Simultaneous fundus imaging and optical coherence tomography of the mouse retina

PURPOSE. To develop a retinal imaging system suitable for routine examination or screening of mouse models and to demonstrate the feasibility of simultaneously acquiring fundus and optical coherence tomography (OCT) images. METHODS. The imaging system is composed of a photographic slit lamp for biomicroscopic examination of the fundus, an OCT interferometer, an OCT beam delivery system designed for the mouse eye, and a mouse positioning stage. Image acquisition was controlled with software that displays the fundus and OCT images in real time, and allows the user to control the position of the OCT beam spot on the fundus image display. The anesthetized mouse was placed in a cylindrical holder on the positioning stage, and a single operator adjusted the position of mouse. RESULTS. Fundus images and OCT scans were successfully acquired in both eyes of 8 C57BL/6 mice. Once the animal is anesthetized and placed in the holder, a typical imaging experiment takes less than 2 minutes. The retinal vasculature, pigmentation, nerve fiber arrangement, and optic nerve head were clearly visible on the fundus images. The quality of the OCT images was sufficient to allow measurement of the total, inner, and outer retinal thicknesses and to visualize the optic nerve head excavation. CONCLUSIONS. The study demonstrates the feasibility of acquiring simultaneous fundus and OCT images of the mouse retina, by a single operator, in a manner suitable for routine evaluation of mouse models of retinal disease.