Hereditary cerebral haemorrhage with amyloidosis--Dutch type. Magnetic resonance imaging findings in 7 cases. The clinical history and magnetic resonance imaging (MRI) findings are presented of 7 patients with hereditary cerebral haemorrhage with amyloidosis--Dutch type (HCHWA-D). The diagnosis was based on clinical and genealogical data, was confirmed in 3 patients at autopsy and in 2 others by biopsy. Focal neurological signs, and at least some degree of global cognitive deterioration, were observed in all patients, with unequivocal dementia in 4. MRI showed haemorrhages and areas of gliosis and, to a variable extent, hyperintensity of the white matter in T2-weighted images. Neuropathological examination revealed a large recent haemorrhage together with residual lesions from previous haemorrhages or infarcts in all patients examined. The white matter lesions, present on MRI, turned out to be areas of 'incomplete infarction' with demyelination. It is concluded that (hereditary) amyloid angiopathy can lead to strokes, but also to subcortical ischaemic encephalopathy. Amyloid angiopathy should therefore be considered in the differential diagnosis of white matter lesions, found on CT or MRI, especially when patients present with a cerebral haemorrhage. The relationship between HCHWA-D and Alzheimer's disease, another disease with cerebral amyloid deposition and diffuse white matter involvement, is discussed. 