Cerebral Small Vessel DiseasesLeukoaraiosisBrain InfarctionStroke, LacunarLeukoencephalopathiesDementia, VascularCerebrovascular DisordersMagnetic Resonance ImagingMicrovesselsBrainNerve Fibers, MyelinatedCADASILVenulesCognition DisordersStrokeCerebrovascular CirculationImage Processing, Computer-AssistedRisk FactorsProspective StudiesNetherlandsCerebral ArteriesDementia, Multi-InfarctCohort StudiesCerebral InfarctionBasal Ganglia Cerebrovascular DiseaseBrain Ischemia