This paper was presented at the ECVDI/EAVDI Annual Conference 2007, Greece.
ULTRASONOGRAPHIC EVALUATION OF VITREOUS DEGENERATION IN NORMAL DOGS
Article first published online: 3 MAR 2008
© Copyright 2008 by the American College of Veterinary Radiology
Veterinary Radiology & Ultrasound
Volume 49, Issue 2, pages 165–171, March–April 2008
How to Cite
LABRUYÈRE, J. J., HARTLEY, C., ROGERS, K., WETHERILL, G., McCONNELL, J. F. and DENNIS, R. (2008), ULTRASONOGRAPHIC EVALUATION OF VITREOUS DEGENERATION IN NORMAL DOGS. Veterinary Radiology & Ultrasound, 49: 165–171. doi: 10.1111/j.1740-8261.2008.00344.x
- Issue published online: 3 MAR 2008
- Article first published online: 3 MAR 2008
- Received August 9, 2007; accepted for publication October 11, 2007.
- ocular ultrasonography;
- vitreous degeneration;
- asteroid hyalosis;
Vitreous degeneration is common in dogs and may be associated with cataract formation. Vitreous degeneration may be identified using B-mode ultrasonography and appears as multiple, small, motile, point-like echoes within the vitreous cavity. In humans, vitreous degeneration has also been observed in normal aging eyes but the incidence of vitreous degeneration in dogs without cataract has not previously been documented. The purpose of this study was to describe the ultrasonographic appearance of vitreous degeneration and to investigate its incidence in a population of dogs without cataract or other apparent eye disease. The eyes of 62 dogs were evaluated as part of a prospective study. All dogs underwent ophthalmological and ultrasonographic examinations and vitreal changes were graded on ultrasonography using a predetermined grading scheme. Vitreous degeneration was found in 20% (23/114) of the eyes on ultrasonographic examination but in only 8% (9/114) of eyes on direct ophthalmoscopy. Sensitivity and specificity of ophthalmoscopy using ultrasonography as a gold standard were respectively, 39% and 100%. Vitreal syneresis and asteroid hyalosis could be distinguished according to their ultrasonographic characteristics. The probability of having vitreous degeneration increased with the age of the dog (odds ratio=6.7 for dogs of 7+ years compared with 0–6 years) and also increased in females compared with males (odds ratio=3.6). Vitreous degeneration, especially mild vitreal syneresis, is not uncommon in normal dogs; it was shown to be an age-related condition and its significance should not be overinterpreted on ocular ultrasonography.