Dr. John B. Cox and Dr. Heather Estopinal

Corneal Abrasion

The cornea is the clear front window of the eye. It covers the iris (the colored portion of the eye) and the round pupil. The cornea is composed of five layers. The outermost layer is called the epithelium.

Injuries to the epithelium, such as scratches, cuts, or scrapes, are known as corneal abrasions. Usually, these injuries are caused by fingernail scratches, makeup brushes, paper cuts, or rubbing of the eyes. Sometimes conditions like dry eye can cause abrasions. Symptoms associated with corneal abrasions include tearing, redness, pain, soreness, and blurred vision.

Treatment options for corneal abrasions include patching the injured eye, dilating pupils to relieve pain, wearing special contact lenses that promote healing, taking antibiotics to prevent infection, and using lubricating eye drops.

Minor abrasions usually heal within a day or two, while larger abrasions take about a week.

 

Corneal Erosion

Corneal erosion is caused by a loose attachment of the epithelium to the underlying tissue. This often happens at the site of an earlier abrasion. Some patients have an underlying condition called “map-dot-fingerprint dystrophy” that predisposes them to having recurrent corneal erosions.

Symptoms of corneal erosion are similar to those of abrasions: pain, soreness, redness, and blurred vision.

Treatment is the same as for corneal abrasion and may also include saline solution eye drops or ointments. However, if the erosion keeps occurring, further treatment may be necessary. These treatments may include procedures to remove the damaged epithelium, removal of corneal cells using a laser, or performing an anterior stromal puncture, which involves making tiny holes on the surface of the cornea to promote stronger attachments between the top layer of corneal cells and the layer of the cornea underneath.

Fuchs’ Dystrophy

Fuchs’ dystrophy is a progressive disease that affects the cornea, the clear dome that covers the iris (the colored part of the eye) and helps focus light as it enters the eye.

With this disease, cells in the cornea’s inner layer, called the endothelium, are reduced in number. This causes the remaining cells to swell or thicken. The loss of endothelial cells can also allow abnormal dewdrop-shaped growths called guttata to form.

These cell changes may cause the cornea to become cloudy and swollen. Because Fuchs’ dystrophy is a progressive disease, the changes to the cornea can interfere with vision over time. Fuchs’ dystrophy usually occurs in people after age 40. Studies show that it is an inherited condition.

Symptoms of Fuchs’ dystrophy include hazy or cloudy vision that develops in stages. In the first stage, as the cornea swells, vision in the morning may be hazy, but it clears up during the day. Once the disease has progressed to a more advanced stage, vision no longer clears, and instead, you may experience pain and sensitivity to light.

It can take up to 20 years or longer for Fuchs’ dystrophy to progress from its earliest stage to a stage that is visually or physically significant. To diagnose and monitor this condition, an ophthalmologist (Eye M.D.) checks for adequate endothelial cell number and function, may obtain an endothelial cell count, and may measure the thickness of the cornea.

In its early stage, Fuchs’ dystrophy is treated with saline eye drops to pull excess fluid from the cornea or by using a hairdryer to help dry the surface of the cornea. As Fuchs’ dystrophy advances, you may be given a therapeutic bandage contact lens to lessen your discomfort.

If vision loss begins to interfere with your life in the latter stages of the disease, a surgical procedure may be recommended.  These include a corneal transplant technique known as a penetrating keratoplasty, or an endothelial cell transplant known as a DSEK.

Keratoconus

Keratoconus is an uncommon condition in which the dome-shaped cornea (the clear front window of the eye) becomes thin and develops a cone-like bulge. As the condition progresses, the shape of the cornea is altered, distorting your vision. Usually, keratoconus affects both eyes, although symptoms and progression in each eye may differ.

Early symptoms include mild blurring of vision, increased sensitivity to light and glare, and mild eye irritation. The rate of progression varies. Keratoconus usually begins in the teenage years. It may progress slowly for 10 to 20 years and then suddenly stop. As it progresses, the most common symptoms are increased blurring, increased nearsightedness or astigmatism, inability to wear contact lenses, and frequent eyeglass prescription changes.

The causes of keratoconus are not known. Since an estimated 10% of people with keratoconus have a family member with the condition, some researchers believe genetics may play a role.

Keratoconus is usually corrected with eyeglasses. However, as the condition progresses, rigid contact lenses may be needed so that vision is improved. If vision is greatly affected, a corneal transplant may be recommended. While this procedure will relieve the symptoms of keratoconus, it will not cure it completely. Nonetheless, corneal transplants offer the best prognosis for clear vision.

Newer techniques have recently been evaluated to treat progressive keratoconus.  These techniques include stromal implants, corneal crosslinking, and others which are under investigation.     These have been shown to be effective in some patients. You should discuss this technology with your ophthalmologist (Eye M.D.).