ELECTRORETINOGRAPHIC EVALUATION OF PAPILLONS WITH AND WITHOUT HEREDITARY RETINAL DEGENERATION

Objective-To evaluate the function of the outer retina in Papillons wi th and without hereditary retinal degeneration. Animals-45 Papillons, median age 1.7 (range, 0.8 to 5.1) years. Procedure-Complete physical and ophthalmic examinations were done prior to performing electroretin ography under general anesthesia. Full-field electroretinograms (ERG) were recorded, using a special-purpose computer system. Eleven specifi c ERG responses were recorded, graphed, and evaluated, using age-match ed Papillons. Results-Severely decreased retinal function was detected in 8 Papillons. The youngest affected dog was 1.2 years old. in affec ted dogs, amplitudes of responses mainly originating from the rod syst em were severely decreased, compared with those originating from the c one system. Conclusions-Papillons represent another breed of dog affec ted by a hereditary photoreceptor degeneration that can be detected at an early age by using ERG. A reliable age for diagnosis using ERG is considered to be 1.5 years, Clinical Relevance-Thorough and precise ER G procedures and protocols are needed to reliably obtain an early diag nosis of progressive retinal atrophy.