Premium
Ultrasonographic features of PMEL 17 ( S ilver ) mutant gene–associated multiple congenital ocular anomalies ( MCOA ) in C omtois and R ocky M ountain horses
Author(s) -
Ségard Emilie M.,
Depecker Marianne C.,
Lang Johann,
Gemperli Armin,
Cadoré JeanLuc
Publication year - 2013
Publication title -
veterinary ophthalmology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.594
H-Index - 50
eISSN - 1463-5224
pISSN - 1463-5216
DOI - 10.1111/vop.12021
Subject(s) - ophthalmoscopy , ultrasound , medicine , cornea , ophthalmology , pathology , ultrasonography , cataracts , hypoplasia , uvea , echogenicity , anatomy , retinal , eye disease , surgery , radiology
Abstract Objective (1) To describe the ultrasonographic appearance of multiple congenital ocular anomalies ( MCOA ) in the eyes of horses with the PMEL 17 ( S ilver ) mutant gene. (2) To compare the accuracy of B‐mode ocular ultrasound to conventional direct ophthalmoscopy. Animals studied Sixty‐seven C omtois and 18 R ocky M ountain horses were included in the study. Procedures Horses were classified as being carriers or noncarriers of the PMEL 17 mutant allele based on coat color or genetic testing. Direct ophthalmoscopy followed by standardized ultrasonographic examination was performed in all horses. Results Seventy‐five of 85 horses (88.24%) carried at least one copy of the S ilver mutant allele. Cornea globosa, severe iridal hypoplasia, uveal cysts, cataracts, and retinal detachment could be appreciated with ultrasound. Carrier horses had statistically significantly increased anterior chamber depth and decreased thickness of anterior uvea compared with noncarriers ( P < 0.05). Uveal cysts had a wide range of location and ultrasonographic appearances. In 51/73 (69.86%) carrier horses, ultrasound detected ciliary cysts that were missed with direct ophthalmoscopy. Conclusions In this study, ultrasonography was useful to identify uveal cysts in PMEL 17 mutant carriers and to assess anterior chamber depth.