PURPOSE: To determine the efficacy of isopropyl alcohol 70% versus sodium hypo-chlorite in the disinfection of Goldmann tonometer prism in a clinical setting. DESIGN: Prospective, randomized, comparative clinical study. METHODS: Isopropyl alcohol 70% and sodium hypochlorite were compared to a control group in a total of eighty-one tonometer prisms used in different patients. MAIN OUTCOME MEASURES: Efficacy of isopropyl alcohol 70% and sodium hypo-chlorite in the disinfection of Goldmann tonometer prism. RESULTS: No statistical difference was found between isopropyl alcohol 70% and sodium hypochlorite in bacterial elimination (100%) compared to the control group. CONCLUSION: Results suggest that tonometer prism disinfection might not be necessary unless infection susceptibility factors such as corneal deformities and conjunctivitis or systemic infections are present.

Acanthamoeba keratitis is a sight-threatening corneal infection, which is rare, but may be increasing in frequency. The spectrum of disease ranges from mild, with an excellent prognosis, to severe and complicated with significantmorbidity. Its diagnosis is frequently delayed and the index of suspicion needs to be high, particularly in cases of atypical keratitis in contact lens wearers. Prolonged medical therapy with multiple anti-amoebal agents is usually required and penetrating keratoplasty is sometimes necessary for visual rehabilitatio.