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Previous studies showed that various types of cerebral lesions, as assessed on MRI, largely contribute to the clinical severity of CADASIL. However, the clinical impact of longitudinal changes of classical markers of small vessel disease on conventional MRI has been only poorly investigated. One hundred sixty NOTCH3 mutation carriers (mean age ± SD, 49.8 ± 10.9 years) were followed over three years. Validated methods were used to determine the percent brain volume change (PBVC), number of incident lacunes, change of volume of white matter hyperintensities and change of number of cerebral microbleeds. Multivariable logistic regression analyses were performed to assess the independent association between changes of these MRI markers and incident clinical events. Mixed-effect multiple linear regression analyses were used to assess their association with changes of clinical scales. Over a mean period of 3.1 ± 0.2 years, incident lacunes are found independently associated with incident stroke and change of Trail Making Test Part B. PBVC is independently associated with all incident events and clinical scale changes except the modified Rankin Scale at three years. Our results suggest that, on conventional MRI, PBVC and the number of incident lacunes are the most sensitive and independent correlates of clinical worsening over three years in CADASIL.

Background and Purpose: The extent of white matter hyperintensities (WMH) is associated with cerebral atrophy in elderly people. WMH is a radiological hallmark of cerebral autosomal-dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL), but their relationship with brain volume remains poorly understood. The association between WMH and brain volume was analyzed in a large population of patients with CADASIL., Methods: Demographic and MRI data of 278 patients recruited from a prospective cohort study were analyzed. Volumes of WMH and lacunar infarcts, number of cerebral microbleeds, and brain parenchymal fraction were measured. Multivariate analysis was used to study the impact of WMH on brain volume at baseline., Results: In univariate analyses, brain parenchymal fraction was negatively associated with age, male sex, and all MRI markers. Multiple regression modeling showed that brain parenchymal fraction was inversely related to age, number of cerebral microbleeds, and normalized volume of lacunar infarcts but positively related to normalized volume of WMH (P<0.001). This positive relationship was independent of the presence/absence of lacunar infarcts or of cerebral microbleeds. Subgroup analysis showed that this association was significant in subjects having normalized volume of WMH ≥6.13 or brain parenchymal fraction ≥86.37% (median values, both P≤0.001)., Conclusions: The results of the present study suggest that extensive WMH may be associated with increase of brain volume in CADASIL. In this disorder, WMH may be related not only to loss of white matter components, but also to a global increase of water content in the cerebral tissue.

Background: Complaints about memory are common in older people but their relationship with underlying brain changes is controversial., Aims: To investigate the relationship between subjective memory impairment and previous or subsequent changes in white matter lesions and brain volumes., Method: In a community cohort study of 1336 people without dementia, 4-year changes in brain magnetic resonance imaging measures were investigated as correlates of subjective memory impairment at baseline and follow-up., Results: Subjective memory impairment at baseline was associated with subsequent change in hippocampal volume and at follow-up impairment was associated with previous change in hippocampal, cerebrospinal fluid and grey matter volume and with subcortical white matter lesion increases. All associations with volume changes were U-shaped with significant quadratic terms - associations between least decline and subjective memory impairment were potentially explained by lower baseline hippocampal volumes in the groups with least volume change. Associations between hippocampal volume change and subjective memory impairment at follow-up were independent of cognitive decline and depressive symptoms, they were stronger in participants with the apolipoprotein E (APOE) ε4 allele and in those without baseline subjective memory impairment., Conclusions: Complaints of poor memory by older people, particularly when new, may be a realistic subjective appraisal of recent brain changes independent of observed cognitive decline.

Several brain magnetic resonance imaging (MRI) changes are observed in older individuals including white matter lesions (WML), silent brain infarcts (SBI), and cerebral atrophy. Few studies, however, have assessed the combined association of these changes on the severity of future cognitive decline. In the prospective population-based 3C-Dijon MRI study, 1701 non-demented participants aged 65 to 80 years at entry had a brain MRI. Information on WML, hippocampal volumes, SBI presence, and brain parenchymal fraction were obtained. At 4-year follow-up, participants were screened for cognitive decline and dementia. Severity of cognitive decline was defined as none, moderate, or severe calculated from neuropsychological test performance change. The relation between brain MRI markers and longitudinal change in cognition was studied using polytomous logistic regression and multiple linear regression models controlling for potential confounders. Two-by-two interactions were tested including with the apolipoprotein E genotype. At follow-up, 46 participants showed severe cognitive deterioration and 224 participants showed moderate cognitive deterioration. In multivariable analyses, risk of severe cognitive deterioration as well as the cognitive decline rate were significantly increased in participants with higher WML volume (p< 0.01) and smaller hippocampal volume (p< 0.01). The results suggested that WML and hippocampal volumes had a cumulative effect on the future level of cognitive decline. The APOE genotype was found to be an effect modifier of this association. Vascular brain changes and degenerative processes coexist in normal older individuals. The co-occurrence of degenerative and non-degenerative pathologies could strongly affect the course of dementia expression.

Background: Brain atrophy and white-matter lesions (WML) are common features at cerebral MRI of both normal and demented elderly people. In a population-based study of 1,792 elderly subjects aged 65-80 years, free of dementia, who had a cerebral MRI at entry, we investigated the relationship between WML volume and brain atrophy markers estimated by hippocampal, gray matter (GM) and cerebrospinal fluid (CSF) volumes., Methods: An automated algorithm of detection and quantification of WML was developed, and voxel-based morphometry methods were used to estimate GM, CSF and hippocampal volumes. To evaluate the relation between those volumes and WML load, we used analysis of covariance and multiple linear regression models adjusting for potential confounders and total intracranial volumes., Results: Age was highly correlated with WML load and all brain atrophy markers. Total WML volume was negatively associated with both GM (beta = -0.03, p < 0.0001) and hippocampal volumes (beta = -0.75, p = 0.0009) and positively with CSF volumes (beta = 0.008, p = 0.02) after controlling for sex, age, education level, hypertension and apolipoprotein E genotype. Evidence for a relationship between brain atrophy markers and WML was stronger for periventricular WML. We found that the relationship between WML and hippocampal volumes was independent of other brain tissue volumes., Conclusion: These results suggest that, in the brain of nondemented elderly subjects, degenerative processes and vascular changes co-occur and are related independently of vascular risk factors., (2009 S. Karger AG, Basel.)

Background and Purpose: Three-dimensional MRI segmentation may be useful to better understand the physiopathology of lacunar infarctions. Using this technique, the distribution of lacunar infarctions volumes has been recently reported in patients with cerebral autosomal-dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL). Whether the volume of each lacune (individual lacunar volume [ILV]) is associated with the patients' other MRI lesions or vascular risk factors has never been investigated. The purpose of this study was to study the impact of age, vascular risk factors, and MRI markers on the ILV in a large cohort of patients with CADASIL., Methods: Of 113 patients with CADASIL, 1568 lacunes were detected and ILV was estimated after automatic segmentation on 3-dimensional T1-weighted imaging. Relationships between ILV and age, blood pressure, cholesterol, diabetes, white matter hyperintensities load, number of cerebral microbleeds, apparent diffusion coefficient, brain parenchymal fraction, and mean and median of distribution of lacunes volumes at the patient level were investigated. We used random effect models to take into account intraindividual correlations., Results: The ILV varied from 4.28 to 1619 mm(3). ILV was not significantly correlated with age, vascular risk factors, or different MRI markers (white matter hyperintensity volume, cerebral microbleed number, mean apparent diffusion coefficient or brain parenchymal fraction). In contrast, ILV was positively correlated with the patients' mean and median of lacunar volume distribution (P=0.0001)., Conclusions: These results suggest that the ILV is not related to the associated cerebral lesions or to vascular risk factors in CADASIL, but that an individual predisposition may explain predominating small or predominating large lacunes among patients. Local anatomic factors or genetic factors may be involved in these variations.

We compared the severity of white matter T2-hyperintensities (WMH) in the frontal lobe and occipital lobe using a visual MRI score in 102 patients with lobar intracerebral hemorrhage (ICH) diagnosed with possible or probable cerebral amyloid angiopathy (CAA), 99 patients with hypertension-related deep ICH, and 159 normal elderly subjects from a population-based cohort. The frontal-occipital (FO) gradient was used to describe the difference in the severity of WMH between the frontal lobe and occipital lobe. A higher proportion of subjects with obvious occipital dominant WMH (FO gradient ≤−2) was found among patients with lobar ICH than among healthy elderly subjects (FO gradient ≤−2: 13.7 vs. 5.7%, p = 0.03). Subjects with obvious occipital dominant WMH were more likely to have more WMH ( p = 0.0006) and a significantly higher prevalence of the apolipoprotein E ε4 allele (45.8% vs. 19.4%, p = 0.04) than those who had obvious frontal dominant WMH. This finding is consistent with the relative predilection of CAA for posterior brain regions, and suggests that white matter lesions may preferentially occur in areas of greatest vascular pathology. [ABSTRACT FROM AUTHOR]