intracerebral hemorrhage (ICH).

Methods: Of 425 consecutive patients with acute ICH who had received brain MRIs, 260 had ≥1 CMB and were included in the analysis. They were categorized as strictly lobar CMB (suggesting CAA), strictly deep CMB (suggesting HA) or mixed CMB. Clinical and imaging characteristics were compared (1) between the three CMB groups and (2) within mixed CMB patients according to the symptomatic ICH location.

Results: Overall, 111 (26%) patients had mixed CMB. Compared to strictly lobar CMB (n = 111) and strictly deep CMB (n = 38), patients with mixed CMB had a more severe burden of lacune, white matter hyperintensities and CMB. cSS was observed in 24.3% of patients with mixed CMB compared to 44.1% in strictly lobar CMB and 10.5% in strictly deep CMB (p < 0.0001). Among patients with mixed CMB, 44 (39.6%) had a lobar symptomatic ICH and 67 (60.4%) had a non-lobar ICH. Patients with non-lobar ICH were more likely to have hypertension, whereas those with lobar ICH were more likely to have cSS and chronic lobar ICH and had higher ratio lobar CMB count/total CMB count.

Conclusions: Mixed CMB is frequently encountered in patients with ICH and appears as a heterogeneous group, suggesting that both CAA and HA may be contributing to mixed CMB. Neuroimaging markers including ICH location, cSS, and CMB distribution may indicate the predominant underlying vasculopathy, with potential prognostic implications.

Advancing diagnostic criteria for sporadic cerebral amyloid angiopathy: Study protocol for a multicenter MRI-pathology validation of Boston criteria v2.0

RATIONALE

The Boston criteria are used worldwide for the in vivo diagnosis of cerebral amyloid angiopathy and are the basis for clinical decision-making and research in the field. Given substantial advances in cerebral amyloid angiopathy's clinical aspects and MRI biomarkers, we designed a multicenter study within the International cerebral amyloid angiopathy Association aimed at further validating the diagnostic accuracy of the Boston and potentially improving and updating them.

AIM

We aim to derive and validate an updated "version 2.0" of the Boston criteria across the spectrum of cerebral amyloid angiopathy-related presentations and MRI biomarkers.

SAMPLE SIZE ESTIMATES

Participating centers with suitable available data (see Methods) were identified from existing collaborations and an open invitation to the International Cerebral Amyloid Angiopathy Association emailing list. Our study sample will include: (1) a derivation cohort - Massachusetts General Hospital (MGH), Boston cases from inception to 2012 (∼150 patients); (2) temporal external validation cohort - MGH, Boston cases from 2012 to 2018 (∼100 patients); and (3) geographical external validation cohort - non-Boston cases (∼85 patients).

METHODS AND DESIGN

Multicenter collaborative study. We will collect and analyze data from patients' age ≥ 50 with any potential sporadic cerebral amyloid angiopathy-related clinical presentations (spontaneous intracerebral hemorrhage, transient focal neurological episodes and cognitive impairment), available brain MRI ("index test"), and histopathologic assessment for cerebral amyloid angiopathy ("reference standard" for diagnosis). Trained raters will assess MRI for all prespecified hemorrhagic and non-hemorrhagic small vessel disease markers of interest, according to validated criteria and a prespecified protocol, masked to clinical and histopathologic features. Brain tissue samples will be rated for cerebral amyloid angiopathy, defined as Vonsattel grade ≥2 for whole brain autopsies and ≥1 for cortical biopsies or hematoma evacuation. Based on our estimated available sample size, we will undertake pre-specified cohort splitting as above. We will: (a) pre-specify variables and statistical cut-offs; (b) examine univariable and multivariable associations; and (c) then assess classification measures (sensitivity, specificity etc.) for each MRI biomarker individually, in relation to the cerebral amyloid angiopathy diagnosis reference standard on neuropathology in a derivation cohort. The MRI biomarkers strongly associated with cerebral amyloid angiopathy diagnosis will be selected for inclusion in provisional (probable and possible cerebral amyloid angiopathy) Boston criteria v2.0 and validated using appropriate metrics and models.

STUDY OUTCOMES

Boston criteria v2.0 for clinical cerebral amyloid angiopathy diagnosis.

DISCUSSION

This work aims to potentially update and improve the diagnostic test accuracy of the Boston criteria for cerebral amyloid angiopathy and to provide wider validation of the criteria in a large sample. We envision that this work will meet the needs of clinicians and investigators and help accelerate progress towards better treatment of cerebral amyloid angiopathy.

Invited Review: The spectrum of age-related small vessel diseases: potential overlap and interactions of amyloid and nonamyloid vasculopathies

Deep perforator arteriopathy (DPA) and cerebral amyloid angiopathy (CAA) are the commonest known cerebral small vessel diseases (CSVD), which cause ischaemic stroke, intracebral haemorrhage (ICH) and vascular cognitive impairment (VCI). While thus far mainly considered as separate entities, we here propose that DPA and CAA share similarities, overlap and interact, so that 'pure' DPA or CAA are extremes along a continuum of age-related small vessel pathologies. We suggest blood-brain barrier (BBB) breakdown, endothelial damage and impaired perivascular β-amyloid (Aβ) drainage are hallmark common mechanisms connecting DPA and CAA. We also suggest a need for new biomarkers (e.g. high-resolution imaging) to deepen understanding of the complex relationships between DPA and CAA.

Mixed Small Vessel Disease in a Patient with Dementia with Lewy Bodies

Background: Cerebral amyloid angiopathy (CAA) is characterized by deposition of amyloid in small/medium size brain vessels, and may coexist with Alzheimer’s disease or dementia with Lewy bodies (DLB). We describe a patient with a clinical diagnosis of DLB and imaging/biochemical characteristics suggestive of mixed small vessel disease (both CAA and non-amyloid microangiopathy). Methods: Clinical evaluation according to recent diagnostic criteria, magnetic resonance imaging, dopamine-transporter scan (DAT-scan) and cerebrospinal fluid (CSF) analysis for dementia biomarkers were all performed. Results: The patient is a 71-year-old male, fulfilling criteria for probable DLB, with a positive DAT-scan, but with multiple microbleeds in a cortical-subcortical location suggestive of CAA, some microbleeds in deep brain nuclei suggestive of non-amyloid microangiopathy and abnormal levels of only amyloid-beta (Aβ₄₂) in CSF. Conclusion: Coexistent mixed vascular and neurodegenerative disorders are frequent in older subjects with dementia and each one of the underlying pathologies may contribute to, or modify the clinical presentation.

Cerebral microbleeds and stroke risk after ischaemic stroke or transient ischaemic attack: a pooled analysis of individual patient data from cohort studies

BACKGROUND

Cerebral microbleeds are a neuroimaging biomarker of stroke risk. A crucial clinical question is whether cerebral microbleeds indicate patients with recent ischaemic stroke or transient ischaemic attack in whom the rate of future intracranial haemorrhage is likely to exceed that of recurrent ischaemic stroke when treated with antithrombotic drugs. We therefore aimed to establish whether a large burden of cerebral microbleeds or particular anatomical patterns of cerebral microbleeds can identify ischaemic stroke or transient ischaemic attack patients at higher absolute risk of intracranial haemorrhage than ischaemic stroke.

METHODS

We did a pooled analysis of individual patient data from cohort studies in adults with recent ischaemic stroke or transient ischaemic attack. Cohorts were eligible for inclusion if they prospectively recruited adult participants with ischaemic stroke or transient ischaemic attack; included at least 50 participants; collected data on stroke events over at least 3 months follow-up; used an appropriate MRI sequence that is sensitive to magnetic susceptibility; and documented the number and anatomical distribution of cerebral microbleeds reliably using consensus criteria and validated scales. Our prespecified primary outcomes were a composite of any symptomatic intracranial haemorrhage or ischaemic stroke, symptomatic intracranial haemorrhage, and symptomatic ischaemic stroke. We registered this study with the PROSPERO international prospective register of systematic reviews, number CRD42016036602.

FINDINGS

Between Jan 1, 1996, and Dec 1, 2018, we identified 344 studies. After exclusions for ineligibility or declined requests for inclusion, 20 322 patients from 38 cohorts (over 35 225 patient-years of follow-up; median 1·34 years [IQR 0·19-2·44]) were included in our analyses. The adjusted hazard ratio [aHR] comparing patients with cerebral microbleeds to those without was 1·35 (95% CI 1·20-1·50) for the composite outcome of intracranial haemorrhage and ischaemic stroke; 2·45 (1·82-3·29) for intracranial haemorrhage and 1·23 (1·08-1·40) for ischaemic stroke. The aHR increased with increasing cerebral microbleed burden for intracranial haemorrhage but this effect was less marked for ischaemic stroke (for five or more cerebral microbleeds, aHR 4·55 [95% CI 3·08-6·72] for intracranial haemorrhage vs 1·47 [1·19-1·80] for ischaemic stroke; for ten or more cerebral microbleeds, aHR 5·52 [3·36-9·05] vs 1·43 [1·07-1·91]; and for ≥20 cerebral microbleeds, aHR 8·61 [4·69-15·81] vs 1·86 [1·23-1·82]). However, irrespective of cerebral microbleed anatomical distribution or burden, the rate of ischaemic stroke exceeded that of intracranial haemorrhage (for ten or more cerebral microbleeds, 64 ischaemic strokes [95% CI 48-84] per 1000 patient-years vs 27 intracranial haemorrhages [17-41] per 1000 patient-years; and for ≥20 cerebral microbleeds, 73 ischaemic strokes [46-108] per 1000 patient-years vs 39 intracranial haemorrhages [21-67] per 1000 patient-years).

INTERPRETATION

In patients with recent ischaemic stroke or transient ischaemic attack, cerebral microbleeds are associated with a greater relative hazard (aHR) for subsequent intracranial haemorrhage than for ischaemic stroke, but the absolute risk of ischaemic stroke is higher than that of intracranial haemorrhage, regardless of cerebral microbleed presence, antomical distribution, or burden.

FUNDING

British Heart Foundation and UK Stroke Association.

Role of Cerebral Microbleeds for Intracerebral Haemorrhage and Dementia

PURPOSE OF REVIEW

Cerebral microbleeds (CMB)-small round or ovoid lesions detected in hyposignal on blood-sensitive MRI sequences-are promising radiological biomarkers of cerebral small vessel disease. Their relations with ischaemic or haemorragic stroke and their potential contribution to dementia have been extensively addressed. This article reviews recent research on the clinical significance of CMB that remains to be determined.

RECENT FINDINGS

The presence, burden and location of CMB allow to obtain a more accurate estimate of intracerebral haemorrhage and ischaemic stroke risk. Most studies evaluating the association between CMB and dementia are hampered by methodological limitations and show conflicting results. CMB mainly reflect the severity of the underlying small vessel disease and should not be interpreted independently of the others neuroimaging biomarkers or the clinical setting. Future large prospective longitudinal studies and randomized controlled trials in various settings are required to determine whether specific therapies are beneficial in case of incidental findings.

Cerebellar Microbleed Distribution Patterns and Cerebral Amyloid Angiopathy

Background and Purpose- Hematoma location within the cerebellum may help identify the dominant small vessel disease type (cerebral amyloid angiopathy [CAA] versus nonamyloid small vessel disease). However, it is unknown whether this holds true for cerebral microbleeds (CMBs) within the cerebellum. We tested the hypothesis that cerebellar CMBs restricted to the cortex and vermis (defined as superficial regions) are associated with clinically diagnosed and pathology-verified CAA. Methods- Three hundred and seven consecutive spontaneous intracerebral hemorrhage (ICH) patients with a baseline magnetic resonance imaging that included susceptibility-weighted imaging or angiography were enrolled. Using a topographical template, cerebellar CMB patterns were defined as strictly superficial versus deep (cerebellar gray nuclei and white matter) or mixed (both regions involved). Thirty-six ICH patients with cerebellar CMBs and neuropathology data available were evaluated for the presence of CAA. Results- One hundred and thirty-five (44%) ICH patients had CMBs in the cerebellum. In the patient group with cerebellar CMBs, 85 (63%) showed a superficial pattern, and 50 (37%) had a deep/mixed pattern. Strictly superficial cerebellar CMBs were independently associated with a supratentorial pattern of probable CAA-ICH according to the Boston criteria (odds ratio, 1.6; CI, 1.03-2.5) and deep/mixed cerebellar CMBs with a pattern of deep/mixed ICH (odds ratio, 1.8; CI, 1.2-2.7). Pathologically verified CAA was present in 23 of 24 (96%) patients with superficial cerebellar CMBs versus 3 of 12 (25%) patients with deep/mixed cerebellar CMBs ( P<0.001). Conclusions- In ICH patients, cerebellar CMBs are relatively common and often restricted to superficial regions. A strictly superficial distribution of cerebellar CMBs is associated with clinically diagnosed and pathologically verified CAA.

Total Burden of Cerebral Small Vessel Disease in Recurrent ICH versus First-ever ICH

The relationship between recurrent intracerebral hemorrhage (ICH) and total burden of cerebral small vessel disease (CSVD) is not completely investigated. We aimed to study whether recurrent intracerebral hemorrhage (ICH) had higher CSVD score than first-ever ICH. Lacunes, white matter hyperintensities (WMH), cerebral microbleeds (CMBs), enlarged perivascular spaces (EPVS), cortical superficial siderosis (cSS) and CSVD score were rated on brain magnetic resonance imaging (MRI) in primary ICH patients. Recurrent ICHs were confirmed by reviewing the medical records and MRI scans. Mixed hematomas were defined as follows: deep + lobar, deep + cerebellar, or deep + lobar + cerebellar. Of the 184 patients with primary ICH enrolled (mean age, 61.0 years; 75.5% men), recurrent ICH was present in 45 (24.5%) patients; 26.1% (48/184) had ≥2 hematomas, 93.8% (45/48) of which exhibited recurrent ICH. Mixed hematomas were identified in 8.7% (16/184) of patients and bilateral hematomas in 17.9% (33/184). All mixed hematomas and bilateral hematomas were from cases of recurrent ICH. Patients with mixed etiology-ICH were more likely to have recurrent ICH than patients with cerebral amyloid angiopathy (CAA) or hypertensive angiopathy (HA)-related ICH (36.8% vs17.8%, p=0.008). Multivariate ordinal regression analysis showed that the presence of recurrent ICH (p=0.001), ≥2 hematomas (p=0.002), mixed hematomas (p<0.00001), and bilateral hematomas (p=0.002) were separately significantly associated with a high CSVD score. Recurrent ICH occurs mostly among patients with mixed etiology-ICH and is associated with a higher CSVD burden than first-ever ICH, which needs to be verified by future larger studies.

Advances in cerebral amyloid angiopathy imaging

Cerebral amyloid angiopathy (CAA) is a cerebral small vessel disease caused by β -amyloid (Aβ) deposition at the leptomeningeal vessel walls. It is a common cause of spontaneous intracerebral hemorrhage and a frequent comorbidity in Alzheimer’s disease. The high recurrent hemorrhage rate in CAA makes it very important to recognize this disease to avoid potential harmful medication. Imaging studies play an important role in diagnosis and research of CAA. Conventional computed tomography and magnetic resonance imaging (MRI) methods reveal anatomical alterations, and remains as the most reliable tool in identifying CAA according to modified Boston criteria. The vascular injuries of CAA result in both hemorrhagic and ischemic manifestations and related structural changes on MRI, including cerebral microbleeds, cortical superficial siderosis, white matter hyperintensity, MRI-visible perivascular spaces, and cortical microinfarcts. As imaging techniques advance, not only does the resolution of conventional imaging improve, but novel skills in functional and molecular imaging studies also enable in vivo analysis of vessel physiological changes and underlying pathology. These modern tools help in early detection of CAA and may potentially serve as sensitive outcome markers in future clinical trials. In this article, we reviewed past studies of CAA focusing on utilization of various conventional and novel imaging techniques in both research and clinical aspects.

Microangiopathy underlying mixed-location intracerebral hemorrhages/microbleeds: A PiB-PET study

OBJECTIVE

To test the hypothesis that patients with concomitant lobar and deep intracerebral hemorrhages/microbleeds (mixed ICH) have predominantly hypertensive small vessel disease (HTN-SVD) rather than cerebral amyloid angiopathy (CAA), using in vivo amyloid imaging.

METHODS

Eighty Asian patients with primary ICH without dementia were included in this cross-sectional study. All patients underwent brain MRI and 11C-Pittsburgh compound B (PiB)-PET imaging. The mean cortical standardized uptake value ratio (SUVR) was calculated using cerebellum as reference. Forty-six patients (57.5%) had mixed ICH. Their demographic and clinical profile as well as amyloid deposition patterns were compared to those of 13 patients with CAA-ICH and 21 patients with strictly deep microbleeds and ICH (HTN-ICH).

RESULTS

Patients with mixed ICH were younger (62.8 ± 11.7 vs 73.3 ± 11.9 years in CAA, p = 0.006) and showed a higher rate of hypertension than patients with CAA-ICH (p < 0.001). Patients with mixed ICH had lower PiB SUVR than patients with CAA (1.06 [1.01-1.13] vs 1.43 [1.06-1.58], p = 0.003). In a multivariable logistic regression model, mixed ICH was associated with hypertension (odds ratio 8.9, 95% confidence interval 1.4-58.4, p = 0.02) and lower PiB SUVR (odds ratio 0.03, 95% confidence interval 0.001-0.87, p = 0.04) compared to CAA after adjustment for age. Compared to HTN-ICH, mixed ICH showed a similar mean age (62.8 ± 11.7 vs 60.1 ± 14.5 years in HTN-ICH) and risk factor profile (all p > 0.1). Furthermore, PiB SUVR did not differ between mixed ICH (values presented above) and HTN-ICH (1.10 [1.00-1.16], p = 0.45).

CONCLUSIONS

Patients with mixed ICH have much lower amyloid load than patients with CAA-ICH, while being similar to HTN-ICH. Overall, mixed ICH is probably caused by HTN-SVD, an important finding with clinical relevance.

Predictors of new remote cerebral microbleeds after IV thrombolysis for ischemic stroke

OBJECTIVE

To assess the frequency, associated factors, and underlying vasculopathy of new remote cerebral microbleeds (CMB), as well as the risk of concomitant hemorrhagic complications related to new CMBs, after IV thrombolysis (IVT) in acute stroke patients.

METHODS

We conducted an observational study using data from our local thrombolysis registry. We included consecutive stroke patients with MRI (3T)-based IVT and a follow-up MRI the next day between 2008 and 2017 (n = 396). Only CMBs located outside of the ischemic lesions were considered. We also performed a meta-analysis on new CMBs after IVT that included 2 additional studies.

RESULTS

In our cohort, new remote CMBs occurred in 16/396 patients (4.0%) after IVT and the distribution was strictly lobar in 13/16 patients (81%). Patients with preexisting CMBs with a strictly lobar distribution were significantly more likely to have new CMBs after IVT (p = 0.014). In the random-effects meta-analysis (n = 741), the pooled cumulative frequency of new CMBs after IVT was 4.4%. A higher preexisting CMB burden (>2) was associated with a higher likelihood of new CMBs (odds ratio [OR] 3.6, 95% confidence interval [CI] 1.3-10.3) and new CMBs were associated with the occurrence of remote parenchymal hemorrhage (OR 28.8, 95% CI 8.6-96.4).

CONCLUSIONS

New remote CMBs after IVT occurred in 4% of stroke patients, mainly had a strictly lobar distribution, and were associated with IVT-related hemorrhagic complications. Preexisting CMBs with a strictly lobar distribution and a higher CMB burden were associated with new CMBs after IVT, which may indicate an underlying cerebral amyloid angiopathy.

Cerebral small vessel disease in patients with spontaneous cerebellar hemorrhage

BACKGROUND

Spontaneous cerebellar-intracerebral hemorrhage (ICH) can be associated with both cerebral amyloid angiopathy (CAA) and hypertensive small vessel disease (HTN-SVD, i.e. arteriolosclerosis). To better understand the underlying microangiopathy of cerebellar-ICH, we aimed to evaluate the spatial distribution of supratentorial cerebral microbleeds (CMBs) and neuropathologic profiles in these patients.

METHODS

We enrolled consecutive cerebellar-ICH patients. Clinical variables and MRI markers specific for CAA and HTN-SVD were assessed. Patients were classified into categories according to the topography (strictly-lobar, strictly-deep, and mixed) of supratentorial CMBs and comparisons were performed. Available neuropathological material was reviewed to evaluate the presence and severity of arteriolosclerosis and CAA.

RESULTS

Ninety-eight cerebellar-ICH patients were enrolled. Fifty patients (51%) had at least one supratentorial CMB. Twelve patients (12%) had strictly lobar-CMBs, 12 patients (12%) showed strictly deep-CMBs and mixed-CMBs (lobar and deep CMBs) were present in 26 cerebellar-ICH patients (27%). In multivariable analysis, cerebellar-ICH patients with mixed-CMBs were associated with higher prevalence of hypertension (OR 4.9, 95% confidence interval [CI] 1.2-20, p = 0.017) but with lower prevalence of severe centrum-semiovale enlarged perivascular spaces (OR 0.2, CI 0.05-0.8, p = 0.024) when compared to cerebellar-ICH patients with strictly lobar-CMBs. Vascular risk factors and neuroimaging characteristics were similar between strictly deep-CMBs and mixed-CMBs. Six patients had available neuropathological material for analyses and they all showed some degree of arteriolosclerosis.

CONCLUSIONS

Cerebellar-ICH patients frequently show supratentorial CMBs. The mixed-CMBs pattern appears to be the most common. Our radiological and pathological results suggest that the majority of cerebellar-ICH patients harbor HTN-SVD as dominant microangiopathy.

Characteristics of Cerebral Microbleeds

Cerebral microbleeds (CMBs) are increasingly recognized neuroimaging findings, occurring with cerebrovascular disease, dementia, and aging. CMBs are associated with subsequent hemorrhagic and ischemic stroke, and also with an increased risk of cognitive deterioration and dementia. They occur in the setting of impaired small vessel integrity due to hypertension or cerebral amyloid angiopathy. This review summarizes the concepts, cause or risk factors, histopathological mechanisms, and clinical consequences of CMBs.

The association between hypertensive arteriopathy and cerebral amyloid angiopathy in spontaneously hypertensive stroke-prone rats

We aimed to test the hypothesis that in spontaneously hypertensive stroke‐prone rats (SHRSP), non‐amyloid cerebral small vessel disease/hypertensive arteriopathy (HA) results in vessel wall injury that may promote cerebral amyloid angiopathy (CAA). Our study comprised 21 male SHRSP (age 17–44 weeks) and 10 age‐ and sex‐matched Wistar control rats, that underwent two‐photon (2PM) imaging of the arterioles in the parietal cortex using Methoxy‐X04, Dextran and cerebral blood flow (CBF) measurements. Our data suggest that HA in SHRSP progresses in a temporal and age‐dependent manner, starting from small vessel wall damage (stage 1A), proceeding to CBF reduction (stage 1B), non‐occlusive (stage 2), and finally, occlusive thrombi (stage 3). Wistar animals also demonstrated small vessel wall damage, but were free of any of the later HA stages. Nearly half of all SHRSP additionally displayed vascular Methoxy‐X04 positivity indicative of cortical CAA. Vascular β‐amyloid deposits were found in small vessels characterized by thrombotic occlusions (stage 2 or 3). Post‐mortem analysis of the rat brains confirmed the findings derived from intravital 2PM microscopy. Our data thus overall suggest that advanced HA may play a role in CAA development with the two small vessel disease entities might be related to the same pathological spectrum of the aging brain.

Cerebral small vessel disease burden and functional and radiographic outcomes in intracerebral hemorrhage

OBJECTIVE

To examine the effect of individual cerebral small vessel disease (CSVD) markers and cumulative CSVD burden on functional independence, ambulation and hematoma expansion in spontaneous intracerebral hemorrhage (ICH).

METHODS

Retrospective analysis of prospectively collected data from an observational study of consecutive patients with spontaneous ICH, brain MRI within 1 month from ictus, premorbid modified Rankin Scale (mRS) score ≤ 2, available imaging data and 90-day functional status in a tertiary academic center. Functional outcomes included 90-day functional independence (mRS ≤ 2) and independent ambulation; radiographic outcome was hematoma expansion (> 12.5 ml absolute or > 33% relative increase in ICH volume). We identified the presence and burden of individual CSVD markers (cerebral microbleeds (CMBs), enlarged perivascular spaces, lacunes, white matter hyperintensities) and composite CSVD burden score and explored their association with outcomes of interest in multivariable models adjusting for well-established confounders.

RESULTS

111 patients were included, 65% lobar ICH, with a median volume 20.8 ml. 43 (38.7%) achieved functional independence and 71 (64%) independent ambulation. In multivariable adjusted models, there was higher total CSVD burden (OR 0.61, 95% CI 0.37-0.96, p = 0.03) and CMBs presence (OR 0.32, 95% CI 0.1-0.88, p = 0.04) remained independently inversely associated with functional independence. Individual CSVD markers or total CSVD score had no significant relation with ambulation and ICH expansion. Larger ICH volume and deep ICH location were the major determinants of lack of independent ambulation.

CONCLUSIONS

Our findings suggest that in ICH patients without previous functional dependence, total CSVD burden and particularly presence of CMBs significantly affect functional recovery. The latter is a novel finding and merits further exploration.

Updates on Prevention of Hemorrhagic and Lacunar Strokes

Intracerebral hemorrhage (ICH) and lacunar infarction (LI) are the major acute clinical manifestations of cerebral small vessel diseases (cSVDs). Hypertensive small vessel disease, cerebral amyloid angiopathy, and hereditary causes, such as Cerebral Autosomal Dominant Arteriopathy with Subcortical Infarcts and Leukoencephalopathy (CADASIL), constitute the three common cSVD categories. Diagnosing the underlying vascular pathology in these patients is important because the risk and types of recurrent strokes show significant differences. Recent advances in our understanding of the cSVD-related radiological markers have improved our ability to stratify ICH risk in individual patients, which helps guide antithrombotic decisions. There are general good-practice measures for stroke prevention in patients with cSVD, such as optimal blood pressure and glycemic control, while individualized measures tailored for particular patients are often needed. Antithrombotic combinations and anticoagulants should be avoided in cSVD treatment, as they increase the risk of potentially fatal ICH without necessarily lowering LI risk in these patients. Even when indicated for a concurrent pathology, such as nonvalvular atrial fibrillation, nonpharmacological approaches should be considered in the presence of cSVD. More data are emerging regarding the presentation, clinical course, and diagnostic markers of hereditary cSVD, allowing accurate diagnosis, and therefore, guiding management of symptomatic patients. When suspicion for asymptomatic hereditary cSVD exists, the pros and cons of prescribing genetic testing should be discussed in detail in the absence of any curative treatment. Recent data regarding diagnosis, risk stratification, and specific preventive approaches for both sporadic and hereditary cSVDs are discussed in this review article.

Association of Chronic Kidney Disease With Small Vessel Disease in Patients With Hypertensive Intracerebral Hemorrhage

Background

Chronic kidney disease (CKD) has been closely associated with hypertension and stroke. Although studies have reported the relationship between CKD and cerebral small vessel disease (SVD), the link between CKD, hypertension, and SVD is uncertain. The aim of this study was to investigate the association between CKD and SVD in patients with strictly hypertensive intracerebral hemorrhage (ICH).

Methods

142 patients with acute hypertensive ICH were enrolled in this study. Magnetic resonance imaging was performed to assess imaging markers for SVD. Patients were categorized into three CKD groups based on the degree of kidney dysfunction [glomerular filtration rate (GFR) in milliliters per minute per 1.73 m²]: normal kidney function (GFR ≥ 90), mild kidney disease (60 ≤ GFR < 90), and moderate to severe kidney disease (GFR < 60).

Results

The prevalence rate of mild and moderate to severe CKD was 50 and 14.8%, respectively. The stage of CKD was associated with history of chronic hypertension (p = 0.046) as well as the prevalence rate of overall and deep cerebral microbleed (CMB) (p = 0.001 and p = 0.002, respectively). The stage of CKD was a significant risk factor for deep white matter hyperintensity (WMH) (OR 1.848; 95% CI 1.022–3.343, p = 0.042), overall CMB (OR 2.628; 95% CI 1.462–4.724, p = 0.001), lobar CMB (OR 2.106; 95% CI 1.119–3.963, p = 0.021), and deep CMB (OR 2.237; 95% CI 1.263–3.960, p = 0.006), even after adjustment for confounders.

Conclusion

In patients with hypertensive ICH, the prevalence of CKD is high even at the early stage of renal function impairment and is associated with the prevalence of CMB and deep WMH. These results reinforce the notion of a link between hypertensive vasculopathy, renal function impairment, and cerebral SVD.

Distribution of Lacunar Infarcts in Asians With Intracerebral Hemorrhage: A Magnetic Resonance Imaging and Amyloid Positron Emission Tomography Study

BACKGROUND AND PURPOSE

We evaluated whether lacunes in centrum semiovale (lobar lacunes) were associated with cerebral amyloid angiopathy (CAA) markers in an Asian intracerebral hemorrhage (ICH) population.

METHODS

One hundred ten patients with primary ICH were classified as CAA-ICH (n=24; mean age, 70.9±13.9) or hypertensive ICH (n=86; mean age, 59.3±13.0) according to the presence of strictly lobar (per modified Boston criteria) or strictly deep bleeds (both ICH and cerebral microbleeds), respectively. Lacunes were evaluated in the supratentorial area and classified as lobar or classical deep based on the location. A subgroup of 36 patients also underwent Pittsburgh Compound B positron emission tomography to measure cerebral amyloid deposition and global standardized uptake value ratio were calculated.

RESULTS

Lobar lacunes were more frequent in CAA-ICH than hypertensive ICH (29.2 versus 11.6%; P=0.036). In multivariable models, lobar lacunes were associated with lobar cerebral microbleed (odds ratio, 6.8; 95% confidence interval, 1.6-29.9; P=0.011) after adjustment for age, sex, hypertension, and white matter hyperintensity. In 15 CAA-ICH and 21 hypertensive ICH patients with Pittsburgh Compound B positron emission tomography, correlation analyses between lobar lacune counts and global standardized uptake value ratio showed positive association (ρ=0.40; P=0.02) and remained significant after adjustment for age (r=0.34; P=0.04).

CONCLUSIONS

Our findings expand on recent work showing that lobar lacunes are more frequent in CAA-ICH than hypertensive ICH. Their independent association with lobar cerebral microbleeds and brain amyloid deposition suggests a relationship with CAA even in an Asian cohort with overall higher hypertensive load.

Atrial Fibrillation for the Neurologist: Preventing both Ischemic and Hemorrhagic Strokes

PURPOSE OF REVIEW

This review aims to help neurologists managing atrial fibrillation (AF) patients who had an ischemic stroke and/or with intracranial hemorrhage (ICH) markers, therefore at high embolic/hemorrhagic risks.

RECENT FINDINGS

Implantable loop recorders have substantially improved the accuracy of AF detection. Recent research yielded a set of powerful neuroimaging markers that can stratify ICH risk. Direct oral anticoagulants (DOAC) are easier to use with a lower ICH risk than warfarin in a general AF population. Finally, the FDA-approved left atrial appendage closure (LAAC) with the WATCHMAN device provides an option without the need for life-long anticoagulation. In this review, we introduce the concept of preventing both ischemic and hemorrhagic strokes in AF patients through accurate AF diagnosis and stratification of both embolic and ICH risks. LAAC can be considered in patients at higher hemorrhagic risks while warfarin/DOAC use should be individualized in the majority of AF patients at a low risk of bleeding.