Abstract
Purpose :
We investigate the capability of a high volumetric-resolution imaging modality, Gabor-Domain Optical Coherence Microscopy (GD-OCM) to identify key features in the structural modification of the cornea in three frequent diseases
Methods :
Host corneal buttons were excised during penetrating keratoplasty from patients with Fuchs' endothelial corneal dystrophy (FECD), type IIIA lattice corneal dystrophy (LCD) and keratoconus. These buttons were sutured onto cadaver corneal rims to preserve their shape, and mounted onto a corneal artificial chamber and pressurized with balanced salt solution (BSS) to a normal physiologic pressure under 20 mmHg. Corneas were then imaged using GD-OCM that combines the high sectioning capability of optical coherence tomography with the high lateral resolution of confocal microscopy. The system achieved high-contrast imaging with a field of view of 1 x 1 mm2 and volumetric cellular resolution of 2 μm across a thickness of up to 2 mm in tissue. For each cornea, the liquid lens based microscope with dynamic focusing was configured to capture the full depth of the cornea in a non-contact mode. BSS was used as a refractive index matching solution between the microscope and the cornea (~100 μm gap).
Results :
The imaging system produced 3D high resolution of the cornea over a 1 x 1 mm2 field of view as shown in Figure 1. Results showed high-contrast images of the different layers of the cornea, which revealed some keys features associated with each disease. For FECD: GD-OCM showed the thickening of the Descemet's membrane and stroma as well as the increase in density and size of keratocytes, along with associated guttae. Change in keratocytes appeared to start in the posterior stroma early in the disease process and moves toward the anterior stroma during the course of the disease. For LCD: lattice linear deposits were identified in the anterior stroma. Keratocytes and ECs were preserved. For keratoconus, folds were identified in the posterior stroma, presumably Vogt's striae. Keratocytes and endothelial cells morphology was preserved
Conclusions :
The novel imaging modality revealed key pathologic features of several important corneal diseases. The enhanced imaging capabilities of GD-OCM including imaging all the corneal layers across a large field of view can be applied toward studying corneal diseases
This is an abstract that was submitted for the 2016 ARVO Annual Meeting, held in Seattle, Wash., May 1-5, 2016.