Effect of prophylactic topical hypotensive medications in reducing the incidence of postoperative ocular hypertension after phacoemulsification in dogs

Abstract

The latanoprost group had a substantially lower percentage of POH 20 and POH25 compared to the control and other active treatment groups, although statistical significance was not achieved. Intraoperative intracameral tissue plasminogen activator decreased the incidence of POH25.

Effect of immediate postoperative intracameral tissue plasminogen activator (tPA) on anterior chamber fibrin formation in dogs undergoing phacoemulsification

“…Anterior uveitis results in breakdown of the blood‐aqueous barrier, permitting leakage of plasma or whole blood components into the aqueous humor and subsequent fibrin formation. It has been postulated that intraocular fibrinous effusion contributes to synechiation, opacity along the visual axis, corneal endothelial damage, and postoperative ocular hypertension (POH) or secondary glaucoma via obstruction of the iridocorneal angle (ICA) . In humans and dogs, intracameral tPA is both safe and efficacious for clearing intraocular fibrin .…”

“…It has been postulated that intraocular fibrinous effusion contributes to synechiation, opacity along the visual axis, corneal endothelial damage, and postoperative ocular hypertension (POH) or secondary glaucoma via obstruction of the iridocorneal angle (ICA). 16,17 In humans and dogs, intracameral tPA is both safe and efficacious for clearing intraocular fibrin. 12,13,15 Clot dissolution is rapid, within minutes to hours of injection.…”

Treatment of canine postoperative ocular hypertension with combined latanoprost 0.005% and atropine 1% ophthalmic solutions

“…Treatment of POH in dogs includes aqueous paracentesis, intravenous mannitol, and oral or topical antiglaucoma medications . Published prevention protocols for POH are intracameral carbachol and topical antiglaucoma medications as dorzolamide and dozolamide combined with timlol maleate . The topical antiglaucoma medication “latanoprost” is a prostaglandin analog (PGA) that significantly decreases the IOP of dogs through binding of FP receptors, thereby increasing the uveoscleral outflow .…”

“…The decrease in IOP has been demonstrated to be as great as 50%‐60% in glaucomatous dogs, placing PGAs among the strongest antiglaucoma medications available for use in veterinary ophthalmology . In a study from 2017 by Dees et al, the PGA latanoprost had a substantially, but not significant, better effect on lowering IOP after phacoemulsification in dogs when compared to other antiglaucoma medications such as dorzolamide and dorzolamide/timolol. One side effect of topical PGAs, documented in both dogs and humans, is significant miosis .…”

“…1,2 Published prevention protocols for POH are intracameral carbachol and topical antiglaucoma medications as dorzolamide and dozolamide combined with timlol maleate. [7][8][9] The topical antiglaucoma medication "latanoprost" is a prostaglandin analog (PGA) that significantly decreases the IOP of dogs through binding of FP receptors, thereby increasing the uveoscleral outflow. 10,11 Prostaglandin analogs have also been suggested to decrease the production of aqueous humor from the ciliary body, 12 and it has also been suggested that PGAs may cause blood-ocular barrier disruption in normal dogs.…”