Happy Holidays from all of us here at Georgia Eye Physicians and Surgeons! As this year comes to a close, we would like to express our deepest gratitude to all of our wonderful patients, many of whom were kind enough to share their stories in our Spotlight Patient blogs. It has been our honor and privilege to be able to serve this fine community, and we look forward to being able to do so for many years to come.
The coming year promises to be an exciting one, with many new breakthroughs in optical and vision enhancing technology just around the corner. The addition of our new LenSx® cataract laser this year has allowed board certified ophthalmologist Dr. William Segal to create consistent incisions and openings in the lens capsule that are up to 10 times more precise than those that can be made during a manual procedure. This unparalleled level of precision combined with sophisticated, real-time image guidance and computer assisted control allows for every intraocular lens replacement procedure to be customized to the specific contours of each individual eye.
We are also pleased that our on-site Optical Center, headed by our Comprehensive Consultative Optometrist Dr. Marc Lay, has been able to help so many people overcome visual difficulties with eyeglasses or contact lenses and achieve a more satisfying quality of life.
The future has never looked brighter at Georgia Eye Physicians and Surgeons, and we thank you all for your support. We hope that we have been able to bring just a little bit more light into your worlds as well. From all of us here at Georgia Eye, may you enjoy a safe and happy holiday season!
Your eyes are extremely precise and delicate instruments, capable of detecting even minute amounts of light or subtle shifts in color, but this sensitivity also makes them extremely vulnerable to damage and injury. According to the United States Injury Registry Summary report, more than 50,000 people permanently lose all or part of their vision as a result of the more than 2.5 million eye injuries that occur annually. While as many of 90% of these injuries can be prevented through the use of protective eyewear, like that carried in our on-site Optical Center, you may not always be able to protect yourself from unforeseen occurrences. So it is extremely important to know what to do when eye trauma does occur.
Injuries to the eye are most commonly the result of airborne particles of sand, glass, wood, plastic, or metal that get blown into the eye. If this occurs, it is important to remember that the eye itself produces tears, in part, to flush such irritants from the clear front layer of the eye, or cornea. Our eyes “water” precisely because the body is trying to protect itself from these foreign bodies. If the material is small enough, you may be able to assist your body’s natural defense mechanism by gently pulling the upper eyelid down over the lower and blinking repeatedly, flooding the eye with extra tears. If this is insufficient to dislodge the particle, carefully flush the eye with a sterile saline solution and use a moist cotton swab to gently wipe away the foreign body. Avoid rubbing the eye, as this could aggravate the injury and cause the foreign particles to scratch the cornea.
Larger objects can pose a much more serious problem, possibly penetrating the cornea and becoming lodged inside it. If you are treating an eye that has been cut or punctured by a foreign object, seek the immediate attention of a medical professional. Do not attempt to wash the eye or remove anything stuck in it. Instead, protect the eye from accidental rubbing by covering it with a rigid, circular object — cutting out the bottom of a paper cup will create an effective protective shell that can cover the eye without touching it. Do not put pressure directly on the eye but simply affix the protective covering using a piece of tape and go to an eye doctor or emergency room right away. Similarly, if the eye has been forcibly struck by a blunt object, like a baseball for example, apply a cold compress to the area around the eye, but do not put direct pressure on the eyeball itself. If there is bruising, bleeding, or a change in vision, or if it hurts when the eye moves, see a board-certified ophthalmologist, like Dr. William Segal, right away.
Lastly, eyes can often suffer significant damage if exposed to household cleaners or other caustic chemicals. If this occurs, immediately wash out the eye using the nearest source of fresh water and contact medical assistance. Continue flushing the eye for at least 15 minutes, keeping the eye wide open and allowing the water to run over and cleanse it. You may need to stand underneath a showerhead or place your head directly beneath a running faucet and use both hands to keep the injured eye open while flushing it. Having information about the specific chemical involved (which is usually printed on the packaging) will help emergency personnel treat the injury more effectively. Avoid rubbing the affected area, as this may cause further irritation or damage, and do not cover or put anything over the eye, then go to an emergency room immediately.
At Georgia Eye Physicians and Surgeons, we are actively involved in research relating to all aspects of vision. One particularly interesting use of the latest visual diagnostic technology is the early detection of mild traumatic brain injuries, or concussions. The majority of concussions are the result of blunt trauma, or a blow to the head, and in children they are most commonly sustained during contact sports such as football, soccer, lacrosse, and hockey. Traumatic brain injuries like concussions often have wide-ranging physical and psychological effects, some appearing immediately after the traumatic event, and many others that may not appear until days or even weeks later. In fact, it is estimated that the vast majority of concussions (approximately 90%) do NOT result in a loss of consciousness, making diagnosis more challenging than previously thought. As a result, concussions are often misidentified as ‘low severity’ injuries. Patients are frequently treated with a ‘sit-and-wait’ approach, and it is only after symptoms have become debilitating that people seek care of their own accord.
Since an estimated 3.8 million recreation and sport-related concussions occur in the United States every year, many are looking for better ways to help diagnose concussion patients so that prompt treatment can be rendered. Although concussions are not visible in routine scans of the brain, they are detectable when important aspects of brain function are measured. This is where an optical examination can act as an invaluable diagnostic tool. More than 50 percent of the neural connections within the brain are involved with some aspect of vision, so many of the earliest signs of traumatic brain injury can be detected by examining the function of the cranial nerves involved in vision and eye movement. For example, damage to the nerves that control the tiny dilations and contractions of the pupil may also cause the pupils to react differently to light or to even be different sizes. Additionally, most individuals that have suffered a concussion will complain of vision related problems, such as blurry vision, light sensitivity (photophobia), eye fatigue, double vision (diplopia), or reading difficulties. Quick, easy to administer sideline visual tests, like the King-Devick Test, have been developed to accurately assess the likelihood of concussion following injury.
Optometrists and ophthalmologists are also crucial in helping rehabilitate patients’ vision after such an injury has been sustained. Because so many of the connections within the brain are involved with the process of vision, it is hardly surprising that vision problems are so common following an acquired brain injury. Concussions can result in a reduction in the eye’s focusing ability, resulting in blurred vision at close or far ranges. This inability to focus can eventually result in headaches, eyestrain, or even double vision when performing tasks that require close focus, such as reading. Many of the visual conditions that result from a concussion can be successfully managed with prescription eyeglasses or contact lenses, even a relatively small prescription correction can often decrease blurred vision enough to eliminate eyestrain and its related symptoms.
Although an estimated 36 million Americans wear contact lenses, few people fully and completely understand how they work. At Georgia Eye Physicians and Surgeons, we have always been committed to providing our patients with the most complete and up-to-date information available so that they can make informed decisions about their eye health. So here are some answers to a few of the most commonly asked questions about contact lenses.
What do contacts actually do? Normally, light enters the cornea in the front of the eye and is focused by the lens into a single point on the retina in the back. Special receptors that line the retina then convert this light into electrochemical signals that can be processed and interpreted by the brain. However, imperfections in the shape of the cornea, or refractive errors, can prevent light from focusing precisely on the retina. Contact lenses work by bending, or refracting, light before it enters the lens of your eye.
An eyeball that is too long causes light to focus in front of the retina, resulting in myopia, or nearsightedness. Contact lenses to correct this condition are thinner at the center than at the edges so that they can spread the light away from the center of the lens and move the focal point of the light forward. On the other hand, hyperopia, or farsightedness, occurs when the eyeball is too short, causing it to focus light rays behind the retina. In these cases, the lens is thicker at the center and thinner at the edges to bend the light toward the center and move the focal point back.
How do contacts treat astigmatism? In astigmatism, the cornea is irregularly-shaped, causing light to focus at several different points on the retina, distorting vision and posing a more complicated problem than other, more straightforward refractive errors. Whereas lenses used to correct myopia and hyperopia have the same corrective power throughout the lens, astigmatism requires a special “toric” lens that is customized to each individual’s specific vision needs. These toric contact lenses have different angled curvatures to correct vision, making them thicker in certain parts of the lens and thinner in others.
What if your eyes need correction for both near AND distance vision? Several different conditions, including presbyopia, a common eye condition that frequently develops as people get older, can cause the eye to lose its ability to accommodate from near to far focus, requiring both near and far correction. This is typically accomplished with one of several types of bifocal contact lenses. A translating lens simply mimics bifocal glasses. The lens is divided, with the distance correction at the top and the near correction at the bottom. Concentric bifocal lenses place the near correction in a small circle at the center of the lens and the distance correction in the outer lens surrounding it. Finally, an aspheric lens combines the design of the concentric bifocal lens with features of progressive eyeglass lenses, where the different prescriptive powers are blended across the lens.
How do contact lenses stay in place? The tear ducts constantly produce tears, a lubricating combination or natural oils and water, which flow into the space between the eyeball and lids. When the eyes blink, this fluid is spread across the surface of the eye, keeping them free from irritation. Contact lenses adhere to the layer of tear fluid that floats on the surface of the eye. Eyelid pressure also holds them in place. As the eye blinks, it provides lubrication to the cornea and helps flush away any impurities that may have become stuck to the lens. Since both toric and multifocal lenses have different focusing power in different portions of the lens, it is extremely important that they remain properly positioned on the eye. In order to accomplish this, they are often weighted more along the bottom or have thin edges along the top and bottom to keep them fixed in one position.
The eyes are amazingly sophisticated devices capable of detecting and interpreting visual data under a wide range of conditions. The sensitivity of the eye automatically adjusts to an impressively large range of ambient light levels. The optics of the eye can concentrate light energy on the retina by a factor of 100,000 times, which is one of the reasons the eye can be susceptible to damage from sun exposure, but is also the key to understanding one of the most fascinating features of the eye: its ability to adapt to conditions of low light.
In simple terms, everything we see is the result of complex processes that take place within the anatomy of the eye. Electro-chemical signals are sent to the brain by tiny, light sensitive receptor cells covering the retina. There are two distinctive types of receptor cells: rods, which are the most common and are found predominately in the periphery of the retina, and cones, which are located mostly in the center and near periphery of the retina. Although there are about seventeen rods to every cone, it is the cones, concentrated in the center of the retina, that are responsible for the resolution of fine detail and color discrimination. Unfortunately, the cones only function in good illumination. While the rods are unable to distinguish colors and have poor resolution, they have a much higher sensitivity to light than the cones and are the reason we are able to see in dimly lit conditions. The dimmest light in which the rods can function is equivalent to an overcast night with no moonlight, while the cones cease to function in anything less than a night with 50% moonlight. Thus a white light barely bright enough to be seen by the rods must be increased in brightness 1,000 times before it becomes visible to the cones.
Because the central portion of the retina, called the foveola, possesses a high degree of cones but is completely devoid of rods, everyone has a blind spot in the center of their visual field at night. A person attempting to see in low-light conditions has to depend entirely on the rods at the edges of the retina. Hence it is usually most effective to look approximately 15-20 degrees to one side, above, or below an object in order to place its image on the part of the retina that possesses the highest density of rods. Individuals requiring keen night vision, like pilots, are taught to fixate to one side of an object to avoid the central blind spot or to scan, utilizing the most sensitive parts of the retina.
Despite the fact that the rods in the retina can detect extremely low levels of ambient light, they have significantly reduced visual acuity. Specifically, it is often difficult for them to distinguish objects at night if they are not either lighter or darker than their background, as they lack the finely focused detail and color detection present in cones. This limitation means that night vision relies on small differences in the brightness between objects and their background, and so any transparent medium between the eye and the object should be kept spotlessly clean. Light reflected from dirty windshields, visors, spectacles, or even fog or haze may significantly reduce the eye’s ability to discriminate between levels of contrast, which is one of the reasons that those who wear glasses frequently complain of poor night vision. Additionally, those with astigmatism, a condition when the cornea, or lens of the eye, is irregularly curved and light rays refract and create blurred vision, often suffer from poor night vision. The dilation of the pupil to let in more light, a natural response to dimming conditions, engages more of the distorted cornea, exaggerating the refractive error. Finally, glaucoma, drug toxicity and numerous hereditary disorders can also significantly reduce night vision acuity, resulting in night blindness, as can long-term vitamin A deficiency resulting from chronic starvation, alcoholism, deficient fat absorption, and diseases of the liver.
If you have any questions about how the eyes work or are interested in any of the many services offered at Georgia Eye Physicians and Surgeons, please contact us today. Be sure to follow Dr. William Segal and Dr. Marc Lay on Facebook, Twitter, and Google+ for more tips for healthy eyes.
At Georgia Eye Physicians and Surgeons we’re committed to exceptional eye care for our patients and their families. We know how much the health of your eyes means for your quality of life. We’re committed to serving your complete eye care needs with the respect and care we would use in treating our own family.