Effects of disinfecting solutions recommended by the Centers for Disease Control on Goldmann tonometer biprisms

Twelve new Goldmann biprisms were used to measure the intraocular pressure of one eye of one subject, four times each day for 15 days. Between measurements, each biprism was disinfected by soaking in one of the three solutions recommended by the Centers for Disease Control (CDC) as effective against HIV, or by rubbing with an isopropyl alcohol swab. Intraocular pressure measurements, clarity of the biprism front surface, and ring image were statistically evaluated to determine whether any regimen negatively affected the biprisms. Biprisms soaked in alcohol were unusable after 4 days due to front surface roughness. No clinically significant differences were found in IOP measurements or clarity of the remaining groups, but the ring image was significantly less distorted with hydrogen peroxide treatment. These results suggest that hydrogen peroxide should be used to disinfect Goldmann biprisms.