Effects of topical corticosteroid administration on intraocular pressure in normal and glaucomatous cats

Abstract

Objective to determine the effect of topical corticosteroid (CCS) therapy on intraocular pressure (IOP) in normal cats and cats with primary feline congenital glaucoma (FCG). Animals studied 5 normal and 11 FCG cats were studied in 2 cohorts. Procedures IOP was measured by a single, masked observer, once daily 3–5 days/week throughout the course of CCS treatment and for up to 11 days after treatment discontinuation. One eye per cat was randomly assigned for treatment twice daily with CCS; Balanced salt solution (BSS) applied to the contralateral eye, served as a control. Differences between eyes and between weeks of the study period were calculated for each cat. A positive response to CCS was defined as a consistent >15% or >25% higher IOP in the treated relative to control eye in normal and FCG cats, respectively. Results 8/11 FCG cats responded to topical CCS after 1–5 weeks of treatment with an increase in IOP relative to the untreated eye (maximum IOP discrepancy of 56 mmHg). 2/5 normal cats responded to topical CCS with appreciable but clinically unimportant increase in IOP in the treated eye (maximum IOP discrepancy of 6.4 mmHg). Conclusions our data indicate that the incidence of steroid induced IOP elevation in cats is lower than previously published feline studies suggest. Cats with pre-existing compromise in aqueous humor outflow may show a greater, clinically relevant response to topical CCS than normal cats.

Model systems for the study of steroid-induced IOP elevation

“…However, more recent work indicated that the responsiveness of normal cats may be lower than initially reported (Gosling et al, 2016). Thus, the feline steroid induced IOP elevation continues to be a potentially useful, albeit somewhat underutilized animal model.…”

Model systems for the study of steroid-induced IOP elevation

“…However, more recent work indicated that the responsiveness of normal cats may be lower than initially reported (Gosling et al, 2016). Thus, the feline steroid induced IOP elevation continues to be a potentially useful, albeit somewhat underutilized animal model.…”

Treatment With Remdesivir Alone or in Combination With GS-441524 in Cats With Ocular Involvement of Feline Infectious Peritonitis: An Observational Case Series

“…Clinicians should be vigilant for uveitis‐associated secondary glaucoma and perform tonometry at regular intervals, particularly in uveitic eyes which have inappropriate normal to high‐normal intraocular pressure. Carbonic anhydrase inhibitors are the topical treatment of choice for cats with secondary glaucoma, and steroid‐induced ocular hypertension should be considered as a potential contributing factor [ 30 , 31 ].…”

Effects of intracameral tissue plasminogen activator injection on posterior capsular opacification, fibrin formation, and intraocular pressure in dogs after phacoemulsification

“…In this study, we used 1% prednisolone acetate eye drops for postoperative treatment, except for in participants with diabetes. Steroid effects and IOP elevation are related to long‐term use of steroids (lasting more than a week) 29–33 . Corticosteroids induce mechanical and biochemical changes within the trabecular meshwork, leading to an increase IOP by increasing aqueous humor outflow resistance, perhaps by altering the extracellular matrix components within the aqueous outflow pathway, inhibition of proteases and phagocytosis within the trabecular meshwork, and alterations in the morphology of the trabecular meshwork cells 34–36 .…”

“…Corticosteroids induce mechanical and biochemical changes within the trabecular meshwork, leading to an increase IOP by increasing aqueous humor outflow resistance, perhaps by altering the extracellular matrix components within the aqueous outflow pathway, inhibition of proteases and phagocytosis within the trabecular meshwork, and alterations in the morphology of the trabecular meshwork cells 34–36 . Topical corticosteroids are associated with elevations in IOP of primary open‐angle glaucoma in human, 29,34 rabbits, 30 and cats 31,32 . However, no correlation between IOP and topical administration of 1% prednisolone acetate has been reported in normal canine eyes 33 .…”

“…Steroid effects and IOP elevation are related to long‐term use of steroids (lasting more than a week). 29 , 30 , 31 , 32 , 33 Corticosteroids induce mechanical and biochemical changes within the trabecular meshwork, leading to an increase IOP by increasing aqueous humor outflow resistance, perhaps by altering the extracellular matrix components within the aqueous outflow pathway, inhibition of proteases and phagocytosis within the trabecular meshwork, and alterations in the morphology of the trabecular meshwork cells. 34 , 35 , 36 Topical corticosteroids are associated with elevations in IOP of primary open‐angle glaucoma in human, 29 , 34 rabbits, 30 and cats.…”

Model systems for the study of steroid-induced IOP elevation

“…However, more recent work indicated that the responsiveness of normal cats may be lower than initially reported (Gosling et al, 2016). Thus, the feline steroid induced IOP elevation continues to be a potentially useful, albeit somewhat underutilized animal model.…”

Treatment With Remdesivir Alone or in Combination With GS-441524 in Cats With Ocular Involvement of Feline Infectious Peritonitis: An Observational Case Series

“…Clinicians should be vigilant for uveitis‐associated secondary glaucoma and perform tonometry at regular intervals, particularly in uveitic eyes which have inappropriate normal to high‐normal intraocular pressure. Carbonic anhydrase inhibitors are the topical treatment of choice for cats with secondary glaucoma, and steroid‐induced ocular hypertension should be considered as a potential contributing factor [ 30 , 31 ].…”

Effects of intracameral tissue plasminogen activator injection on posterior capsular opacification, fibrin formation, and intraocular pressure in dogs after phacoemulsification

“…In this study, we used 1% prednisolone acetate eye drops for postoperative treatment, except for in participants with diabetes. Steroid effects and IOP elevation are related to long‐term use of steroids (lasting more than a week) 29–33 . Corticosteroids induce mechanical and biochemical changes within the trabecular meshwork, leading to an increase IOP by increasing aqueous humor outflow resistance, perhaps by altering the extracellular matrix components within the aqueous outflow pathway, inhibition of proteases and phagocytosis within the trabecular meshwork, and alterations in the morphology of the trabecular meshwork cells 34–36 .…”

“…Corticosteroids induce mechanical and biochemical changes within the trabecular meshwork, leading to an increase IOP by increasing aqueous humor outflow resistance, perhaps by altering the extracellular matrix components within the aqueous outflow pathway, inhibition of proteases and phagocytosis within the trabecular meshwork, and alterations in the morphology of the trabecular meshwork cells 34–36 . Topical corticosteroids are associated with elevations in IOP of primary open‐angle glaucoma in human, 29,34 rabbits, 30 and cats 31,32 . However, no correlation between IOP and topical administration of 1% prednisolone acetate has been reported in normal canine eyes 33 .…”

“…Steroid effects and IOP elevation are related to long‐term use of steroids (lasting more than a week). 29 , 30 , 31 , 32 , 33 Corticosteroids induce mechanical and biochemical changes within the trabecular meshwork, leading to an increase IOP by increasing aqueous humor outflow resistance, perhaps by altering the extracellular matrix components within the aqueous outflow pathway, inhibition of proteases and phagocytosis within the trabecular meshwork, and alterations in the morphology of the trabecular meshwork cells. 34 , 35 , 36 Topical corticosteroids are associated with elevations in IOP of primary open‐angle glaucoma in human, 29 , 34 rabbits, 30 and cats.…”

Model systems for the study of steroid-induced IOP elevation

“…However, more recent work indicated that the responsiveness of normal cats may be lower than initially reported (Gosling et al, 2016). Thus, the feline steroid induced IOP elevation continues to be a potentially useful, albeit somewhat underutilized animal model.…”

Treatment With Remdesivir Alone or in Combination With GS-441524 in Cats With Ocular Involvement of Feline Infectious Peritonitis: An Observational Case Series

“…Clinicians should be vigilant for uveitis‐associated secondary glaucoma and perform tonometry at regular intervals, particularly in uveitic eyes which have inappropriate normal to high‐normal intraocular pressure. Carbonic anhydrase inhibitors are the topical treatment of choice for cats with secondary glaucoma, and steroid‐induced ocular hypertension should be considered as a potential contributing factor [ 30 , 31 ].…”

Effects of intracameral tissue plasminogen activator injection on posterior capsular opacification, fibrin formation, and intraocular pressure in dogs after phacoemulsification

“…In this study, we used 1% prednisolone acetate eye drops for postoperative treatment, except for in participants with diabetes. Steroid effects and IOP elevation are related to long‐term use of steroids (lasting more than a week) 29–33 . Corticosteroids induce mechanical and biochemical changes within the trabecular meshwork, leading to an increase IOP by increasing aqueous humor outflow resistance, perhaps by altering the extracellular matrix components within the aqueous outflow pathway, inhibition of proteases and phagocytosis within the trabecular meshwork, and alterations in the morphology of the trabecular meshwork cells 34–36 .…”

“…Corticosteroids induce mechanical and biochemical changes within the trabecular meshwork, leading to an increase IOP by increasing aqueous humor outflow resistance, perhaps by altering the extracellular matrix components within the aqueous outflow pathway, inhibition of proteases and phagocytosis within the trabecular meshwork, and alterations in the morphology of the trabecular meshwork cells 34–36 . Topical corticosteroids are associated with elevations in IOP of primary open‐angle glaucoma in human, 29,34 rabbits, 30 and cats 31,32 . However, no correlation between IOP and topical administration of 1% prednisolone acetate has been reported in normal canine eyes 33 .…”

“…Steroid effects and IOP elevation are related to long‐term use of steroids (lasting more than a week). 29 , 30 , 31 , 32 , 33 Corticosteroids induce mechanical and biochemical changes within the trabecular meshwork, leading to an increase IOP by increasing aqueous humor outflow resistance, perhaps by altering the extracellular matrix components within the aqueous outflow pathway, inhibition of proteases and phagocytosis within the trabecular meshwork, and alterations in the morphology of the trabecular meshwork cells. 34 , 35 , 36 Topical corticosteroids are associated with elevations in IOP of primary open‐angle glaucoma in human, 29 , 34 rabbits, 30 and cats.…”