BACKGROUND: To compare intraocular pressure (IOP) measurements obtained with the digital tonometer TGDc-01 'PRA' with those from a Goldmann applanation tonometer (GAT). METHODS: The IOP in 176 eyes of 88 healthy volunteers was measured prospectively in a sitting position. One single measurement, generated by the TGDc-01 PRA, was compared with a single reading from the GAT. RESULTS: Mean IOP values were 13.0 +/- 3.7 mm Hg for the TGDc-01 PRA (range, 4-22 mm Hg) and 14.9 +/- 3.2 mm Hg for the GAT (range, 8-27 mm Hg). The mean difference was 1.9 mm Hg with a standard deviation of 2.77 mm Hg, and this was statistically significant (p < 0.001, paired t test). CONCLUSIONS: In comparison to the GAT, the TGDc-01 PRA underestimated IOP on an average of 1.9 mm Hg. Only 50.6% of all measurements were within the +/-2 mm Hg difference range. Thus, the TGDc-01 PRA has no high coincidence degree with the GAT. Both methods were not equivalent. Copyright (c) 2004 S Karger AG, Basel.
BACKGROUND: To compare intraocular pressure (IOP) measurements obtained with the digital tonometer TGDc-01 'PRA' with those from a Goldmann applanation tonometer (GAT). METHODS: The IOP in 176 eyes of 88 healthy volunteers was measured prospectively in a sitting position. One single measurement, generated by the TGDc-01 PRA, was compared with a single reading from the GAT. RESULTS: Mean IOP values were 13.0 +/- 3.7 mm Hg for the TGDc-01 PRA (range, 4-22 mm Hg) and 14.9 +/- 3.2 mm Hg for the GAT (range, 8-27 mm Hg). The mean difference was 1.9 mm Hg with a standard deviation of 2.77 mm Hg, and this was statistically significant (p < 0.001, paired t test). CONCLUSIONS: In comparison to the GAT, the TGDc-01 PRA underestimated IOP on an average of 1.9 mm Hg. Only 50.6% of all measurements were within the +/-2 mm Hg difference range. Thus, the TGDc-01 PRA has no high coincidence degree with the GAT. Both methods were not equivalent. Copyright (c) 2004 S Karger AG, Basel.