The goal of this prospective, observational study is to understand if cerebral small vessel disease (CSVD) has different velocities and patterns of temporal development, dependent on a concurrent ischemic stroke. It focusses on adult patients with known or newly diagnosed CSVD on magnetic resonance imaging. The study will evaluate if blood based, in parts central nervous system specific protein markers, so called biomarkers, have an additional value reflecting the course of CSVD as defined per MRI assessments. Further patient-relevant endpoints include neuropsychological abilities, neurological functional outcomes, quality of life assessments, stroke recurrence risk.