title: Comparative study of the retinal vessel anatomy of rhesus monkeys and humans.
abstract: OBJECTIVE
  This study aims to compare retinal vessel anatomy of normal rhesus monkeys and humans and to provide a basis from a structural perspective for the use of rhesus monkey as an experimental model in future studies of retinal vessels.
  
  
  METHODS
  The retinas of six normal rhesus monkey eyes and eight human eyecups following corneal transplantation were obtained and stained using adenosine diphosphatase methods. The distributions, orders, layers of the retinal vessels and the perifoveal vascular ring were compared.
  
  
  RESULTS
  With adenosine diphosphatase staining, distinct retinal vessels were fully discernable from the first order surrounding the optic disc to the fifth order. There were no statistically significant differences between rhesus monkeys and humans in the percentages of vessels surrounding the optic disc at the equator and the peripheral region. Vascular networks in both species were arranged in several layers around the optic disc, two anastomotic layers at the equator and one sparse layer peripherally. Capillaries at the macular area were quite dense and an intact perifoveal vascular ring was observed. No differences were observed between rhesus monkeys and humans in the percentage area of the vessels and the area, perimeter and diameter of the perifoveal vascular ring.
  
  
  CONCLUSIONS
  The distributions, orders, layers and the perifoveal vascular ring of the retinal vessels of rhesus monkey are quite similar to those of humans. The data suggest that from an anatomical perspective, the rhesus monkey is a good animal model for the study of human retinal vessels, particularly the macular capillaries.
authors.affiliation: Eye and ENT Hospital, Shanghai Medical College, Fudan University, Shanghai, China.
authors.forename: Xiangmei
authors.initials: X
authors.lastname: Kong
authors.forename: Kaidi
authors.initials: K
authors.lastname: Wang
authors.forename: Xinghuai
authors.initials: X
authors.lastname: Sun
authors.forename: Rachel E
authors.initials: RE
authors.lastname: Witt
mesh_terms: D000818:Animals; D001081:Apyrase / Q000378:metabolism; D002196:Capillaries; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted; D007124:Immunoenzyme Techniques; D008253:Macaca mulatta; D008297:Male; D009898:Optic Disk / Q000098:blood supply; D011446:Prospective Studies; D012161:Retinal Artery / Q000033:anatomy & histology* / Q000201:enzymology; D012169:Retinal Vein / Q000033:anatomy & histology* / Q000201:enzymology
chemical_list: D001081:Apyrase