Shades of White

See related article, p 1721.In the play Art by Yasmina Reza, the main character puts his friendship with 2 others at risk when he purchases a piece of modern art that consists of a large white canvas with barely visible fine diagonal white lines.1 One of his friends attempts to explain the work to the unconvinced third.“Imagine a canvas about five foot by four…with a white background…completely white in fact…with fine white diagonal stripes…”“If the background’s white, how can you see the lines?” his friend asks.“You just do.…or anyway there are degrees of white! There’s more than one kind of white!” he responds, exasperated.In this issue of Stroke , Maillard et al2 quantitatively define the different types of white in the aging brain by examining fluid attenuation inversion recovery (FLAIR) intensity maps and fractional anisotropy (FA) in regions of white matter hyperintensites (WMH) and surrounding tissue. This work nicely elaborates and extends early work on diffusion changes in normal-appearing white matter in genetic small vessel disease3 and previous work from this group in mild cognitive impairment and Alzheimer disease.4,5WMH are frequently noted on FLAIR sequences in elderly patients. The prevalence of WMH increases with age6 and is associated with known vascular risk factors.7,8 The extent of WMH has been linked to cognitive impairment8,9 and to the risk of incident dementia.10 Progression of WMH has …