Age-Related Macular Degeneration (ARMD) is a disorder where there is an anatomical and functional deterioration of the macula usually associated with an older age. The macula is the portion of the eye that provides us with fine and detailed vision. When we look directly at an object our macula is what fixates on it. Because of this, macular degeneration causes a loss of central vision. In Americans over the age of 65, ARMD is the leading cause of vision loss. As a larger portion of the population gets older it will become more and more prevalent.
There are “dry” and “wet” forms of macular degeneration. The “dry” form of macular degeneration happens because of non-vascular changes in the retina. The “wet” form of macular degeneration is because of neo-vascular (abnormal blood vessel growth) changes in the macula. About 85% to 90% of ARMD is the “dry” form. The “dry” form has no treatment, but specific vitamins may slow the progression. The “wet” form has treatment, but must be done quickly to avoid devastating vision loss.
Amblyopia Amblyopia or a “lazy eye” is where an eye is unable to see well at an older age even with the proper corrective lens and there is no disease as a cause. It is caused by visual deprivation to an eye during the early neurological development between the eye and visual cortex of the brain. During infancy and early childhood development, the visual cortex is forming neurological connections to the eyes. If an eye is not able to see well or properly at this time, a strong neurological connection is not formed or “hard-wired”. In other words, the brain will permanently “tune out” a bad eye because it is not getting a “clear reception” from it. Treatment involves removing the source of visual deprivation and patching of the non-amblyopic eye.
Blepharitis Blepharitis is inflammation of the eyelids. It is the result of bacteria on the eyelid margin or seborrheic dermatitis (excess oil production). The infection and excess oil production lead to inflammation, which causes irritation, dryness and redness. It is very common in the elderly and those with poor hygiene. Symptoms usually include scratchiness, itching, burning, foreign body sensation, and excess tearing. Crusty debris and flakes can be found on the eyelids around the eyelashes, especially upon waking. Sometimes the eyelids can even be stuck together upon waking. Treatment involves improving eyelid hygiene and sometimes antibiotics.
Cataracts are a clouding of the crystalline lens. The crystalline lens is located just behind the iris and helps to focus light on the retina. It is attached to the ciliary muscle by zonules.
There are three types of cataracts. They are nuclear sclerosis, posterior subcapsular and cortical cataracts. Nuclear sclerosis is a yellowing/browning of the nucleus of the crystalline lens that happens as we age. Posterior subcapsular cataracts develop on the backside of the crystalline lens underneath the exterior capsule. Cortical cataracts are cracks or spokes that happen in the cortex of the crystalline lens.
Colorblindness is better described as a color-deficiency because in the vast majority of people with the condition they can see colors, but lack the ability to perceive them the way most people do. By far most people with colorblindness have a red-green deficiency. When a colorblind person looks at a red apple, they will say it is red because they know it is red, but will perceive the actual color differently. It is an inherited trait that mainly affects men because it is an X-linked recessive gene. There is no treatment for the condition. However, a red contact lens can be used to help with detecting different hues. It may limit some in the career choices they make.
Conjunctivitis is an inflammation of the conjunctiva (the mucus membrane that covers the white colored part of the eye). Common signs and symptoms include redness, light sensitivity, foreign body sensation, itchiness and burning. It may be caused by numerous factors from a viral or bacterial infection, allergies, dry eye syndrome, or improper contact lens wear. Treatment ranges from artificial tears, cold compresses, removing the cause, medications and/or changing contact lens wearing habits.
A corneal ulcer is an erosion or open sore that has penetrated the cornea’s epithelial (skin) barrier. It usually appears as a white or gray lesion in the cornea. Symptoms include pain, light sensitivity, redness and decreased vision. Causes usually involve some type of breakdown of the epithelial layer that protects the cornea and the invasion of a pathogen. Your eye doctor will look at your cornea and eye very carefully with a biomicroscope. Treating a corneal ulcer usually begins with the frequent application of a topical antibiotic. Ulcers that are vision threatening, large or unresponsive to treatment should be cultured and referred to a corneal specialist promptly.
Diabetic Retinopathy Diabetes results from the body’s inability to properly manage the levels of glucose in the blood. It is caused by inadequate secretion of insulin or a poor response to it. Insulin secreted by the pancreas instructs the body to store glucose in the liver, muscles and fat tissue. Without glucose absorption, the level of glucose in the blood gets elevated. Elevated blood glucose causes damage to the vascular system. It causes problems to many parts of body, including the eye.
Diabetes may lead to decreased corneal sensation/healing, glaucoma, cataracts and most concerning retinopathy leading to blindness. Patients with diabetes may notice decreased/distorted vision and in some advanced cases blindness. Your eye doctor may notice hemorrhages, swelling and abnormal blood vessel growth in the retina. Regular dilated eye exams are important so that if treatment is needed, it can be initiated promptly. Treatment of diabetic retinopathy first involves getting the patient’s blood sugar under control. Advanced cases of diabetic retinopathy get treated by burning peripheral parts of the retina in a procedure called panretinal photocoagulation (PRP) and a vitrectomy.
Dry eye syndrome (DES) is a decreased quantity or quality of the eye's natural tears that leads to a drying out of the ocular surface. Symptoms include a foreign body sensation, scratchiness and burning. There are numerous causes of dry eye that include systemic diseases, hormone changes, medications, LASIK and the environment. Testing for dry eyes measures the amount of tear the eye secretes and assesses the quality of the tear film. Treatment includes the use of artificial tears, punctal plugs and the eye drop Restasis.
Floaters Floaters are typically strands of collagen fibers that exist in the vitreous or gel portion of the eye that move across the visual axis. They look like pieces of “wrinkled string” that seem to float in front of a person’s eyes. In most cases, they are harmless and only bothersome. When they are so numerous that they obstruct vision, they can be surgically removed through a procedure called a vitrectomy. If they occur with flashes of light or a loss of vision, an immediate visit to an eye doctor is required to check for a retinal detachment.
Glaucoma is a disease that first causes a loss of peripheral vision and in advanced cases causes a loss of central vision or blindness. The disease results from damage or destruction to ganglion cells. Ganglion cells have long axons or nerve fibers that carry the signal of photoreceptors inside the eye to an area of the brain where vision is processed. During an eye examination an eye doctor will see increased cupping or thinning of the rim of the optic nerve head as a result of nerve fiber loss. The exact cause of glaucoma is still undergoing much research and likely has many underlying risk factors. One major risk factor is an elevated intra-ocular pressure (IOP), however, having an elevated IOP does not mean that one has or will get glaucoma. The most effective treatment for glaucoma is lowering IOP.
Keratoconus is a progressive disease that results in an abnormal bulge or conical shape of the inferior cornea. The cornea is the clear front portion of the eye. The abnormal bulge may result in scattered and distorted light entering the eye, even with a good eyeglass prescription, causing poor vision. Soft contact lenses usually don’t correct well for advanced keratoconus because they conform to the shape of the cornea. This means that rigid gas permeable (RGP) lenses are used because they hold their smooth and proper shape over the cone resulting in better vision. Hybrid lenses are also available which have a hard center lens and a soft skirt. In advanced cases of keratoconus surgery and contact lenses may be required to provide adequate vision.
Keratoconus may occur in one or both eyes and frequently begins during an individual’s teens or early 20s. It may progress through middle-age (35-40 years old).
Papilledema is a swelling of the optic nerve head caused by elevated intracranial hypertension. Symptoms include headaches, nausea and visual field loss. Your eye doctor will notice elevated and blurred optic nerve head margins. Blood vessels coming from the optic nerve are also engorged. The most common causes of papilledema include brain tumors, poor absorption of the cerebral spinal fluid or medications. Treatment consists of managing a tumor if present, diuretics, losing weight and removal of any causative medications
A pterygium or “surfer’s eye” is an overgrowth of tissue that grows from the conjunctiva onto the cornea. It is the result of tissue that degenerates from exposure to ultraviolet light and the elements. Most often it is has a triangular shape and is very vascularized. They are mostly cosmetic and only need to be monitored for growth or any impact on vision. When significant, they induce mild to large amounts of astigmatism. If they grow over the visual axis, there can be loss of best corrected visual acuity. Treatment consists of UV protection, ocular lubrication and surgical removal. Even with removal re-growth can occur.
Retinal Detachment A retinal detachment is a very serious condition where the sensory layer inside of the eye called the retina tears and separates from the eye. If it is not treated promptly, permanent vision loss or blindness can occur. Symptoms of a retinal detachment include flashes of light, loss of vision and numerous new floaters. Causes of a retinal detachment include ocular trauma or surgery, high amounts of myopia, vitreous traction (jelly like portion of the eye pulling on the retina) and conditions that cause abnormal bleeding in the eye. To assess for a retinal detachment the eyes need to be dilated and then a thorough look at all parts of the retina needs to be done. Treatment involves injecting a gas bubble in the eye forcing the attached retina in place or suturing a sponge to the white portion of the eye that prevents further traction from the vitreous. Lasers or freezing are sometimes used to scar areas of the retina to prevent a detachment or limit further detachment.
Strabismus is a misalignment of the eyes, meaning that they don’t look at an object together. An eye can turn in, out, up or down. A long standing strabismus may not have any symptoms because the brain shuts off the image from the eye that turns out. A new onset results in double vision and disorientation. Strabismus occurs because of poor coordination between the extra-ocular muscles or the nerves that innervate them. Testing done by your eye doctor includes a cover test to assess ocular alignment, determination of refractive state and an assessment of ocular health. Treatment involves the use of prism in glasses, vision therapy, surgery and correction of refractive error.
A stye is an infection of an oil gland on the eyelid margin. It is also called a hordeolum. They usually present as a painful, red lump on the eyelid margin. They are frequently associated with blepharitis. Staphylococcal bacteria are the most common organism to cause the infection. In many cases they resolve on their own. Treatment consists of a warm compress to loosen inflammatory material and to open up pores. Lid scrubs with baby shampoo and water are important to clear the eyelid margin of bacteria. Without resolution oral antibiotics should be given. In some cases the stye may require drainage.