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Published on: June 20, 2015
Reliability of intraocular pressure by Tono-Pen XL over amniotic membrane patch in human
Tsuyoshi Yoshita1, Akira Kobayashi, Mami Takahashi
1Department of Ophthalmology, Kanazawa University Graduate School of Medical Science, Kanazawa, Japan.
Purpose:
To determine the reliability of Tono-Pen XL in measuring intraocular pressure (IOP) over the amniotic membrane patch in human eyes.
Method:
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 and without a single layer amniotic membrane (P = 0.808). Nor did we find any statistical difference between the IOP measured with and without double-layer amniotic membrane patch (P = 0.813). The average thickness of the single- and the double-layer amniotic membrane patch measured by pachymetry was 131.9 +/- 31.4 microm (mean +/- SD) and was 246.1 +/- 69.3 microm (mean +/- SD), respectively.
Conclusions:
This study showed that it is reliable to measure IOP by Tono-Pen XL over single or a double layer 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.

