Abstract
Purpose::
To observe sequential changes in the morphological structures of cornea during intraocular pressure (IOP) alteration by full-field optical coherence tomography (OCT).
Methods::
Corneas in excised porcine eyes were used for the study. The samples were mounted on a Barron artificial anterior chamber, and the hydrostatic pressure of BSS Plus solution (at 37 degrees Celsius) was altered from 18 mmHg to 72 mmHg. A full-field optical coherence tomography system was employed, where the sample was illuminated with the probe beam and a horizontal cross-sectional image was detected using a CCD camera. To extract the interference component from the output of the CCD camera, a conventional phase-shift detection technique was used. The experimental setup offered a field of view of 420 µm x 420 µm and a 1.5 µm x 1.7 µm (longitudinal x transverse) resolution.
Results::
Differences between bright and dark cells in superficial corneal epithelial cells and contrast in intercellular lesion at wing cell and basal cell levels became prominent with high IOP. The changes of signal intensity (72 mmHg/ 18 mmHg) at wing cell, basal cell levels were about 61%, 46%, respectively. Higher signals of keratocyte and extra-cellular matrix at corneal stroma were also observed with high IOP than those of low IOP.
Conclusions::
With the full-field OCT used in the study, the changes in morphological structures of the cornea during intraocular pressure (IOP) rise can be monitored sequentially with non-invasive fashion.
Keywords: imaging methods (CT, FA, ICG, MRI, OCT, RTA, SLO, ultrasound) • imaging/image analysis: non-clinical • cornea: basic science