Jennifer C Kwok, Yu Sato, Jessica K Niggel, Emma Ozdogan, Leonardo Murgiano, Keiko Miyadera
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引用次数: 0
Abstract
Objective: Cone-rod dystrophy (cord1) is a form of progressive retinal atrophy. It is linked to an RPGRIP1 genetic variant which is the third most common canine disease variant thus far. While the variant affects various breeds, it is highly prevalent in English Springer Spaniels (ESSs). Yet its clinical and pathological implications remain equivocal. Herein, we study the retinal phenotype in ESSs genetically affected with the RPGRIP1 variant.
Animal studied: Over 4 years, 494 ESSs (123 affected) were enrolled.
Procedure(s): Owner-perceived vision was collected via a questionnaire. Ophthalmic examination included fundus photography. In selected ESSs, retinal function and structure were assessed using electroretinography (ERG, 148 dogs) and optical coherence tomography (OCT, 4 dogs).
Results: Ophthalmoscopic changes included peripheral hypo-reflective lesions often with distinct borders progressing centripetally culminating in generalized retinal atrophy. Cross-sectional study revealed declining photopic ERG amplitudes with age in the affected group but not in controls. OCT indicated progressive photoreceptor loss. Despite ophthalmoscopic, ERG, or OCT abnormalities, most affected dogs were not visually impaired per their owners. In a fraction of afflicted ESSs, vision/globe-threatening complications were documented including cataracts, lens luxation, and glaucoma.
Conclusions: In ESSs, the RPGRIP1 variant is associated with insidious pathology with delayed-onset visual defects. The subtle phenotype without apparent visual deficit until the final years of life, if at all, may have caused underdiagnosis of cord1. Still, DNA testing remains informative, and ERG and OCT indicate progressive pathology. Peripheral fundus examination and photopic ERG are particularly useful for early detection and monitoring of cord1.
期刊介绍:
Veterinary Ophthalmology is a peer-reviewed, international journal that welcomes submission of manuscripts directed towards academic researchers of veterinary ophthalmology, specialists and general practitioners with a strong ophthalmology interest. Articles include those relating to all aspects of:
Clinical and investigational veterinary and comparative ophthalmology;
Prospective and retrospective studies or reviews of naturally occurring ocular disease in veterinary species;
Experimental models of both animal and human ocular disease in veterinary species;
Anatomic studies of the animal eye;
Physiological studies of the animal eye;
Pharmacological studies of the animal eye.