Cornea Specialists - Hershey, PA

What is Eye Disease Ophthalmology (Corneal and External Diseases)?

Corneal and external diseases are eye conditions that impact eye health by causing damage to the ocular (eye) surface. The cornea is a transparent layer that surrounds the exterior of the eye and protects it from scratches. It plays a critical function in vision by focusing light and filtering UV rays. Although the causes of corneal and external diseases are not always identifiable, frequent causes include injury and trauma, allergic reactions, infection, and hereditary conditions. Some of these diseases are easily treated (such as conjunctivitis) with minimal symptoms. Severe eye diseases, however, may require surgery and can cause pain, inflammation, and impaired vision. Fortunately, eye disease ophthalmologists can treat even severely damaged corneas using a variety of advanced surgical techniques.

Ophthalmologists may diagnose patients for corneal and external diseases through an eye exam which assesses patients' vision and any abnormalities of the surface and inner structure of their eyes. Other diagnostic evaluations may specifically examine the cornea, such as keratometry (cornea curvature test) and pachymetry (cornea thickness test). Blood tests may be useful to detect infection. Corneal and external diseases can include:

Conjunctivitis (pink eye) and blepharitis (eyelid inflammation)
Keratoconus, where the cornea begins to bend and lose its normal curvature
Corneal dystrophies, where genetic corneal conditions affect vision
Corneal infections such as herpes keratitis and acanthamoeba keratitis
Allergies and dry eye, where a decrease of natural eye tears dries the eyes
Epiphora, where excess natural eye tears cause watery eyes
Injury, where the cornea may tear
Pterygium (surfer's eye), where sun damage causes spots of growth on the cornea

For conjunctivitis, allergies, and minor infections, a patient may be prescribed antibacterial or antifungal eye drops, topical eye ointments, or antihistamine allergy eye drops. Other patients may require complex treatments such as:

Corneal transplants, where a damaged cornea is partially or fully replaced with a donated human cornea
Corneal inlays, where artificial implants are placed within the cornea
Corneal cross-linking, where ultraviolet light and special eye drops strengthen the cornea by triggering new collagen fibers (cross links)
Corneal lesion excision, where growths on the cornea are surgically removed

Ophthalmologists who treat corneal and external disorders are doctors who complete specialized corneal and external eye structure training. They may collaborate with optometrists, opticians, and other specialists.