Objective: We hypothesized that florbetapir, a Food and Drug Administration-approved PET tracer, could distinguish cerebral amyloid angiopathy (CAA)-related intracerebral hemorrhage (ICH) from ...hypertensive ICH (HTN-ICH). Methods: We prospectively enrolled survivors of primary ICH related to probable CAA (per Boston Criteria, n = 10) and HTN-ICH (n = 9) without dementia. All patients underwent florbetapir-PET and multimodal MRI, and patients with CAA had additional Pittsburgh compound B (PiB) PET. Amyloid burden was assessed quantitatively (standard uptake value ratio SUVR) and visually classified as positive or negative. Results: The CAA and HTN-ICH groups had similar age (66.9 vs 67.1), sex, and leukoaraiosis volumes (31 vs 30 mL, all p> 0.8). Florbetapir uptake and PiB retention strongly correlated in patients with CAA both globally within cerebral cortex (r= 0.96, p< 0.001) and regionally in lobar cortices (all r> 0.8, all p< or = 0.01). Mean global cortical florbetapir uptake was substantially higher in CAA than HTN-ICH (SUVR: 1.41 + or - 0.17 vs 1.15 + or - 0.08, p= 0.001), as was mean occipital SUVR (1.44 + or - 0.12 vs 1.17 + or - 0.08, p< 0.001), even after correcting for global SUVR (p= 0.03). Visual rating for positive/negative florbetapir demonstrated perfect interrater agreement (k = 1) and was positive for all 10 patients with CAA vs 1 of 9 HTN-ICH patients (sensitivity 100%, specificity 89%). Conclusions: Florbetapir appears to label vascular amyloid in patients with CAA-related ICH. The approved florbetapir binary visual reading method can have diagnostic value in appropriate clinical settings.
OBJECTIVE:To assess MRI-visible enlarged perivascular spaces (EPVS) burden and different topographical patterns (in the centrum semiovale CSO and basal ganglia BG) in 2 common ...microangiopathiescerebral amyloid angiopathy (CAA) and hypertensive arteriopathy (HA).
METHODS:Consecutive patients with spontaneous intracerebral hemorrhage (ICH) from a prospective MRI cohort were included. Small vessel disease MRI markers, including cerebral microbleeds (CMBs), cortical superficial siderosis (cSS), and white matter hyperintensities (WMH), were rated. CSO-EPVS/BG-EPVS were assessed on a validated 4-point visual rating scale (0 = no EPVS, 1 = <10, 2 = 11–20, 3 = 21–40, and 4 = >40 EPVS). We tested associations of predefined high-degree (score >2) CSO-EPVS and BG-EPVS with other MRI markers in multivariable logistic regression. We subsequently evaluated associations with CSO-EPVS predominance (i.e., CSO-EPVS > BG-EPVS) and BG-EPVS predominance pattern (i.e., BG-EPVS > CSO-EPVS) in adjusted multinomial logistic regression (reference group, BG-EPVS = CSO-EPVS).
RESULTS:We included 315 patients with CAA-ICH and 137 with HA-ICH. High-degree CSO-EPVS prevalence was greater in CAA-related ICH vs HA-related ICH (43.8% vs 17.5%, p < 0.001). In multivariable logistic regression, high-degree CSO-EPVS was associated with lobar CMB (odds ratio OR 1.33, 95% confidence interval CI 1.10–1.61, p = 0.003) and cSS (OR 2.08, 95% CI 1.30–3.32, p = 0.002). Deep CMBs (OR 2.85, 95% CI 1.75–4.64, p < 0.0001) and higher WMH volume (OR 1.02, 95% CI 1.01–1.04, p = 0.010) were predictors of high-degree BG-EPVS. A CSO-EPVS–predominant pattern was more common in CAA-ICH than in HA-ICH (75.9% vs 39.4%, respectively, p < 0.0001). CSO-PVS predominance was associated with lobar CMB burden and cSS, while BG-EPVS predominance was associated with HA-ICH and WMH volumes.
CONCLUSIONS:Different patterns of MRI-visible EPVS provide insights into the dominant underlying microangiopathy type in patients with spontaneous ICH.
Summary Background Previous work suggests that impairments of cerebrovascular flow or reactivity might be early markers of cerebral amyloid angiopathy (CAA). Hereditary cerebral haemorrhage with ...amyloidosis–Dutch type (HCHWA-D) is a genetic form of CAA that can be diagnosed before the onset of clinical symptoms by DNA testing. We aimed to investigate whether haemodynamic measures are decreased in presymptomatic and symptomatic HCHWA-D mutation carriers compared with healthy controls. Methods In this case-control study, we included presymptomatic and symptomatic HCHWA-D mutation carriers diagnosed through genetic testing and recruited through the HCHWA-D patient association (Katwijk, Netherlands) and the outpatient clinic of the Department of Neurology of the Leiden University Medical Center (Leiden, Netherlands), and healthy controls. We measured regional cerebral blood flow (rCBF) using pseudo-continuous arterial spin labelling. Quantitative flow was measured by phase-contrast magnetic resonance angiography of the cerebropetal vessels. Vascular reactivity was established by measuring changes in blood-oxygen-level-dependent (BOLD) signal after visual stimulation. Data from presymptomatic and symptomatic individuals were compared with healthy controls using mixed-model regression analysis. Findings Between May 15, 2012, and December 22, 2015, we investigated cross-sectional imaging data from 27 HCHWA-D mutation carriers (12 presymptomatic and 15 symptomatic) and 33 healthy controls. Compared with controls, symptomatic HCHWA-D carriers had significantly decreased cortical grey matter rCBF in the occipital lobe (mean difference −11·1 mL/100 g per min, 95% CI −2·8 to −19·3; uncorrected p=0·010) and decreased flux in the basilar artery (mean difference −0·9 mL/s, 95% CI −1·5 to −0·2; uncorrected p=0·019). However, we noted no changes in rCBF and flux in presymptomatic carriers compared with controls. Vascular reactivity was significantly decreased in the occipital lobe in both presymptomatic (mean BOLD change 1·1% SD 0·5, mean difference −0·4% change, 95% CI −0·7 to −0·2; p=0·001; mean time to baseline 10·1 s SD 7·6, mean difference 4·6 s, 95% CI 0·4 to 8·8; p=0·032) and symptomatic carriers (mean BOLD change 0·4% SD 0·1, mean difference −0·9%, 95% CI −1·1 to −0·6; p<0·0001; mean time to baseline 20·3 s SD 8·4, mean difference 13·1 s, 95% CI 9·4 to 16·9; p<0·0001) compared with controls; however, the difference in mean time to peak was only significant for symptomatic carriers (mean difference 12·2 s, 95% CI 8·6 to 15·9; p<0·0001). Interpretation Our findings suggest that determination of vascular reactivity might be a useful biomarker for early detection of vascular amyloid pathology in sporadic CAA, and a biomarker of efficacy in future intervention trials. Our data indicate that vascular reactivity measurements might be useful for differential diagnosis in dementia to determine the vascular component. Funding USA National Institutes of Health.
OBJECTIVE:To investigate whether cortical superficial siderosis (cSS) is associated with increased risk of future first-ever symptomatic lobar intracerebral hemorrhage (ICH) in patients with cerebral ...amyloid angiopathy (CAA) presenting with neurologic symptoms and without ICH.
METHODS:Consecutive patients meeting modified Boston criteria for probable CAA in the absence of ICH from a single-center cohort were analyzed. cSS and other small vessel disease MRI markers were assessed according to recent consensus recommendations. Patients were followed prospectively for future incident symptomatic lobar ICH. Prespecified Cox proportional hazard models were used to investigate cSS and first-ever lobar ICH risk adjusting for potential confounders.
RESULTS:The cohort included 236 patients with probable CAA without lobar ICH at baseline. cSS prevalence was 34%. During a median follow-up of 3.26 years (interquartile range 1.42–5.50 years), 27 of 236 patients (11.4%) experienced a first-ever symptomatic lobar ICH. cSS was a predictor of time until first ICH (p = 0.0007, log-rank test). The risk of symptomatic ICH at 5 years of follow-up was 19% (95% confidence interval CI 11%–32%) for patients with cSS at baseline vs 6% (95% CI 3%–12%) for patients without cSS. In multivariable Cox regression models, cSS presence was the only independent predictor of increased symptomatic ICH risk during follow-up (HR 4.04; 95% CI 1.73–9.44, p = 0.001), after adjusting for age, lobar cerebral microbleeds burden, and white matter hyperintensities.
CONCLUSIONS:cSS is consistently associated with an increased risk of future lobar ICH in CAA with potentially important clinical implications for patient care decisions such as antithrombotic use.
BACKGROUND AND PURPOSE—Lobar microbleeds suggestive of cerebral amyloid angiopathy (CAA) are often identified on MRI in the absence of lobar intracerebral hemorrhage (ICH). We compared the baseline ...characteristics and risk of subsequent ICH among such patients to those presenting with CAA-related lobar ICH.
METHODS—Clinical data (demographics, risk factors), apolipoprotein E genotype, neuroimaging markers of CAA severity (microbleed counts, leukoaraiosis volume), and clinical outcomes (incidence rates of ICH and death during a mean follow-up of 5.3±3.8 years) were compared between 63 patients enrolled because of incidentally found microbleeds and 316 with CAA-related ICH, in our prospectively enrolled cohort. Predictors of incident ICH were explored in the microbleed-only patients using multivariable Cox regression models.
RESULTS—Microbleed-only patients shared similar demographic, apolipoprotein E, and vascular risk profiles with lobar ICH patients, but had more lobar microbleeds (median, 10 versus 2; P<0.001) and higher leukoaraiosis volumes (median, 31 versus 23 mL; P=0.02). Microbleed-only patients had a nontrivial incidence rate of ICH, not different from patients presenting with ICH (5 versus 8.9 per 100 person-years; adjusted hazard ratio, 0.58; 95% confidence interval, 0.31–1.06; P=0.08). Microbleed-only patients had a higher mortality rate (hazard ratio, 1.67; 95% confidence interval, 1.1–2.6) compared with ICH survivors. Warfarin use and increasing age were independent predictors of future ICH among microbleed-only patients after correction for other covariates.
CONCLUSIONS—Patients presenting with isolated lobar microbleeds on MRI have a genetic, neuroimaging, and hemorrhagic risk profile suggestive of severe CAA pathology. They have a substantial risk of incident ICH, potentially affecting decisions regarding anticoagulation in clinical situations.
We explored whether high-degree magnetic resonance imaging–visible perivascular spaces in centrum semiovale (CSO) are more prevalent in cerebral amyloid angiopathy (CAA) than hypertensive small ...vessel disease and their relationship to brain amyloid retention in patients with primary intracerebral hemorrhage (ICH).
One hundred and eight spontaneous ICH patients who underwent magnetic resonance imaging and Pittsburgh compound B were enrolled. Topography and severity of enlarged perivascular spaces were compared between CAA-related ICH (CAA-ICH) and hypertensive small vessel disease–related ICH (non-CAA ICH). Clinical and image characteristics associated with high-degree perivascular spaces were evaluated in univariate and multivariable analyses. Univariate and multivariable models were performed to evaluate associations between the severity of perivascular spaces in CSO and amyloid retention in CAA-ICH and non–CAA-ICH cases.
Patients with CAA-ICH (n=29) and non–CAA-ICH (n=79) had similar prevalence of high-degree perivascular spaces in CSO (44.8% versus 36.7%; P=0.507) and in basal ganglia (34.5% versus 51.9%; P=0.131). High-degree perivascular spaces in CSO were independently associated with the presence of lobar microbleed (odds ratio, 3.0 95% CI, 1.1–8.0; P=0.032). The amyloid retention was higher in those with high-degree than those with low-degree CSO-perivascular spaces in CAA-ICH (global Pittsburgh compound B standardized uptake value ratio, 1.55 1.33–1.61 versus 1.13 1.01–1.48; P=0.003) but not in non–CAA-ICH. In CAA-ICH, the association between cerebral amyloid retention and the degree of perivascular spaces in CSO remained significant after adjustment for age and lobar microbleed number (P=0.004).
Although high-degree magnetic resonance imaging–visible perivascular spaces are equally prevalent between CAA-ICH and non–CAA-ICH in the Asian cohort, the severity of magnetic resonance imaging–visible CSO-perivascular spaces may be an indicator of higher brain amyloid deposition in patients with CAA-ICH.
BACKGROUND AND PURPOSE—Acute leukocytosis is a well-established response to intracerebral hemorrhage (ICH). Leukocytes, because of their interaction with platelets and coagulation factors, may in ...turn play a role in hemostasis. We investigated whether admission leukocytosis was associated with reduced bleeding after acute ICH.
METHODS—Consecutive patients with primary ICH were prospectively collected from 1994 to 2015 and retrospectively analyzed. We included subjects with a follow-up computed tomographic scan available and automated complete white blood cell count performed within 48 hours from onset. Baseline and follow-up hematoma volumes were calculated with semiautomated software, and hematoma expansion was defined as volume increase >30% or 6 mL. The association between white blood cell count and ICH expansion was investigated with multivariate logistic regression.
RESULTS—A total of 1302 subjects met eligibility criteria (median age, 75 years; 55.8% men), of whom 207 (15.9%) experienced hematoma expansion. Higher leukocyte count on admission was associated with reduced risk of hematoma expansion (odds ratio for 1000 cells increase, 0.91; 95% confidence interval, 0.86–0.96; P=0.001). The risk of hematoma expansion was inversely associated with neutrophil count (odds ratio, 0.90; 95% confidence interval, 0.85–0.96; P=0.001) and directly associated with monocyte count (odds ratio, 2.71; 95% confidence interval, 1.08–6.83; P=0.034). There was no association between lymphocyte count and ICH expansion (odds ratio, 0.96; 95% confidence interval, 0.79–1.17; P=0.718).
CONCLUSIONS—Higher admission white blood cell count is associated with lower risk of hematoma expansion. This highlights a potential role of the inflammatory response in modulating the coagulation cascade after acute ICH.
Cerebral amyloid angiopathy is a common neuropathological finding in the ageing human brain, associated with cognitive impairment. Neuroimaging markers of severe cerebral amyloid angiopathy are ...cortical microbleeds and microinfarcts. These parenchymal brain lesions are considered key contributors to cognitive impairment. Therefore, they are important targets for therapeutic strategies and may serve as surrogate neuroimaging markers in clinical trials. We aimed to gain more insight into the pathological basis of magnetic resonance imaging-defined microbleeds and microinfarcts in cerebral amyloid angiopathy, and to explore the pathological burden that remains undetected, by using high and ultra-high resolution ex vivo magnetic resonance imaging, as well as detailed histological sampling. Brain samples from five cases (mean age 85 ± 6 years) with pathology-proven cerebral amyloid angiopathy and multiple microbleeds on in vivo clinical magnetic resonance imaging were subjected to high-resolution ex vivo 7 T magnetic resonance imaging. On the obtained high-resolution (200 μm isotropic voxels) ex vivo magnetic resonance images, 171 microbleeds were detected compared to 66 microbleeds on the corresponding in vivo magnetic resonance images. Of 13 sampled microbleeds that were matched on histology, five proved to be acute and eight old microhaemorrhages. The iron-positive old microhaemorrhages appeared approximately four times larger on magnetic resonance imaging compared to their size on histology. In addition, 48 microinfarcts were observed on ex vivo magnetic resonance imaging in three out of five cases (two cases exhibited no microinfarcts). None of them were visible on in vivo 1.5 T magnetic resonance imaging after a retrospective analysis. Of nine sampled microinfarcts that were matched on histology, five were confirmed as acute and four as old microinfarcts. Finally, we explored the proportion of microhaemorrhage and microinfarct burden that is beyond the detection limits of ex vivo magnetic resonance imaging, by scanning a smaller sample at ultra-high resolution, followed by serial sectioning. At ultra-high resolution (75 μm isotropic voxels) magnetic resonance imaging we observed an additional 48 microbleeds (compared to high resolution), which proved to correspond to vasculopathic changes (i.e. morphological changes to the small vessels) instead of frank haemorrhages on histology. After assessing the serial sections of this particular sample, no additional haemorrhages were observed that were missed on magnetic resonance imaging. In contrast, nine microinfarcts were found in these sections, of which six were only retrospectively visible at ultra-high resolution. In conclusion, these findings suggest that microbleeds on in vivo magnetic resonance imaging are specific for microhaemorrhages in cerebral amyloid angiopathy, and that increasing the resolution of magnetic resonance images results in the detection of more 'non-haemorrhagic' pathology. In contrast, the vast majority of microinfarcts currently remain under the detection limits of clinical in vivo magnetic resonance imaging.
A subset of ischaemic stroke patients with atrial fibrillation (AF) have ischaemic stroke despite anticoagulation. We sought to determine the association between prestroke anticoagulant therapy and ...recurrent ischaemic events and symptomatic intracranial haemorrhage (sICH).
We included consecutive patients with acute ischaemic stroke and AF from the Initiation of Anticoagulation after Cardioembolic stroke (IAC) study from eight comprehensive stroke centres in the USA. We compared recurrent ischaemic events and delayed sICH risk using adjusted Cox regression analyses between patients who were prescribed anticoagulation (ACp) versus patients who were naïve to anticoagulation therapy prior to the ischaemic stroke (anticoagulation naïve).
Among 2084 patients in IAC, 1518 had prior anticoagulation status recorded and were followed for 90 days. In adjusted Cox hazard models, ACp was associated with some evidence of a higher risk higher risk of 90-day recurrent ischaemic events only in the fully adjusted model (adjusted HR 1.50, 95% CI 0.99 to 2.28, p=0.058) but not increased risk of 90-day sICH (adjusted HR 1.08, 95% CI 0.46 to 2.51, p=0.862). In addition, switching anticoagulation class was not associated with reduced risk of recurrent ischaemic events (adjusted HR 0.41, 95% CI 0.12 to 1.33, p=0.136) nor sICH (adjusted HR 1.47, 95% CI 0.29 to 7.50, p=0.641).
AF patients with ischaemic stroke despite anticoagulation may have higher recurrent ischaemic event risk compared with anticoagulation-naïve patients. This suggests differing underlying pathomechanisms requiring different stroke prevention measures and identifying these mechanisms may improve secondary prevention strategies.
PDF
