Reader Response: Detection of Cerebral Microbleeds With Venous Connection at 7-Tesla MRI.

Abstract

Rotta et al.1 performed a 7T MRI study and found that approximately 14% of microbleeds (MBs) were related to a venous source using a Quantitative Susceptibility Mapping (QSM) sequence, challenging the artery origin of MBs.2 We support the notion that a certain number of MBs are closely connected to veins, which can also be visualized with 3T MRI Susceptibility Weighted Imaging (SWI) or QSM techniques. Indeed, the microbleed connection with veins may be more prevalent in the cortex.1 However, one should be aware that MBs in the cortex are more difficult to differentiate from the vessels than those deep and infratentorial MBs, especially in individuals with mild MBs burden.3,4 In this study,1 the control group had a low microbleed burden, whereas 25 of 31 healthy controls had at least 1 MB present (81%), which was higher than the prevalence reported from community studies (15%). It is possible that some vascular structures were misjudged as MBs in some patients.