Toxic corneal ulcer: a frequent and sight-threatening disease.

PURPOSE: Overtreatment with topical ophthalmic preparations can lead to toxic corneal ulcer development. This study aimed to investigate the clinical and visual impact of toxic corneal ulcers and the management and risk factors for their development and outcomes.

METHODS

Clinical records of 226 consecutive patients with corneal ulcers referred to our tertiary care center were retrospectively evaluated. Frequency, clinical features, and management of toxic corneal ulcers are described. The relationship between clinical severity and outcomes (healing time, corneal transparency, and visual acuity) of toxic corneal ulcers and the number and classes of topical drugs, the number of daily instillations, and the duration of treatment were statistically evaluated.

RESULTS

Toxic corneal ulcer was diagnosed in 9% (21/226) of all patients. After topical treatment discontinuation, the cornea spontaneously healed in all patients in 2 to 21 days. A longer healing time was related to a greater number of topical drugs used (p=0.029), a greater frequency of daily instillations (p=0.042), and a longer duration of treatment (p=0.048). The specific drugs used did not significantly influence healing time. After resolution, 16 out of 21 patients showed corneal scarring and impairment of visual function. The severity of corneal haze was related to the number of drugs used (p=0.023), to the frequency of daily instillations (p=0.031), and to the healing time (p=0.008).

CONCLUSIONS

Toxic corneal ulcer is a frequent disease that can potentially lead to permanent visual impairment. A high-dose regimen is the major risk factor for corneal toxic ulcer development and poor visual outcomes.