Does Tropicamide Influence Choroidal Thickness? Insights from Optical Coherence Tomography

Abstract

Purpose: To evaluate the effect of topical 1% tropicamide instillation on subfoveal choroidal thickness (SCT) and intraocular pressure in healthy eyes using optical coherence tomography (OCT). Methods: This study included 40 eyes of 20 healthy emmetropic participants. All subjects underwent comprehensive ophthalmic examination, including intraocular pressure measurement and axial length assessment. Swept-source OCT was performed before and 45 minutes after topical instillation of 1% tropicamide. SCT was measured using manual segmentation and software of the device. Measurements were independently evaluated by two masked observers. Statistical analysis was performed using paired-samples t test. Results: The mean age of the participants was 34.8 ± 10.1 years. Mean intraocular pressure was 16.1 ± 2.1 mmHg before and 16.5 ± 2.8 mmHg after tropicamide instillation, with no statistically significant difference (p > 0.05). Mean subfoveal choroidal thickness was 298.3 ± 30.5 µm before and 287.1 ± 35.2 µm after tropicamide administration. No statistically significant change in subfoveal choroidal thickness was observed following tropicamide instillation (p > 0.05). Conclusion: Topical administration of 1% tropicamide in healthy emmetropic eyes does not result in significant changes in intraocular pressure or subfoveal choroidal thickness, supporting its safety and reliability for routine posterior segment evaluation. These findings support the use of tropicamide as a practical and reliable mydriatic agent for routine ophthalmologic examinations, allowing posterior segment evaluation and related measurements to be performed without compromising patient comfort or clinical workflow.

Keywords

• Choroidal thickness
• Intraocular pressure
• Optical coherence tomography
• Tropicamide

References

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