Olachi J Mezu-Ndubuisi1,2, Thao Adams3, Lauren K Taylor3, Adaure Nwaba4, Jens Eickhoff3. 1. Departments of Pediatrics, University of Wisconsin School of Medicine and Public Health, 600 Highland Avenue, Madison, WI, 53792, USA. olachimezu@pediatrics.wisc.edu. 2. Ophthalmology and Visual Sciences, University of Wisconsin School of Medicine and Public Health, 600 Highland Avenue, Madison, WI, 53792, USA. olachimezu@pediatrics.wisc.edu. 3. Departments of Pediatrics, University of Wisconsin School of Medicine and Public Health, 600 Highland Avenue, Madison, WI, 53792, USA. 4. Center for Biotechnology, Krieger School of Arts & Sciences, Johns Hopkins University, 3400N. Charles St, Baltimore, MD, 21218, USA.
Abstract
BACKGROUND: Retinopathy of prematurity is a condition of abnormal retinal vascularization in premature infants. The effect of abnormal vascularization on retinal structure and function is unclear. In vivo studies of retinal vascularization, thickness, and function were performed in mice with oxygen-induced retinopathy (OIR mice). METHODS: Eighteen mice were exposed to hyperoxia at postnatal day (P) 7, whereas 18 mice were raised in room air (RA). At P20 and 40, electroretinogram was performed for a-wave and b-wave amplitudes and peak times, followed by simultaneous fluorescein angiography for retinal avascular area, arterial tortuosity, and vein dilation assessments, and spectral domain optical coherence tomography for retinal thickness. RESULTS: Capillary density appeared sparser in OIR mice, but retinal avascular area similar to RA mice. Retinal artery tortuosity was higher at P20 and P40 (P = 0.0001) in OIR than RA mice. OIR mice had dilated retinal veins at P20 and thinner inner retinas at P40. Retinal vein width positively correlated with inner retinal thickness (P = 0.008). b-wave amplitude was decreased in avascular retinal areas, and correlated with inner retinal thinning. b-wave peak time was prolonged in adult OIR mice at high intensities (P = 0.03). CONCLUSIONS: Focal variations in retinal vascularization of OIR mice correlate with thickness and function. Adult OIR mice had increased retinal artery tortuosity, prolonged b-wave peak time, and decreased retinal vein width with inner retina attrition. These suggest abnormalities in inner retinal morphology or post-receptor signaling. Studying interactions between retinal vascular, structural, and functional changes could enhance knowledge of OIR pathogenesis and potential therapies.
BACKGROUND:Retinopathy of prematurity is a condition of abnormal retinal vascularization in premature infants. The effect of abnormal vascularization on retinal structure and function is unclear. In vivo studies of retinal vascularization, thickness, and function were performed in mice with oxygen-induced retinopathy (OIR mice). METHODS: Eighteen mice were exposed to hyperoxia at postnatal day (P) 7, whereas 18 mice were raised in room air (RA). At P20 and 40, electroretinogram was performed for a-wave and b-wave amplitudes and peak times, followed by simultaneous fluorescein angiography for retinal avascular area, arterial tortuosity, and vein dilation assessments, and spectral domain optical coherence tomography for retinal thickness. RESULTS: Capillary density appeared sparser in OIR mice, but retinal avascular area similar to RA mice. Retinal artery tortuosity was higher at P20 and P40 (P = 0.0001) in OIR than RA mice. OIR mice had dilated retinal veins at P20 and thinner inner retinas at P40. Retinal vein width positively correlated with inner retinal thickness (P = 0.008). b-wave amplitude was decreased in avascular retinal areas, and correlated with inner retinal thinning. b-wave peak time was prolonged in adult OIR mice at high intensities (P = 0.03). CONCLUSIONS: Focal variations in retinal vascularization of OIR mice correlate with thickness and function. Adult OIR mice had increased retinal artery tortuosity, prolonged b-wave peak time, and decreased retinal vein width with inner retina attrition. These suggest abnormalities in inner retinal morphology or post-receptor signaling. Studying interactions between retinal vascular, structural, and functional changes could enhance knowledge of OIR pathogenesis and potential therapies.
Authors: Haiying Cheng; Govind Nair; Tiffany A Walker; Moon K Kim; Machelle T Pardue; Peter M Thulé; Darin E Olson; Timothy Q Duong Journal: Proc Natl Acad Sci U S A Date: 2006-11-06 Impact factor: 11.205
Authors: Susumu Ishida; Tomohiko Usui; Kenji Yamashiro; Yuichi Kaji; Shiro Amano; Yuichiro Ogura; Tetsuo Hida; Yoshihisa Oguchi; Jayakrishna Ambati; Joan W Miller; Evangelos S Gragoudas; Yin-Shan Ng; Patricia A D'Amore; David T Shima; Anthony P Adamis Journal: J Exp Med Date: 2003-08-04 Impact factor: 14.307