CADASIL: yesterday, today, tomorrow.

BACKGROUND AND PURPOSE: In 2019, the Brain Prize crowned the discovery of CADASIL in the 1990s and research efforts on this archetypal small vessel disease of the brain over 40 years. METHODS AND RESULTS: The hereditary origin of this arteriolopathy was discovered from a first clinical case and detailed observation of the patient's family. Thereafter, the role of causative mutations within the NOTCH3 gene were identified, allowing the development of a genetic test and then of an animal model of the disease. These crucial steps led to the discovery progressively that CADASIL is the most common genetic cerebral small vessel disease, to describing for the first time the natural history of a cerebral ischaemic small vessel disease from silent cerebral tissue lesions up to severe motor disability and dementia at the end stage, to demonstrating the central role of matrix proteins in its pathophysiology and to opening the door to the discovery of several other genes involved in monogenic cerebral small vessel diseases. DISCUSSION: Today, CADASIL is known to every neurologist, but the disease has not yet revealed all its secrets. A lot of effort is still needed to understand the intimate mechanisms of the disease and the most efficient targets or approaches for the development of efficient therapeutics. The history of CADASIL will be further enriched by multiple ongoing research projects worldwide, at clinical and preclinical level, and will continue to enlighten research in the field of cerebral small vessel disorders.

Monogenic cerebral small-vessel diseases: diagnosis and therapy. Consensus recommendations of the European Academy of Neurology.

BACKGROUND AND PURPOSE: Guidelines on monogenic cerebral small-vessel disease (cSVD) diagnosis and management are lacking. Endorsed by the Stroke and Neurogenetics Panels of the European Academy of Neurology, a group of experts has provided recommendations on selected monogenic cSVDs, i.e. cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL), cerebral autosomal recessive arteriopathy with subcortical infarcts and leukoencephalopathy (CARASIL), autosomal dominant High Temperature Requirement A Serine Peptidase 1 (HTRA1), cathepsin-A-related arteriopathy with strokes and leukoencephalopathy (CARASAL), pontine autosomal dominant microangiopathy and leukoencephalopathy (PADMAL), Fabry disease, mitochondrial encephalopathy, lactic acidosis and stroke-like episodes (MELAS) and type IV collagen (COL4)A1/2. METHODS: We followed the Delphi methodology to provide recommendations on several unanswered questions related to monogenic cSVD, including genetic testing, clinical and neuroradiological diagnosis, and management. RESULTS: We have proposed 'red-flag' features suggestive of a monogenic disease. General principles applying to the management of all cSVDs and specific recommendations for the individual forms of monogenic cSVD were agreed by consensus. CONCLUSIONS: The results provide a framework for clinicians involved in the diagnosis and management of monogenic cSVD. Further multicentre observational and treatment studies are still needed to increase the level of evidence supporting our recommendations.

Imaging of the aging brain and development of MRI signal abnormalities.

Major changes occur at the cerebral level with aging. Cerebral atrophy develops progressively. Multiple lesions related to small-vessel diseases are detected in association with cerebral atrophy including white-matter hyperintensities, lacunes, microbleeds, dilated perivascular spaces and cerebral, including cortex, atrophy. The clinical impact and predictive value of these Imaging makers were examined.

Clinical features related to CSF level of amyloid Aß42 and Aß40 proteins in presence of lobar microbleeds.

In presence of lobar microbleeds, the exact clinical features related to the level of Aß42, Aß40 and to the Aß40/Aß42 ratio in the cerebrospinal fluid (CSF) are poorly known. We analyzed in 28 consecutive patients with such lesions, whose clinical or additional magnetic resonance imaging features are related to these biomarkers. The results showed that the presence of absence of hypertension, the extent or the antero-posterior distribution of white matter hyperintensities, the presence or absence of vascular lesions in the deepest parts of the brain, and the presence of dementia are related to variations of Aß42, Aß40 or of the Aß40/Aß42 ratio in the cerebrospinal fluid.

Leukoencephalopathy with calcifications and cysts (LCC): 5 cases and literature review.

INTRODUCTION: Leukoencephalopathy with calcifications and cysts (LCC) is a rare autosomal recessive cerebral angiomatous-like microangiopathy characterized by diffuse and asymmetric white-matter lesions associated with multiple calcifications and cysts. The disease is caused by SNORD118 mutations. The entire clinical spectrum of LCC is not yet fully determined. MATERIAL AND METHODS: To define the clinical spectrum of LCC, we analyzed data from recently diagnosed cases and from the litterature. Both clinical and imaging features from our five LCC cases harboring compound heterozygous SNORD118 mutations were presented and all cases reported in the litterature reviewed. RESULTS: Ninety-two LCC cases including our five patients were identified. Consanguinity was rare (4%), and 97% of cases were symptomatic. Mean age of first clinical manifestations was 16.1±16.1 years (range 1 month-71 years) and was earlier in men (10.3±14.3 years) than in women (20.2±22.8 years) (P=0.02). The main inaugural symptoms were seizures (36%; mean age at onset: 5.2±9.5 years) and progressive neurological symptoms including ataxia, dystonia and spasticity (26%; 27.8±23.6 years). Intracranial hypertension was less frequently observed (14%), mostly in adults (mean age 31.5±13.2 years). Ischemic or hemorrhagic strokes were inaugural symptoms in two adults (2%). During follow-up, most patients developed progressive extrapyramidal, cerebellar and pyramidal signs (83%), cognitive decline (56%), seizures (37%), intracranial hypertension (30%) or stroke (2%). CONCLUSION: In LCC, the clinical spectrum is largely heterogeneous and the course of the disease appears highly variable in contrast to other hereditary cerebral small vessel diseases.

Can anticoagulation therapy in cerebral venous thrombosis associated with Behçet's disease be stopped without relapse?

There is as yet no consensus on the treatment of cerebral venous thrombosis (CVT) in Behçet's disease, and the place of anticoagulation is also still being debated. This report is of a series of seven patients with Behçet's disease (BD)-associated CVT, for which anticoagulation was stopped, and discusses the possibility of stopping anticoagulation during follow-up while receiving optimal treatment for BD. The diagnosis of BD was established during follow-up, which lasted a median of 120 [range: 60-1490] days after CVT diagnosis. The median duration of anticoagulation therapy was 29.5 months. On stopping anticoagulation, concomitant treatment then included colchicine, steroids and azathioprine, all introduced after BD was diagnosed. With a median follow-up of 25 months after anticoagulation interruption, only one relapse of CVT was observed. No relapse of CVT or other venous thrombosis was observed in the six patients treated by steroids associated with an immunosuppressant or colchicine. Our results emphasize that corticosteroids are essential for the treatment of BD-associated CVT, and that anticoagulant therapy may be safely stopped during follow-up in the presence of optimal BD treatment (steroids alone or with immunosuppressive drugs).

Diffusion magnetic resonance imaging in cerebral small vessel disease.

Cerebral small vessel disease (SVD) is frequent in the elderly, and accounts for a wide spectrum of clinical and radiological manifestations. This report summarizes the most important findings obtained using diffusion MRI (DWI) in SVD. With DWI and apparent diffusion coefficient (ADC) maps, recent ischemic lesions can easily be detected after acute stroke in SVD, while even multiple simultaneous lesions may be observed. Microstructural changes are frequent in SVD, with increases in diffusivity and decreases in anisotropy being the most reliable findings observed, mainly in white matter. These tissue changes are associated with clinical severity and especially executive dysfunction. They can also precede the usual MRI markers of SVD, such as white matter hyperintensities, microbleeds and lacunes. Thus, DWI may reveal surrogate markers of SVD progression and offer a better understanding of their underlying mechanisms.

Microvascular retinal abnormalities in acute intracerebral haemorrhage and lacunar infarction.

BACKGROUND: Retinal microvascular changes have been previously associated with cerebral MRI markers of small vessel disease (SVD). Whether retinal changes differ between patient with intracerebral haemorrhage (ICH) and patients with lacunar infarction (LI) caused by small vessel disease has been poorly investigated. OBJECTIVE: The study aims to compare the frequency of retinal changes between patients with LI and patients with ICH at the acute stage of stroke-related SVD. METHODS: Microvascular wall signs (arteriolar occlusion, arteriovenous nicking, focal arterial narrowing) and retinopathy lesions (microanevrysms, cotton wool spots, retinal haemorrhages, hard exudates) were assessed by retinography up to three months after stroke onset. RESULTS: Forty-eight non-diabetic patients with acute stroke-related to SVD (26 LI, 22 ICH) were recruited prospectively in the study. Retinal wall signs (arteriovenous nicking, and focal arterial narrowing) were found in more than three quarters of subjects and most often bilaterally in both groups. Retinopathy lesions (cotton wool spots, retinal haemorrhages) were found more frequently in ICH patients than in LI patients (22.2% vs. 15.4%, 50% vs. 34% respectively, P>0.005). The frequency of bilateral cotton wool spots and of bilateral retinal haemorrhages was significantly higher in ICH patients than in LI patients (12.5% vs. 0%, P=0.012, 41.2% vs. 7.7%, P=0.029 respectively). CONCLUSION: These results confirm the high frequency of microvascular alterations in patients with hypertension-related SVD leading to LI or ICH and suggest that retinal tissue alterations are more frequent in ICH than in LI. Further investigations are needed to investigate the mechanisms underlying this difference.

Characterization of Retinal Arteries by Adaptive Optics Ophthalmoscopy Image Analysis.

OBJECTIVE: This paper aims at quantifying biomarkers from the segmentation of retinal arteries in adaptive optics ophthalmoscopy images (AOO). METHODS: The segmentation is based on the combination of deep learning and knowledge-driven deformable models to achieve a precise segmentation of the vessel walls, with a specific attention to bifurcations. Biomarkers (junction coefficient, branching coefficient, wall to lumen ratio ( wlr)) are derived from the resulting segmentation. RESULTS: reliable and accurate segmentations ( mse = 1.75 ±1.24 pixel) and measurements are obtained, with high reproducibility with respect to images acquisition and users, and without bias. SIGNIFICANCE: In a preliminary clinical study of patients with a genetic small vessel disease, some of them with vascular risk factors, an increased wlr was found in comparison to a control population. CONCLUSION: The wlr estimated in AOO images with our method (AOV, Adaptive Optics Vessel analysis) seems to be a very robust biomarker as long as the wall is well contrasted.

Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy maps to chromosome 19q12.

Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) has been recently reported as a cause of stroke. It is characterized, in the absence of hypertension, by recurrent subcortical ischaemic strokes, starting in early or midadulthood and leading in some patients to dementia. Magnetic resonance imaging and pathological examination show numerous small subcortical infarcts and a diffuse leukoencephalopathy underlaid by a non-arteriosclerotic, non-amyloid angiopathy. We performed genetic linkage analysis in two unrelated families and assigned the disease locus to chromosome 19q12. Multilocus analysis with the location scores method established the best estimate for the location of the affected gene within a 14 centimorgan interval bracketed by D19S221 and D19S222 loci.

A gene for familial hemiplegic migraine maps to chromosome 19.

Familial hemiplegic migraine is an autosomal dominant disorder of unknown pathogenesis in which the migrainous attacks are marked by the occurrence of a transient hemiplegia during the aura. While investigating CADASIL, mapped previously to chromosome 19, we observed that some patients had recurrent attacks of migraine with aura. Although the clinical and neuroimaging features of familial hemiplegic migraine differ markedly from CADASIL, we hypothesized that the same gene could be involved in the pathogenesis of both conditions. We chose two large pedigrees for linkage analysis of familial hemiplegic migraine. A maximum lod score > 8 was found with two markers that are also strongly linked to CADASIL. Multilocus linkage analysis suggested that the loci responsible for the two diseases reside within an interval of about 30 cM on chromosome 19.

[Reference center for rare vascular diseases of the eye and brain]. / CERVCO, Centre de référence des maladies vasculaires rares du cerveau et de l'oeil.

The reference center CERVCO (for rare diseases of the blood vessels in the brain and eye) is involved in the management of various rare vascular diseases of the brain and retina. Any progress made in recent years is variable and depends on the disease concerned. The reference center is also heavily involved in many of the research activities that have taken place over the past 5 years to improve the diagnosis and treatment of these diseases, but the challenges for the future are different for each of them. The reference center now needs simplified assessment tools, the formal recognition of a network of medical 'experts', and adaptation of its technical and human resources to achieve its objectives.

Psychological impact of COVID-19 containment on CADASIL patients.

INTRODUCTION: COVID-19 restrictive containment was responsible for major psychological distress and alteration of quality of life (QoL) in the general population. Their impact in a group of patients having cerebral small vessel disease (SVD) and at high risk of stroke and disability was unknown. OBJECTIVE: We aimed to determine the potential psychological impact of strict containment during the COVID-19 pandemic in a sample of CADASIL patients, a rare SVD caused by NOTCH3 gene mutations. METHODS: Interviews of 135 CADASIL patients were obtained just after the end of the strict containment in France. Depression, QoL and negative subjective experience of the containment were analysed, as well as predictors of posttraumatic and stressor-related manifestations, defined as an Impact Event Scale-Revised score ≥ 24, using multivariable logistic analysis. RESULTS: Only 9% of patients showed a depressive episode. A similar proportion had significant posttraumatic and stressor-related disorder manifestations independently associated only with socio-environment factors, rather than clinical ones: living alone outside a couple (OR 7.86 (1.87-38.32), unemployment (OR 4.73 (1.17-18.70)) and the presence of 2 or more children at home (OR 6.34 (1.35-38.34). CONCLUSION: Psychological impact of the containment was limited in CADASIL patients and did not appear related to the disease status. About 9% of patients presented with significant posttraumatic and stressor-related disorder manifestations which were predicted by living alone, unemployment, or exhaustion related to parental burden.

Paediatric moyamoya in mainland France: a comprehensive survey of academic neuropaediatric centres.

BACKGROUND: Epidemiological data of paediatric moyamoya disease/syndrome (MMD/MMS) in non-Asian populations are scarce. METHODS: A questionnaire was sent to every French neuropaediatric academic centre to estimate the prevalence, incidence, familial form rate and location of paediatric MMD/MMS cases. Specific paediatric data were also retrieved from the most recent nationwide Japanese study. RESULTS: A 100% response rate was obtained. The prevalence of paediatric MMD/MMS was estimated at 0.39/100,000 children (95% CI: 0.28-0.49), and the incidence was estimated at 0.065/100,000 children/year (95% CI: 0.025-0.12), with 7.5% familial cases. The prevalence was homogenous within the different administrative areas. CONCLUSIONS: This comprehensive survey of MMD/MMS in academic neuropaediatric centres suggests that the prevalence of the disease in children in France is approximately 1/20th of that estimated in Asia.

The Epidermal Growth Factor Domain of the Mutation Does Not Appear to Influence Disease Progression in CADASIL When Brain Volume and Sex Are Taken into Account.

BACKGROUND AND PURPOSE: By studying the evolution of brain volume across the life span in male and female patients, we aimed to understand how sex, brain volume, and the epidermal growth factor repeat domain of the mutation, the 3 major determinants of disability in CADASIL, interact in driving disease evolution. MATERIALS AND METHODS: We used validated methods to model the evolution of normalized brain volume with age in male and female patients using nonparametric regression in a large, monocentric cohort with prospectively collected clinical and high-resolution MR imaging data. We used k-means clustering to test for the presence of different clinical course profiles. RESULTS: We included 229 patients (mean age, 53 [SD, 12] years; 130 women). Brain volume was larger in women (mean size, 1024 [SD, 62] cm3 versus 979 [SD, 50] cm3; P < .001) and decreased regularly. In men, the relationship between brain volume and age unexpectedly suggested an increase in brain volume around midlife. Cluster analyses showed that this finding was related to the presence of a group of older male patients with milder symptoms and larger brain volumes, similar to findings of age-matched women. This group did not show specific epidermal growth factor repeat domain distribution. CONCLUSIONS: Our results demonstrate a detrimental effect of male sex on brain volume throughout life in CADASIL. We identified a subgroup of male patients whose brain volume and clinical outcomes were similar to those of age-matched women. They did not have a specific distribution of the epidermal growth factor repeat domain, suggesting that yet-unidentified predictors may interact with sex and brain volume in driving disease evolution.

Heritable and non-heritable uncommon causes of stroke.

Despite intensive investigations, about 30% of stroke cases remains of undetermined origin. After exclusion of common causes of stroke, there is a number of rare heritable and non-heritable conditions, which often remain misdiagnosed, that should be additionally considered in the diagnosis of cryptogenic stroke. The identification of these diseases requires a complex work up including detailed clinical evaluation for the detection of systemic symptoms and signs, an adequate neuroimaging assessment and a careful family history collection. The task becomes more complicated by phenotype heterogeneity since stroke could be the primary or unique manifestation of a syndrome or represent just a manifestation (sometimes minor) of a multisystem disorder. The aim of this review paper is to provide clinicians with an update on clinical and neuroradiological features and a set of practical suggestions for the diagnostic work up and management of these uncommon causes of stroke. The identification of these stroke causes is important to avoid inappropriate and expensive diagnostic tests, to establish appropriate management measures, including presymptomatic testing, genetic counseling, and, if available, therapy. Therefore, physicians should become familiar with these diseases to provide future risk assessment and family counseling.

Relationship between baseline white-matter changes and development of late-life depressive symptoms: 3-year results from the LADIS study.

BACKGROUND: Growing evidence suggests that cerebral white-matter changes and depressive symptoms are linked directly along the causal pathway. We investigated whether baseline severity of cerebral white-matter changes predict longer-term future depressive outcomes in a community sample of non-disabled older adults. METHOD: In the Leukoaraiosis and Disability in the Elderly (LADIS) study, a longitudinal multi-centre pan-European study, 639 older subjects underwent baseline structural magnetic resonance imaging (MRI) and clinical assessments. Baseline severity of white-matter changes was quantified volumetrically. Depressive outcomes were assessed in terms of depressive episodes and depressive symptoms, as measured by the Geriatric Depression Scale (GDS). Subjects were clinically reassessed annually for up to 3 years. Regression models were constructed to determine whether baseline severity of white-matter changes predicted future depressive outcomes, after controlling for confounding factors. RESULTS: Baseline severity of white-matter changes independently predicted depressive symptoms at both 2 (p<0.001) and 3 years (p=0.015). Similarly, white-matter changes predicted incident depression (p=0.02). Over the study period the population became significantly more disabled (p<0.001). When regression models were adjusted to account for the influence of the prospective variable transition to disability, baseline severity of white-matter changes no longer predicted depressive symptoms at 3 years (p=0.09) or incident depression (p=0.08). CONCLUSIONS: Our results support the vascular depression hypothesis and strongly implicate white-matter changes in the pathogenesis of late-life depression. Furthermore, the findings indicate that, over time, part of the relationship between white-matter changes and depression may be mediated by loss of functional activity.

CADASIL.

Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) is a dominantly inherited small artery disease that leads to dementia and disability in mid-life. The clinical presentation of CADASIL is variable between and within affected families and is characterized by symptoms including migraine with aura, subcortical ischemic events, mood disturbances, apathy, and cognitive impairment. The mean age at onset of symptoms is 45 years, with variable duration of the disease ranging from 10 to 40 years. In 1996, linkage studies mapped and identified mutations in the NOTCH3 gene on chromosome 19 as causative in CADASIL. Head magnetic resonance imaging (MRI) is always abnormal in participants with NOTCH3 mutations after age 35. Magnetic resonance imaging shows on T2-weighted images or fluid attenuation inversion recovery (FLAIR) sequence, widespread areas of increased signal in the white matter associated with focal hyperintensities in basal ganglia, thalamus, and brainstem. The pathologic hallmark of CADASIL is the presence of electron-dense granules in the media of arterioles that can be identified by electron microscopic evaluation of skin biopsies.

Vascular risk factors and morphometric data in cervical artery dissection: a case-control study.

BACKGROUND: Limited knowledge exists on vascular risk factors, body height and weight in patients with spontaneous cervical artery dissection (sCAD). PATIENTS AND METHODS: In this case-control study, major vascular risk factors, body weight, body height and body mass index (BMI) of 239 patients obtained from a prospective hospital-based sCAD registry were compared with 516 age- and sex-matched healthy controls undergoing systematic health examinations in the Clinical and Preventive Investigations Center, Paris. Gender-specific analyses were performed. RESULTS: The mean body height was higher in sCAD patients than in controls (171.3 cm (SD 8.6) vs 167.7 cm (8.9); p<0.0001) and sCAD patients had a significantly lower mean body weight (67.5 (12.2) kg vs 69.3 (14.6) kg; p<0.001) and mean BMI (22.9 (3.3) kg/m2 vs 24.5 (4.2) kg/m2; p<0.0001) than controls. The overall frequency of hypertension, diabetes, current smoking, past smoking and hypercholesterolaemia did not differ significantly between sCAD patients and controls. The mean total plasma cholesterol level was identical in both groups (5.5 mmol/l, SD 1.1). Gender specific subgroup analyses showed similar results for men and women. CONCLUSION: Patients with sCAD had a higher body height and a lower body weight and BMI than controls, while major vascular risk factors were similar in sCAD patients and controls.