Eye disorders

Anatomy of the Eye

• Cornea: clear tissue in the very front of the eye
• Iris: colored part of the eye surrounding the pupil
• Pupil: dark hole in the iris that regulates the amount of light going into the eye
• Lens: small clear disk inside the eye that focuses light rays onto the retina
• Retina: layer that lines the back of the eye, senses light, and creates electrical impulses that travel through the optic nerve to the brain
• Macula: small central area in the retina that allows us to see fine details clearly
• Optic nerve: connects the eye to the brain and carries the electrical impulses formed by the retina to the visual cortex of the brain

Here follows a short description of different eye disorders (ailments).

Age-Related Macular Degeneration (AMD)

Age-related macular degeneration is an eye disease that can start at any age, but it usually develops after the age of 60. This eye condition progressively breaks down your macula, which is the central portion of the retina. It rarely causes total blindness as only the central vision is affected.

There are two types of AMD: wet and dry. In wet macular degeneration, abnormal blood vessels behind the retina start to grow; leaking blood and fluid, causing loss of central vision and may occur quickly. In dry macular degeneration, the light-sensitive cells in the macula slowly break down causing central vision to diminish over time.

Cataracts

A cataract is a painless, cloudy lens in the eye that causes blurry vision and is one of the most common eye conditions among seniors. Cataracts can cause vision loss and progress slowly as we age.

Most people who reach their mid-70s will have some cataract-like changes to their lenses. Other than aging, causes of cataracts include diabetes, trauma, some medications, and excessive UV light exposure.

Your Optometrist can see a cataract while doing a routine eye examination. Treatments for cataracts include glasses, magnifying lenses, and surgery. Surgery is curative as the cloudy lens is removed and replaced with an artificial intra-ocular lens.

Glaucoma

Glaucoma refers to a group of eye diseases that cause pressure increases within your eye. The increased pressure affects the optic nerve and may cause vision loss. Glaucoma can be classified into two main types. These are open-angle, which is more common and develops more slowly, and angle-closure, which comes on suddenly and is painful. Without treatment, either type can cause vision problems and blindness.

In the early phases of glaucoma there are often no symptoms. By the time vision is affected, the damage is permanent. Progression of glaucoma can be slowed or halted with eye drops, laser treatments, or surgery. Early diagnosis is key.

People with a family history of glaucoma and the elderly are at increased risk of the disease.

Eye Allergies

Severe eye allergies may cause damage to the eye that may threaten eyesight. Allergies can cause chronic inflammation that may permanently damage the cornea. Causes of eye allergies are usually due to seasonal allergies, sensitivities to cosmetics or medications, or dust. Over-the-counter eye drops that contain antihistamines are usually helpful.

Keratoconus

The cornea is the clear surface covering the front of the eye. It is normally smooth and round, following the contour of the eyeball. Weakness in the structure of the cornea can lead to pressure in the eyeball, causing an conical-shaped abnormal bulge to the front of the eye in a condition called Keratoconus. Changes in the shape of the cornea make it difficult for the eye to focus even with the help of glasses or contact lenses. Keratoconus can also cause complications during certain eye surgeries. Treatment includes rigid contact lenses or corneal transplantation.

Retinal Detachment

Retinal detachment occurs when the retina (tissue in the back of the eye) separates (detaches) from its underlying structures. The build-up of fluid behind the retina is what separates the retina from the back of the eye. Retinal detachments are often painless, and symptoms that may be noticed include perception of flashing lights, floaters, or loss of visual field. Risk factors for retinal detachments include a nearsighted adult age 25 to 50 or an elderly person after cataract surgery. Treatment for a detached retina involves surgery, mostly using lasers, which can improve vision affected by the retinal detachment.

Diabetic Retinopathy

People with diabetes can have an eye disease called diabetic retinopathy. This is when high blood sugar levels cause damage to blood vessels in the retina. These blood vessels can swell and leak. Or they can close, stopping blood from passing through. Sometimes abnormal, new blood vessels grow on the retina. All of these changes can steal your vision. With NPDR, tiny blood vessels leak, making the retina swell. When the macula swells, it is called macular edema. This is the most common reason why people with diabetes lose their vision. Also with NPDR, blood vessels in the retina can close off. This is called macular ischemia. When that happens, blood cannot reach the macula. Sometimes tiny particles called exudates can form in the retina. These can affect your vision too. If you have NPDR, your vision will be blurry.

PDR is the more advanced stage of diabetic eye disease. It happens when the retina starts growing new blood vessels. This is called neovascularization. These fragile new vessels often bleed into the vitreous. If they only bleed a little, you might see a few dark floaters. If they bleed a lot, it might block all vision. These new blood vessels can form scar tissue. Scar tissue can cause problems with the macula or lead to a detached retina. PDR is very serious, and can steal both your central and peripheral (side) vision.

CLICK HERE for more information: Common Eye Disorders and Diseases

.