Tonometry, the most important examination in the diagnosis of glaucoma, ought to be a perfectly safe one. Even a carefully performed tonometry sometimes results in minor abrasions of the corneal epithelium because of movements of the patient's eye or the tonometer, and keratitis may result in virulent micro-organisms from the tonometer are introduced into the corneal wound.
It is an established principle in ophthalmology that all solutions and instruments used by the eye surgeon on the patient's eye should be sterile, but most ophthalmologists sterilize their tonometers only rarely. Some ophthalmologists who have been lucky enough to avoid tonometer infections for years may consider regular sterilization of this instrument an unnecessary precaution, a waste of time.
The risk of nonsterile eye droppers is now generally recognized, but it is difficult to understand that more attention has not been paid to the sterility of tonometers.
No micro-organisms can grow on the
DREISLER KK. Sterilization of Jonometers. AMA Arch Ophthalmol. 1955;53(6):860-864. doi:10.1001/archopht.1955.00930010868013