Intraocular pressure variation from ocular compression in low and high myopia

Abstract

Abstract Introduction Recent studies have monitored lamina cribrosa deformation using optical coherence tomography during ocular compression. Intraocular pressure (IOP) was measured only once immediately after ocular compression. This study aimed to evaluate IOP changes during and after ocular compression and compare the differences between low and high myopia. Methods Two groups of young, healthy adults were age-matched and underwent ocular compression. IOP was measured at baseline and monitored during a 2-min ocular compression followed by a 10-min recovery phase. Rebound tonometry was used and applied at 30-s intervals. Results Thirty low and 30 high myopes (60 right eyes) were included in the study. They had similar baseline IOP at 14.9mmHg. The immediate IOP rise was 10.2mmHg and 10.3mmHg from baseline in each group, respectively. Low myopes had faster IOP decay during ocular compression at -3.24mmHg/min than high myopes at -2.58mmHg/min (p = 0.0528). The IOP dropped below the baseline level after the release of the compressive force. Low myopes had IOP that returned to baseline levels faster (at 360 s) than high myopes (at 510 s). Conclusion Measuring IOP once immediately after ocular compression could under-estimate the effect of IOP increase on lamina cribrosa deformation. The difference in IOP dynamics from ocular compression between low and high myopia may be used to reflect aqueous humour outflow facilities.