Reliability of Intraocular Pressure by Tono–Pen XL over Amniotic Membrane Patch in Human

Abstract

Abstract: : Purpose: To determine the reliability of Tono–Pen XL in measuring intraocular pressure (IOP) over amniotic membrane patches in human eyes. Methods: Ten healthy volunteers (nine males and one female) participated in this study. After topical anesthesia, IOP was measured using the Tono–Pen XL before and after the application of a single layer amniotic membrane patch in the right eye and double layer amniotic membrane patch in the left eye. Results: We found no statistical difference between the IOP measured with (13.5±2.2 mmHg) and without (13.5±1.7 mmHg) a single layer amniotic membrane (P=0.808). Nor did we find any statistical difference between the IOP measured with (12.5±2.6 mmHg) and without (12.6±2.2 mmHg) double layers amniotic membrane patch (P=0.813). The average thickness of the single and the double layer amniotic membrane patches measured by pachymetry was 131.9±31.4 µm (mean±SD) and was 246.1±69.3 µm (mean±SD), respectively. Conclusions: This study showed that it is reliable to measure IOP by Tono–Pen XL over single or double layers of amniotic membrane patch on healthy human eyes. Further studies are required to determine the accuracy of IOP measurement over amniotic membrane patch on diseased corneas.

Keywords: cornea: clinical science • intraocular pressure • cornea: stroma and keratocytes