Effect of Ultraviolet-A and Riboflavin treatment on the architecture of the center and periphery of normal rat cornea: 7 days post treatment.

Corneal collagen cross-linking (CXL) is a treatment that is widely applied to halt the progression of ectatic diseases such as keratoconus by creating biomechanical strength in the cornea. Most of the studies assessed the effect of the CXL on the cornea without any differentiation of its effect between periphery and the center of the untreated control cornea especially after the 7 days of CXL application. We investigate the ultrastructural changes in the architecture of the center and periphery of rat corneas, 7 days after standard CXL application.

A unique pre-endothelial layer at the posterior peripheral cornea: ultrastructural study.

This study was conducted to investigate the ultrastructure of a unique structures at the anterior side of the endothelium of the posterior peripheral cornea and compare their inner fibers to those of the limbus and sclera. The unique structures at the anterior side of endothelium was referred as a pre-endothelial (PENL) structures in the present manuscript. Ten anonymous-donor human corneoscleral rims (leftover after corneal transplants) were processed for electron microscopy.

Ultrastructural study of collagen fibrils, proteoglycans and lamellae of the cornea treated with iontophoresis - UVA cross-linking and hypotonic riboflavin solution.

To investigate the effects of iontophoresis-ultraviolet A (UVA) cross-linking (CXL) with hypotonic riboflavin solution on the ultrastructural changes in the lamellae, collagen fibrils (CFs), and proteoglycans (PGs) in the central and peripheral stroma of the human corneal buttons. The iontophoresis method was used for the -epithelial application of hypotonic riboflavin in corneal culture for 5 min. The corneas were irradiated using three methods: a UVA irradiance of 3 mW/cm for 30 min; a UVA irradiance of 10 mW/cm for 9 min; without UVA irradiation.

Collagen fibrils and proteoglycans of peripheral and central stroma of the keratoconus cornea - Ultrastructure and 3D transmission electron tomography.

Keratoconus (KC) is a progressive corneal disorder in which vision gradually deteriorates as a result of continuous conical protrusion and the consequent altered corneal curvature. While the majority of the literature focus on assessing the center of this diseased cornea, there is growing evidence of peripheral involvement in the disease process. Thus, we investigated the organization of collagen fibrils (CFs) and proteoglycans (PGs) in the periphery and center of KC corneal stroma.

Clinical and Ultrastructural Studies of Gelatinous Drop-Like Corneal Dystrophy (GDLD) of a Patient with 2 Gene Mutation.

Purpose: To describe clinical, molecular genetics, histopathologic and ultrastructural findings of gelatinous drop-like corneal dystrophy (GDLD) (OMIM #204870) in a Sudanese patient.

Method: An ocular examination revealed the onset of GDLD in a Sudanese patient (50 years old) at King Khalid Specialist Hospital, Riyadh. The 333 sequence variants in 13 GDLD genes of a DNA sample were screened by Asper Ophthalmics Ltd.

Ultrastructural study of peripheral and central stroma of keratoconus cornea.

Purpose: Assess the lamellar organisation of the peripheral and central stroma of the keratoconus (KC) and normal cornea.

Methods: Five normal and three KC corneas were fixed in 2.5% glutaraldehyde and processed for electron microscopy.