Cerebrospinal fluid may nourish cerebral vessels through pathways in the adventitia that may be analogous to systemic vasa vasorum

Abstract
✓ Cerebral blood vessels are devoid of vasa vasorum. Therefore, the authors have studied the microarchitecture of the adventitia of large feline cerebral vessels and systemic vessels of the same size, in an effort to determine how the vessels are nourished. The cerebral vessels contain a rete vasorum in the adventitia that is permeable to large proteins and is in continuity with the subarachnoid space. This substructure may be analogous to the systemic vasa vasorum and may contribute to the nutrition of the cerebral arteries.