Fig. 7

Quantitative analyses of the density of string vessels and of the overall vessel density in the frontoparietal white matter. a The density of all types of string vessels as well as the density of string vessel tubes (S2 type) and string vessel ghosts (S4 type) is significantly increased in all SVD cases (pure SVD and SVD + VBI) when compared to NoSVD controls, whereas the density of collapsed/constricted string vessels (S3 type) is not affected (see Fig. 6 for morphology of S2 to S4 type string vessels quantified). b In contrast, the overall density of frontoparietal small vessels is not altered when all SVD cases are compared to NoSVD controls (left) or if a more detailed analysis is performed, in which DWMLs are compared to in-case control areas in the two SVD groups or to control areas in NoSVD cases (right). The “pure” SVD cases were referred to as SVD in the diagrams. * p < 0.05, ** p < 0.01, *** p < 0.001, n.s. not significant