Related Experiment Videos
Pneumotonometry versus Goldmann tonometry after laser in situ keratomileusis for myopia
1Department of Ophthalmology, Assaf Harofeh Medical Center, Zerifin, Israel.
Purpose:
To assess the reliability of intraocular pressure (IOP) measurement by Goldmann applanation tonometry (GAT) versus pneumotonometry in patients after laser in situ keratomileusis (LASIK) for myopia.
Setting:
Shiley Eye Center, University of California San Diego, La Jolla, California, USA.
Methods:
In this prospective study, 31 eyes of 17 patients were evaluated before and 1 month after having LASIK for myopia. A masked observer measured preoperative and postoperative IOP by GAT centrally and by pneumotonometry at the center and the periphery of the cornea. Central corneal thickness and curvature were evaluated.
Results:
Preoperative IOP showed a good correlation between GAT and pneumotonometry values (r = 0.82). Mean postoperative IOP by GAT was lower by 3.8 mm Hg +/- 2.2 (SD) (26.3% +/- 15.2%) than by pneumotonometry: 2.3 +/- 2.8 mm Hg (15.4% +/- 10.7%) (P = .01). There were no statistically significant differences in central IOP versus peripheral IOP measured by pneumotonometry (P = .4). Regression analysis showed no statistically significant differences in IOP as a function of change in corneal thickness or change in corneal curvature with either device.
Conclusion:
Postoperatively, there was a decrease in IOP measured by central GAT that was statstically significant. Differences in pneumotonometry were less substantial, with greater reliability of pneumotonometry than GAT after LASIK.