Cortical superficial siderosis: A prospective observational cohort study

Clinical and Neuroradiological Manifestations of Cerebral Amyloid Angiopathy: A Closer Look into the Natural History of a Frequent Disease

Cerebral amyloid angiopathy (CAA) is one of the most prevalent small vessel diseases (SVDs). Its neuroradiological hallmarks are both hemorrhagic and non-hemorrhagic ones. Among the clinical manifestations, transient focal neurological episodes (TFNEs) are associated with an increased risk of bleeding in a short time period and with convexal subarachnoid hemorrhage (SAH). The natural history of CAA is incompletely characterized in the literature, because the focus has been mostly on hemorrhagic events, while both clinical and non-hemorrhagic presentations are possible and sometimes underestimated. Furthermore, new diagnostic criteria have incorporated non-hemorrhagic Magnetic Resonance Imaging (MRI) markers and non-hemorrhagic clinical presentations. Disease trajectories are often individual and help provide food for thought and discussion on some issues, thus allowing for a greater and deeper evaluation. We, therefore, present a case that exemplifies how the natural history of CAA can be atypical compared to its expected course, which is long and not only hemorrhagic. Several episodes of CAA-related inflammation, with prevalent, but not exclusive, leptomeningeal involvement, were evaluated and treated in the presented case, in which the intraparenchymal cerebral hemorrhagic manifestation was the last in the patient's history. CAA may have a very long natural history. During the disease's course, inflammatory features might be prominent in neuroimaging but not strongly symptomatic, and intraparenchymal cerebral hemorrhage (ICH) may be a late event. The awareness of this subtype of the disease allows us to better explore the pathophysiology of CAA and to increase the level of clinical suspicion for the diagnosis. Furthermore, the distinction between different disease phenotypes can provide useful information for patient management in clinical practice.

Combined effect of cortical superficial siderosis and cerebral microbleed on short-term and long-term outcomes after intracerebral haemorrhage

BACKGROUND AND PURPOSE

Cortical superficial siderosis (cSS) and cerebral microbleed (CMB) have distinct effects on intracerebral haemorrhage (ICH). We aim to investigate the combined effect of cSS and CMB on outcomes after ICH.

METHODS

Based on a single-centre stroke registry database, patients with spontaneous ICH who had CT scan within 48 hours after ictus and MRI subsequently were identified. Eligible patients were divided into four groups (cSS-CMB-, cSS-CMB+, cSS+CMB-, cSS+CMB+) according to cSS and CMB on susceptibility-weighted image of MRI. Primary outcomes were haematoma volume on admission and unfavourable outcome defined as modified Rankin Scale scores ≥3 at 3 months. Secondary outcomes were all-cause death, recurrence of stroke and ICH during follow-up (median follow-up 2.0 years, IQR 1.0-3.0 years).

RESULTS

A total of 673 patients were identified from 1044 patients with spontaneous ICH. 131 (19.5%) had cSS and 468 (69.5%) had CMB. Patients with cSS+CMB+ had the highest rate of poor outcome at 3 months, as well as all-cause death, recurrent stroke and ICH during follow-up. In cSS- patients, CMB was associated with smaller haematoma (β -0.13; 95% CI -0.22 to -0.03; p=0.009), but it still increased risks of recurrent ICH (OR 4.6; 95% CI 1.3 to 15.6; p=0.015) and stroke (OR 2.0; 95% CI 1.0 to 4.0; p=0.049). These effects of CMB became unremarkable in the context of cSS+.

CONCLUSIONS

Patients with different combinations of cSS and CMB have distinct patterns of short-term and long-term outcomes. Although CMB is related to restrained haematoma, it does not improve long-term outcomes.

TRIAL REGISTRATION NUMBER

NCT04803292.

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.

Subarachnoid extension and unfavorable outcomes in patients with supratentorial intracerebral hemorrhage

OBJECTIVE

Our study aimed to investigate the association between the subarachnoid extension of intracranial hemorrhage (SAHE) and clinical outcomes in patients with supratentorial intracerebral hemorrhage (ICH).

METHODS

We analyzed the data from a prospective, multi-center, and registry-based database. Two experienced investigators independently assessed ICH imaging data. We compared baseline characteristics and follow-up outcomes. Multivariable logistic regression analysis was used to evaluate the association between SAHE and poor clinical outcomes. We also performed Kaplan-Meier curves and Cox proportional hazards regression analyses to analyze whether SAHE was relevant to a higher mortality rate.

RESULTS

A total of 931 patients were included in this study (SAHE vs. no SAHE, 121 [13.0%] vs. 810 [87.0%]). Patients with SAHE had more severe neurological deficits, higher scores of the mRS, and more remarkable mortality rates at follow-up (all p values < 0.05). In multivariable-adjusted models, SAHE was independently associated with a higher risk of poor outcomes (adjusted OR [95%CI]: 2.030 [1.142-3.608] at 3 months; 2.348 [1.337-4.123] at 1 year). In addition, SAHE remained an independent association with an increased death rate at 1 year (adjusted HR [95%CI], 1.314[1.057-1.635]). In the subgroup analysis, the correlation between SAHE and prognosis exists in patients with lobar or deep ICH.

CONCLUSIONS

SAHE is independently associated with poor outcomes in patients with supratentorial ICH. It may provide a promising target for developing new predictive tools targeting ICH.

Cortical superficial siderosis, hematoma volume, and outcomes after intracerebral hemorrhage: a mediation analysis

Background

Previous studies have shown that cortical superficial siderosis (cSS) can increase hematoma volume and predict poor outcomes following primary intracerebral hemorrhage (ICH).

Objective

We aimed to determine whether a large hematoma volume was the essential factor contributing to worse outcomes of cSS.

Methods

Patients with spontaneous ICH underwent a CT scan within 48 h after ictus. Evaluation of cSS was performed using magnetic resonance imaging (MRI) within 7 days. The 90-day outcome was assessed using the modified Rankin Scale (mRS). In addition, we investigated the correlation between cSS, hematoma volume, and 90-day outcomes using multivariate regression and mediation analyses.

Results

Among the 673 patients with ICH [mean (SD) age, 61 (13) years; 237 female subjects (35.2%); median (IQR) hematoma volume, 9.0 (3.0-17.6) ml], 131 (19.5%) had cSS. There was an association between cSS and larger hematoma volume (β = 4.449, 95% CI 1.890-7.009, p < 0.001) independent of hematoma location and was also related to worse 90-day mRS (β = 0.333, 95% CI 0.008-0.659, p = 0.045) in multivariable regression. In addition, mediation analyses revealed that hematoma volume was an essential factor mediating the effect of cSS on unfavorable 90-day outcomes (proportion mediated:66.04%, p = 0.01).

Conclusion

Large hematoma volume was the major charge of directing cSS to worse outcomes in patients with mild to moderate ICH, and cSS was related to a larger hematoma in both lobar and non-lobar areas.

Clinical trial registration

https://clinicaltrials.gov/ct2/show/NCT04803292, identifier: NCT04803292.

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.

Prevalence of Clinical and Neuroimaging Markers in Cerebral Amyloid Angiopathy: A Systematic Review and Meta-Analysis

BACKGROUND

Limited data exist regarding the prevalence of clinical and neuroimaging manifestations among patients diagnosed with cerebral amyloid angiopathy (CAA). We sought to determine the prevalence of clinical phenotypes and radiological markers in patients with CAA.

METHODS

Systematic review and meta-analysis of studies including patients with CAA was conducted to primarily assess the prevalence of clinical phenotypes and neuroimaging markers as available in the included studies. Sensitivity analyses were performed based on the (1) retrospective or prospective study design and (2) probable or unspecified CAA status. We pooled the prevalence rates using random-effects models and assessed the heterogeneity using the Cochran Q and I² statistics.

RESULTS

We identified 12 prospective and 34 retrospective studies including 7159 patients with CAA. The pooled prevalence rates were cerebral microbleeds (52% [95% CI, 43%-60%]; I²=93%), cortical superficial siderosis (49% [95% CI, 38%-59%]; I²=95%), dementia or mild cognitive impairment (50% [95% CI, 35%-65%]; I²=97%), intracerebral hemorrhage (ICH; 44% [95% CI, 27%-61%]; I²=98%), transient focal neurological episodes (48%; 10 studies [95% CI, 29%-67%]; I²=97%), lacunar infarcts (30% [95% CI, 25%-36%]; I²=78%), high grades of perivascular spaces located in centrum semiovale (56% [95% CI, 44%-67%]; I²=88%) and basal ganglia (21% [95% CI, 2%-51%]; I²=98%), and white matter hyperintensities with moderate or severe Fazekas score (53% [95% CI, 40%-65%]; I²=91%). The only neuroimaging marker that was associated with higher odds of recurrent ICH was cortical superficial siderosis (odds ratio, 1.57 [95% CI, 1.01-2.46]; I²=47%). Sensitivity analyses demonstrated a higher prevalence of ICH (53% versus 16%; P=0.03) and transient focal neurological episodes (57% versus 17%; P=0.03) among retrospective studies compared with prospective studies. No difference was documented between the prevalence rates based on the CAA status.

CONCLUSIONS

Approximately one-half of hospital-based cohort of CAA patients was observed to have cerebral microbleeds, cortical superficial siderosis, mild cognitive impairment, dementia, ICH, or transient focal neurological episodes. Cortical superficial siderosis was the only neuroimaging marker that was associated with higher odds of ICH recurrence. Future population-based studies among well-defined CAA cohorts are warranted to corroborate our findings.

Long-term functional decline of spontaneous intracerebral haemorrhage survivors

OBJECTIVE

To identify in patients who survived 6 months after a spontaneous intracerebral haemorrhage (ICH) baseline characteristics and new clinical events associated with functional decline.

METHODS

In a single-centre study, we prospectively included 6-month survivors with a modified Rankin Scale (mRS) score 0-3. We defined functional decline by a transition to mRS 4-5. We evaluated associations of baseline characteristics and new clinical events with functional decline, using univariate and multivariable models.

RESULTS

Of 560 patients, 174 (31%) had an mRS score 0-3 at 6 months. During a median follow-up of 9 years (IQR 8.1-9.5), 40 (23%) converted to mRS 4-5. Age, diabetes mellitus, ICH volume and higher mRS scores at 6 months were independently associated with functional decline. Among baseline MRI markers, presence of strictly lobar cerebral microbleeds (CMBs), and mixed lobar and deep CMBs were independently associated with functional decline. When new clinical events occurring during follow-up were added in multivariable models, age (cause-specific HR (CSHR): 1.07; 95% CI: 1.03 to 1.11), ICH volume (CSHR: 1.03; 95% CI: 1.01 to 1.06), mRS score at 6 months (CSHR per 1 point increase 1.61, 95% CI 1.07 to 2.43), occurrence of dementia (CSHR: 3.81, 95% CI: 1.78 to 8.16) and occurrence of any stroke (CSHR: 4.29, 95% CI: 1.80 to 10.22) remained independently associated with transition to mRS 4-5.

INTERPRETATION

Almost one-fourth of patients with spontaneous ICH developed a functional decline over time. Age, ICH volume, higher mRS score at 6 months and new clinical events after ICH are the major determinants.

MRI phenotyping of underlying cerebral small vessel disease in mixed hemorrhage patients

OBJECTIVE

To investigate underlying cerebral small vessel disease (CSVD) in patients with mixed cerebral hemorrhages patterns and phenotype them according to the contribution of the two most common sporadic CSVD subtypes: cerebral amyloid angiopathy (CAA) vs. hypertensive arteriopathy (HA).

METHODS

Brain MRIs of patients with intracerebral hemorrhages (ICHs) and/or cerebral microbleeds (CMBs) were assessed for the full spectrum of CSVD markers using validated scales: ICHs, CMBs, cortical superficial siderosis (cSS), white matter hyperintensities, MRI-visible perivascular spaces (PVS). PVS predominance pattern was grouped as centrum-semiovale (CSO)-PVS predominance, basal-ganglia (BG)-PVS predominance, CSO-PVS and BG-PVS equality. Patients with mixed cerebral hemorrhages were classified into mixed CAA-pattern or mixed HA-pattern according to the existence of cSS and/or a CSO-PVS predominance pattern and comparisons were performed.

RESULTS

We included 110 patients with CAA (strictly lobar ICHs/CMBs), 33 with HA (strictly deep ICHs/CMBs) and 97 with mixed lobar/deep ICHs/CMBs. Mixed patients were more similar to HA with respect to their MRI-CSVD markers, vascular risk profile and cerebrospinal fluid (CSF) measures. In the mixed patients, 33 (34%) had cSS, a CSO-PVS predominance pattern, or both, and were defined as mixed CAA-pattern cases. The mixed CAA-pattern patients were more alike CAA patients regarding their MRI-CSVD markers, CSF and genetic profile.

CONCLUSION

Our findings suggest that the heterogeneous group of patients with mixed cerebral hemorrhages distribution can be further phenotyped according to the predominant underlying CSVD. cSS presence and a CSO-PVS predominance pattern could serve as strongly suggestive markers of a contribution from CAA among patients with mixed hemorrhages.

CT-Visible Convexity Subarachnoid Hemorrhage is Associated With Cortical Superficial Siderosis and Predicts Recurrent ICH

OBJECTIVE

To investigate whether acute convexity subarachnoid hemorrhage (cSAH) detected on CT in lobar intracerebral hemorrhage (ICH) related to cerebral amyloid angiopathy (CAA) is associated with recurrent ICH.

METHODS

We analyzed data from a prospective cohort of consecutive acute lobar ICH survivors fulfilling the Boston criteria for possible or probable CAA who had both brain CT and MRI at index ICH. Presence of cSAH was assessed on CT blinded to MRI data. Cortical superficial siderosis (cSS), cerebral microbleeds, and white matter hyperintensities were evaluated on MRI. Cox proportional hazard models were used to assess the association between cSAH and the risk of recurrent symptomatic ICH during follow-up.

RESULTS

A total of 244 ICH survivors (76.4 ± 8.7 years; 54.5% female) were included. cSAH was observed on baseline CT in 99 patients (40.5%). Presence of cSAH was independently associated with cSS, hematoma volume, and preexisting dementia. During a median follow-up of 2.66 years, 49 patients (20.0%) had recurrent symptomatic ICH. Presence of cSAH was associated with recurrent ICH (hazard ratio 2.64; 95% confidence interval 1.46-4.79; p = 0.001), after adjusting for age, antiplatelet use, warfarin use, and history of previous ICH.

CONCLUSION

cSAH was detected on CT in 40.5% of patients with acute lobar ICH related to CAA and heralds an increased risk of recurrent ICH. This CT marker may be widely used to stratify the ICH risk in patients with CAA.

CLASSIFICATION OF EVIDENCE

This study provides Class II evidence that cSAH accurately predicts recurrent stroke in patients with CAA.

Superficial Siderosis and Microbleed Restricted in Cortex Might Be Correlated to Atrophy and Cognitive Decline in Sneddon's Syndrome

Objective: Sneddon's syndrome is a rare non-inflammatory arteriopathy affecting small and medium-sized arteries, characterized by a generalized livedo reticularis and recurrent transient ischemic attack or ischemic stroke. Hemorrhagic stroke was reported in limited cases, but microbleeds and superficial siderosis were rarely issued. We aimed to investigate the hemorrhagic imaging features of Sneddon's syndrome and explore the possible mechanism and clinical relevance. Methods: Clinical data and cerebral MR imaging including T2* sequence of seven consecutive patients with Sneddon's syndrome were reviewed. Results: The most common neurological manifestations were cognitive impairment and stroke attack (71.4%), followed by seizures and movement disorder (28.6%). Cerebral microbleeds were detected in six patients on T2* sequence, all of them presented with cortical microbleeds, only one of them with microbleeds in basal ganglion. More than five microbleeds were observed in four of these six patients. The majority of the microbleeds were predominantly cortical restricted and especially located in the cortical watersheds. Multiple superficial siderosis were identified mainly involving cortical watersheds in five cases. Significant cerebral atrophy with prominent secondary white matter hyperintensities in bilateral cortical watersheds were also observed. Abnormal tortuous and multiple focal occlusion of bilateral distal MCA were shown in one patient by DSA. No stenosis of proximal segment of cerebral arteries was detected in all the patients. Conclusions: This is the first report illustrating abundant cortical microbleeds and superficial siderosis mainly involved the anterior and posterior cortical watersheds in Sneddon's syndrome. The surprisingly identical topographic distribution of hemorrhagic lesions and the obvious atrophy suggest cerebral atrophy might be secondary to the microangiopathy related hemorrhagic lesions and further contribute to the neurological deficit, especially the early cognitive decline in Sneddon syndrome.

Long-term mortality in survivors of spontaneous intracerebral hemorrhage

Background

Factors associated with long-term mortality after spontaneous intracerebral hemorrhage (ICH) have been poorly investigated.

Aim

Our objective was to identify variables associated with long-term mortality in a prospective cohort of 30-day ICH survivors.

Methods

We prospectively included consecutive 30-day spontaneous ICH survivors. We evaluated baseline and follow-up clinical characteristics and magnetic resonance imaging (MRI) markers of chronic brain injury as variables associated with long-term mortality using univariate and multivariable Cox proportional hazard regression models.

Results

Of 560 patients with spontaneous ICH, 304 (54.2%) survived more than 30 days and consented for follow-up. During a median follow-up of 10 years (interquartile range: 8.0–10.5), 176 patients died. The cumulative survival rate at 10 years was 38%. In multivariable analysis, variables independently associated with long-term mortality were age (hazard ratio (HR) per 10-year increase: 1.68, 95% confidence interval (CI): 1.45–1.95), male gender (HR: 1.41, CI: 1.02–1.95), prestroke dependency (HR: 1.66, CI: 1.15–2.39), National Institutes of Health Stroke Scale score (HR per 1-point increase: 1.03, CI: 1.01–1.04), occurrence of any stroke (HR: 2.24, CI: 1.39–3.60), and dementia (HR: 1.51, CI: 1.06–2.16) during follow-up. Among MRI markers, only cerebral atrophy (HR per 1-point increase: 1.50, CI: 1.13–2.00) was independently associated with long-term mortality.

Conclusions

Preexisting comorbidities, clinical severity at presentation, and significant clinical event during follow-up are associated with long-term mortality. Among MRI markers of chronic brain injury, only cerebral atrophy is associated with long-term mortality.

Cortical superficial siderosis progression in cerebral amyloid angiopathy: Prospective MRI study

OBJECTIVE

To investigate the prevalence, predictors, and clinical relevance of cortical superficial siderosis (cSS) progression in cerebral amyloid angiopathy (CAA).

METHODS

Consecutive patients with symptomatic CAA meeting Boston criteria in a prospective cohort underwent baseline and follow-up MRI within 1 year. cSS progression was evaluated on an ordinal scale and categorized into mild (score 1-2 = cSS extension within an already present cSS focus or appearance of 1 new cSS focus) and severe progression (score 3-4 = appearance of ≥2 new cSS foci). Binominal and ordinal multivariable logistic regression were used to determine cSS progression predictors. We investigated future lobar intracerebral hemorrhage (ICH) risk in survival analysis models.

RESULTS

We included 79 patients with CAA (mean age, 69.2 years), 56 (71%) with lobar ICH at baseline. cSS progression was detected in 23 (29%) patients: 15 (19%) patients had mild and 8 (10%) severe progression. In binominal multivariable logistic regression, ICH presence (odds ratio [OR], 7.54; 95% confidence interval [CI], 1.75-53.52; p = 0.016) and baseline cSS (OR, 10.41; 95% CI, 2.84-52.83; p = 0.001) were independent predictors of cSS progression. In similar models, presence of disseminated (but not focal) cSS at baseline (OR, 5.58; 95% CI, 1.81-19.41; p = 0.004) was an independent predictor of cSS progression. Results were similar in ordinal multivariable logistic regression models. In multivariable Cox regression analysis, severe cSS progression was independently associated with increased future ICH risk (HR, 5.90; 95% CI, 1.30-26.68; p = 0.021).

CONCLUSIONS

cSS evolution on MRI is common in patients with symptomatic CAA and might be a potential biomarker for assessing disease severity and future ICH risk. External validation of these findings is warranted.

Convexity subarachnoid hemorrhage in lobar intracerebral hemorrhage: A prognostic marker

OBJECTIVE

To investigate whether acute convexity subarachnoid hemorrhage (cSAH) associated with acute lobar intracerebral hemorrhage (ICH) increases the risk of ICH recurrence in patients with cerebral amyloid angiopathy (CAA).

METHODS

We analyzed data from a prospective cohort of consecutive survivors of acute spontaneous lobar ICH fulfilling the Boston criteria for possible or probable CAA (CAA-ICH). We analyzed baseline clinical and MRI data, including cSAH (categorized as adjacent or remote from ICH on a standardized scale), cortical superficial siderosis (cSS), and other CAA MRI markers. Multivariable Cox regression models were used to assess the association between cSAH and recurrent symptomatic ICH during follow-up.

RESULTS

We included 261 CAA-ICH survivors (mean age 76.2 ± 8.7 years). Of them, 166 (63.6%, 95% confidence interval [CI] 57.7%-69.5%) had cSAH on baseline MRI. During a median follow-up of 28.3 (interquartile range 7.2-57.0) months, 54 (20.7%) patients experienced a recurrent lobar ICH. In Cox regression, any cSAH, adjacent cSAH, and remote cSAH were independent predictors of recurrent ICH after adjustment for other confounders, including cSS. Incidence rate of recurrent ICH in patients with cSAH was 9.9 per 100 person-years (95% CI 7.3-13.0) compared with 1.2 per 100 person-years (95% CI 0.3-3.2) in those without cSAH (adjusted hazard ratio 7.5, 95% CI 2.6-21.1).

CONCLUSION

In patients with CAA-related acute ICH, cSAH (adjacent or remote from lobar ICH) is commonly observed and heralds an increased risk of recurrent ICH. cSAH may help stratify bleeding risk and should be assessed along with cSS for prognosis and clinical management.

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

OBJECTIVE

To assess the association of cortical superficial siderosis (cSS) presence and extent with future bleeding risk in cerebral amyloid angiopathy (CAA).

METHODS

This was a meta-analysis of clinical cohorts of symptomatic patients with CAA who had T2*-MRI at baseline and clinical follow-up for future intracerebral hemorrhage (ICH). We pooled data in a 2-stage meta-analysis using random effects models. Covariate-adjusted hazard ratios (adjHR) from multivariable Cox proportional hazard models were used.

RESULTS

We included data from 6 eligible studies (n = 1,239). cSS pooled prevalence was 34% (95% confidence interval [CI] 26%-41%; I ² 87.94%; p < 0.001): focal cSS prevalence was 14% (95% CI 12%-16%; I ² 6.75%; p = 0.37), and disseminated cSS prevalence was 20% (95% CI 13%-26%; I ² 90.39%; p < 0.001). During a mean follow-up of 3.1 years (range 1-4 years), 162/1,239 patients experienced a symptomatic ICH-pooled incidence rate 6.9% per year (95% CI 3.9%-9.8% per year; I ² 83%; p < 0.001). ICH incidence rates per year according to cSS status were 3.9% (95% CI 1.7%-6.1%; I ² 70%; p = 0.018) for patients without cSS, 11.1% (95% CI 7%-15.2%; I ² 56.8%; p = 0.074) for cSS presence, 9.1% (95% CI 5.5%-12.8%; I ² 0%; p = 0.994) for focal cSS, and 12.5% (95% CI 5.3%-19.7%; I ² 73.2%; p = 0.011) for disseminated cSS. In adjusted pooled analysis, any cSS presence was independently associated with increased future ICH risk (adjHR 2.14; 95% CI 1.19-3.85; p < 0.0001). Focal cSS was linked with ICH risk (adjHR 2.11; 95% CI 1.31-2.41; p = 0.002), while disseminated cSS conferred the strongest bleeding risk (adjHR 4.28; 95% CI 2.91-6.30; p < 0.0001).

CONCLUSION

In patients with CAA, cSS presence and extent are the most important MRI prognostic risk factors for future ICH, likely useful in treatment planning.

CLASSIFICATION OF EVIDENCE

This study provides Class III evidence that in symptomatic CAA survivors with baseline T2*-MRI, cSS (particularly if disseminated, i.e., affecting >3 sulci) increases the risk of future ICH.

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.

Association Between Cortical Superficial Siderosis and Dementia in Patients With Cognitive Impairment: A Meta-Analysis

Background: It remains unclear whether cortical superficial siderosis (cSS) is associated with dementia and its subtypes. We thus performed a meta-analysis to evaluate the relationship between dementia and cSS.

Methods: We searched EMBASE, PubMed, and Web of Science for relevant studies assessing risk of dementia and prevalence of cSS in patients with cognitive impairment. Fixed-effects and random-effects models were performed.

Results: Seven eligible studies including 3,218 patients with definite cognitive impairment were pooled in meta-analysis. The prevalence of cSS was 3.4%. The pooled analysis demonstrates odds ratio for cSS and dementia to be 1.60 (95% CI 1.04–2.44; p = 0.031). Subgroup analysis further indicated a significant association between cSS and Alzheimer's disease (AD) (OR = 2.01, 95% CI 1.34–3.02; p < 0.001), but not non-AD dementia (OR = 0.700, 95% CI 0.435–1.128; p = 0.143).

Conclusions: Our meta-analysis of available published data demonstrates an increased prevalence of dementia in the subjects with pre-existing cSS, especially for AD. These findings suggest cSS to be a candidate imaging indicator for AD. Further longitudinal research is needed to investigate the clinical relevance.

Prognostic relevance of cortical superficial siderosis in cerebral amyloid angiopathy

OBJECTIVE

To investigate the prognostic relevance of cortical superficial siderosis (cSS) in patients with cerebral amyloid angiopathy (CAA).

METHODS

A total of 302 patients fulfilling clinical and imaging criteria for probable or possible CAA were enrolled into a prospective, multicenter cohort study and followed for 12 months. cSS was assessed on T2*/susceptibility-weighted imaging MRI. The predefined primary composite endpoint was incident stroke or death in patients with cSS compared to those without. Secondary analyses included cerebrovascular events and functional outcome measured by the modified Rankin Scale (mRS). Multiple regression analysis was performed to adjust for possible confounders.

RESULTS

cSS prevalence was 40%. The primary endpoint occurred more frequently in patients with cSS (22%, 27/121) compared to those without (8%, 15/181, p = 0.001). Rates of CAA-related incident intracranial hemorrhage were 17% (cSS) and 4% (no cSS, p = 0.0003). The proportion of patients being functionally independent (mRS 0-2) 12 months from baseline were 59% (cSS) and 82% (no cSS, p = 0.00002). Presence of cSS was associated with the primary endpoint (adjusted odds ratio [OR] 1.2, 95% confidence interval [CI] 1.1-1.3, p = 0.0005), incident intracranial hemorrhage (adjusted OR 1.2, 95% CI 1.1-1.3, p = 0.0003), and less favorable outcome as assessed by the mRS (common OR 1.9, 95% CI 1.2-3.1, p = 0.009). Similar results were obtained in analyses restricted to patients with probable CAA and to patients with disseminated cSS (all p < 0.005).

CONCLUSIONS

Patients with cSS and suspected CAA are at high risk for CAA-related incident intracranial hemorrhage and poor functional outcome. Both the presence and extent of cSS have prognostic relevance and may influence clinical decision-making.