Retinochoroidal collateral veins protect against anterior segment neovascularization after central retinal vein occlusion.
OBJECTIVE
To test the hypothesis that retinochoroidal collateral veins (RCVs), or alternatively, retinociliary or optociliary shunts/collaterals/veins or opticociliary anastomoses, act protectively against the development of anterior segment neovascularization (ASN) following central retinal vein occlusion (CRVO).


METHODS
Case-control retrospective medical record review of patients with CRVO.


METHODS
We identified 107 patients with CRVO, of whom 34 had developed ASN, by reviewing their medical records. After applying exclusion criteria, a case group and an age-, sex-, and visual acuity-matched control group were selected. We analyzed these groups for the presence or absence of RCVs and noted the time course involved in their development.


METHODS
Anterior segment neovascularization (including neovascularization of the iris and/or anterior chamber angle), neovascular glaucoma, and RCV development.


RESULTS
Only 1 (5.4%) of 19 individuals who developed ASN did so in the presence of RCVs. In contrast, 11 (57.9%) of 19 individuals in the control group developed RCVs. Statistical analysis revealed that patients who developed ASN were roughly 25 times less likely to have had RCVs than individuals who never developed ASN (odds ratio = 24.74; P =.001).


CONCLUSIONS
Retinochoroidal collateral veins are negatively associated with ASN post-CRVO and may function in a protective manner against such an outcome.
Fuller
Jeffrey J
JJ
Medical College of Georgia, Augusta, USA. retinaconsultant@mindspring.com
Mason
John O
JO
White
Milton F
MF
McGwin
Gerald
G
Emond
Tracy L
TL
Feist
Richard M
RM
D000368:Aged; D000369:Aged, 80 and over; D000869:Anterior Eye Segment / Q000098:blood supply*; D002829:Choroid / Q000098:blood supply*; D003097:Collateral Circulation; D005260:Female; D005451:Fluorescein Angiography; D015355:Glaucoma, Neovascular / Q000209:etiology / Q000517:prevention & control; D006801:Humans; D007498:Iris / Q000098:blood supply*; D008297:Male; D008875:Middle Aged; D009389:Neovascularization, Pathologic / Q000209:etiology / Q000517:prevention & control*; D009898:Optic Disk / Q000098:blood supply; D012170:Retinal Vein Occlusion / Q000150:complications / Q000503:physiopathology*; D012171:Retinal Vessels / Q000502:physiology*; D012189:Retrospective Studies; D014680:Veins