Human cornea is the anterior transparent layer of the eye globe. It is an avascular tissue that is directly exposed to the external environment. Cornea focuses the surrounding image by refracting the light through a crystalline lens to the retina. Therefore, its clarity should be well maintained for optimal visibility [1]. Cornea is a multilayered tissue and each layer has its own specificity. ...

Permeation of a drug through the cornea may be studied in vitro by using either the excised cornea of slaughtered animals or an organotypic cornea construct [1]. To compare drug permeability data reported in the literature for excised porcine cornea [2] with those from cornea constructs, the cultivation of an organotypic porcine cornea is required. The porcine cornea consists of three major cel...

PURPOSE The size and organization of stromal collagen fibrils influence the biomechanical and optical properties of the cornea and hence its function. How fibrillar structure varies with position across the cornea has not been fully characterized. The present study was designed to quantify the collagen fibril spacing and diameter across the normal human cornea and to relate this to the properti...

The decellularized cornea has received considerable attention for use as an artificial cornea. The decellularized cornea is free from cellular components and other immunogens, but maintains the integrity of the extracellular matrix. However, the ultrastructure of the decellularized cornea has yet to be demonstrated in detail. We investigated the influence of high hydrostatic pressure (HHP) on t...

PURPOSE To study the phenotypes, distribution, and morphologies of different antigen-presenting cells (APCs) in the murine cornea. METHODS Intravitreal injection of fluorescently tagged ovalbumin (OVA) or antibodies to MHC-II (I-A(d)), F4/80, CD11c, B7-1, and B7-2 was performed to label cells in the murine cornea. Light and transmission electron microscopy were used to examine corneal histolo...

The barrier characteristics of the cornea are interrogated using impact micro-particles into ex vivo porcine cornea. Using a commercial gene gun (BioRad; PDS1000), microparticles were accelerated and made to embed in target materials: either ballistic gelatin as reference or corneal tissue. Statistical analysis penetration polydisperse spherical (5–22 μm dia.) with density 2.5 g/cc, 4.2 7.8 g/c...

PURPOSE The biomechanical properties of the cornea have an important role in determining the shape of the cornea and visual acuity. Since the cornea is a nonhomogeneous tissue, it is thought that the elastic properties vary throughout the cornea. We aim to measure a map of corneal elasticity across the cornea. METHODS An acoustic radiation force elasticity microscope (ARFEM) was used to creat...

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. The ultrathin sections were observed under JEOL 1400 TEM, and digital images were taken with a bottom-mounted 11-megapixel Quamisa camera, using the iTEM softwa...

Topographic analysis systems used to analyse the cornea profile have some limitations due to the aspheric nature of the cornea. In many cases the cornea is modelled by a spherocylindrical surface. However the normal cornea is aspheric and flattened from the center to the periphery. Moreover diseased and postsurgical corneas rarely approximate a spherocylindrical surface. Topographic analysis sy...

There was a partial thickness laceration of the right cornea at the junction of the middle and lower thirds extending in an irregular horizontal line from side to side. From the depth of this laceration the cornea was split to the lower limbus and in the lamellar pocket so formed were embedded multiple fragments of a shattered corneal contact lens. At no point did this lamellar laceration penet...