# Topical Prednisolone Acetate Challenge as a Predictor of Intraocular Pressure Elevation Following Ozurdex® in Diabetic Macular Edema: A Retrospective Study

## TL;DR

This study shows that a short eye drop treatment with prednisolone can help predict if a patient's eye pressure will rise after a steroid implant used for diabetic eye disease.

## Contribution

The study introduces a low-cost topical steroid challenge as a potential predictor of intraocular pressure elevation after Ozurdex implantation.

## Key findings

- IOP increased significantly after both the topical steroid challenge and Ozurdex implantation.
- A moderate correlation was found between IOP change after the topical challenge and post-Ozurdex IOP rise.
- Only 7.4% of patients experienced clinically significant IOP elevation, managed medically.

## Abstract

Background

Steroid-induced ocular hypertension remains a practical concern with intravitreal corticosteroid therapy. The dexamethasone implant (Ozurdex®) is widely used for diabetic macular edema (DME), yet increases in intraocular pressure (IOP) can still occur. Identifying patients at greater risk before treatment would allow more tailored counseling and follow-up. This study examined whether a short topical prednisolone acetate challenge can anticipate the IOP response to Ozurdex in routine care within a Middle Eastern cohort.

Methods

This retrospective, observational study included 27 eyes of 27 patients with DME treated at Salmaniya Medical Complex, Kingdom of Bahrain. All patients underwent a topical prednisolone acetate 1% challenge (QID for three to four weeks) before Ozurdex implantation. IOP was measured at baseline, after the topical challenge, and six to eight weeks post-Ozurdex using Topcon non-contact tonometry. The primary outcome was a clinically significant IOP rise after Ozurdex (≥10 mmHg). Friedman and Wilcoxon signed-rank tests were used for within-eye comparisons; correlation was assessed with Spearman’s ρ.

Results

Mean baseline IOP was 18.4±2.2 mmHg, increasing to 19.6±2.5 mmHg after topical steroid challenge and 21.4±5.5 mmHg at six to eight weeks post-Ozurdex. Across the three timepoints, IOP differed significantly (χ²=14.47, p=0.0007). Pairwise comparisons confirmed significant rises from baseline to challenge (p=0.0034) and from baseline to Ozurdex (p=0.0033). The IOP change after topical challenge correlated moderately with post-Ozurdex IOP rise (Spearman’s ρ=0.52, p=0.005). Clinically significant IOP elevation (≥10 mmHg) occurred in two eyes (7.4%), all managed medically without surgery.

Conclusion

A short-term topical prednisolone acetate challenge provides moderate predictive value for identifying eyes at risk of IOP elevation following Ozurdex implantation. While not a perfect predictor, this inexpensive and non-invasive test may assist clinicians in tailoring post-injection monitoring strategies, particularly in resource-limited or high-volume care settings.