Superficial Siderosis Research Articles

The Predictive Values of Different Small Vessel Disease Scores on Clinical Outcomes in Mild ICH Patients.

Aim: To explore the predictive values of different small vessel disease (SVD) scores on functional recoveries and the clinical cerebrovascular events in mild intracerebral hemorrhage (ICH). Methods: In this study, we enrolled conscious and mild ICH patients without surgery and further divided them into the cerebral amyloid angiopathy (CAA)-ICH group and hypertension (HTN)-ICH group. The severity of individual SVD markers, including lacunes, cerebral microbleeds (CMBs), enlarged perivascular spaces (EPVS), white matter hyperintensity (WMH), and cortical superficial siderosis (cSS), was evaluated. The original SVD score, modified SVD score, refined SVD score, and CAA-SVD score and the total number of SVD markers were further calculated. Functional recoveries were evaluated using the modified Rankin scale. Recurrences of stroke were defined as readmission to the hospital with a definite diagnosis of stroke. Results: A total of 163 ICH patients (60 CAA-ICH and 103 HTN-ICH) were included in the study. The CAA-SVD score (OR=3.429; 95% confidence interval (CI)=1.518–7.748) had the best predictive effect on functional dependence in the CAA-ICH group, among which cSS severities probably played a vital role (OR=4.665; 95% CI=1.388–15.679). The total number of SVD markers [hazard ratio (HR)=3.765; 95% CI=1.467–9.663] can better identify stroke recurrences in CAA-ICH. In HTN-ICH, while the total number of SVD markers (HR=2.136; 95% CI=1.218–3.745) also demonstrated association with recurrent stroke, this effect seems to be related with the influence of lacunes (HR=5.064; 95% CI=1.697–15.116). Conclusions: The CAA-SVD score and the total number of SVD markers might identify mild CAA-ICH patients with poor prognosis. However, it would be better to focus on lacunes rather than on the overall burden of SVD to predict recurrent strokes in HTN-ICH.

Early MRI imaging and follow-up study in cerebral amyloid angiopathy.

AimTo study the imaging features of leukoaraiosis (LA) and hemorrhage in cerebral amyloid angiopathy (CAA) patients.MethodsThe earliest MRI images of probable CAA patients and non-CAA patients were collected. The characteristics of LA in the two groups were analyzed. Cerebral micro bleeding (CMB), superficial siderosis (SS), and intracranial hemorrhage (ICH) were recorded in the follow-up study. The space relationship between CMB or SS and ICH was assessed.ResultsWe found that 10/21 (47.6%) patients had occipital prominent LA and 14/21 (66.7%) patients had subcortical punctate LA before the ICH, which was higher than that of the ones in the control group (p = 0.015 and 0.038, respectively). The recurrence rate of ICH was 100% (3/3) in patients with diffuse SS and 36.4% (4/11) in patients without. The recurrence rate of ICH was 60% (3/5) in patients with multiple-lobe CMBs and 44.4% (4/9) in those without. The location of the ICH and CMB was inconsistent. ICH occurred in the ipsilateral cerebral hemisphere of SS in three patients with diffuse SS.ConclusionLA, diffuse SS, and multiple-lobe CMBs are important imaging characteristics of CAA, which may help make early diagnosis and predict the recurrence of ICH.

Intracerebral Hemorrhage Recurrence in Patients with and without Cerebral Amyloid Angiopathy

Background: Intracerebral hemorrhage (ICH) recurrence risk is known to be higher in patients with cerebral amyloid angiopathy (CAA) as compared to other causes of ICH. Risk factors for ICH recurrence are not completely understood, and our goal was to study specific imaging microangiopathy markers. Methods: Retrospective case-control study of patients with non-traumatic ICH admitted to a single center between 2014 and 2017 who underwent magnetic resonance imaging (MRI). Clinical characteristics of the index event and occurrence of death and ICH recurrence were collected from clinical records. MRI images were independently reviewed by 2 neuroradiologists. Groups of patients with CAA-related and CAA-unrelated ICH defined were compared. Presence of CAA was defined according to the Boston modified criteria. Survival analysis with Kaplan-Meier curves and Cox-regression analyses was performed to analyze ICH recurrence-free survival. Results: Among 448 consecutive patients with non-traumatic ICH admitted during the study period, 104 were included in the study, mean age 64 years (±13.5), median follow-up of 27 months (interquartile range, IQR 16–43), corresponding to 272 person-years of total follow-up. CAA-related ICH patients presented higher burden of lobar microbleeds (p < 0.001), higher burden of enlarged perivascular spaces (EPVS) in centrum semiovale (p < 0.001) and more frequently presented cortical superficial siderosis (cSS; p < 0.001). ICH recurrence in patients with CAA was 12.7 per 100 person-years, and no recurrence was observed in patients without CAA. Variables associated with ICH recurrence in the whole population were age (hazard ratio [HR] per 1-year increment = 1.05, 95% CI 1.00–1.11, p = 0.046), presence of disseminated cSS (HR 3.32, 95% CI 1.09–10.15, p = 0.035) and burden of EPVS in the centrum semiovale (HR per 1-point increment = 1.80, 95% CI 1.04–3.12, p = 0.035). Conclusions: This study confirms a higher ICH recurrence risk in patients with CAA-related ICH and suggests that age, disseminated cSS, and burden of EPVS in the centrum semiovale are associated with ICH recurrence.

New horizons: managing antithrombotic dilemmas in patients with cerebral amyloid angiopathy.

Cerebral amyloid angiopathy (CAA) most commonly presents with lobar intracerebral haemorrhage, though also with transient focal neurological episodes, cognitive impairment, as an incidental finding and rarely acutely or subacutely in patients developing an immune response to amyloid. Convexity subarachnoid haemorrhage, cortical superficial siderosis and lobar cerebral microbleeds are the other signature imaging features. The main implications of a diagnosis are the risk of intracerebral haemorrhage and frequent co-existence of antithrombotic indications. The risk of intracerebral haemorrhage varies by phenotype, being highest in patients with transient focal neurological episodes and lowest in patients with isolated microbleeds. There is only one relevant randomised controlled trial to CAA patients with antithrombotic indications: RESTART showed that in patients presenting with intracerebral haemorrhage while taking antiplatelets, restarting treatment appeared to reduce recurrent intracerebral haemorrhage and improve outcomes. Observational and indirect data are reviewed relevant to other scenarios where there are antithrombotic indications. In patients with a microbleed-only phenotype, the risk of ischaemic stroke exceeds the risk of intracerebral haemorrhage at all cerebral microbleed burdens. In patients with atrial fibrillation (AF), left atrial appendage occlusion, where device closure excludes the left atrial appendage from the circulation, can be considered where the risk of anticoagulation seems prohibitive. Ongoing trials are testing the role of direct oral anticoagulant (DOACs) and left atrial appendage occlusion in patients with intracerebral haemorrhage/AF but in the interim, treatment decisions will need to be individualised and remain difficult.

Cortical superficial siderosis in the general population: The Framingham Heart and Rotterdam studies.

We aimed to characterize cortical superficial siderosis, its determinants and sequel, in community-dwelling older adults. The sample consisted of Framingham (n = 1724; 2000-2009) and Rotterdam (n = 4325; 2005-2013) study participants who underwent brain MRI. In pooled individual-level analysis, we compared baseline characteristics in patients with cortical superficial siderosis to two reference groups: (i) persons without hemorrhagic MRI markers of cerebral amyloid angiopathy (no cortical superficial siderosis and no microbleeds) and (ii) those with presumed cerebral amyloid angiopathy based on the presence of strictly lobar microbleeds but without cortical superficial siderosis. Among a total of 6049 participants, 4846 did not have any microbleeds or cortical superficial siderosis (80%), 401 had deep/mixed microbleeds (6.6%), 776 had strictly lobar microbleeds without cortical superficial siderosis (12.8%) and 26 had cortical superficial siderosis with/without microbleeds (0.43%). In comparison to participants without microbleeds or cortical superficial siderosis and to those with strictly lobar microbleeds but without cortical superficial siderosis, participants with cortical superficial siderosis were older (OR 1.09 per year, 95% CI 1.05, 1.14; p < 0.001 and 1.04, 95% CI 1.00, 1.09; p = 0.058, respectively), had overrepresentation of the APOE ɛ4 allele (5.19, 2.04, 13.25; p = 0.001 and 3.47, 1.35, 8.92; p = 0.01), and greater prevalence of intracerebral hemorrhage (72.57, 9.12, 577.49; p < 0.001 and 81.49, 3.40, >999.99; p = 0.006). During a mean follow-up of 5.6 years, 42.4% participants with cortical superficial siderosis had a stroke (five intracerebral hemorrhage, two ischemic strokes and four undetermined strokes), 19.2% had transient neurological deficits and 3.8% developed incident dementia. Our study adds supporting evidence to the association between cortical superficial siderosis and cerebral amyloid angiopathy within the general population. Community-dwelling persons with cortical superficial siderosis may be at high risk for intracerebral hemorrhage and future neurological events.

Novel in vivo depiction of optic nerves hemorrhages in child abuse: a 3D-SWI pilot study

PurposeUntil now, the diagnosis of optic nerves hemorrhages in abusive head trauma (AHT) has been obtained only in the postmortem setting. The aim of the IRB-approved study was to assess the presence of optic nerves hemorrhages in AHT patients using 3D-SWI.MethodsThirteen children with a final confirmed multidisciplinary diagnosis of AHT underwent coronal and axial 3D-SWI imaging of the orbits. The presence of optic nerve sheath (ONS) hemorrhages was defined by thickening and marked 3D-SWI hypointensity of the ONS, resulting in mass effect upon the CSF space. Optic nerve (ON) hemorrhages were defined by areas of susceptibility artifacts in the ON parenchyma. Superficial siderosis was defined by susceptibility artifact coating the ON. Furthermore, data about post-traumatic deformity of the ONS at the head of the optic nerve were collected.ResultsThe average age of the population was 7.9 ± 5.9 months old. The average GCS was 11.8 ± 4.5. The male to female ratio was 7:6. ONS hemorrhages were identified in 69.2% of cases. Superficial siderosis and ON hemorrhages were identified in 38.5 and 76.9% of cases, respectively. 3D-SWI also depicted traumatic deformity of the ONS at the level of the optic nerve head in 10 cases (76.9%). No statistical correlations were identified between RetCam findings and 3D-SWI findings or GCS and ON hemorrhages.ConclusionThis research shows that dedicated MRI with volumetric SWI of the orbits can depict hemorrhages in the ON, ONS, and ONS injury, in AHT victims.

Frailty, MRI, and FDG-PET Measures in an Australian Memory Clinic Cohort

Given that the global population is aging, the number of age-related syndromes, such as frailty, is expected to rise in conjunction. Frailty is characterized by the loss of homeostatic reserve, rendering the individual vulnerable to poor health outcomes. Many biological mechanisms have been proposed to contribute to frailty. However, few studies have assessed the associations between frailty and brain diseases or neuroimaging biomarkers.Aims: The aims of this study were to measure the prevalence of frailty in a memory clinic and to examine associations between frailty and brain changes found on magnetic resonance imaging (MRI) and 18-F deoxyglucose (FDG) positron emission tomography (PET) in memory clinic attendees.Methods: A 54-items Frailty Index was retrospectively assessed for all clinic attendees from 2014. Frailty was defined as FI > 0.25. MR images were analyzed for stroke, cerebral small vessel disease [CSVD, including cerebral microbleeds (CMBs), cortical superficial siderosis (CSS), and white matter hyperintensity (WMH)], and neurodegenerative changes [MRI: mesial temporal atrophy (MTA), FDG-PET: regional hypometabolism], blind to clinical findings.Results: There were 209 clinic attendees in 2014, of whom 121 had MRI performed. The prevalence of frailty (using FI) in the memory clinic in 2014 was 38.3% overall (patients without MRI: 43.2%, patients with MRI 34.7%, p = 0.25). Frailty was associated with presence of deep WMH, increased severity of periventricular WMH, and presence of CSS, but not neurodegeneration markers (MTA atrophy/FDG-PET hypometabolism).Conclusion: The findings support the idea that previously reported associations between frailty and imaging evidence of CSVD in other cohorts are also relevant to the Australian clinic setting. Given that a large proportion of memory clinic attendees are frail, there may be opportunities for interventions to reduce preventable adverse health outcomes, such as falls and fractures, and reduce the prevalence and impact of frailty in this cohort.

Superficial siderosis of the central nervous system associated with ventral dural defects: bleeding from the epidural venous plexus.

Superficial siderosis of the central nervous system is a rare intractable disease induced by chronic subarachnoid hemorrhage. Neurological deficits, such as cerebellar ataxia and hearing difficulties, gradually progress if left undiagnosed. Hemosiderin deposition is irreversible because standard medical treatment has not yet been established. Interventions at the source of bleeding may be the key to a preferable outcome of treatment for chronic subarachnoid hemorrhage; however, the source is not clear in many cases. Among the consecutive cases diagnosed with a spontaneous cerebrospinal fluid (CSF) leak, cases of superficial siderosis associated with a CSF leak due to a ventral dural defect were retrospectively analyzed. Among 77 cases of a CSF leak, 7 cases (9%) of superficial siderosis were identified (median age of 59years, male, 4 cases). Defects were diagnosed on 1-mm sliced fast imaging employing steady-state acquisition MRI (n = 5), conventional myelographic CT (n = 1), or dynamic myelographic CT (n = 1) at high thoracic levels (T1-T4). All defects were repaired by direct neurosurgery. During surgery, continuous bleeding from the epidural veins of the internal vertebral venous plexus was identified as the source of subarachnoid hemorrhage. Epidural CSF pulsations through the defect prevented clot formation by the epidural veins. Dural repair stopped free communication between the subarachnoid and epidural spaces, leading to the disappearance of chronic subarachnoid hemorrhage. Bleeding from the epidural venous plexus may be the cause of superficial siderosis associated with ventral dural defects. Neurosurgical repair may stop the progression of this condition.

Spontaneous intracranial hypotension and Superficial Siderosis: closely linked diseases? A new concept of management

Spontaneous intracranial hypotension and Superficial Siderosis: closely linked diseases? A new concept of management

A case of sensorineural hearing loss due to superficial siderosis that improved with corticosteroids

A case of sensorineural hearing loss due to superficial siderosis that improved with corticosteroids

Donanemab (LY3002813) Phase 1b Study in Alzheimer\u2019s Disease: Rapid and Sustained Reduction of Brain Amyloid Measured by Florbetapir F18 Imaging

BackgroundDonanemab (LY3002813) is an IgG1 antibody directed at an N-terminal pyroglutamate of amyloid beta epitope that is present only in brain amyloid plaques.ObjectivesTo assess effects of donanemab on brain amyloid plaque load after single and multiple intravenous doses, as well as pharmacokinetics, safety/tolerability, and immunogenicity.DesignPhase 1b, investigator- and patient-blind, randomized, placebo-controlled study.SettingPatients recruited at clinical research sites in the United States and Japan.Participants61 amyloid plaque-positive patients with mild cognitive impairment due to Alzheimer’s disease and mild-to-moderate Alzheimer’s disease dementia.InterventionSix cohorts were dosed with donanemab: single dose 10-, 20- or 40- mg/kg (N = 18), multiple doses of 10-mg/kg every 2 weeks for 24 weeks (N = 10), and 10- or 20-mg/kg every 4 weeks for 72 weeks (N=18) or placebo (N = 15).MeasurementsBrain amyloid plaque load, using florbetapir positron emission tomography, was assessed up to 72 weeks. Safety was evaluated by occurrence of adverse events, magnetic resonance imaging, electrocardiogram, vital signs, laboratory testing, neurological monitoring, and immunogenicity.ResultsTreatment with donanemab resulted in rapid reduction of amyloid, even after a single dose. By 24 weeks, amyloid positron emission tomography mean changes from baseline for single donanemab doses in Centiloids were: −16.5 (standard error 11.22) 10-mg/kg intravenous; 40.0 (standard error 11.23) 20 mg/kg intravenous; and −49.6 (standard error 15.10) 40-mg/kg intravenous. Mean reduction of amyloid plaque in multiple dose cohorts by 24 weeks in Centiloids were: 55.8 (standard error 9.51) 10-mg/kg every 2 weeks; −50.2 (standard error 10.54) 10-mg/kg every 4 weeks; and −58.4 (standard error 9.66) 20-mg/kg every 4 weeks. Amyloid on average remained below baseline levels up to 72 weeks after a single dose of donanemab. Repeated dosing resulted in continued florbetapir positron emission tomography reductions over time compared to single dosing with 6 out of 28 patients attaining complete amyloid clearance within 24 weeks. Within these, 5 out of 10 patients in the 20 mg/kg every 4 weeks cohort attained complete amyloid clearance within 36 weeks. When dosing with donanemab was stopped after 24 weeks of repeat dosing in the 10 mg every 2 weeks cohort, florbetapir positron emission tomography reductions were sustained up to 72 weeks. For the single dose cohorts on day 1, dose proportional increases in donanemab pharmacokinetics were observed from 10 to 40 mg/kg. Dose proportional increases in pharmacokinetics were also observed at steady state with the multiple dose cohorts. Donanemab clearance was comparable across the dose levels. Mean donanemab elimination-halflife following 20 mg/kg single dose was 9.3 days with range of 5.6 to 16.2 days. Greater than 90% of patients had positive treatment-emergent antidrug antibodies with donanemab. However, overall, the treatment-emergent antidrug antibodies did not have a significant impact on pharmacokinetics. Donanemab was generally well tolerated. Amongst the 46 participants treated with donanemab, the following amyloid-related imaging abnormalities, common to the drug class, were observed: 12 vasogenic cerebral edema events (12 [19.7%] patients), 10 cerebral microhemorrhage events (6 [13.0%] patients), and 2 superficial siderosis events (2 [4.3%] patients).ConclusionsSingle and multiple doses of donanemab demonstrated a rapid, robust, and sustained reduction up to 72 weeks in brain amyloid plaque despite treatment-emergent antidrug antibodies detected in most patients. Amyloid-related imaging abnormalities were the most common treatment-emergent event.

Vascular Risk Factors, Imaging, and Outcomes in Transient Ischemic Attack/Ischemic Stroke Patients with Neuroimaging Evidence of Probable/Possible Cerebral Amyloid Angiopathy.

Background In TIA/ischemic stroke patients, the clinical significance of lobar microbleeds potentially indicating cerebral amyloid angiopathy (CAA) is unknown. We assessed vascular risk factors and outcomes, including cognition, in TIA/ischemic stroke patients with neuroimaging evidence of probable/possible CAA. Methods This prospective cohort was conducted from August 2015 and January 2018 at 40 centers. 2625 participants were collected. Eligible participants were aged at least 55 years. Montreal Cognitive Assessment (MoCA) score is less than or equal to 26. A total of 1620 patients were included. 1604 (99.0%) and 1582 (97.7%) participants are followed up at 3 and 12 months. The primary outcomes were death or disability (mRS score, 3-6) and Montreal Cognitive Assessment (MoCA) at 3 months and 12 months. Demographic and vascular risk factors were measured at baseline (smoking, alcohol, diabetes, atrial fibrillation, hypertension, hypercholesterolemia, coronary artery disease, ischemic stroke, and transient ischemic attack). Blood samples were collected within 24 hours of admission. MRI was recommended for all patients. MoCA score was evaluated at baseline and follow-up. Results In total, 291/1620 patients with ischemic stroke/TIA (32.7% female and mean age, 67.8 years) had neuroimaging evidence of probable/possible CAA. Higher age, history of hypertension, atrial fibrillation, ischemic stroke, alcohol, and high glucose at the admission were more common in the patients. Mean MoCA changed from 21.4 at 3 months (SD 5.2) to 22.3 at 12 months (SD 4.7), difference 0.3 (SD 3.8). At the 3-month and 12-month follow-up, there were significant differences in age, education level, and sex among different cognitive groups. Higher age, lower education (less than high school), and female sex were the predictors of changing in MoCA score from 3 months to 12 months. Moreover, age (more than 66 years) and education (less than high school) are strongly associated with MoCA at 3- and 12-month follow-up. 30 of 286 (10.5%) and 37 of 281 (13.2%) patients had poor outcome of death or disability (modified Rankin Scale score, 3-6) at follow-up 3 and 12 months. Cortical superficial siderosis (cSS) was associated with higher mRS at follow-up. cSS status, cSS count 1-2, cSS strictly lobar, and strictly deep might be the risks of outcomes in adjusted analyses. Conclusion This study suggested that an increasing number of vascular risk factors and imaging markers were significantly associated with outcomes of TIA/ischemic stroke patients with CAA pattern. Male, young patients with high education should get better cognitive recovery.

The treatment for superficial siderosis

The treatment for superficial siderosis

Imaging diagnosis of superficial siderosis

Imaging diagnosis of superficial siderosis

Clinical symptoms of superficial siderosis

Clinical symptoms of superficial siderosis

Long-Term Vascular Outcomes in Patients With Mixed Location Intracerebral Hemorrhage and Microbleeds.

To determine whether mixed location intracerebral hemorrhages/microbleeds (mixed ICH) is a risk factor for vascular unfavorable outcome compared to cerebral amyloid angiopathy-related ICH (CAA-ICH) or strictly deep hypertensive ICH/microbleeds (HTN-ICH). A total of 300 patients with spontaneous ICH were included. Clinical data, neuroimaging markers, and follow-up outcomes (recurrent ICH, ischemic stroke, and vascular death) were compared among mixed ICH (n = 148), CAA-ICH (n = 32), and HTN-ICH (n = 120). The association between follow-up events and neuroimaging markers was explored using multivariable Cox regression models. Patients with mixed ICH were older (65.6 ± 12.1 years vs 58.1 ± 13.3 years, p < 0.001) than patients with HTN-ICH, but younger than patients with CAA-ICH (73.3 ± 13.8 years, p = 0.001). Compared to CAA-ICH, mixed ICH had similar incidence of vascular events (all p > 0.05). Compared to HTN-ICH, mixed ICH is associated with higher ICH recurrence (hazard ratio [HR] 3.0, 95% confidence interval [CI] 1.2-7.7), more ischemic stroke (HR 8.2, 95% CI 1.0-65.8), and vascular composite outcome (HR 3.5, 95% CI 1.5-8.2) after adjustment for age and sex. In patients with mixed ICH, the presence of cortical superficial siderosis (cSS) is associated the development of ICH recurrence (HR 4.8, 95% CI 1.0-23.2), ischemic stroke (HR 8.8, 95% CI 1.7-45.5), and vascular composite outcome (HR 6.2, 95% CI 1.9-20.2). The association between cSS and ischemic stroke (p = 0.01) or vascular composite outcome (p = 0.003) remained significant after further adjustment for other radiologic markers. Mixed ICH harbors higher risk of unfavorable vascular outcome than HTN-ICH. Presence of cSS in mixed ICH independently predicts vascular event, suggesting the contribution of detrimental effect due to coexisting CAA.

Definitions and MR imaging of duropathies

Kumar defined duropathies as disorders with dural defects-related cerebrospinal fluid leaks, particularly of spinal anterior dura mater, Superficial (hemo) siderosis (SS) and multisegemental amyotrophy (MSAM) were included in duropathies. Dural defects of SS had two types; one was incomplete closure of the dura in the spinal and cranial operations, the other was a spontaneous defect in the spinal anterior dura mater. In a majority of SS patients, spontaneous dural defects were detected at the levels of C7/Th1 to Th2/Th3 on axial FIESTA (fast imaging employing steady state acquisition) images. Similarly, dural defects in our 6 cases with MSAM were showed at C7/Th1 to Th2/Th3. Axial FIESTA images were crucial on MR imaging. T2 weighted images demonstrated abnormal hyperintense lesions in both anterior horns at the level of C3 spinal cord in all of 7 patients with MSAM. A dural defect in one case was not found.

Spinal dural leaks in patients with infratentorial superficial siderosis of the central nervous system-Refinement of a diagnostic algorithm.

Superficial siderosis of the central nervous system is a sporadic finding in magnetic resonance imaging, resulting from recurrent bleedings into the subarachnoid space. This study aimed to determine the frequency of spinal dural cerebrospinal fluid (CSF) leaks amongst patients with a symmetric infratentorial siderosis pattern. In all, 97,733 magnetic resonance images performed between 2007 and 2018 in our neurocenter were screened by a keyword search for "hemosiderosis" and "superficial siderosis." Siderosis patterns on brain imaging were classified according to a previously published algorithm. Potential causative intracranial bleeding events were also assessed. Patients with a symmetric infratentorial siderosis pattern but without causative intracranial bleeding events in history were prospectively evaluated for spinal pathologies. Forty-two patients with isolated supratentorial siderosis, 30 with symmetric infratentorial siderosis and 21 with limited (non-symmetric) infratentorial siderosis were identified. Amyloid angiopathy and subarachnoid hemorrhage were causes for isolated supratentorial siderosis. In all four patients with a symmetric infratentorial siderosis pattern but without a causative intracranial bleeding event in history, spinal dural abnormalities were detected. Dural leaks were searched for in patients with symmetric infratentorial siderosis and a history of intracranial bleeding event without known bleeding etiology, considering that spinal dural CSF leaks themselves may also cause intracranial hemorrhage, for example by inducing venous thrombosis due to low CSF pressure. Thereby, one additional spinal dural leak was detected. Persisting spinal dural CSF leaks can frequently be identified in patients with a symmetric infratentorial siderosis pattern. Diagnostic workup in these cases should include magnetic resonance imaging of the whole spine.

Amyloid angiopathy may contribute to white‐matter hyperintensities in Alzheimer’s disease

AbstractBackgroundCerebral amyloid angiopathy (CAA) is characterised by the accumulation of amyloid‐b (Aβ) in cerebral vessels and is often coexistent with Alzheimer’s disease (AD). However, the overlap between CAA and AD and the contribution of CAA pathology to cerebrovascular lesions are not well understood. We hypothesize that in subjects with high Aβ load, the presence of imaging markers of CAA would be associated with greater white matter hyperintensities (WMH) burden.MethodData used in the preparation of this article was obtained from the Australian Imaging Biomarkers and Lifestyle flagship study of ageing (AIBL). See www.aibl.csiro.au. We analysed MRI (SWI and FLAIR) and 11C‐PiB‐PET data from 98 cognitively normal (CN), 34 mild‐cognitive impairment (MCI) and 38 AD participants. Subjects were classified as being Aβ+ if their Aβ load was above 20 centiloid.SWI images were manually read for lobar microbleeds (LMB) and superficial siderosis. Subjects were classified as probable‐CAA (PCAA, 2 or more LMB or siderosis), possible‐CAA (SCAA, single LMB or siderosis) or non‐CAA (NCAA) based on the modified Boston criteria. Subjects classified as SCAA (n = 24) were excluded from further analysis since literature shows this group to be heterogenous and having low incidence of CAA pathology. WMH were automatically quantified on FLAIR. Group comparisons of WMH load were made using Kruskal Wallis rank test. A GLM was performed comparing WMH (log10 transformed) and CAA/ Aβ+ classification with age, intracranial volume, gender, APOE‐ε4 genotype and use of anti‐platelet or anticoagulant medication modelled as covariates.ResultSignificantly higher WMH volume was observed in PCAA (n = 17) than NCAA (n = 129) (p‐value = 0.021, d = 0.36). When amyloid status was considered, PCAA/Aβ+ (n = 15) subjects had a significantly higher WMH load than NCAA/Aβ+ (n = 57) subjects (p‐value = 0.012, d = 0.57) and NCAA/Aβ‐ (n = 72) subjects (p‐value = 0.0006, d = 0.76) (Figure 1). PCAA/Aβ‐ (n = 2) were removed from further analysis. GLM results showed a significant association of WMH with PCAA/Aβ+ as compared to NCAA/Aβ+ (p‐value = 0.02, beta = 0.322 [0.056,0.588]).ConclusionOur findings suggest that CAA may contribute to WMH burden in subjects with high Aβ load. Further studies are required to validate our observations and characterise the contributions of CAA compared to small vessel disease associated with traditional risk factors towards the phenotype of AD.

Neuropathological correlates of cortical superficial siderosis in cerebral amyloid angiopathy

AbstractBackgroundCortical superficial siderosis (cSS) is an established hemorrhagic neuroimaging marker of cerebral amyloid angiopathy (CAA) and emerging as a strong independent risk factor for future lobar intracerebral hemorrhage. However, the underlying neuropathological correlates and pathophysiological mechanisms of cSS remain elusive.MethodFourteen autopsy cases with CAA (mean age at death 73 years, 9 males) and three controls (mean age at death 91 years, 1 male) were included. Intact formalin‐fixed cerebral hemispheres were scanned on a 3 tesla MRI scanner. cSS was assessed on ex vivo gradient echo and turbo spin echo MRI sequences and compared to findings on available in vivo MRI. Subsequently, eleven representative areas in four cases with available in vivo MRI scans were sampled for histopathological verification of MRI‐defined cSS. In addition, samples were taken from pre‐defined standard areas of the brain, blinded to MRI findings. Serial sections were stained for H&amp;E and Perls’ Prussian blue, and immunohistochemistry was performed against Aβ and GFAP.ResultcSS was present on ex vivo MRI in 8/14 cases and 0/3 controls. Histopathologically, cSS corresponded to Iron‐positive hemosiderin deposits in the subarachnoid space and superficial cortical layers, indicative of chronic bleeding events originating from the leptomeningeal vessels (Figure 1). Increased severity of cSS was associated with upregulation of reactive astrocytes. Next, cSS and CAA pathology were assessed on a total of 65 sections from MRI‐targeted and untargeted samples. Moderate‐to‐severe cSS was associated with concentric splitting (an advanced form of CAA‐related vascular damage) of the walls of leptomeningeal vessels (p&lt;0.0001), but reduced CAA severity in cortical vessels (p=0.048). Moderate‐to‐severe cSS was associated with the presence of microinfarcts (p=0.025), though not microbleeds (p=0.973).ConclusioncSS on MRI corresponds to Iron‐positive depositions in the superficial cortical layers, representing the chronic manifestation of bleeding episodes from leptomeningeal vessels. cSS appears to be the result predominantly of advanced CAA of the leptomeningeal vessels and may trigger secondary ischemic injury in affected areas.