Steroid-induced ocular hypertension in normal sheep

Area of Science:

• Ophthalmology
• Veterinary Medicine
• Pharmacology

Background:

• Corticosteroids are widely used for their anti-inflammatory properties.
• Topical corticosteroid use can lead to elevated intraocular pressure (IOP) in susceptible individuals.
• Understanding the mechanisms of steroid-induced ocular hypertension is crucial for managing glaucoma.

Purpose of the Study:

• To investigate the effect of topical prednisolone acetate on intraocular pressure (IOP) in an ovine model.
• To determine if corticosteroid application induces ocular hypertension in sheep eyes.

Main Methods:

• Eighteen sheep were treated with topical 0.5% prednisolone acetate in one eye for 3-4 weeks.
• Intraocular pressure (IOP) was measured using Perkins applanation tonometry.
• IOP was monitored during treatment and for 1-3 weeks after discontinuation.

Main Results:

• Baseline IOP in sheep eyes was approximately 10.6 mm Hg.
• Prednisolone treatment led to a significant increase in IOP, peaking at 27.5 mm Hg in treated eyes compared to 11.7 mm Hg in control eyes.
• IOP returned to baseline levels within 1-3 weeks after stopping corticosteroid treatment.

Conclusions:

• Ovine eyes demonstrate a consistent and significant steroid-induced ocular hypertensive response to topical corticosteroids.
• This finding suggests that the ovine eye can serve as a relevant model for studying steroid-induced glaucoma.
• The study provides potential insights into the mechanisms underlying primary open-angle glaucoma and its treatment.