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Polyquaternium-1-Associated Dendritiform Keratopathy
Angela Verkade1, Alice Y Matoba
1Department of Ophthalmology, Baylor College of Medicine, Houston, TX.
Purpose:
To report a case of polyquaternium-1 (Polyquad, PQ-1)-associated dendritiform keratopathy that developed after exposure to the tear substitute Systane (Alcon Laboratories, Inc, Fort Worth, TX).
Methods:
A retrospective review of the case was performed.
Results:
Dendritiform keratopathy developed in the patient after an increase in the use of topical Systane from 4 times per day to every hour. Keratopathy resolved with discontinuation of Systane.
Conclusions:
Polyquaternium-1-associated dendritiform keratopathy can occur in patients who have previously tolerated the preservative. Because keratopathy seems to have developed and improved because of dose-dependent factors, the mechanism is more likely toxicity than hypersensitivity.
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