Anyone who has been to an eye doctor has probably had a refraction performed. The refraction is the portion of the eye exam that measures your ability to see an object at a specific distance. From the exam chair, you look through the phoropter toward an eye chart. The phoropter contains multiple lenses of different strengths that can be moved into view. The examiner alternates lenses and asks you which is clearer. When you are able to read the chart most clearly, the lenses required are noted. This process takes time and patience due to the interaction required for the most accurate outcome.
Why is the Test Performed?
The doctor will compare the information obtained from your refraction with your current glasses to determine if vision changes are due to the need for new lenses or to a possible medical problem that requires further exploration. Whenever a patient experiences a change in vision, this test is necessary to identify the amount and cause of the change. The refraction also allows us to track the progress of diseases or treatments.
Will Insurance Pay for Refractions?
Refraction has always been a non-covered service under the Medicare program. As a result, your secondary insurance will typically not cover it.
Other insurance plans vary depending on your individual benefit coverage. In our experience, unless you have specific vision benefits, your insurance will not cover the cost of refraction.
In most cases, we ask that the fee for refraction be paid at the time of your visit. Should your insurance pay for this service, the charge will be credited to your account. If you have any questions about refractions, please feel free to contact our office.
We participate in Medicare as well as most major private insurance plans. Additionally, we participate in many Medicare Advantage plans as well as a number of AHCCCS options. Plans we accept are listed below. We will do our best to keep this list up to date and accurate, however please always inquire about our participation in your specific plan when scheduling a new appointment, as our provider status may change without notice.
- Administrative Enterprises
- Aetna US Healthcare PPO and HMO-(Managed thru Schaller Anderson)
- Arizona Foundation for Medical Care
- Arizona Medical Network (RanAm)
- Blue Cross Blue Shield HMO, PPO, Federal and Out of State
- Cigna PPO, Open Access Plus and HMO
- Coventry Advantra Freedom Network
- Eye Med
- First Health
- Humana PPO
- Mountain State Administrative Services
- PHS/Multiplan Network
- Southwest Administrators
- Superior Vision
- Tricare Health Care Alliance
- United Healthcare
Medicare Advantage Plans
- AARP Medicare Complete (United Health Care)
- Advantra Freedom Coventry Health Plan
- Aetna Medicare Open Plan
- Any, Any, Any Plan (Universal Health Care)
- AP/IPA Personal Care Plus
- BCBS Medicare Advantage
- Health Choice Generations
- Healthnet Medicare Advantage
- Humana Medicare Advantage
- Mercy Care Advantage
- Secure Horizons (most plans)
- Unicare Security Choice
- USAA Preferred Care
- Arizona Physicians IPA (APIPA)
- Health Choice
- Mercy Care Plan
- Pima Long Term Care
Two offices and a laser surgery center serve Tucson and southern Arizona. Our offices are open from 8am to 5pm Monday through Friday. Please call 520-293-6740 to schedule an appointment with one of our physicians.
Optical shop hours are also Monday through Friday, 8am to 5pm. No appointment is necessary. Please stop in to browse or speak with one of our licensed opticians any time.
Main office and outpatient surgical center
5599 North Oracle Road
Tucson, AZ 85704
Located southbound between Orange Grove and River Roads
Rooney Ranch office
10425 North Oracle Road, Suite 135
Oro Valley, AZ 85737
Located at the southwest corner of Oracle Road and Pusch View Lane in the office complex- enter from Pusch View Lane and travel south to suite on left
Arizona Eye Laser Center
6837 N. Oracle Rd, Suite 15
Tucson, AZ 85704
Located between Prince and Ft. Lowell on the west side of the street
Please bring your insurance card, as well as any necessary referrals. For initial or annual examinations, we will need information regarding your medical history and current medications. Please arrive a few minutes early to complete paperwork. Some of the required forms can be downloaded from this web site by clicking here.
Please assist us with our efforts to protect your identity and your health information. To comply with new Federal Red Flag regulations we are requesting your driver’s license or other photo identification at the time of your appointment. We are also asking for your current insurance card. If your photo ID does not show your current address, please bring a utility bill or other correspondence showing your current address. This information will be placed into your electronic medical record. We appreciate your assistance.
What Is Glaucoma?
Glaucoma is a group of eye disorders that can lead to progressive loss of vision, often without any symptoms. Visual loss results from damage to the optic nerve, which transmits signals from the eye to the brain, much like an electrical cable. Once nerve fibers are damaged by glaucoma, the information they supply can no longer reach the brain. Peripheral vision is usually lost first. Because central vision is preserved until late in the disease and pain is usually absent, most people with glaucoma don’t realize that anything is wrong. It is estimated that as much as one to two percent of the US population has open angle glaucoma, and that half of those affected have not been diagnosed.
It was once believed that glaucoma is caused by high pressure within the eye, known as intraocular pressure, or IOP. While IOP plays a large part in glaucoma, it is now considered a major risk factor for the development of the disease. The higher the pressure the more likely one is to get glaucoma. However, 20 to 30 percent of patients with glaucoma have normal intraocular pressures, indicating that other factors must be involved. Nutrition, blood flow, and toxins may all play a part, though details are currently not well understood. Extensive research is being conducted to identify these factors.
Types of Glaucoma?
Glaucoma is usually broken down into two major categories: open angle glaucoma and closed angle glaucoma. To understand the difference, we must first know a bit about how eye pressure develops. The eye is essentially a hollow sphere filled with fluid. In the front section of the eye, this fluid is called the aqueous humor. The aqueous humor is produced by the specialized cells of the ciliary body, which is located behind the colored part of the eye, called the iris. Fluid then travels through the pupil, the central opening in the iris, to enter the anterior chamber, which is the space in front of the iris and behind the cornea. The cornea and iris meet peripherally to form the drainage angle of the eye. Within this angle is a structure known as the trabecular meshwork, which is the sieve-like entrance to the drainage system of the eye. The aqueous passes through this mesh of tissue, exits the eye, and is collected by veins to return to the bloodstream.
Risk Factors for Glaucoma
A number of risk factors for the development of glaucoma have been identified:
- Intraocular pressure, as already mentioned, is presently the most significant. Intraocular pressure normally runs between 9 and 21 millimeters of mercury. IOP above 21 is considered high, and with increasing pressure comes increasing risk of glaucoma. However, not all high pressure will lead to glaucoma. Furthermore, as mentioned earlier, glaucoma occurs frequently in the presence of normal levels of IOP. Therefore, intraocular pressure alone cannot be used to diagnose the disease, and must be evaluated as part of the entire clinical picture.
- Race is another significant factor. African Americans are five to six times more likely than Caucasians to be affected by the disease, which tends to be more severe and progress more quickly in this population. Latinos are also at greater risk than Caucasians. The reasons for these racial differences are not well understood, but are most likely genetic.
- Family history of glaucoma, particularly in a first degree relative, i.e. parent or sibling, increases one’s risk. The genetics of glaucoma, however, are usually not simple, and there is no way to predict which family members will be affected. At the time that this article was last updated, there have been 14 genes identified as causing or contributing to a form of glaucoma, with new genes being discovered fairly frequently. Within the next 5 to 10 years, genetic testing may become routinely available to aid in the diagnosis and prognosis of glaucoma.
- Age Glaucoma is uncommon under 40, but risk increases with each decade of life.
- High blood pressure has been associated with increased intraocular pressure in some studies, but it remains unclear exactly how significant this association is clinically.
- Low blood pressure may be a risk factor for glaucoma progression, particularly in patients with low tension glaucoma, a form of open angle glaucoma in which the pressure is in the normal range, often quite low. The key seems to be the diastolic perfusion pressure- the pressure experienced by the tiny blood vessels of the optic nerve at the end of each heartbeat, measured as the diastolic blood pressure (the second number in your blood pressure measurement) minus the intraocular pressure. Diastolic perfusion pressures below 50 appear to be assoicated with increased risk of optic nerve damage and glaucoma. This is currently an area of very active study.
- Sleep-associated breathing disorders, such as sleep apnea, may also be a risk factor, particularly for low tension glaucoma, again due to abnormal blood flow to the optic nerves.
Other possible risk factors include diabetes and myopia (nearsightedness), however studies have provided inconsistent results as to the degree of association with these factors.
Your physician will perform a complete medical history and eye examination in order to determine your risk factors and search for signs of disease. The entire eye will be carefully evaluated, with special attention paid to the optic nerve, the structure damaged by glaucoma. The optic nerve is viewed through your dilated pupil using a special lens and an ophthalmic microscope. Gonioscopy may also be performed, in which a special mirrored lens in placed on your eye in order to directly examine the drainage angle and trabecular meshwork. The thickness of your cornea may also be measured, as an abnormally thick or thin cornea can affect the accuracy of intraocular pressure measurement. After your exam, if glaucoma is suspected, additional tests may be recommended. More about these tests can be read here.
- Stereoscopic optic nerve photographs are taken with a specialized camera system, providing true, three-dimensional images of the optic nerves. These photos can be repeated over time and examined for signs of progressive nerve damage. In order to obtain clear photos, pupillary dilation is required. This examination usually takes about 45 minutes, including the time required for dilation.
- Visual field testing is conducted to evaluate the function of the optic nerve. As glaucoma damage progresses vision is lost, typically beginning in the periphery and moving toward the center. Computerized visual field devices flash a series of lights in your peripheral vision in order to map out any areas of visual loss. Again, by repeating this test over a period of time, stability or progression of disease can be ascertained and treatment adjusted as necessary. Completion of this test can take anywhere between 20 and 45 minutes, depending upon the exact type of examination your doctor orders. Your eyes will not be dilated for a visual field.
- Ocular Coherence Tomography, or OCT, uses a laser to create a three-dimensional image of the optic nerve and surrounding retina, which is then analyzed by a computer. This allows your physician to better evaluate the structure of the fibers of the optic nerve, which are altered by glaucoma. Changes in the structure of the optic nerve occur early in glaucoma, often preceding any visual changes, and identification of these changes may be the best way to diagnose disease. By repeating this exam over time, the success of glaucoma treatment can be monitored. Performance of this test usually does not require dilation, and takes about 15 to 20 minutes.
Unfortunately, the diagnosis is glaucoma is not always straightforward, even after all testing is performed. There is significant variation in the appearance of normal optic nerves, with many healthy nerves looking a bit suspicious for glaucoma. Because glaucoma is usually a very slowly progressive disease, it is not uncommon for patients to be watched carefully without treatment while the diagnosis of glaucoma is considered. These ‘glaucoma suspects’ may be followed for many years before a final diagnosis is made and treatment is initiated. If suspicion is relatively low, ‘watchful waiting’ avoids the potential risks and side effects of treatment.
Open Angle Glaucoma Treatment
Treatment for glaucoma is individualized for each patient’s specific condition. When required, three basic options are available, all of which serve to lower the intraocular pressure. First-line therapy typically involves medication, usually applied topically as eye drops. Medications lower pressure by either decreasing the production of fluid within the eye or by opening the drainage system to allow more fluid out. There are numerous classes of medications available, each with its own set of side effects. Your doctor will suggest medications for you based upon their safety and efficacy, taking your general health and use of other medications into account.
Another treatment option is laser surgery. Known as laser trabeculoplasty, this procedure has been performed since the early 1980s using an argon or diode laser. There is a 60 to 75 percent success rate of lowering intraocular pressure by approximately 20 to 30 percent. The treatment effect typically lasts about five years, and can later be repeated if necessary. Trabeculoplasty is often a good early treatment option, avoiding the need for additional medications. The procedure is performed in the physician’s office with the patient comfortably seated at a treatment microscope. Over a period of about five minutes, the laser is directed at the drainage channels within the eye, serving to “unclog” the eye’s drain and allow more fluid to exit. Postoperatively, one can expect mild discomfort, sensitivity to light, and blurred vsion for a few days. Eye drops are often prescribed to control these symptoms.
It is now possible to perform trabeculoplasty using a different type of laser. Called “selective laser trabeculoplasty”, or SLT, this procedure can theoretically be repeated indefintely, whereas standard laser trabeculoplasty can only be repeated once. While this is promising, the efficacy of multiple SLT treatments has not yet been established, and most studies indicate that SLT and traditional laser trabeculoplasty are equivalent in terms of efficacy. After a thorough examination, your physician will determine whether you are a candidate for either procedure. More can be learned about trabeculoplasty by clicking here.
The final treatment option, when medications and laser therapy have either failed or are no longer tolerated, is glaucoma drainage surgery. A number of techniques are available, all with the same goal of bypassing the damaged, clogged drainage system of the eye. In effect, a surgical drain is created, allowing the aqueous humor to escape the eye without having to pass through the clogged trabecular meshwork. The most commonly performed operation, called a trabeculectomy, often produces very low eye pressures, lower than can be achieved with medication or laser. Such low pressures are often required in advanced glaucoma to prevent further loss of vision. Occasionally, another procedure, known as a tube shunt or glaucoma drainage device, may be required. In this type of surgery, a tiny plastic tube is inserted into the eye to drain fluid. The type of glaucoma and the condition of your eye will influence your physician’s decision regarding which procedure to perform. While effective and safe, surgery entails more risks than other therapies, and serious complications, although rare, can occur. Read more about trabeculectomy here, or drainage devices here.
Newer surgical techniques seek to avoid bypassing the eye’s natural drainage canal in favor of trying to re-establish a more normal drainage pathway through the damaged trabecular meshwork. Known collectively as ‘non-penetrating glaucoma surgery,” numerous procedures are being studied and evaluated. One such procedure, known as canaloplasty, is now offered by our practice and is detailed here. While effective at lowering intraocular pressure, these surgical techniques generally cannot achieve pressures as low as with standard trabeculectomy. While non-penetrating surgery is apporpriate for some, trabeculectomy remains the procedure of choice for most patients requiring surgical management of glaucoma.
Your physician will discuss these options with you and will recommend the treatment he or she believes to be most appropriate for your condition.
Finally, we are often asked if there are any lifestyle or dietary issues that might affect glaucoma. A number of factors have been studied, and the simple answer is that there are no lifestyle modifications which have been found to be clearly beneficial to the long-term management of glaucoma. The following factors have been found to affect intraocular pressure:
- Caffeine intake has been associated with elevated IOP. Studies indicate that a single cup of coffee can elevate IOP by 1 to 4 millimeters of mercury for at least 90 minutes. There have been no studies to determine whether caffeine intake is detrimental to glaucoma management, however. We recommend moderation- a cup or two of coffee or soda each day are unlikely to cause any significant problems.
- Alcohol has been found to cause a dose-dependent decrease in IOP after ingestion. However, some studies suggest that regular alcohol consumption is associated with increased IOP. No studies have shown alcohol use to be a risk factor for the development of glaucoma. Again, moderation is recommended.
- Dietary issues remain unclear. Little research has been performed on the role of antioxidants in glaucoma, although one study failed to find a significant role for antioxidants such as carotenoids, vitamin C, and vitamin E in the development of glaucoma. In another study, dietary fat intake did not appear to affect risk of glaucoma, although types of fats such as omega-3 or omega-6 fatty acids may have some role in regulating IOP. Clearly, more study is needed in this area, and no dietary recommendations can be made in this regard.
- Exercise has generally been found to be associated with reduced IOP. Acutely, exercise lowers IOP in the immediate post-exercise period, the degree of lowering directly related to work intensity. Furthermore, it seems generally accepted that physical fitness due to a consistent exercise regimen results in lower baseline intraocular pressure. Again, however, the affects of exercise and physical fitness on glaucoma progression are not well studied. It appears sensible to maintain a modest level of physical conditioning.
- Cigarette smoking has been found in a number of studies to have minimal effect on IOP, possibly causing a modest elevation, and no clear association with the development of glaucoma. However, considering the host of other health concerns associated with smoking, including increased risk of cataract and macular degeneration, we strongly advise our patients to avoid smoking and other tobacco product use.
- Other activities, such as weight lifting, yoga, and playing high-resistance wind instruments such as the trumpet, cause transient and significant elevations in intraocular pressure. To our knowledge, however, there have been no studies indicating increased risk of developing glaucoma or causing glaucoma progression among people who perform these activities.
Again, based on the above, no specific recommendations can be made regarding lifestyle alterations in the management of glaucoma. However, given the other known health implications of many of these factors, we generally recommend that our patients maintain some level of age and health-appropriate exercise, avoid smoking, avoid excessive alcohol and caffeine intake, and eat a balanced diet high in fruits and vegetables as suggested by the USDA.
Narrow Angle/Angle Closure Glaucoma Treatment
Narrow angles and angle closure glaucoma, while often treated with some of the same medications and surgical procedures as open angle glaucoma, have one notable difference. In these conditions, the problem of a narrow angle caused by the iris and cornea being too close together is often exacerbated by a situation known as pupillary block. Remember that aqueous humor, the fluid in the front of the eye, is produced behind the iris and must pass through the pupil before gaining access into the trabecular meshwork.Flow of aqueous humor through a peripheral iridotomy Due to resistance of flow at the pupil, there is actually a slightly higher pressure behind the iris than in front, and this tends to bow the iris forward, contributing to the already narrow angle, and further blocking outflow of fluid from the eye. This papillary block is commonly the cause of acute angle closure in predisposed individuals. Treatment is aimed at alleviating this condition. A laser is used to create a small opening (or openings) in the periphery of the iris. Known as laser peripheral iridotomy, this procedure creates a lower resistance pathway for aqueous to pass from behind to in front of the iris, preventing papillary block and significantly reducing or eliminating the risk of acute closure of the angle. Iridotomy is effective and safe, with little risk of significant complication. The same procedure is required emergently to treat an actual attack of angle closure, however is much more difficult to perform and may be too late to prevent permanent damage to the eye. Therefore, if your physician finds narrow angles, laser iridotomy may be recommended on a prophylactic basis. More about narrow angle glaucoma and its treatment can be found here.
Much research is ongoing in the field of glaucoma. Genetic testing to help identify those at risk for the disease shows promise. Newer, better surgical techniques are constantly being evaluated to identify procedures which are more effective and safe. Much interest now focuses on medications which may provide what is known as neuroprotection. This term describes the protection of the optic nerve from damage by a number of factors, including poor blood supply, toxins, and inadequate nutrition. Neuroprotective medications are considered quite important, as we know that intraocular pressure is not the only influence on glaucoma progression, yet it is presently the only treatable aspect of the disease. Availability of these drugs will eventually be a major step forward in the treatment of the disease, however results from human trials are not yet conclusive.
If, after reading this information, you still have questions or concerns about glaucoma, please contact us to schedule an appointment for a complete evaluation with one of our doctors.
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It is estimated that more than 70 million Americans are nearsighted, and millions more are farsighted or have significant astigmatism. The majority of these individuals are reliant upon eyeglasses or contact lenses for clear vision. Despite great improvements in the visual quality achievable with modern lenses, many would prefer to leave their glasses and contacts behind in favor of good, unaided vision.
The first refractive surgical procedure, radial keratotomy (RK) was introduced to the United States from Russia in 1978. Since then, numerous other surgical options have become available for the correction of refractive errors, and surgical vision correction now ranks among the most commonly performed elective surgical procedures in the U.S. The following information is provided to educate you about the surgical choices available, and to help you decide if refractive surgery is right for you.
Flashes and floaters are among the most common symptoms described to eye doctors. In the majority of cases, these symptoms represent a series of benign changes within the eye, usually related simply to age. Rarely, they may be associated with retinal damage which may require treatment, and therefore all new flashes and floaters merit a visit to a physician for evaluation. The following discussion will explain the details of these changes.
Most of the eye, which is essentially a hollow sphere, is filled completely by a clear structure called the vitreous. This vitreous, which is composed primarily of water and long strands of suspended molecules, is fairly solid when we are young, with the consistency of loose Jello.
As we age, the vitreous gel begins to break down into its components, becoming more liquid with clumping of the strands, a process known as syneresis. These clumps are the first “floaters” which most people recognize. They are often described as small spots or hairs which seem to move or float around as the eye moves.
As the breakdown of the vitreous gel continues, it begins to lose its attachment to the retina, the thin film which lines the inside of the eye. Flashes, often seen as brief bursts of light in the periphery of vision, occur as the retina is stimulated by the loosening vitreous. Eventually, the vitreous separates from the retina, often with the development of new, large floaters as the semi-solid gel now floats freely within the eye. This final separation of vitreous from retina is known as a posterior vitreous detachment, or PVD. (See diagram at above)
The entire process of vitreous detachment is generally nothing more than a nuisance, with larger floaters occasionally interfering with vision, causing transient blurring. Rarely, however, the separation of vitreous and retina can cause problems. In some cases, the vitreous is abnormally adherent to the retina.
Rather than simply peel free, it clings tightly to the retina, leading to a retinal hole or tear. Vitreous fluid can then pass through the tear and collect beneath the retina, separating it from the wall of the eye. This is known as a retinal detachment. (See diagram at left)
The new onset of either flashes or floaters in an eye should be evaluated by an eye doctor within a few days. While relatively uncommon, a retinal tear can be easily treated with a brief, painless laser procedure, preventing the development of a retinal detachment. Once a significant retinal detachment occurs, more involved surgery is usually necessary to repair the damage.
If you experience the onset of multiple flashes, new floaters- particularly numerous small floaters, or a veil or curtain in the periphery of your vision, please call for an appointment. We will perform a thorough evaluation and, if necessary, arrange for treatment. Click the contact us link for information about scheduling your visit.
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Much like the lens of a camera, the eye’s lens functions to focus light entering the pupil upon the retina, a thin membrane in the back of the eye. The retina functions like film, sending what the eye sees on to the brain through the optic nerve. Just as a dirty camera lens will take a blurry photograph, a cataractous human lens can cause a number of visual disurbances, including blurring, haziness, glare, difficulty judging colors, and eventually significant loss of vision in the eye.
For most people, cataracts are simply a matter of age.
Nearly everyone develops cataracts over time, though the rate at which the lens undergoes these changes is quite variable. Some may note significant visual disturbances in their 40s, while others may live into their 80s and never be very bothered by their vision. The reasons for these differences are not well understood. Genetics may play a part, with some simply more succeptible to cataract at an earlier age. Environmental factors, such as exposure to sunlight or certain diets, may one day be found to play a role, however current data regarding the effects of these elements are not conclusive.
While most cataracts are age-related, some are not. Some people are born with cataracts. Others may develop cataracts due to illness or disease, trauma, or use of certain medications. For example, those on chronic corticosteroids such as prednisone often develop lens opacities. By understanding your full medical history, your doctor can determine whether your cataracts are related to any of these factors.
Presently, the only available treatment for cataracts is surgery.
Many often ask if cataracts can be prevented. Given our current lack of understanding of their causes, the simple answer is no. Some eye doctors advocate the use of ultraviolet light-blocking sunglasses. While not definitive, some studies have suggested that ultraviolet light may be partly responsible for cataract progression, as well as for other eye diseases such as age related macular degeneration. The use of sunglasses may therefore help, and certainly will not cause any harm. Similar advice might apply to antioxidants such as vitamins A, C, and E. While studies have produced conflicting information, some indicate that these vitamins may slow cataract growth. Speak with your medical doctor prior to starting any high-dose vitamin program.
Cataract surgery may be right for you if you experience any of the symptoms noted above, such as significant blurring, haziness, or glare. If any of your work or leisure activities are affected by poor vision, a complete eye examination will help your physician determine the cause. Patients with cataracts often complain of difficulty reading or performing close-up work, trouble driving- especially at night due to glare and starbursting around lights, or difficulty following a golf ball.
Modern cataract surgery is performed without discomfort on an outpatient basis. Gone are the days of large incisions, multiple sutures, and prolonged bedrest. Today, incisions are tiny, typically measuring only three millimeters, or about an eighth of an inch. Stiches are seldom necessary, and recovery, both physical and visual, is rapid. Many patients drive and return to their usual level of activity the day following surgery.
The surgical procedure: phacoemulsification
The details of cataract surgery, known as phacoemulsification, will be described next. Please visit our Outpatient Surgery Center page for additional information about your surgical day experience in our state-of-the-art facility.
Once adequate anesthesia has been achieved, the area around the operative eye will be cleansed for sterility and a surgical drape will be placed. A small device known as a speculum will then be placed to keep your eye open during the procedure. There will be no discomfort. A small incision is then made in the cornea, or clear window at the front of the eye, and a viscous gel is injected into the eye in order to maintain space and protect the other ocular structures during surgery. The “main” corneal incision is then carefully made using an extremely sharp and precise blade made of diamond. Next, a circular opening is created in the front of the thin membrane, or capsule, which surrounds the lens, and fluid is injected inside to separate the entire lens from its attachment to the capsule. The cataractous lens is then removed using phacoemulsification, the amazing technology behind modern cataract surgery. The phacoemulsification machine produces ultrasound waves within a tiny handpiece, pictured to the left, which is inserted into the eye. This causes the metal tip of the instrument to vibrate very rapidly, up to 40,000 times each second, dissolving the cataract material which is then aspirated out of the eye. Additional instruments are used to clean all the cataract from the lens capsule, which is then refilled with more viscous gel. An artificial, permanent lens implant, made of a type of plastic, is then inserted into the capsular “bag,” taking the place of your natural lens. This implant, which helps focus the incoming light on your retina, is held in palce by two haptics, or curved arms, as seen in the photo below. Once the implant is in place, the incisions are closed, usually without stitches, and the surgery is complete.
Pre-operative measurements and intraocular lens implants
Prior to surgery, your eye will be carefully measured for the proper strength of lens implant. (Read about eye measurements and IOL calculations here). The implant can be chosen to focus your eye at any distance you desire. While most choose to focus at distance, some prefer to see most clearly at near, particularly if they have always been myopic, or nearsighted. At Fishkind, Bakewell & Maltzman we perform these measurements with the Zeiss IOL-Master, the most advanced, accurate device for this purpose, which uses a laser to scan the eye in just seconds. While these calculations are extremely accurate in most cases, the expected results are not always achieved. Most patients obtain vision good enough to drive without glasses. Rarely, the post-operative refraction (eyeglass prescription) will be significantly different than exptected. In these unusual cases, additional surgery, including removal and replacement of the lens implant, may be required to achieve the desired result. The appearance of an implant in the eye at the end of surgery is shown below.
The majority of lens implants inserted during cataract surgery are considered ‘monofocal,’ meaning that they focus light at only one location, usually in the distance. This means that reading glasses will be required for close-up tasks such as reading- without them near vision will be blurred. Another option is the ‘multifocal’ lens implant. Such implants allow for clear vision at distance, as well as good vision at mid-range and near. Each type of lens has specific advantages and disadvantages. You can discuss these options with one of our physicians during your evaluation. Please click here to read in greater detail about lens implant options.
Management of astigmatism
Astigmatism is a form of refractive error in which perpendicular lines are focused at different distances within the eye. Significant astigmatism occurs in as many as one in three people and can cause blurred vision, visual fatigue, and squinting if not corrected with glasses or contact lenses. In early life, most astigmatism is due to an irregular shape of the eye, in which the cornea is steeper in one meridian than the other. As we age, many develop astigmatism due to irregular thickening of the lens as cataracts develop. This latter form of astigmatism will disappear when a cataract is removed, however any remaining corneal astigmatism will blur vision, increasing the likelyhood that glasses will be necessary for clear vision postoperatively.
Fortunately, for those who desire the best possible uncorrected distance vision after surgery, astigmatism can be reduced or eliminated surgically at the time of the cataract operation. This is performed in one of two ways, depending upon the amount of astigmatism present prior to surgery. For lesser degrees of irregularity, extra incisions called “limbal relaxing incisions” can be made in the cornea using a very precise diamond blade. These incisions serve to flatten the steeper meridian of the cornea, making it even in all directions. For larger amounts of correction, limbal relaxing incisions are not enough to overcome the irregularity. In such cases, a special lens implant known as a “toric IOL” can be placed in the eye. Like eyeglasses, which are crafted with cylindrical lenses placed in a specific axis to correct one’s particular degree of astigmatism, a toric implant with the correct cylindrical power is carefully rotated into the precise position within the eye to neutralize the corneal astigmatism.
Once removed, a cataract does not return.
However, the back side of the lens capsule, which remains intact at the time of surgery in order to support the implant, can become cloudy over time. This opacification, sometimes referred to as a “secondary cataract,” can affect vision much the way the cataract once did. If this occurs, a brief, painless laser procedure performed in the office can clear the opacity from the implant. The capsular opacification does not recur once this is performed.
Modern cataract surgery is safe and effective, capable of rapidly improving your vision and putting you back into life. Don’t let poor vision slow you down. Call us today to schedule an appointment with one of our doctors to find out if cataract surgery can help you. Please click on the contact us link above.
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Posterior Capsular Opacity and YAG Laser Capsulotomy
The back side of the lens capsule, the clear membrane that surrounds the natural lens, remains intact at the time of cataract surgery in order to support the intraocular lens implant. Over time this membrane, known as the posterior capsule, may become thickened and hazy, causing blurred vision or glare, much as a cataract can. Posterior capsular haziness, or opacity, is sometimes referred to as a “secondary cataract,” but is not re-growth of the cataract itself. Once removed, a cataract does not return.
Development of capsular opacity varies from person to person. If significant haze develops to the point that it affects vision, a brief and painless laser procedure called YAG capsulotomy can be performed in the office to clear the opacity from the implant. The capsular opacity generally does not recur once this is performed.
The YAG Capsulotomy Procedure
YAG capsulotomy is a short, completely painless in-office procedure. Most patients are able to drive to and from their appointment alone, although the treated eye will be dilated, possibly causing blurry vision for a short time following the procedure. The actual procedure is described below:
- The eye to be treated is dilated with topical medications (eye drops).goes
- You are seated at a slit-lamp microscope, identical to the type used to examine your eyes during a regular appointment.
- As the procedure begins, you will be asked to simply look straight ahead, or at a provided fixation target.
- During the procedure, which generally lasts less than a minute, you will see brief flashes of light and will hear a snapping or popping noise. You will feel no discomfort at all.
- Once the treatment is complete additional eye drops or pills may be given to control intraocular pressure.
- During the few days following the procedure you may notice some new floaters in the treated eye- this is normal. Vision will initially be blurry but should clear by the following day.
- You may return immediately to your normal level of activity with no restrictions.
Risks of YAG Capsulotomy
All laser procedures have some risk. Serious complications of capsulotomy are very rare and can include damage to or dislocation of the lens implant, retinal tear or detachment, or injury to other ocular structures such as the iris or cornea. Brief elevation of intraocular pressure may occur, and medication is often given at the end of the procedure to avoid problems with pressure.
If you have any questions about this or any other procedure, please feel free to contact us for more information or to schedule an appointment.