Keratitis

Keratitis is a state during which the eye's cornea is inflamed. In Superficial keratitis, the superficial layers of the cornea are involved. In this type, a scar is not left after healing. In Deep keratitis, the deeper layers of the cornea are concerned. A scar is left after healing due to which the vision is impaired if it is on or near the visual axis.

Types of Keratitis

• Viral keratitis is of two types – Herpes simplex keratitis and Herpes zoster keratitis. Viral infection of the cornea is caused by the herpes simplex virus that results in 'dendritic ulcer'.
• Amoebic keratitis is the amoebic infection of the cornea that usually affects soft contact lens wearers. The cause is Acanthamoeba.
• Bacterial keratitis is due to an injury or due to wearing contact lenses. Staphylococcus aureus and Pseudomonas aeruginosa are the bacteria involved.
• Photokeratitis are due to intense ultraviolet radiation exposure like snow blindness or welder's arc eye.
• Ulcerative keratitis
• Contact lens acute red eye is a non-ulcerative sterile keratitis concerned with colonization of gram-negative bacteria on contact lenses
• severe allergic response may cause corneal inflammation and ulceration

Symptoms

• light sensitivity
• blurred vision
• pain
• redness
• discharge

Diagnosis
The healthcare professional will enquire about the symptoms, the vision and the health in general. A history of immune problems like chickenpox or shingles or arthritis may assist the doctor to diagnose keratitis. The eye specialist uses a device that magnifies the surface of the cornea to detect a tiny ulcer caused by viral infection. The ulcer sends out starlike branches and is well seen after a dye is used to stain the cornea for some period of time. Herpes simplex infection of the cornea also has the infection of the eyelid. Tiny, painful blisters that resemble cold sores of the lips are seen on the eyelid. The diagnosis also involves:

• testing the visual sharpness and clearness (visual acuity)
• testing how the pupil responds to light
• measuring the cornea
• examining the eye by using a special instrument called as a slit lamp
• swabbing the eye or taking samples from it to ascertain the diagnosis of herpes simplex infection

Treatment
Antiviral, antifungal and antibiotics medication is used to treat the apt organism. After the lab analysis determines the offending organism, the medication might be altered. At times multiple medication may be necessary. A sterile, cotton-tipped applicator might be used to slowly remove infected tissue and enable the eye to heal at a rapid rate. Laser surgery is employed to annihilate the unhealthy cells. Severe infections are in need of corneal transplants. Inappropriate prescriptions or over-the-counter preparations make the symptoms more severe and lead to tissue deterioration. Topical corticosteroids cause more harm to the cornea in patient's having this disease. A patient may wear a patch to protect the healing eye from bright light, foreign objects, other irritants and the lid rubbing against the cornea. The infection can lead to:

• glaucoma
• blindness
• ulceration of the cornea
• permanent scarring

The specific treatment is decided by the physician on the basis of:

• the child's age, general health and medical history
• expectations regarding the course of the disease
• the child's tolerance for specific medication's, procedures or therapies

Prevention
Individuals wearing contact lenses have to use sterile lens-cleaning and disinfecting solutions. As tap water is not sterile it cannot be used for cleaning contact lenses. Follow-up checkups are crucial as small defects of the cornea can develop and the patient may not be aware of it. Use of the contact lenses should not be overdone. In case the eyes become red or irritated, these have to be removed. As per schedule, replace the contact lenses. Due to proteins, there can be a deposit on the contact lenses and this may cause an increased risk of infection. The contact lenses have to be rinsed every night and dry them in the air. A well-balanced diet has to be ingested and protective glasses must be worn while working or playing in risky conditions. Goggles or sunglasses having ultraviolet coatings can assist in protecting against damage from ultraviolet light.