The retina is the light sensitive tissue at the back of the eye that acts as “the film in the camera”. It converts light into nerve signals that are transmitted along the optic nerve to the vision centers in the brain. Problems with the retina are a common cause for failing vision, especially in the elderly.
Diabetes is one of the leading causes of blindness in the United States. Leaking and bleeding blood vessels on the retina can cause severe visual loss. Effective treatments include laser photocoagulation, vitrectomy surgery and certain medications. Regular eye exams good medical management of blood sugar and blood pressure along with timely treatment can significantly reduce the risk of visual loss and blindness.
Macular Degeneration is the leading cause of blindness in the United States in persons over 60 years of age. While this condition rarely leads to total blindness, patients affected develop blurred, distorted, or patchy vision and may lose the ability to read, drive, or discern fine detail. Risk factors include nearsightedness, aging, heredity, and poor nutrition. Some macular degeneration cases may be treated with medication, laser or surgery.
Much like the film in a camera, the retina is responsible for creating the images one sees. When the retina detaches, it separates from the back wall of the eye and is removed from its blood supply and source of nutrition. If it remains detached, the retina will degenerate and lose its ability to function. Trauma, nearsightedness, proliferative diabetic retinopathy, and retinal tears are all causes of retinal detachment. Symptoms often include flashes of light, new onset of floaters, and loss of peripheral vision. If a retinal tear is discovered, detachment can usually be prevented using laser treatment. Fortunately, over 90% of retinal detachments can be repaired with a single procedure. The scleral buckle procedure, vitrectomy, and pneumatic retinopexy are three different surgical approaches for treating this condition. If you are diagnosed with retinal detachment, Dr. Leonard will discuss which option best suits you.
Floaters & Flashes
Flashing lights and floaters at the corner of the eye are a common occurrence for aging adults. Flashes and floaters can be benign and relatively harmless, or they can herald a significant pathological process in the back of the eye, which left unchecked can lead to loss of vision or major surgery. The only way to know if flashing light or floaters in your field of vision are benign or significant is to have Dr. Leonard dilate your eyes and examine them thoroughly.
The center of the eye is filled with a transparent gel like substance called the vitreous. As we age, the vitreous undergoes certain chemical changes. This leads to the formation of deposits of proteins which form clumps and strings floating in the gel. When light passes through the eye, the protein clumps throw a shadow on the retina producing a sensation of “floaters”.
Floaters may be seen as strings, streaks, clouds, bugs, dots, dust, or spider webs. These objects appear to be in front of the eye, but they are really floating in this fluid, and at the same time, casting their shadows on the retina, the light sensing inner layer of the eye. The debris could be made up of blood, torn retinal tissue, inflammation, vitreous detachment, or could simply mean a normal aging change in the vitreous. Floaters could also signify retinal tears that might be threatening for vision loss.
The vitreous fluid degenerates during the middle age years, often forming minute debris within the eye. Floaters are also often noticed in people who are nearsighted (myopic), and those who have been operated on for cataract or YAG laser surgery. Floaters could interfere with reading, and can be quite bothersome. Even though there is no treatment or cure, they may slowly fade out over time. One possible remedy is to move the eyes up and down when a floater appears. The vitreous fluid may shift, thus permitting the floater to move out of the line of vision.
For the most part, floaters are usually nothing to worry about, being simply a result of the normal aging development. Usually it is recommended to see an ophthalmologist within 24 hours of the onset of symptoms, as floaters could also denote a serious eye disease such as retinal detachment. The vitreous covers the retina surface, and sometimes the retina is torn when degenerating vitreous is pulled away. This leads to a small amount of bleeding, which may be interpreted as a new cluster of floaters. A torn retina is serious, and could possibly develop into a retinal detachment. Consequently, any new floaters that appear should be seen and evaluated by a doctor.
When the vitreous gel rubs against or pulls on the retina, it can produce the illusion of flashing lights. Flashes can be perceived as a sparkle, disco light, fireflies, lightning, fireworks, Christmas tree lights or sparks. The same experience can happen after being hit in the eye, giving the illusion of seeing stars. All of these flashes are generated by any abnormal stimulus to the retina.
Light flashes can happen on and off for many weeks, or even some months. This is a common occurrence during the aging process, and it is generally not cause for concern. At times, however, a significant number of new floaters will appear, accompanied by light flashes, and partial sight loss of peripheral vision could occur. If this happens, it is important to visit your doctor quickly in order to evaluate whether the cause is a torn retina or retina detachment.
Migraine flashes appear as zigzag, shimmering, or even colorful, lines that may move within the visual field. They usually last from five to thirty minutes and can occur in both eyes at once. They are most likely caused by a sudden spasm of blood vessels in the brain. These flashes are often associated with headache, nausea, or dizziness, but more often occur without such symptoms.
As in the case with floaters, an eye specialist should attend to any abrupt onset of an abundance of light flashes. The exam would involve close observation of the retina and vitreous fluid.
Floaters and Flashes are common visual symptoms that can be representative of normal aging changes in the eye or the onset of an eye disease that could lead to vision loss if left unattended. It is always prudent to consult an eye specialist when such vision changes occur.