Introduction
The corneal layer of the eye is a transparent dome-shaped layer that covers the iris and pupil part of the eye. It plays vital roles, like letting the light pass through and reach the retina for image formation and keeping the refraction power in check. In case of any damage to the cornea because of an infection or an injury, the cornea might have scars, or the structure can get altered. Thus, the amount of light entering the corneal layer will be compromised, and the vision can get blurry or, in some cases, completely affected.
Several conditions can affect the cornea. Those conditions include:
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Herpes of the eye or ocular herpes.
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Herpes zoster or shingles.
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Fuchs dystrophy.
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Keratoconus.
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Map-dot fingerprint dystrophy.
What Is Keratitis?
Keratitis is an inflammatory condition of the corneal layer. It can be infectious keratitis or non-infectious keratitis. An injury causes non-infectious keratitis due to excessive use of contact lenses. Classic signs of keratitis are eye redness, eye pain, tearing eyes, blurred or decreased vision, sensitivity to light, and a feeling that something is present in the eyes (a foreign body sensation).
Keratitis can be diagnosed with a basic eye examination, slit lamp examination, etc. Treatment includes topical medications with an eye patch for non-infectious keratitis. For infectious keratitis, appropriate eye drops (antibacterial, antiviral, or antifungal), depending on the causative factor, will help.
What Is Ocular Herpes?
It is an eye infection caused by a group of herpes simplex viruses - 1 (HSV-1). The infection present in the body can spread to the eye, causing ocular herpes. In some people, it can also reoccur due to factors such as an infection, eye injury, stress, periods, overexposure to cold winds, or in patients undergoing chemotherapy (weak immune system). Common signs of ocular herpes include eye pain, redness and swelling of the eye, tearing eyes, blurred vision, and sensitivity to light (photophobia).
Generally, herpes simplex eye infection can be resolved in a week or two with proper medications. Antiviral eye drops or steroidal eye drops will help heal the condition. In case of severe infection, antiviral tablets are prescribed too. If ocular herpes is left untreated, the condition may cause corneal scarring, glaucoma, or even permanent blindness.
What Are Shingles?
Shingles or herpes zoster infection is a painful blistering condition affecting various body parts, including the eyes. It may affect the eye's cornea, resulting in a swollen corneal layer. In addition, a rash can be present over the eye. Other signs and symptoms include tearing eyes, extreme eye pain, blurred vision, photosensitivity, irritant eyes, etc.
If the condition is left untreated, it may result in postherpetic neuralgia, glaucoma, and permanent blindness. Treatment includes antiviral drugs like Acyclovir, Valacyclovir, and Famciclovir. To ease the swollen eyes, eye drops will be prescribed.
What Is Fuchs Dystrophy?
Fuchs dystrophy is characterized by the accumulation of fluid in the corneal layer of the eyes, resulting in a swollen cornea. The endothelial cells of the corneal layer will maintain the fluid balance. If the endothelial cells decrease in number, the fluid will start accumulating. Thus, this affected corneal layer will become thick and affect the vision greatly. It can either result in blurred vision or cloudy vision. Fuchs dystrophy will affect both eyes. It will affect people aged 30 to 40 more commonly, but the signs and symptoms will show up only in their 50s and 60s.
Some classic signs of Fuchs dystrophy include blurry vision, glare, painful blisters on the corneal surface, etc. Treatment includes 5% Sodium chloride eye drops and contact lenses in case of a mild condition. In severe cases, transplantation of the cornea will be required.
What Is Keratoconus?
The corneal layer of the eyes is generally dome-shaped. The cornea will protrude in certain cases, such as Down’s syndrome, retinitis pigmentosa, inflammatory conditions, etc., forming a cone shape. This occurs because the collagen layer in the corneal layers will not work properly to sustain the shape of the cornea. Classic signs of a keratoconus condition include double vision, blurred vision, halo vision being more common, ghost visuals, etc. Since the surface and shape of the cornea get damaged, mostly corneal transplantation will be suggested as a treatment choice. Another treatment includes cornea collagen crosslinking to prevent further damage from happening.
What Is Map-Dot Fingerprint Dystrophy?
It is a genetic disorder affecting the epithelial cells lining the corneal layer of the eyes. The unwanted epithelial cells will form a fingerprint-like structure resulting in corneal abrasions. Common signs and symptoms of map-dot fingerprint dystrophy are blurred vision and epithelial cell erosion, which can be painful. Diagnosis of this condition will include several tests like slit lamp examination and corneal topography.
In milder infections, the condition can be observed to resolve sometimes. If severe symptoms like epithelial cell erosion occur, the affected epithelial layer will be removed by a procedure known as superficial keratectomy. The affected epithelial layer will be removed using a diamond bur instrument, and a bandage will be applied to the site. The patient might feel uncomfortable for a few days but will heal sometime.
Conclusion
Infection or an injury affecting the eyes is a big issue though it heals on its own most of the time. But in some cases, it can become severe and damage the vision for life. So it is important to consult an eye specialist to diagnose and treat the condition at the earliest and to avoid complications.
