Sporadic cerebral amyloid angiopathy is a common, well-defined small vessel disease and a largely untreatable cause of intracerebral haemorrhage and contributor to age-related cognitive decline. The term ‘cerebral amyloid angiopathy’ now encompasses not only a specific cerebrovascular pathological finding, but also different clinical syndromes (both acute and progressive), brain parenchymal lesions seen on neuroimaging and a set of diagnostic criteria—the Boston criteria, which have resulted in increasingly detected disease during life. Over the past few years, it has become clear that, at the pathophysiological level, cerebral amyloid angiopathy appears to be in part a protein elimination failure angiopathy and that this dysfunction is a feed-forward process, which potentially leads to worsening vascular amyloid-β accumulation, activation of vascular injury pathways and impaired vascular physiology. From a clinical standpoint, cerebral amyloid angiopathy is characterized by individual focal lesions (microbleeds, cortical superficial siderosis, microinfarcts) and large-scale alterations (white matter hyperintensities, structural connectivity, cortical thickness), both cortical and subcortical. This review provides an interdisciplinary critical outlook on various emerging and changing concepts in the field, illustrating mechanisms associated with amyloid cerebrovascular pathology and neurological dysfunction.

Background Brain MRI parenchymal signal abnormalities have been in association with SARS-CoV-2. Purpose Describe the neuroimaging findings (excluding ischemic infarcts) in patients with severe COVI...

Cerebral amyloid angiopathy-related inflammation (CAA-ri) is an important diagnosis to reach in clinical practice because many patients with the disease respond to immunosuppressive therapy. Reliable noninvasive diagnostic criteria for CAA-ri would allow some patients to avoid the risk of brain biopsy. To test the sensitivity and specificity of clinical and neuroimaging-based criteria for CAA-ri. We modified the previously proposed clinicoradiological criteria and retrospectively analyzed clinical medical records and magnetic resonance imaging fluid-attenuated inversion recovery and gradient-echo scans obtained from individuals with CAA-ri and noninflammatory CAA. At 2 referral centers between October 1, 1995, and May 31, 2013, and between January 1, 2009, and December 31, 2011, participants included 17 individuals with pathologically confirmed CAA-ri and 37 control group members with pathologically confirmed noninflammatory CAA. The control group was further divided into those with past lobar intracerebral hemorrhage (ICH) (n = 21) and those with cerebral microbleeds only and no history of ICH (n = 16). The dates of our analysis were September 1, 2012, to August 31, 2015. The sensitivity and specificity of prespecified criteria for probable CAA-ri (requiring asymmetric white matter hyperintensities extending to the subcortical white matter) and possible CAA-ri (not requiring the white matter hyperintensities to be asymmetric). The 17 patients in the CAA-ri group were a mean (SD) of 68 (8) years and 8 (47%) were women. In the CAA-ri group, 14 of 17 (82%) met the criteria for both probable and possible CAA-ri. In the control group having noninflammatory CAA with lobar ICH, 1 of 21 (5%) met the criteria for possible CAA-ri, and none met the criteria for probable CAA-ri. In the control group having noninflammatory CAA with no ICH, 11 of 16 (69%) met the criteria for possible CAA-ri, and 1 of 16 (6%) met the criteria for probable CAA-ri. These findings yielded a sensitivity and specificity of 82% and 97%, respectively, for the probable criteria and a sensitivity and specificity of 82% and 68%, respectively, for the possible criteria. Our data suggest that a reliable diagnosis of CAA-ri can be reached from basic clinical and magnetic resonance imaging information alone, with good sensitivity and excellent specificity.

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 microangiopathies: cerebral 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 = 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.

Spontaneous intracerebral hemorrhage (ICH) is the most deadly type of stroke,¹ with an up to 40% mortality rate at 30 days and only one-fifth of the survivors being independent after 6 months.² Although many determinants of ICH outcome, such as location and baseline volume, are nonmodifiable at presentation,^3,4 clinically significant hematoma expansion, occurring in more than a third of patients with ICH,⁵ is an independent prognostic factor⁶ and a potential therapeutic target.^7-10 However, treatments aimed at limiting hemorrhage expansion have yet to yield improved outcomes in clinical trials.^7,11-13 Refining our ability to identify those patients who are most likely to benefit from expansion-targeted treatments could have important implications for clinical practice and future trials.¹¹