In Vivo Confocal Microscopy Features of Corneal Dystrophy in Siberian Huskies.

Objective: To describe the morphological features of corneal dystrophy in Siberian Huskies using in vivo confocal microscopy (IVCM).

Animals studied: Twenty-one dogs.

Procedures: A prospective case-control study was performed. Siberian Huskies with (n = 13 dogs) and without (n = 8) corneal dystrophy were evaluated. Complete ophthalmic and IVCM examinations (Heidelberg Retina Tomograph and Rostock Cornea Module) were performed for each case.

Results: All dogs with corneal dystrophy demonstrated characteristic bilateral, round-to-oval, refractile, crystalline corneal opacities visible within the stroma by slit-lamp biomicroscopy. The median age of dogs with corneal dystrophy was 5.0 years (range: 2-13 years), with eight females and five males included. During IVCM, dense accumulations of fine, needle-like, tapered, hyperreflective structures were present within the axial corneal stroma of each dog. The length of the spindles varied from several μm to > 400 μm and the structures were commonly present in dense clumps. Amorphous, thicker, crystalline deposits with blunted ends were present less frequently and intermixed with the needle-like structures. Other corneal anatomic features were generally obscured by the deposits, but the surrounding regions appeared morphologically normal, including the epithelium, keratocytes, corneal nerves, and endothelium. Siberian Huskies without corneal dystrophy were presented for various other ophthalmic conditions, including cataracts and primary glaucoma. The median age of control dogs was 1.5 years (range: 1-9 years), with five females and three males included. Similar hyperreflective deposits were not detected by IVCM in any dogs from the control group.

Conclusions: Application of IVCM can aid in the characterization of corneal dystrophies in Siberian Huskies.