Vitreous cavity replacement with SiO is indicated in complex retinal reattachment surgery in dogs by providing long-term retinal tamponade. Use of SiO in dogs is desirable because they are unable to maintain a stable head position for several hours per day and because of the extensive nature of retinal detachment in dogs. Several complications have been reported for SiO use as a permanent tamponade in humans,1 rabbits,2 nonhuman primates,3 and dogs.4,5 These complications include SiO emulsification,1,6 anterior chamber migration,4,5 keratopathy,6–8 glaucoma,2 cataract formation,5 inner retinal toxic effects,9–11 and subconjunctival migration from sclerotomy sites.9
Keratopathy and glaucoma are more common in aphakic and, to a lesser extent, pseudophakic eyes, potentially allowing easier access of oil to the anterior chamber than in other eyes.10,11 Keratopathy and glaucoma in dogs are more likely to develop with emulsification of the SiO in the anterior chamber. Emulsification occurs more commonly with less viscous versus more viscous SiOs and with SiOs containing higher versus lower amounts of impurities.
Removal of SiO from canine and human eyes can lead to retinal slippage or recurrence of the retinal detachment. In dogs, SiO is rarely removed, whereas in humans, removal is performed most often between 2 and 6 months after surgery to help avoid cataract formation and proliferative vitreoretinopathy and to correct anisometropia.6 Given that the refractive indices of SiO and vitreous humor are different (1.405 and 1.336 D, respectively),12 surgeons should consider the possible refractive changes induced following vitreous humor replacement, which, to the authors' knowledge, has not been determined in dogs. The purpose of the study reported here was to evaluate ocular refractive error following retinal reattachment surgery and SiO tamponade in dogs.
Fluress, Akorn Inc, Lake Forest, Ill.
Intervet/Schering-Plough Animal Health Inc, Roseland, NJ.
TonoVet, Tiolat TV01, Helsinki, Finland.
Kowa SL-14 portable slit lamp, CR Medical, Linz, Austria.
Keeler Wireless, Keeler Ltd, Windsor, Berkshire, England.
Acri.Octa, S.V. & Technologies AG, Hennigsdorf, Germany.
Acri.SIL-OL. S V. & Technologies AG, Hennigsdorf, Germany.
OPMI-6-S, Carl Zeiss AG, Aalen, Germany.
VOLK ROLS, Mentor, Ohio.
Eibos HS, Möeller-Wedel GmbH, Wedel, Germany.
MedOne Surgical Inc, Sarasota, Fla.
Dutch Ophthalmic, Exeter, NH.
Alcon Laboratories Inc, Fort Worth, Tex.
DioVet, Iridex Corp, Mountainview, Calif.
Ethicon Inc, Somerville, NJ.
Heine BETA TR 3.5 V, Heine Optotechnik GmbH & Co, Herrsching, Germany.
L2 Retinoscopy racks, Luneau Ophtalmologie, Chartres Cedex, France.
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