In vivo retinal vascular oxygen tension imaging and fluorescein angiography in the mouse model of oxygen-induced retinopathy.
OBJECTIVE
Oxygenation abnormalities are implicated in the development of retinopathy of prematurity (ROP). The purpose of this study is to report in vivo retinal vascular oxygen tension (PO2) measurements and fluorescein angiography (FA) findings in the mouse model of oxygen-induced retinopathy (OIR).


METHODS
We exposed 19 neonatal mice to 77% oxygen from postnatal day 7 (P7) to P12 (OIR), while 11 neonatal mice were kept under room air (control). Using phosphorescence lifetime imaging, retinal vascular PO2 was measured followed by FA. Repeated measures ANOVA was performed to determine the effects of blood vessel type (artery and vein) and group (OIR and control) on PO2. Avascular retinal areas were measured from FA images in OIR mice.


RESULTS
There was a significant effect of vessel type on PO2 (P < 0.001). The effect of group on PO2 was not significant (P = 0.3), indicating similar PO2 between OIR and control mice. The interaction between group and vessel type was significant (P = 0.03), indicating a larger arteriovenous PO2 difference in OIR mice than control mice. In control mice, FA displayed normal vascularization, while FA of OIR mice showed abnormalities, including dilation and tortuosity of major retinal blood vessels, and avascular regions. In OIR mice, the mean percent avascular retinal area was 33% ± 18%.


CONCLUSIONS
In vivo assessment of retinal vascular oxygen tension and vascularization patterns demonstrated abnormalities in the mouse model of OIR. This approach has the potential to improve understanding of retinal vascular development and oxygenation alterations due to ROP and other ischemic retinal diseases.
Department of Pediatrics, University of Illinois at Chicago, Chicago, Illinois.
Olachi J
OJ
Mezu-Ndubuisi
Pang-yu
PY
Teng
Justin
J
Wanek
Norman P
NP
Blair
Felix Y
FY
Chau
Narsa M
NM
Reddy
J Usha
JU
Raj
Sekhar P
SP
Reddy
Mahnaz
M
Shahidi
D000704:Analysis of Variance; D000818:Animals; D004195:Disease Models, Animal; D005451:Fluorescein Angiography; D051379:Mice; D008810:Mice, Inbred C57BL; D010100:Oxygen / Q000378:metabolism* / Q000494:pharmacology; D012171:Retinal Vessels / Q000378:metabolism* / Q000473:pathology; D012178:Retinopathy of Prematurity / Q000378:metabolism* / Q000473:pathology
D010100:Oxygen
fluorescein angiography; oxygen-induced retinopathy; retina; retinopathy of prematurity; vascular oxygen tension