The cornea plays a critical role in facilitating vision by allowing light to enter the eye. If damaged, it can lead to blindness.

Transplantation of a healthy cornea is the traditional method used to restore vision, but it has limitations such as inadequate donor corneas, risk of rejection, and long-term complications. Partial corneal transplantation has emerged as an alternative method that has shown promising results in treating corneal damage. This article explores the recent advances in partial transplant techniques for corneal repair.

Lamellar Keratoplasty

Lamellar keratoplasty (LK) is a partial corneal transplantation procedure that involves removing the damaged or diseased portion of the cornea and replacing it with a donor cornea that is healthy. There are two types of LK: anterior and posterior.

Anterior LK involves replacing the front portion of the cornea, while Posterior LK involves replacing the back portion of the cornea. LK techniques have gained popularity because they offer faster visual recovery, minimal risk of rejection, and reduced risk of infections compared to full corneal transplants.

Descemet Stripping Automated Endothelial Keratoplasty

Descemet stripping automated endothelial keratoplasty (DSAEK) is a type of partial transplantation surgery that aims at replacing only the damaged endothelial layer of the cornea.

Endothelial cells are responsible for pumping excess fluid from the cornea, which keeps it clear. When they get damaged, the cornea can swell and start to blur vision. DSAEK involves removing the endothelial layer of the damaged cornea and replacing it with a donor endothelial layer.

DSAEK is less invasive than full corneal transplantation and offers faster visual recovery.

Descemet Membrane Endothelial Keratoplasty

Descemet Membrane Endothelial Keratoplasty (DMEK) is a more advanced partial transplantation procedure that aims at replacing only the damaged Descemet membrane and endothelial layer of the cornea.

The Descemet membrane is a thin layer of the cornea that separates the endothelial layer from the stroma. DMEK involves removing the Descemet membrane and replacing it with a donor Descemet membrane and endothelial layer. DMEK has been shown to offer better visual outcomes with fewer side effects compared to DSAEK and full corneal transplantation.

Deep Anterior Lamellar Keratoplasty

Deep Anterior Lamellar Keratoplasty (DALK) is a partial transplantation procedure that involves removing the damaged or diseased stromal layer of the cornea and replacing it with a donor stromal layer while leaving the Descemet membrane and endothelial layer intact. This technique is useful in treating corneal scarring and keratoconus, a condition where the cornea bulges outward. DALK is less invasive than full corneal transplantation and offers better visual outcomes.

Corneal Inlays

Corneal Inlays are a type of partial corneal transplantation procedure that involves placing a tiny lens-like device on the cornea’s surface to improve vision.

Corneal inlays are made of different materials, including hydrogel, acrylic, and silicone. They work by bending incoming light rays to improve focus on the retina, and they are used mainly to treat presbyopia, a condition that affects near vision.

Xenotransplantation

Xenotransplantation involves the transplantation of corneas from other species, usually pigs. Pig corneas have similar size and shape as the human cornea, and they are believed to have potential for use in treating corneal blindness.

Pig corneas have been successfully transplanted into human eyes, but the risk of infection and rejection is still relatively high, and more research is ongoing to explore the safety and effectiveness of this technique.

Conclusion

Partial corneal transplantation techniques have emerged as promising alternatives to full corneal transplantation. They offer faster visual recovery, minimal risk of rejection, and reduced risk of infections compared to full corneal transplants.

These techniques have shown promising results in treating a range of corneal conditions such as scarring, keratoconus, and endothelial cell damage. However, more studies are needed to explore their long-term safety and effectiveness.