A border associated macrophage that is adjacent to a small blood vessel of a brain. A perivascular macrophage expresses the markers CD14, CD16 and CD163. In homeostatic conditions, this central nervous system macrophage has a non-motile cell body with extending and retracting projections through the blood vessel wall. [ GOC:tfm http://purl.obolibrary.org/obo/go/references/0000031 http://www.ncbi.nlm.nih.gov/pubmed/16507898 http://www.ncbi.nlm.nih.gov/pubmed/37232741 ]