Comparison of standard and computerized tonography instruments on human eyes

We compared the outflow facility coefficient results after indentation tonography obtained with a standard tonography unit and with a new computerized tonography machine. Goldmann applanation tonometry was followed by standard tonography on one eye and computerized tonography on the other. After a one-hour equilibration period, tonometry was repeated and followed by tonography with the testing units used on the opposite eyes. In nine of 60 eyes the results were discarded because of poor tracings or high error. Results of initial indentation intraocular pressure measured by the two units were not statistically different from those measured by Goldmann applanation tonometry. Mean outflow facilities determined by the standard unit and by the computerized machine with the average scleral rigidity program showed no statistically significant difference by the paired t-test.