Fig. 2
From: Dilated perivascular spaces and steno-occlusive changes in children and adults with moyamoya disease
Representative example of dilated perivascular spaces (DPVS) and MRA grade in 5-year-old male without any vascular risk factors. (a) Less than 5 DPVS (arrowheads, degree of 1) are observed in both basal ganglia. (b) More than 40 DPVS (arrowheads, degree of 4) are observed in the right white matter, and less than 40 DPVS (arrowheads, degree of 3) is observed in the left white matter: it can be defined as asymmetry between the DPVS degrees of both sides. (c) The right side have the MRA score of 5 (ICA, 2 + MCA, 2 + ACA, 1 + PCA, 0) and the MRA grade of 3. The left side have the MRA score of 4 (ICA, 1 + MCA, 1 + ACA, 1 + PCA, 0) and the MRA grade of 2. Therefore, it can be defined that both MRA grades are asymmetric with each other