Deep Microbleeds Research Articles

Microalbuminuria is independently associated with deep or infratentorial brain microbleeds in hypertensive adults

Brain microbleeds (BMBs) detected on gradient echo T2*-weighted magnetic resonance imaging (GE-MRI) may be pathophysiologically linked to ischemic cerebral small-vessel disease (SVD) and increased risk of future hemorrhagic stroke. Chronic kidney disease (CKD) has been associated with the presence of BMBs in stroke patients. However, the relationship between CKD markers and BMBs in stroke-free populations is unknown. Two hundred and eighty-five hypertensive subjects (mean age 68.6 years) without neurological symptoms were enrolled from a hospital-based outpatient clinic and all participants underwent GE-MRI. We calculated urinary albumin/creatinine ratio (UACR) from morning spot urine and the estimated glomerular filtration rate (eGFR) in serum samples. Multivariate logistic regression analysis was used to evaluate the association between these kidney biomarkers and the presence and location of BMBs, controlling for age, sex, use of antihypertensive or antithrombotic drugs, and MRI findings. BMBs were observed in 48 (16.8%) patients. Median UACRs were significantly higher in patients with deep or infratentorial BMBs than in patients with pure lobar BMBs (54 vs. 17 mg/g creatinine, P = 0.04). No significant differences were found between eGFR levels and the location of BMBs. Microalbuminuria (UACR >30- ≤300 mg/g creatinine), but not low eGFR level was significantly associated with higher prevalence of deep or infratentorial BMBs (odds ratio (OR): 3.16, 95% confidence interval (CI): 1.34-7.44, P = 0.009) even after adjustment for potential confounding factors. Microalbuminuria is closely associated with the prevalence of deep or infratentorial BMBs in hypertensive patients. Our findings provide new insights into the association between risk factors and the distribution of BMBs.

Serum Lipid Levels and the Risk of Intracerebral Hemorrhage: The Rotterdam Study

Low serum total cholesterol levels are associated with an increased risk of symptomatic intracerebral hemorrhage and with presence of asymptomatic cerebral microbleeds. The relative contribution of lipid fractions to these associations is unclear and requires investigation. We determined whether serum HDL-cholesterol, LDL-cholesterol, and triglycerides are associated with risk of intracerebral hemorrhage and presence of cerebral microbleeds. Nine thousand sixty-eight stroke-free community-dwelling persons aged ≥55 were followed from baseline (1990-2001) up to January 1, 2009, of whom 85 suffered from intracerebral hemorrhage during follow-up. Brain MRI was carried out in 789 healthy participants, of whom 162 had cerebral microbleeds. Triglycerides were strongly and inversely associated with intracerebral hemorrhage, independently of HDL-cholesterol, LDL-cholesterol, and potential confounders [hazard ratio for highest versus lowest quartile: 0.20 (0.06-0.69)]. Triglycerides were also associated with deep or infratentorial microbleeds [odds ratio for highest versus lowest quartile: 0.37 (0.14-0.96)], but not with strictly lobar microbleeds. No associations were found for HDL-cholesterol or LDL-cholesterol. Low serum triglyceride levels were associated with an increased risk of intracerebral hemorrhage and with the presence of deep or infratentorial cerebral microbleeds. This provides novel insights into the role of lipid fractions, particularly triglycerides, in the etiology of intracerebral hemorrhage.

Brain MRI findings in patients with Fabry disease

Background To evaluate the presence of ischemic and hemorraghic lesions in brain MRI of patients with Fabry disease (FD). Methods Brain MRI studies in 46 consecutive patients were evaluated using classic sequences as well as GRE-weighted images, for ischemic lesions and chronic microbleed detection. Of the 36 adult patients (15 males, mean age 31.2 years; 21 females, mean age 41.6 years). All had signs or symptoms of FD but lacked history of stroke or TIA. Results Ten patients under 20 years of age initially presented a normal MRI. One child developed a hyperintense occipital lesion on T2-weighted imaging during control MRI. Sixteen adult patients (44.4%) had brain MRI evidence of small vessel disease in the basal ganglia, corona radiata, thalamus or brainstem, as well as in the periventricular white matter. Patients with MRI abnormalities were older (45.6 vs 30.9 years, p = 0.005), with more vascular risk factors (1.2 vs 0.6 p = 0.043). Three women (mean age 59.5 years) presented deep chronic microbleeds identified by GRE. Moreover, Flair and T2-weighted images revealed white matter disease and deep gray matter involvement. Conclusion 44.4% of adult patients with FD without clinical history of CVA or prior dialysis had evidence of small vessel disease on MRI and 11% showed cerebral microbleeds. FD is a treatable disorder that should be routinely included in the differential diagnosis of ischemic and microhemorraghic lesions in young adults.

Incidence of Cerebral Microbleeds in the General Population

Cerebral microbleeds are frequently seen in the general elderly population, but it is unknown at what rate they occur with aging and whether once present can disappear over time. As part of the Rotterdam Scan Study, 831 persons (mean age, 68.5 years) underwent repeated brain MRI with a mean interval of 3.4 years. We assessed determinants of incident microbleeds in relation to their location with multiple logistic regressions. Overall prevalence of microbleeds increased from 24.4% at baseline to 28.0% at follow-up. Eighty-five persons (10.2%) developed new microbleeds. Microbleeds at baseline predicted development of new microbleeds (OR, 5.38; 95% CI, 3.34 to 8.67). In only 6 persons with microbleeds at baseline, fewer microbleeds were present at the follow-up examination. Cardiovascular risk factors, presence of lacunar infarcts, and larger white matter lesion volume at baseline were all associated with incident deep or infratentorial microbleeds, whereas people with the apolipoprotein E ε4/ε4 genotype or larger white matter lesion volume had a higher risk of incident strictly lobar microbleeds. Incidence of microbleeds in the general population over a 3-year interval was substantial and microbleeds rarely disappeared. Risk factors for incident microbleeds were similar to those for prevalent microbleeds and differed according to microbleed location. These results support the assessment of microbleeds on T2-weighted MRI as a possible marker of both cerebral amyloid angiopathy and hypertensive vasculopathy progression.

Microbleeds and the Risk of Recurrent Stroke

We studied the risk of recurrent cerebrovascular events in patients who had a transient ischemic attack or ischemic stroke and who had evidence of microbleeds on MRI. A prospective follow-up study was performed on hospitalized patients who were at least 50 years old with a transient ischemic attack or an ischemic stroke. The presence and number of microbleeds were assessed on gradient echo MRI and the presence of white matter disease on fluid-attenuated inversion recovery imaging using a semiquantitative scale. Patients were followed up by phone every 6 months. End points were intracerebral hemorrhage, ischemic stroke, and unclassified stroke. Cerebral events were adjudicated by 2 independent neurologists blinded to the presence of microbleeds. Cox regression analysis was performed. A total of 487 patients with a mean age of 72 years were followed up for a median of 2.2 years (25th to 75th percentile 1.9 to 2.7 years). Microbleeds were identified in 129 patients (25.6%). Two patients developed intracerebral hemorrhage during follow-up, 32 patients developed recurrent ischemic stroke, and 3 patients had unclassified strokes. Microbleeds were not independent predictors of recurrent stroke (P=0.2) or intracerebral hemorrhage (P=0.43). Lobar microbleeds or combined lobar and deep microbleeds were independently associated with recurrent stroke (P=0.018). In this European cohort, patients with microbleeds who have had cerebral ischemia have a higher risk of developing new ischemic strokes than of intracerebral hemorrhage. Lobar microbleeds or combined lobar and deep microbleeds might be independent predictors of recurrent stroke.

Causes of Rectal Haemorrhage

Objective: Cerebral microbleeds are frequently found in the general elderly population and may reflect underlying vascular disease, but their role in cognitive function is unknown. Methods: We investigated the association between cerebral microbleeds and performance in multiple cognitive domains in 3,979 persons without dementia (mean age, 60.3 years). Mini-Mental State Examination (MMSE) score and neuropsychological tests were used to assess global cognition and the following cognitive domains: memory, information processing speed, executive function, and motor speed. We used number of microbleeds as continuous variable, and additionally distinguished between persons with no microbleeds, 1 microbleed, 2–4 microbleeds, and ≥5 microbleeds. The association of microbleeds with different cognitive domains was estimated using linear regression models. Additional adjustments were made for vascular risk factors, brain atrophy, and other imaging markers of cerebral small vessel disease. We stratified analyses by location of microbleeds. Results: A higher number of microbleeds was associated with lower MMSE score and worse performance on tests of information processing speed and motor speed. When analyzed per category, presence of 5 or more microbleeds was associated with worse performance in all cognitive domains, except memory. These associations were most robust in participants with strictly lobar microbleeds, whereas after additional adjustments associations disappeared for deep or infratentorial microbleeds. Conclusions: Presence of numerous microbleeds, especially in a strictly lobar location, is associated with worse performance on tests measuring cognitive function, even after adjustments for vascular risk factors and other imaging markers of small vessel disease. These results suggest an independent role for microbleed-associated vasculopathy in cognitive impairment.