Prevention Of Infectious Keratitis After The Extraction Of A Metallic Corneal Foreign Body

The purpose of our trial was to analyze the risk of developing infectious keratitis after the extraction of a metallic corneal foreign body, using two different prophylaxis strategies. We compared the use of topical antibiotic prophylaxis with ciprofloxacin, against the use of anti-infective prophylaxis with Ozonest®️ (ophthalmic solution of ozonated oil in liposomes). 

Ophthalmology Department of El Bierzo Hospital, Ponferrada (Leon), Spain. The study was carried out according to the principles of the Declaration of Helsinki and the Good Clinical Practice Guidelines, and with the authorization of the Hospital's Ethics Committee. Prior informed consent was obtained from all study participants.

We performed a randomised control trial (low grade of intervention). Patients included were those who attended the emergency room and were diagnosed of metallic corneal foreign body acquired cutting metal with a radial blade. Twenty-eight patients were included and divided into two groups (after foreign body extraction). One group was treated with ciprofloxacin plus artificial tears 4 times a day, and the other was treated with Ozonest® plus artificial tears 4 times a day. The extraction of the foreign body was performed with a 27G needle and the affected corneal area was cleaned with an ophthalmic bur. After 48 hours patients were checked for reepitelization, absence of infection and Ozonest® tolerance.

The average size of the epithelial defects was 1.29 mm in the “Ozonest” group and 1.43 mm in the “Ciprofloxacine” group, with statistically non-significant differences (t=0.5; p=0.6). The probability of re-epitelization of the defect was 92.85% in the “Ozonest” group compared to 100% in the “Ciprofloxacine” group, with statistically non-significant differences (Chi2=1.037; p=1.00). In neither group was found evidence of epithelial defect infection. In both groups, all patients experienced improvement in signs and symptoms with treatment. Regarding tolerance when instilling Ozonest®, 57.14% experienced mild discomfort and 42.86% experienced no discomfort.

After corneal foreign body extraction, a residual epithelial defect remains in the cornea, which is a risk factor for infectious keratitis development. Anti-infective prophylactic treatment with topical antibiotics is required according to current guidelines. It is known that the wide use of topical antibiotic eye drops leads to increasing the risk of antimicrobial resistance rates. The development of alternative antiseptic molecules could be a solution in the anti-infective prophylaxis. The results of our study suggest that in both groups the prevention of infection was achieved, but studies with larger sample size are needed to draw definite conclusions and confirm that the use of Ozonest® could be a valid alternative.