Design of a Compact Table-Top Retinal Imaging System for the Mouse

Abstract

Purpose: : To develop a compact table-top imaging system for simultaneous fundus and Optical Coherence Tomography (OCT) imaging of the mouse retina.

Methods: : A compact mouse retinal imaging system providing fundus and OCT images was designed. The mouse fundus imaging system used a digital CCD camera (XCD-SX910CR, Sony, Park Ridge, NJ) with a lens objective and 90 D auxiliary lens (Volk, Mentor, OH). The retina was illuminated with one bright white light-emitting diode (LED) (LED1, Dessau, Germany). The OCT images were acquired with a time-domain system. The OCT beam was coupled on to the optical axis of the fundus camera with a hot mirror and delivered to the mouse eye through the auxiliary Volk lens. The fundus and OCT images are displayed in real-time on a computer monitor. A 6-axis positioning system was mounted in front of the auxiliary lens to align the mouse eye with the optical axis. Fundus and OCT images of C57Bl6 anesthetized mice were acquired simultaneously. The mouse body temperature was controlled during the experiment. To avoid dehydration, one drop of Balanced Salt Solution is applied to the corneal surface at the beginning of the experiment.

Results: : Eight eyes of 4 C57Bl6 mice were successfully imaged. The optic nerve head, vasculature, and nerve fiber layer could be visualized on the fundus images. The system allowed acquisition of OCT images in regions of interest by controlling the position of the OCT scan in real-time with the guidance of the fundus image.

Conclusions: : A compact table-top mouse retinal imaging system suitable for rapid examination of the mouse retina was developed and successfully tested on C57Bl6 mice.

Keywords: retina • imaging methods (CT, FA, ICG, MRI, OCT, RTA, SLO, ultrasound) • laser