Many types of vision problems exist. The common ones are myopia, hyperopia, astigmatism, and presbyopia. The following defines what each problem is:
Myopia
Affected patients have difficulty focusing on objects at a distance. Compelled to wear glasses or contact lenses, patients have difficulty in performing day to day tasks, especially driving. Myopia can manifest in one eye or both eyes. The affected eye’s cornea is steeper, which causes light to focus in front of the retina. The corrective procedure is to make the eye focus light on the retina.
Hyperopia
Patients affected with farsightedness have difficulty focusing on or seeing objects at close range. The farsighted eye’s dimension is shorter, with a flatter cornea, than a normal eye. The distorted eye shape causes light entering into the eye to focus behind the retina. The corrective procedure is to make the eye focus light on the retina.
Astigmatism
Changed corneal shape causes astigmatism. A steep cornea causes light entering into the eye to be projected irregularly on the retina. The patient experiences blurred vision. Astigmatism is commonly associated with some other refractive error. A laser eye surgery from a premier clinic such as Sugarland Eye & Laser Center in Houston corrects both these problems.
Presbyopia
This condition may commonly affect people above the age of 45. The gradual thickening of the lens, and its reducing flexibility, can cause a decrease in the eyes’ focusing abilities. Patients are constrained to using reading glasses and bifocals. When both eyes are affected, LASIK Monovision can correct one eye for nearsightedness and the other for farsightedness. This way, the patient can gradually adjust to seeing and focusing on near and far objects.
Understanding eyeglass prescription
The first step is to understand the two abbreviations – OD and OS. The former is Oculus Dexter and the latter is Oculus Sinister. Both these terms are Latin words for right eye and left eye respectively. If the eye prescription is for both eyes, the OU is used which reads as Oculus Uterque, or for both eyes. Some doctors may not use these abbreviations. They may use RE and LE to denote right eye and left eye instead.
The following is an example of a prescription:
OD -2.00 SPH +2.00 add 0.5 p.d. BD
OS -1.00 -0.50 x 180 +2.00 add 0.5 p.d. BU
The prescription indicates that -2.00 sphere for correction of nearsightedness is prescribed for the right eye. SPH indicates spherical power, for which the doctor has prescribed to increase it in the right eye. The left eye is prescribed for nearsightedness treatment with a measure of -1.00 sphere. The -0.50 D cylinder indicates rectification of astigmatism.
Conclusion
No harm exists in asking the eye doctor to explain the constituents of an eye glass prescription. It helps in understanding the gravity of the eye problem. Sometimes, as per doctors themselves, self-help is the best help. Additionally, knowledge of prevention and eye care goes a long way in preventing eye conditions.
Sugarland Eye & Laser Center leads in providing premium LASIK technologies to Houston, Sugar Land, and the surrounding region. The Center’s award-winning medical director introduced revolutionary technologies such as iLASIK to the region. This technology is used by NASA astronauts, Navy SEALS and Air Force fighter pilots. At Sugarland Eye & Laser Center, you can now receive the same treatment. For more information, please call (281) 240-0478 or visit us at www.houston-lasik.com.
About the Author
Amjad Khokhar, M.D. is Chief LASIK Surgeon at Sugarland Eye & Laser Center. Add Dr. Khokhar on Google+ here.
Via:
http://www.allaboutvision.com/eyeglasses/eyeglass-prescription.htm
http://www.clearsight.com/oklahoma/learn-about-lasik/what-can-lasik-correct.htm
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