Posts Tagged ‘Study’
The long term side effects of refractive surgery have been a concern for all patients and doctors alike. When Radial Keratotomy(RK) was being performed; there were many unknowns. Flattening the corneas with radial corneal incisions stretched the endothelial layer decreasing its’ ability to pump water out of the cornea. While most RK surgeons were not worried about the long term corneal hydration, questions did remain as to what would occur years after the procedure.
These RK patients do have corneal issues 10 plus years later. Their corneas often display a brownish line in the bottom half indicating iron left behind when the endothelial pump removes fluid from the cornea. In addition, most of these patients are far sighted with astigmatism and their prescription gets stronger later in the day. This makes it difficult to have an accurate eye glass prescription. Weakness of the cornea also increases the risk of corneal rupture when exposed to trauma.
LASIK and PRK do not flatten out the entire width of the cornea thus leaving the endothelial layer intact. This does not affect the pump or the functioning of the physiology of the corneal tissue. Therefore negative corneal changes that are displayed in RK patients should not occur in the LASIK and PRK patients.
According to an article published in the November issue of the Archives of Ophthalmology, there are no long term destructive corneal effects following LASIK and PRK. The study examined 29 myopic LASIK and PRK patients 9 years after the surgery and found them to display no abnormal changes. There was a 5.3% decrease in the endothelial cell density which corresponds to a normal cell decrease in individuals that never had the refractive procedure.
While the study did not examine far sighted post operative patients, they concluded that the results would be similar to the near sighted patients. Whereas post operative RK patients displayed corneal changes after 5 years, the LASIK and PRK patients did not show any signs after 9 years. Further studies must be conducted at longer post op intervals to fully examine the long term effects, but this initial study is very encouraging.
Dr. Jay B Stockman is a practicing doctor for http://newyorkvisionassociates.com, and a contributing expert for VisionUpdate.
Article Source:http://www.articlesbase.com/vision-articles/long-term-effects-of-lasik-and-prk-are-encouraging-1678212.html
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Found in the macula, the macular pigment (MP) consists of two pigments or carotenoids: lutein and zeaxanthin. MP is most dense in the center of the macula named fovea. Moreover, these two pigments have different concentration is different parts of the eye. Lutein makes up 67% or greater of the MP in the peripheral retina. But in the central macula, zeaxanthin is the majority that it accounts for up to 75% of the MP.
MP in the eyes can protect them from harmful effects or free radicals caused by excessive exposure to UV rays and blue light. In detail, the two pigments of MP can help prevent age-related macular degeneration. In general, there are two ways to get enough lutein and zeaxanthin. A balanced diet with plenty of green vegetables and fruits as well as dietary supplements of the two nutrients can both offer enough MP.
As supplements are one of the main sources of MP, there are many studies focusing on these supplements as well as their effects. One study named enhancement of macular pigment density by oral lutein supplement (EMPOLS) conducted by researchers in Berne, Switzerland evaluates the relation between MP density and intake of supplements containing lutein. Participants of this study consume 10mg of lutein supplement product labeled VitaluxPlus on a daily basis.
Another observation study named the role of macular pigment in patients with age-related macular degeneration is also being carried out in Switzerland. Expected to complete in December 2009, this study has several purposes. First one is to assess how MP density and its distribution are associated with age-related macular degeneration. A second aim is to identify patients with low MP density. The study is still supposed to improve the early diagnosis of patients susceptible to AMD. Since low MP values are high risks of AMD, the observation study will develop a basis for dietary supplementation of lutein and zeaxanthin.
A balanced diet beneficial to eye health should contain many foods. Lutein is one of the critical elements. Many sources are rich in lutein, including corn, eggs, spinach, carrots, cantaloupe, oranges, red and orange peppers, kale, and collard greens and so on. In order to facilitate the absorption of lutein through the digestive tract, it is also necessary to eat some healthy fat in combination with those raw vegetables.
More related articles
·AMD treatments that are under trials and researches
·FDA-approved treatments for AMD
·Various ways to prevent AMD
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Article Source:http://www.articlesbase.com/vision-articles/mp-density-and-amd-1534204.html
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The use of contact lenses in place of eyeglasses has got a currency – is the present phenomenon. While the adults or matures can grasp this advantage, why should children lack behind?
Yea, resent studies have opened this envelope and shows that children are also able to take the option of contact lens in spite of heavy spectacles.
There was a time when an optometrist will prescribe contact lenses until they reach 12 years or older than that. But recent study at Ohio State University of 169 children tallied the use of contact lenses in children of 8 to 12 years and children of 13 to 17. The project named the contact lens in pediatrics (CLIP) study, and the outcome proved younger children including those of 8 to 12 were competent and able to use contact lens as the later group (children of 13 to 17). This study ascertains the results of a previous study, which proposes that children between the ages of 8 and 12 are able to handle certain fixed types of contact lens. None of the participants ever used contact lenses before the experiment by the researchers. They are provided a plan with a three-month supply of soft disposable contact lenses and in doing so researchers offer them a complete guideline of how to use lenses on their eyes. When results came out children were more satisfied with contact lenses. When they ere questioned about its quality and its distinction with eyeglasses. They simply retorted ‘wearing contact lenses instead of eyeglasses may have a higher self-esteem”. Some of them enhanced the importance of contact lenses, opined that contact lenses give them the potentiality to engage in everyday activities and sports, giving them more ease. A child’s vision often tends to change fast. The mainstream is children of 8 years and older seem capable of maintaining contact lenses and able to wear them properly. Contact lenses have got the license for the children who are eager to grasp their future not through peepshow of indistinct, monotonous, spectacles but via the transparent, lucid and straight contact lenses. Some children who are suffering from ‘astigmatism’ or other eye-oriented diseases shall be benefited by the use of monofocal or multifocal installation of contact lenses. The contact lenses in other cases can cure to certain extent your vision problems. If you are bored while working with your spectacles, then contact lenses can give you all the comforts and you should never fatigue while toiling at office or home. You can assure yourself as safe from the UV rays (Ultra Violet Rays) of the sun, which is supposed to harm the portion of your cataracts of your eye and can bring eternal blindness. Wearing ‘blue’ tint contact lens should provide you a good complexion in your personality or even in your own individuality. Thus using contact lenses can change your lifestyle and in broader way change your life’s preface as a whole. Not only you can taste this new fruit of this research but also your child can gain a proper freedom to visualize the entire beautiful world with those beautiful lenses. So are you ready for contact lenses?
Get the best place to buy contact lenses is Contact Lense Compared where you can find the best quality contact lenses at a reasonable range.
Article Source:http://www.articlesbase.com/vision-articles/a-passport-for-all-contact-lenses-1435737.html
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Although many people worry about the long-term stability of the results they get with LASIK or other refractive procedures, recent studies are showing that the results of LASIK are indeed stable over the long term and lead to most people experiencing satisfaction with their vision for many years after receiving treatment. According to one study, about 88% of people who get refractive surgery have as good or better vision 12 years after, and another study shows that nearly 85% of people are satisfied with their vision correction 14 years after surgery.
A Lack of Long-Term Data
In 2006, an editorial in the Journal of Refractive Surgery pointed out that no-one had published a significant study of 10-year safety data on LASIK. This article pointed out that if the officially acknowledged complication rates were true, then the number of people who experienced some complications would be 23-75 times more than actually observed. The lack of published results was touted as “no news is good news,” but also used as a call to surgeons to publish their actual complication rates to educate the public about the safety of laser vision correction.
Supplying the Lack
In the same issue of the Journal of Refractive Surgery, a 12-year follow-up of a small population of laser vision correction recipients. The study compared 2-year results of an initial population of 80 patients (120 eyes) to 34 patients (58 eyes) that returned after 12 years. According to the study, 87.9% of eyes had maintained their vision, and 34.5% of them had actually gained one line of visual acuity. 67% of eyes had uncorrected visual acuity of ?20/20. Complications noted were a trace haze in 17.2% of eyes, and night vision problems in 41% of eyes. Night vision problems were only considered severe in 2.7% of eyes.
More recently, a study published in the June 2009 issue of the Journal of Refractive Surgery shows the results of a survey of refractive surgery recipients over 14 years after receiving surgery. This survey included 31 patients (49 eyes) who had surgery between 1991 and 1993. The patients were divided into two groups: those who had surgery for low myopia and those who had surgery for high myopia. Among the low myopia group, 84% were still satisfied with their vision, and among the high myopia group 75% were satisfied.
Significant Data Still Needed
Unfortunately, these two studies are typical of reported results. A small number of studies exist focusing on the long-term safety of refractive surgeries like LASIK, and those that exist focus on a very small number of patients and eyes. With millions of procedures being performed every year, there should be plenty of raw material for studies. Why are ophthalmologists not performing these studies and publishing their results?
Faced with anecdotal reports of severe complications and negative outcomes, the Food and Drug Administration has decided to take matters into its own hands. It is currently performing investigations into the long-term safety and complication rates of LASIK and other refractive surgeries and may soon publish new guidelines.
In the meantime, your best method of reducing your risk of complications related to LASIK or other refractive surgeries is to work with an experienced doctor utilizing advanced technology. For more information, please consult the website of 20/20 Institute with offices in Denver, Indianapolis and Portland.
Article Source:http://www.articlesbase.com/vision-articles/refractive-vision-surgery-gives-longterm-stable-results-1369435.html
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Los Angeles Lasik center Maloney Vision Institute is hosting an FDA study on the ACI Corneal Inlay, which is an implant that can reduce the need for reading glasses.
Understanding the loss of near vision.
A healthy, young eye is able to focus light from both far and near objects to create a clear image at all distances. By age 45, the eye’s natural lens is too stiff to focus on near points. As a result, near tasks like reading or computer work are blurry. This is a natural occurrence that affects us the rest of our life. The clinical term for the loss of near vision is presbyopia. It is possible to have poor near vision, but good distance vision, especially if you have already had Los Angeles Lasik surgery to correct this.
Buying a pair of reading glasses is a quick way to improve near vision. While “readers” will help you read a book or dial a telephone number, they will not help you see far objects. Some find putting glasses on to see near and taking off to see far inconvenient.
The ACI Corneal Inlay no-cost research study.
Smaller than a contact lens, the ACI Corneal Inlay looks like a black ring. There is a tiny aperture or hole in the center of the inlay. The inlay can help vision correction Los Angeles patients in two ways.
1. Creates a pinhole effect so near objects are clearer.
2. Focuses light rays so you can see a wider range of vision – near, intermediate (computer) and distance. During an out-patient procedure, the research doctor will implant the inlay in one eye. If needed, the ACI Corneal Inlay can be surgically removed.
You may be eligible to participate in the study if you are…
- Between the ages of 45 and 60.
- Using reading glasses to read or work on the computer.
- Not using glasses or contacts to see far objects – Lasik Los Angeles patients are welcome.
- In good physical health.
- Able to meet other medical criteria determined by the research doctor.
Improvement in near vision.
The amount of time it takes to see an improvement in near vision varies. Some see better in a few days. For others, it takes several months, or there may be no improvement at all.
You can help your eye heal faster by using eye drops as prescribed. You will also be asked to practice reading without glasses. This activity will help train your inlay eye how to see near again.
Next steps.
If you are interested in learning if the ACI Corneal Inlay can reduce your dependence on reading glasses, contact Maloney Vision Institute by telephone 310.208.3937 or email info@maloneyvision.com . You can also visit www.NearVisionStudy.com for more information.
The information about the ACI Corneal Inlay clinical research study is not intended to provide medical advice. Always consult your doctor for medical advice and treatment.
Caution: Investigational device. Limited by United States federal law to investigational use.
Dr. Robert Maloney ABC’s extreme makeover doctor, performed over 50,000 lasik surgery. Los angeles best laser eye center, voted top 10 in USA. For more details visit us : http://www.maloneyvision.com/
Article Source:http://www.articlesbase.com/vision-articles/maloney-vision-institute-seeks-participants-for-research-study-on-reducing-the-dependence-on-reading-glasses-1301855.html