Both of these conditions are caused by structural distortions within the eye.
In myopia, your eyes focus the image ahead of the retina. This usually occurs with an eyeball that is longer or a cornea that is steeper than normal.
In hyperopia, your eye focuses the image behind the retina. This usually occurs if your eyeball is too short or the cornea has too little curvature. With aging, the lens of the eye becomes less flexible and cannot focus as well on close objects. This condition, called presbyopia, accounts for the development of difficulty seeing near objects in most people after the age of 40.
A risk factor is something that increases your chance of getting a disease or condition. Risk factors are slightly different for the two types of vision disorders.
Having a family member with myopia increases your risk for the disorder. Also, although the evidence is conflicting, some specialists believe that chronic near work, such as iprolonged periods of reading or the daily use of a computer can increase the risk of developing myopia.
Laser epithelial keratomileusis
(LASEK)—a procedure that is quite similar to LASIK, but differs in a technique of removal of the first layer of cornea. LASEK supposedly offers benefits over the typical LASIK procedure in terms of faster healing time and decreased post-surgical pain. Those benefits have been however questioned by recent studies. More research is needed to clarify the benefits of the LASEK procedure.
Epi LASIK procedure (Epithelial laser-assisted
in situ keratomileusis
)—a hybrid procedure that combines elements of both LASEK and LASIK.
Photorefractive keratectomy (PRK)—the use of a laser to permanently reshape the cornea by removing cells on its surface (less commonly done)
Radial keratotomy (RK)—the use of microincisions to flatten the cornea (rarely done)
Intraocular lenses—in some situations, removing your native lens and possibly replacing it with an intraocular lens can help treat myopia
Post-surgical problems with healing and/or infections
Long-term complications (more than 10 years of follow-up) are unknown at this time
Most of the treatments for nearsightedness can be applied to hyperopia as well. Another common treatment is the use of reading glasses or bifocals, which are particularly useful for presbyopia. There are also collagen shrinkage (ie, conductive keratoplasty) techniques. For people undergoing cataract surgery (or refractive lens exchange surgery), intraocular lenses that correct for myopia or hyperopia
presbyopia are now available.
There are no guidelines for the prevention of myopia or hyperopia.
Gimbel HV, Penno EE, van Westenbrugge JA, et al. Incidence and management of intraoperative and early postoperative complications in 1000 consecutive laser in situ keratomileusis cases.
Harrison's Principles of Internal Medicine
Shortt AJ, Bunce C, Allan BD. Evidence for superior efficacy and safety of LASIK over photorefractive keratectomy for correction of myopia (Review).
. 2006 Nov;113(11):1897-908.
Yoo SH, Azar DT. Laser
in situ keratomileusis
for the treatment of myopia.
Int Ophthalmol Clin
Please be aware that this information is provided to supplement the care
provided by your physician. It is neither intended nor implied to be a
substitute for professional medical advice. CALL YOUR HEALTHCARE PROVIDER
IMMEDIATELY IF YOU THINK YOU MAY HAVE A MEDICAL EMERGENCY. Always seek the
advice of your physician or other qualified health provider prior to
starting any new treatment or with any questions you may have regarding a