Refractive Errors (Print Version)

Also called: Also called: Farsightedness, Hyperopia, Myopia, Nearsightedness

Your cornea is the clear front part of your eye. It is like a window that controls and focuses the light coming into the eye. If your cornea has an irregular shape, the light does not focus properly. Everything looks blurry. This is a refractive error.

Four common refractive errors are

Myopia, or nearsightedness - clear vision close up but blurry in the distance
Hyperopia, or farsightedness - clear vision in the distance but blurry close up
Presbyopia - inability to focus close up as a result of aging
Astigmatism - focus problems caused by the cornea

Glasses or contact lenses can usually correct refractive errors. Laser eye surgery may also be a possibility.

National Eye Institute

Start Here

Questions and Answers about Refractive Errors(National Eye Institute) - http://www.nei.nih.gov/CanWeSee/qa_refractive.asp
Also available in Spanish http://www.nei.nih.gov/CanWeSee/qa_refractive_span.asp
Refractive Errors(American Academy of Ophthalmology) - http://www.eyecareamerica.org/eyecare/conditions/refractive-errors/index.cfm

Overviews

Focus on Vision(Food and Drug Administration) - http://www.fda.gov/fdac/features/2006/406_vision.html

Latest News

Half of U.S. Adults Lack 20/20 Vision(08/11/2008, HealthDay) - http://www.nlm.nih.gov/medlineplus/news/fullstory_68024.html

Treatment

Cornea Transplants: Restoring Sight with Donor Tissue(Mayo Foundation for Medical Education and Research) - http://www.mayoclinic.com/print/cornea-transplant/EY00004/METHOD=print
Corneal Modifications(American Optometric Association) - http://www.aoa.org/corneal-modifications.xml
Learning about Phakic Intraocular Lenses(Food and Drug Administration) - http://www.fda.gov/cdrh/phakic/
MedlinePlus: Laser Eye Surgery(National Library of Medicine) - http://www.nlm.nih.gov/medlineplus/lasereyesurgery.html
Also available in Spanish http://www.nlm.nih.gov/medlineplus/spanish/lasereyesurgery.html
Other Refractive Surgeries(Eye Surgery Education Council) - http://www.eyesurgeryeducation.com/Other_Refractive.html
Refractive Surgery(American Academy of Ophthalmology) - http://www.medem.com/medlb/article_detaillb.cfm?article_ID=ZZZ04IBZLDE&sub_cat=0
Refractive Surgery: What Are the Risks and How Can I Find the Right Doctor for Me?(Food and Drug Administration) - http://www.fda.gov/cdrh/lasik/risks.htm

Prevention/Screening

Distance Vision Test For Adults(Prevent Blindness America) - http://www.preventblindness.org/eye_tests/Adult_distance_test.html
Eye Exams: What to Expect(Foundation of the American Academy of Ophthalmology) - http://www.eyecareamerica.org/eyecare/treatment/eye-exams.cfm
Near Vision Test For Adults(Prevent Blindness America) - http://www.preventblindness.org/eye_tests/near_vision_test.html

Specific Conditions

Astigmatism(Mayo Foundation for Medical Education and Research) - http://www.mayoclinic.com/print/astigmatism/DS00230/DSECTION=all&METHOD=print
Eye Coordination(American Optometric Association) - http://www.aoa.org/x4703.xml
Facts about the Cornea and Corneal Disease(National Eye Institute) - http://www.nei.nih.gov/health/cornealdisease/
Farsightedness(Mayo Foundation for Medical Education and Research) - http://www.mayoclinic.com/print/farsightedness/DS00527/DSECTION=all&METHOD=print
Nearsightedness (Myopia)(Mayo Foundation for Medical Education and Research) - http://www.mayoclinic.com/print/nearsightedness/DS00528/DSECTION=all&METHOD=print

Related Issues

Eye Care Facts and Myths: A Closer Look(American Academy of Ophthalmology) - http://www.medem.com/medlb/article_detaillb.cfm?article_ID=ZZZ8BUZTYIE&sub_cat=0
Selecting a Refractive Eye Surgeon(Eye Surgery Education Council) - http://www.eyesurgeryeducation.com/Selecting_Surgeon.html
Visual Acuity: What Is 20/20 Vision?(American Optometric Association) - http://www.aoa.org/x4695.xml

Pictures & Photographs

Eye Examinations(National Eye Institute) - http://www.nei.nih.gov/photo/keyword.asp?conditions=Eye+Exams
Presbyopia(Logical Images) - http://www.visualdxhealth.com/adult/presbyopia.htm

Videos

Astigmatism(American Optometric Association) - http://www.aoa.org/x4698.xml
Hyperopia (Farsightedness)(American Optometric Association) - http://www.aoa.org/x4696.xml
Myopia (Nearsightedness)(American Optometric Association) - http://www.aoa.org/x4688.xml
Presbyopia(American Optometric Association) - http://www.aoa.org/x4697.xml

Anatomy/Physiology

Diagram of the Eye(National Eye Institute) - http://www.nei.nih.gov/health/eyediagram/
Also available in Spanish http://www.nei.nih.gov/health/espanol/diagrama_ojo.asp

Financial Issues

Financial Aid for Eye Care(National Eye Institute) - http://www.nei.nih.gov/health/financialaid.asp
Also available in Spanish http://www.nei.nih.gov/health/espanol/financialaid_sp.asp

Clinical Trials

ClinicalTrials.gov: Astigmatism(National Institutes of Health) - http://clinicaltrials.gov/search/open/condition=%22Astigmatism%22
ClinicalTrials.gov: Hyperopia(National Institutes of Health) - http://clinicaltrials.gov/search/open/condition=%22Hyperopia%22
ClinicalTrials.gov: Myopia(National Institutes of Health) - http://clinicaltrials.gov/search/open/condition=%22Myopia%22
ClinicalTrials.gov: Refractive Errors(National Institutes of Health) - http://clinicaltrials.gov/search/open/condition=%22Refractive+Errors%22

Journal Articles

References and abstracts from MEDLINE/PubMed (National Library of Medicine)

Article: Effects of lotrafilcon A and omafilcon A bandage contact lenses... - http://www.ncbi.nlm.nih.gov/sites/entrez?cmd=Retrieve&db=pubmed&dopt=AbstractPlus&list_uids=18655978&tool=MedlinePlus
Article: Clinical outcomes of laser in situ keratomileusis using combined topography... - http://www.ncbi.nlm.nih.gov/sites/entrez?cmd=Retrieve&db=pubmed&dopt=AbstractPlus&list_uids=18655973&tool=MedlinePlus
Article: Intravitreal bevacizumab (Avastin) for choroidal neovascularisation secondary to pathological myopia:... - http://www.ncbi.nlm.nih.gov/sites/entrez?cmd=Retrieve&db=pubmed&dopt=AbstractPlus&list_uids=18653595&tool=MedlinePlus
Refractive Errors -- see more articles - http://www.ncbi.nlm.nih.gov/sites/entrez?cmd=search&db=pubmed&term=myopia[majr]+AND+humans[mh]+AND+english[la]+AND+(review[pt]+OR+guideline[pt]+OR+clinical+trial[pt]+OR+jsubsetk[text]+OR+patient+education+handout[pt])+NOT+(letter[pt]+OR+editorial[pt])&doptcmdl=summary&cmd_current=Limits&pmfilter_EDatLimit=last+1+Year&tool=MedlinePlus
Astigmatism -- see more articles - http://www.ncbi.nlm.nih.gov/sites/entrez?cmd=search&db=pubmed&term=astigmatism[majr]+AND+humans[mh]+AND+english[la]+NOT+(letter[pt]+OR+editorial[pt])&doptcmdl=summary&cmd_current=Limits&pmfilter_EDatLimit=last+1+Year&tool=MedlinePlus
Farsightedness (hyperopia) -- see more articles - http://www.ncbi.nlm.nih.gov/sites/entrez?cmd=search&db=pubmed&term=hyperopia[majr]+AND+humans[mh]+AND+english[la]+NOT+(letter[pt]+OR+editorial[pt])&doptcmdl=summary&cmd_current=Limits&pmfilter_EDatLimit=last+1+Year&tool=MedlinePlus

Dictionaries/Glossaries

Eye Surgery Glossary(Eye Surgery Education Council) - http://www.eyesurgeryeducation.com/Glossary.html

Directories

Eye Health Organizations Database(National Eye Institute) - http://www.nei.nih.gov/health/resourceSearch.asp
Find a Pediatric Ophthalmologist(American Association for Pediatric Ophthalmology and Strabismus) - http://aapos.affiniscape.com/associations/5371/aapos_search.cfm
Find an Eye M.D.(American Academy of Ophthalmology) - http://www.aao.org/aao/eyemd_disclaimer.cfm
Find an Optometrist(Association of Regulatory Boards of Optometry) - http://www.arbo.org/index.php?action=findanoptometrist
Finding an Eye Care Professional(National Eye Institute) - http://www.nei.nih.gov/health/findprofessional.asp
Also available in Spanish http://www.nei.nih.gov/health/espanol/findpro_sp.asp

Organizations

American Academy of Ophthalmology - http://www.aao.org/
American Optometric Association - http://www.aoa.org/
National Eye Institute - http://www.nei.nih.gov/
Prevent Blindness America - http://www.preventblindness.org/

Children

Common Eye Problems in Children(Prevent Blindness America) - http://www.preventblindness.org/children/ch_eye_problems.html
Glasses and Contact Lenses(Nemours Foundation) - http://kidshealth.org/kid/stay_healthy/body/glasses.html
Home Eye Tests For Children(Prevent Blindness America) - http://www.preventblindness.org/children/children_eye_tests.html
Your Child's Vision(Nemours Foundation) - http://kidshealth.org/parent/general/eyes/vision.html
Also available in Spanish http://kidshealth.org/parent/en_espanol/general/vision_esp.html

Seniors

Presbyopia(Mayo Foundation for Medical Education and Research) - http://www.mayoclinic.com/print/presbyopia/DS00589/DSECTION=all&METHOD=print

You may also be interested in these MedlinePlus related pages:

Eye Wear - http://www.nlm.nih.gov/medlineplus/eyewear.html
Laser Eye Surgery - http://www.nlm.nih.gov/medlineplus/lasereyesurgery.html
Vision Impairment and Blindness - http://www.nlm.nih.gov/medlineplus/visionimpairmentandblindness.html
Eyes and Vision - http://www.nlm.nih.gov/medlineplus/eyesandvision.html

The primary NIH organization for research on Refractive Errors is the National Eye Institute - http://www.nei.nih.gov/