Cornea

The cornea is the front window of the eye, like the windshield of your car.  It is amazing that the body can produce tissue that is perfectly clear.  The shape of the cornea helps to bend and focus the light rays as they enter the eye.  There are three main layers to the cornea and different diseases can affect each layer.  The outer layer is the epithelium.  This thin layer of skin is so thin that it remains clear.  A corneal abrasion develops when this thin skin is scratched away from the cornea.  This can be very painful because there are hundreds of small nerves that are exposed when the epithelium is gone.

The stroma is the thickest part of the cornea (but is still very thin – only ½ of a millimeter).  This structure gives the cornea its amazing strength.  Injuries to the cornea lead to scarring which cause the tissue to become white and cloudy.  The only way to remove this scar is with a corneal transplant surgery.

The endothelium is the thin inner lining of the cornea.  This layer has a special function to pump fluid out of the stroma.  If these cells get damaged and lose their ability to pump, the cornea becomes swollen (called edema).  A swollen cornea also becomes white and cloudy and causes decreased vision.  To fix this condition a partial cornea transplant (DSEK procedure) surgery can be done to implant new healthy endothelial cells into the eye.

A laser can be used to change to shape of the cornea.  This can help you to see better without glasses or contact lenses (called refractive surgery).  The laser can be applied to the surface of the cornea (PRK – photo refractive keratomeilusis) or applied under a thin flap of stroma (LASIK – Laser assisted).

DSEK

DSEK is an amazing procedure developed to restore the clarity of the cornea when edema or swelling is causing loss of clarity.  Dr. DeBry was the first surgeon in Las Vegas to perform DSEK and has successfully treated numerous patients with DSEK, cornea transplantation, and other similar sight-saving procedures.

DSEK stands for Descemet Stripping Endothelial Keratoplasty, which is a complicated way of describing a partial cornea transplant surgery.  Before DSEK, the main treatment option for a scarred or swollen cornea was a regular cornea transplant (PKP or penetrating Keratoplasty).  This surgery has been used for decades to restore vision but has some weaknesses.  With a standard transplant there is a prolonged visual recovery, usually 12 months or more to achieve the best vision.  The eye is always weaker where the incisions are made, leading to a risk of severe vision loss with mild eye trauma.  And, the shape of the cornea is often irregular from the sutures.

DSEK overcomes many of these issues and is overall a much better procedure for certain corneal diseases.  The recovery time is much quicker, the eye does not have large incisions that weaken the cornea, and the shape of the cornea maintains a nice round shape.

DSEK is best for corneal diseases that lead to loss of endothelial cells and the edema or swelling that results.  If there are thick scars in the cornea a full cornea transplant is probably necessary.

DMEK

Patients with eye conditions such as Fuchs’ Dystrophy and corneal edema can now benefit from the most advanced corneal surgery in Las Vegas. The cornea is the clear front window of the eye and must be perfectly clear to enable perfect vision. The cornea is amazing! The entire structure is only ½ of a millimeter in thickness, less than 1/50th of an inch. When corneal endothelial cells become damaged through degeneration or previous eye surgeries, the cornea develops swelling (edema) and becomes cloudy. This swelling leads to foggy vision.

DSEK (Descemet-stripping Endothelial Keratoplasty) is a partial cornea transplant that replaces the damaged endothelial cells. This high technology procedure was developed over 10 years ago and has revolutionized corneal surgery for damaged endothelial cells. DSEK takes a section of the inner cornea less than the thickness of a human hair (1/10th of a millimeter or 5/1000th of an inch) from a person who died from an accident or medical condition and implants the new tissue into the eye. The DSEK graft contains the healthy endothelial cells and a section of the corneal stroma. DSEK has a very good track record of providing great surgical outcomes for patients with corneal conditions.

With the continued evolution of techniques an even better procedure has now been developed called DMEK (Descemet’s Membrane Endothelial Keratoplasty). DMEK is very similar to DSEK, but the tissue transplanted is only 10 microns thick (1/10th of the size of a human hair or 1/100th of a millimeter). This very thin tissue has several benefits including a faster recovery, better chance at achieving 20/20 vision, and a lower chance of rejection.

Dr. DeBry was the first surgeon in Las Vegas to perform DSEK and has treated hundreds of patients over the last 10 years. In 2016 he was again the first surgeon to bring new technology to patients in Las Vegas with the addition of DMEK. If you have a corneal condition requiring surgery, we invite you to meet with Dr. DeBry to see if DMEK or DSEK are the right procedures for you.

DMEK and Advantages over DSEK

  • Exact anatomical replacement of the diseased tissue
  • Better visual results
  • Faster visual recovery
  • Lower rejection rate

Las Vegas’ most experienced DMEK corneal surgeon, Peter W. DeBry, M.D.

DMEK Quick Facts

  • DMEK = Descemet’s Membrane Endothelial Keratoplasty
  • DMEK is a partial cornea transplant.
  • Descemet’s Membrane is the thin inner lining of the cornea.
  • Descemet’s Membrane holds the endothelial cells that are responsible for keeping the cornea clear.
  • When corneal endothelial cells get damaged from disease or past surgery, the cornea becomes swollen and cloudy.
  • With DMEK, the old and damaged endothelial cells are removed and new healthy cells transplanted.
  • The transplant is provided as a generous gift from an eye donor who recently died.
  • A gas bubble is put inside the eye to help the new cells stick into position on the cornea.
  • The typical recovery is usually 4-6 weeks.
  • The transplanted tissue is 1/10th the thickness of a human hair.

Fuchs’ Dystrophy

Fuchs’ Endothelial Dystrophy is a fairly common degenerative condition of the cornea.  Remember that the cornea is the clear front window of the eye like the windshield of your car.  The cornea has a thin layer of endothelial cells that cover the inner surface of the cornea.  These cells have the special job of pumping fluid out of the cornea.  This helps maintain the clarity of the cornea.  With Fuchs’ Dystrophy these cells degenerate slowly over time.  This can lead to a slight haziness to the vision.  When many cells are damaged the cornea becomes swollen (edema).  When the visual symptoms start to interfere with a patient’s daily activities a surgery is recommended.  The procedures that are the most beneficial for this condition are DSEK or DMEK.  These procedures implant new healthy cells into the cornea to replace the damaged cells.

Dr. DeBry has been taking care of patients with Fuchs’ Dystrophy in Henderson and Las Vegas for many years.  He was the first eye surgeon in Las Vegas to treat Fuchs’ Dystrophy with a partial corneal transplant procedure (DSEK).

 

For more information…

National Library of Medicine article on Fuchs’ Dystrophy

Cornea Research Foundation article on Fuchs’ Dystrophy