Abstract
Purpose :
Measurement of intraocular pressure is an essential component of any ophthalmologic exam. Elevated intraocular pressure (IOP) is a common complication following pars plana vitrectomy. The purpose of this study was to compare intraocular pressure measurement using Goldmann applanation tonometry (GAT) with and without fluorescein strips, and with Tono-Pen XL Applantion Tonometer (TPA) for post-operative retina patients.
Methods :
This was a comparative clinical study performed at the Institute of Ophthalmology and Visual Science’s surgical retinal eye clinic. The study population consisted of 36 patients. IOP was first measured using a calibrated Tono-pen, then GAT IOP was measured without fluorescein, and then with fluorescein. The main outcome measure was IOP.
Results :
Measurements were obtained on a total of 64 eyes (36 right eyes and 28 left eyes) of 36 patients; 22 eyes had undergone previous PPV. Mean IOP measurements for the TPA, GAT without fluorescein, and GAT with fluorescein were 14.14±4.91, 14.70±5.41, and 15.84±5.38mmHg, respectively (Table1). Statistical analysis was performed using a two sample t-test. When GAT with fluorescein was compared with TPA and then with GAT without fluorescein, the mean difference was 1.70 (p=0.064) and 1.14 (p=0.234)mmHg, respectively. These differences were not found to be statistically significant although the mean difference between GAT with fluorescein and TPA came close to statistical significance (p=0.064). Statistical analysis was also performed using only the subset of eyes which had undergone PPV with similar results (Table 2). Furthermore when PPV eyes were sub grouped into post operative day 1 eyes versus post operative week 1 or greater eyes, again no statistical difference was found.
Conclusions :
Using GAT with fluorescein as the standard of comparison, these results indicated that there was no statistically significant difference between GAT with fluorescein and GAT without fluorescein. The results of this study suggest GAT with fluorescein and GAT without fluorescein may be used interchangeably in the clinical setting. Tono pen measurement is also an acceptable method of measurement, although clinicians should exercise more caution in patients requiring more precise IOP measurements such as those with glaucoma. Further larger studies may be needed in the future to elucidate differences between the various methods of IOP measurement.
This is an abstract that was submitted for the 2017 ARVO Annual Meeting, held in Baltimore, MD, May 7-11, 2017.