Exploring the etiology in spontaneous intracerebral hemorrhage

Intracerebral hemorrhage (ICH) is the most deadly stroke subtype with two out of five patients dying within one month and a high morbidity in those surviving the ICH. Spontaneous ICH is non-traumatic hemorrhage caused by rupture of a small artery into the brain parenchyma and not the result of a secondary cause such as a vascular malformation, coagulation disorder or tumor. One of the factors hampering progress in prevention and treatment of ICH, is that the etiology of ICH is incompletely understood. In this thesis I further explored the etiology in spontaneous ICH. I have shown that in the last decades incidence, case fatality and mortality of ICH in the Netherlands vary in different age groups and sexes and that risk factor profiles are different for ICH in lobar and non-lobar locations. My findings make clear that we should stop regarding and treating ICH as one single disease. Cerebral microinfarcts (CMIs) and contrast leakage as marker of blood-brain barrier (BBB) disruption, found on MRI, may be novel markers of the small vessel disease (SVD) underlying ICH. I found CMIs on 7 tesla MRI in around two-thirds of our cohort of patients with lobar and non-lobar ICH and showed an association with cerebral microbleeds (CMBs), but not with other markers of SVD. BBB disruption was present in 54% of patients with lobar and non-lobar ICH and associated with presence and number of lobar CMBs. The question remains if CMIs and BBB disruption are a cause or the consequence of ICH.