Extracupsular Lens Extraction Combined with Phacoemulsification and Aspiration for Bilateral Cataracts in an Adult South American Fur Seal (Arctocephalus australis)
Abstract
Cataracts are the second most common eye problem in otariids.1 Only a few cases of phacoemulsification and aspiration (PEA) on young pinnipeds were reported.2,3 However, PEA is generally not appropriate in mature pinnipeds because of their very dense lens nucleus.
In this case, we successfully performed extracapsular lens extraction (ECLE) combined with PEA on an adult female South American fur seal (Arctocephalus australis). A seven-year-old female South American fur seal at the Enoshima Aquarium developed bilateral cataracts in her left eye over 15 months and over 9 months in the right eye. Visual impairment in both eyes had progressed.
Ophthalmic examination including slit-lamp biomicroscopy, tonometry, ultrasonography and fluorescein stain was performed on the animal under voluntary behavior developed by the Enoshima Aquarium’s husbandry training program. Examination revealed bilateral hypermature cataracts, lens induced uveitis (LIU) and no lens luxation. Prior to surgery, oral and topical treatment with NSAIDs were initiated for LIU.
Bilateral cataracts surgery was planned to be performed by intracapsular lens extraction (ICLE). Sufficient mydriasis for ICLE could not be achieved in spite of intracameral administration of 1:1,000 epinephrine and intraocular hemorrhage was observed. The surgical plan was changed to ECLE combined with PEA. PEA were performed to remove lens cortex and epinucleus followed by ECLE for removing fragments of lens nucleus. By performing PEA first, ECLE could be achieved with the small pupil. Vision was restored on the first day after surgery. There was also mild blepharospasms, corneal edema, post-operative uveitis, and posterior synechia. Vision in the left eye took longer to restore than the right eye. Secondary cataract has not observed in the 3 months after surgery.
ECLE with PEA can be effective for cataracts in adult pinniped and may reduce intra-operative and post-operative complications.
Acknowledgements
The authors wish to thank Dr. Takaomi Ito of Osaka Aquarium Kaiyukan, Dr. Masahiko Kasamatsu of Toba Aquarium, Dr. Kenji Teshima of Nihon Unversity for management of anesthesia and Meni-one Co., Ltd for allowing us to use surgical microscopy. The author also thank all marine mammal trainers of the Enoshima Aquarium for their excellent care to the animal.
Literature Cited
1. Kern TJ, Colitz CMH. 2013. Exotic animal ophthalmology. In: Gelatt KN, Gilger BC, Kern TJ, eds. Veterinary Ophthalmology, 5th ed. Ames, IA: Wiley-Blackwell; 1782–1793.
2. Esson DW, Nollens HH, Schmitt TL, Fritz KJ, Simeone CA, Stewart BS. 2015. Aphakic phacoemulsification and automated anterior vitrectomy, and postreturn monitoring of a rehabilitated harbor seal (Phoca vitulina richardsi) pup. J Zoo Wildl Med. 46:647–651.
3. Barnes JA, Smith JS. 2004. Bilateral phacofragmentation in a New Zealand fur seal (Arctocephalus forsteri). J Zoo Wildl Med. 35:110–112.