Mouse fundus photography and angiography: a catalogue of normal and mutant phenotypes

Mice are an increasingly important tool in ophthalmic research. As a result of studying spontaneous and induced mutations, many new ocular diseases have been described in mice in recent years, including several degenerative retinal diseases that demonstrate progression with age. Clearly, documentation of progressive changes in clinical phenotype is an important facet of characterizing new mutations and for comparing them with human diseases. Despite these facts, there are few published photographs of mouse fundi. The small size of the mouse eye and the steep curvature of its structures have made it difficult to obtain high quality fundus photographs. The purpose of this work was to develop procedures for mouse fundus photography and angiography and to use these techniques to examine several new mouse strains with ocular abnormalities.

We have used a small animal fundus camera and condensing lens to develop a reliable technique for producing high quality fundus images of conscious albino and pigmented mice. The fundus camera also was utilized to develop a method for fluorescein angiography, which demonstrated the normal retinal vascular bed as well as abnormal vascular leakage. In addition, several mouse strains with previously unreported ocular abnormalities (including two with inherited optic nerve colobomas) and a catalogue of previously unpublished clinical images for various mutant mice are presented.

Altogether, we provide clinical images for C57BL/6J, BALB/cByJ, retinal degeneration 1 (rd1), Rd2, rd3, rd7, achondroplasia, nervous, motor neuron degeneration, Purkinje cell degeneration, kidney and retinal defects, optic nerve coloboma 1, and two apparently multigenic optic nerve colobomas in a strain of mixed derivation (ONC) and the inbred CALB/Rk strain.

Our photography procedure reliably produces high quality images of the mouse fundus. This permitted us to record progressive retinal changes over time in the same animal, allowed us to compare the phenotypes of newly discovered retinal mutants to existing mutants at other institutions and to potentially similar human conditions, and finally, permitted us to produce a catalogue of previously unpublished clinical phenotypes for various mutant mice.