Abstract
Purpose:
Intraocular pressure (IOP) measurements taken during ophthalmologic examinations affect clinical decision-making. For example, IOP is an important factor in deciding whether or not to start, discontinue, or continue IOP-lowering agents. Gonioscopy (an examination of the drainage system of the eye) is a procedure performed commonly by ophthalmologists, especially in patients suspected or known to have glaucoma. To date, there are no published data regarding the potential effect of gonioscopy on IOP. The purpose of the current study is to investigate whether gonioscopy has an effect on IOP.
Methods:
The study protocol was approved by the Penn State College of Medicine Institutional Review Board. All study participants were recruited from the Penn State Hershey Eye Center glaucoma clinic. Participants were consented according to the IRB protocol. Baseline IOP of study participants was measured in each eye using Goldmann applanation. Gonioscopy was performed on participants’ study eye only. The study eye was determined by alternating between right and left eyes of consecutive study participants. At 1 and 5 minutes after gonioscopy completion, participants’ IOP was measured in each eye using Goldmann applanation. Participants’ fellow eyes, which did not undergo gonioscopy, served as control eyes. Change in IOP between the baseline and 1-minute measurements, and between the baseline and 5-minute measurements, were compared between study and control eyes.
Results:
The study included 18 participants. Nine (50%) were male. Average age was 71 (+13) years. There was no significant difference in central corneal thickness between the study and control eyes (552 and 553 microns, respectively). There was no significant difference in IOP between study and control eyes at baseline, 1 minute and 5 minutes. Both study and control eyes showed a significant decrease in IOP between baseline vs. 1 minute, and baseline vs. 5 minutes.
Conclusions:
Although both the study and the control eyes showed a significant downward trend in IOP with repeated measurements, there was no difference in the magnitude of IOP reduction between the study and control eyes. Thus, there does not appear to be a significant effect of gonioscopy on IOP measurement.
Keywords: 568 intraocular pressure •
420 anterior chamber •
427 aqueous