Abstract
A project was started at the Amneville zoo in France to desensitize sea lions for voluntary eye ultrasound. There have been several reviews and publications about pinniped eye disease1,2,4,5 and surgery6,8 recently and references on the sea lion eye anatomy through ultrasound seemed appropriate3,7. A Logiq e VET and Logiq e BT12 with I8-18 RS, 12L-RS, 8C-RS and 4C-RS probes from General Electrics were used, with the preference given to the I8-18 RS probe. Different positions for the animals, the trainers and the veterinarian were tested such as to have the most comfortable access to scan the eyes. Both open, after utilization of topical anesthetic or in-water scanning, and closed eye ultrasounds were performed in several animals to record images and videos of the eye. Reference images of the internal eye structures were henceforth obtained. Ultrasound can help in the diagnose of retinal detachment, foreign bodies, swelling/inflammation, tumors and other disorders that are sometimes difficult to identify through lack of pupillary dilatation and/or direct ophthalmoscopy. Identification of cataract and anterior luxation are high on the list. Surgical removal of the lens has become more frequent in pinnipeds,8 generally through an intra- or extracapsular approach upon full ripening of the lens. The training allowed for the follow-up of cataract development in an animal and the identification of early cataractous changes in another. This early detection through ultrasound may potentially allow a surgery by phaecoemulsification, less invasive and the most widely used cataract surgery nowadays, because performed at an earlier development of the disease. Ultrasonic examination of the eye is also seen as a helpful diagnostic tool pre- and post-surgery.
Acknowledgements
SCIL France, distributor of the GE ultrasound machines in France, sponsored the project by providing the equipment.
* Presenting author
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