Applanation Tonometry Using One Drop of an Anaesthetic-fluorescein Mixture.

THE Goldmann applanation tonometer (1954), as modified by Goldmann and Schmidt (1957), is becoming the standard instrument for measuring the intra-ocular pressure. The accepted method of preparing the eye for a pressure reading is to anaesthetize the cornea and then to stain the pre-corneal film with fluorescein (DukeElder, 1962). The disadvantage of this method is that it requires two manceuvres which are frequently carried out in the dark-room under inadequate illumination. This paper introduces a method of anaesthetizing the cornea and staining the precorneal film with fluorescein using one drop combining the two agents (Fenton, 1964). The problem was twofold. First, to find an anaesthetic which would mix with a fluorescein solution. Secondly, to ensure that the final concentration of the two constituents was adequate for their respective functions.