Purchase this article with an account.
Yichao Li, Lian Zhao, Wai T Wong, Haohua Qian; A new non-invasive method for detecting retinal vasculature using blue reflectance scanning laser ophthalmoscope. Invest. Ophthalmol. Vis. Sci. 2014;55(13):203.
Download citation file:
© ARVO (1962-2015); The Authors (2016-present)
Confocal scanning laser ophthalmoscope (cSLO) is a widely used diagnostic tool for retinal diseases. We used cSLO imaging in the blue reflectance (BR) mode to identify new anatomical features that can be used non-invasively to monitor retinal structure and disease progression.
Infra-red (IR; 820 nm) and BR (488 nm) images of mouse fundus were captured with the Spectralis cSLO system. Fluorescein angiography (FA) was used to reveal the structure of retinal blood vessels. Images were analyzed using ImageJ and Volocity 3D Software (PerkinElmer Inc.).
Dark-appearing dots approximately 10 to 15 µm in diameter were observed on BR images in the inner retina below the level of the optic nerve fiber layer. These dark dots did not co-localize with the fluorescent signal in transgenic Cx3cr1-GFP mouse, indicating that they did not correspond to retinal microglia. They however co-localized well with intense fluorescent spots viewed on FA. 3D structure of retinal vasculature reconstructed from fluorescent tomography confirmed that fluorescent spots in FA images corresponded to connecting points of inner deeper plexus linking primary plexus and outer deeper plexus. In adult WT (C57Bl6) mouse, BR dots were distributed with regular spacing in all four quadrants of the retina; mean dot densities were 90±8, 76±4, 85±5, 89±3 dots/mm2, (mean±SD) for dorsal, ventral, nasal and temporal regions, respectively. Mouse models of retinal degeneration demonstrated lower densities of BR dots compared with WT mice. BR dot densities were 92±7, 32±5 and 50±5 dots/mm2, (mean±SD) for WT (postnatal age 2 month) (n=8), rd1 (postnatal age 1 month) (n=2) and rd10 (postnatal age 3 month) (n=4), respectively.
We discovered that the location, density, and distribution of connecting vessels in the retinal vasculature can be visualized non-invasively as dark dots on BR reflectance imaging. The number of dark dots decreased in mice with retinal degeneration, reflecting concurrent vascular degeneration in these models. BR dots represent a novel, non-invasive, imaging outcome measure that can be used to monitor vascular structure in normal retina and degeneration in retinal disease.
This PDF is available to Subscribers Only