Objective:

To highlight the risks associated with the use of petrolatum-based ophthalmic ointments in patients with PRESERFLO MicroShunt implants.

Key Findings:

• MicroShunt swelling was observed in all three clinical cases after the application of petrolatum-based ointment.
• The swelling was localized to the exposed, subconjunctival portion of the MicroShunt, while the intraocular segment remained relatively unchanged.
• Four explanted MicroShunts from patients without ointment exposure showed no swelling, supporting the link between ointment contact and device swelling.

Interpretation:

Direct contact with petrolatum-based ointment is a key trigger for swelling and potential structural failure of the MicroShunt, particularly when the device is exposed.

Limitations:

• The study is based on a small number of clinical cases.
• Further research is needed to explore the long-term implications of this complication.

Conclusion:

Clinicians should avoid using petrolatum-based ophthalmic ointments in patients with exposed MicroShunts to prevent this rare but serious complication.