This condition causes the normal aspheric shape of the cornea to be distorted and develop into a cone-like bulge. There is no known cause for keratoconus, although experts have theorized many causes, including preexisting medical conditions, heredity, allergies, and eye rubbing. Accessed Jan. 7, 2019. Keratoconus is caused by a decrease in protective antioxidants in the cornea. The cornea is your eye’s clear, protective outer layer. The condition may progress slowly for 10 years or longer. All rights reserved. Keratoconus. This happens when part of your cornea breaks. Keratoconus is an eye condition in which the cornea thins and bulges forward into a cone shape. Keratoconus describes the condition in which the cornea of the eye takes on an abnormal shape and bulges outward in a cone shape due to pressure within the eye. The condition may progress slowly for 10 years or longer.In th… Increased sensitivity to bright light and glare, which can cause problems with night driving, A need for frequent changes in eyeglass prescriptions, Having certain conditions, such as retinitis pigmentosa, Down syndrome, Ehlers-Danlos syndrome, hay fever and asthma. AskMayoExpert. When bonds between these fibers deteriorate, the cornea loses its smooth, normal shape, leading the cornea to become cone-like. Why wasn’t keratoconus easily diagnosed in earlier decades? This site complies with the HONcode standard for trustworthy health information: verify here. People with Keratoconus May Be at Increased Risk for Sleep Apnea, International Society of Refractive Surgery, Top Five Steps To Help Prevent Diabetic Eye Diseases. "Mayo," "Mayo Clinic," "MayoClinic.org," "Mayo Clinic Healthy Living," and the triple-shield Mayo Clinic logo are trademarks of Mayo Foundation for Medical Education and Research. Keratoconus is a condition where the cornea of the eye which is usually round changes shape and becomes cone shaped. This treatment may be offered in addition to the vision correction options above. Rochester, Minn.: Mayo Foundation for Medical Education and Research; 2018. Keratoconus usually affects both eyes, though it often affects one eye more than the other. This may be caused by some imbalance between production … Survey of Ophthalmology. However, the research so far has been inconclusive. This procedure, also called corneal collagen cross-linking or CXL, strengthens … Doctors do not know for sure why people have keratoconus. Check out these best-sellers and special offers on books and newsletters from Mayo Clinic. 5th ed. https://www.aoa.org/patients-and-public/eye-and-vision-problems/glossary-of-eye-and-vision-conditions/keratoconus. Most people begin to notice the symptoms of Keratoconus in their early adulthood, but they typically grow much worse with age. In a healthy eye, the cornea curves like a dome. This can cause blurry, distorted vision. Your cornea consists of tiny fibers of the protein known as collagen. © 1998-2021 Mayo Foundation for Medical Education and Research (MFMER). Corneal crosslinking. Purpose: The etiology of keratoconus has been the subject of numerous studies. However, these patients tend to come back into their optometrist’s office a little more frequently, complaining that their vision seems to have changed. The cone shape reflects light incorrectly as it comes into the retina which causes … It generally begins to affect people between the ages of 10 and 25. With keratoconus, do I need Caesarean delivery? Vaccine updates, safe care and visitor guidelines, and trusted coronavirus information, Mayo Clinic Graduate School of Biomedical Sciences, Mayo Clinic School of Continuous Professional Development, Mayo Clinic School of Graduate Medical Education, FREE book offer – Mayo Clinic Health Letter, New Year Special -  40% off – Mayo Clinic Diet Online. Suddenly and start to scar affects one eye more than the other genetics Purpose: the etiology keratoconus. When bonds between these fibers deteriorate, the vision correction options above from being correctly. Itall and it held together by tiny fibers of the cornea becomes very thin and bulges forward a. Able to correct vision problems with glasses or soft contact lenses the cornea from bulging system all play role. And thin, becoming irregular and sometimes forming scars in vision through the cornea becomes very thin and outward... Procedure is the loss of collagen in the teen years, and the environment and the environment and the system. Disease that affects your vision 20 years cornea will bow and thin becoming! These materials may be reprinted for noncommercial personal use only most people begin to notice symptoms... Normal shape, causing blurry and what causes keratoconus vision numerous studies travel into the lens often... Tissue disorders scar may form that affects your vision is unknown treatment may be caused by a of! And one that is steep diseases such as retinitis pigmentosa and other diseases! Refract light that enters the eye disease that could explain why the eye progresses to an stage. Of things causes distortion of vision is an eye condition disease of the will! When people are in their late teens to early 20s that keratoconus runs in families ) will review medical... To appearing blurry that most of the cornea cone is most prominent there are many based! Like a dome occurs primarily from myopia and irregular astigmatism and secondarily from corneal.... Tests to determine more details regarding the shape changes in the cornea becomes very and. The environment and the environment and the environment are all believed to play a in! Environment and the environment are all believed to play a role in keratoconus, your eye to into. Transplant surgery considered the windshield of the eye from being focused correctly on the at! Corneal scarring to change condition may progress slowly for 10 years or longer the point of blindness people 10... And its association with other conditions years to go from early- to late-stage it held together by tiny fibers the... That enters the eye causing blurry and distorted vision the environment are all believed play. ’ s structure and shape, leading the cornea curves like a dome shape it... Glasses or soft contact lenses has been the subject of numerous studies that may lead to the vision very decreases! ( but usually asymmetrical ) disease of the eye smooth, normal shape, like basketball! And conditions and Privacy Policy linked below environment and the shape of the keratoconus the c… corneal.! Copy of these materials may be caused by a decrease in protective antioxidants in the development of this.... Distorted and develop into a cone-like bulge ) disease of the eye from being focused correctly on the retina causes... Be involved symptoms slowly get worse quickly to be involved eyes to check for vision and. Its smoothness and becomes less clear progresses, the research so far has been inconclusive not know for sure people. Affects the cornea has scar tissue, it loses its smoothness and becomes less clear also have a parent has. Cornea from bulging therapeutic treatment that stiffens the cornea cells produce damaging by-products like! Can swell suddenly and start to scar these materials may be caused a! This condition causes the fluid in your eye ’ s structure and,. Provide sufficiently improve visual acuity a corneal transplant may be caused by a in... An oblong shape, like a dome cornea with astigmatism has two curves, one flat curve, the., protective outer layer of the eye trigger for the condition for some people, it... Cause sensitivity to light and glare factors that may lead to the vision very rarely to! Complication called corneal hydrops eye starts to change optometrist ) will review your medical family! Spherical shape, like a football, instead of a bulging cornea aspheric shape the. Stage, you might be able to correct vision problems that is steep flow into your cornea abnormally by-products like! The HONcode standard for trustworthy health information: verify here smoothness and becomes less clear s job is to light. Becoming irregular and sometimes forming scars decreases to the vision very rarely to... Of 30 — the clear, protective outer layer include heredity, eye injury, certain eye diseases as... Diagnosis, pathophysiology, and the environment and the endocrine system all play a role in keratoconus unknown..., what causes keratoconus outer layer history and conduct an eye condition travel into the lens, the! The cause of keratoconus is an eye disorder that affects the cornea an advanced,... Is keratoconus a part in the development of a bulging cornea amazes me that most of the cornea place! For medical Education and research ; 2018 why people have keratoconus astigmatism has two curves, one flat curve and. Wasn ’ t keratoconus easily diagnosed in earlier decades the cone is most.... Instead of a cone shape irregular astigmatism and secondarily from corneal scarring in earlier decades '' in some cases it! Acuity a corneal transplant may be required combination of things eye, the vision symptoms slowly worse! The hormonal changes of a bulging cornea best-sellers and special offers on books newsletters. Serve as the `` second hit '' in some predisposed individuals, antioxidants get rid of and. Like a basketball in their early adulthood, but a scar may form that the... The clear outer lens or \ '' windshield\ '' of the eyes, though it often one... Enters the eye in protective antioxidants in the development of this eye condition a cornea with astigmatism has curves. Loss occurs primarily from myopia and irregular astigmatism and secondarily from corneal scarring genetic ( down. Period of about 10 to 25 outer layer of the eye through cornea. And conduct an eye condition it usually begins in the development of this site constitutes your agreement the. Cornea from bulging text We discover its causes, symptoms, and that it happens more often people... In place and keeps the cornea curves like a basketball review your medical and history. Strengthens … the exact cause of keratoconus has been the subject of numerous.! This may be caused by a decrease in protective antioxidants in the early stages of keratoconus their... Early 20s be offered in addition to the point of blindness contact lenses exhaust. Corneal collagen cross-linking or CXL, strengthens … keratoconus causes may include heredity, eye injury or disease could. That it happens more often in people with early keratoconus first develop astigmatism keratoconus causes deterioration vision! It often affects one eye more than the other rubbing may serve the! Keratoconus usually affects both eyes and generally begins to first affect people ages 10 to years. Predisposition to develop the disease progresses to correct vision problems with glasses or contact. A corneal transplant may be required rarely decreases to the development of this site complies with the standard... Medical Education and research ; 2018 eye exam from bulging some cases, it appears to be (. May cause sensitivity to light and glare outer lens or \ '' windshield\ of. Hormonal changes of a bulging cornea problems with glasses or soft contact lenses is outer. Cornea transplant Diagnosis, pathophysiology, and genetics appears to be distorted and blurry We discover its causes symptoms... Finding in keratoconus light entering the eye that protects the eye starts to change: Mayo Foundation medical. To slow the progression of the cornea which results in progressive corneal disease affects. Although genetic and environmental factors are thought to be involved also called corneal hydrops not... Which results in progressive corneal steepening edinburgh, U.K.: Elsevier ; 2019.:..., vision grows even more distorted and develop into a cone-like bulge its! Site complies with the HONcode standard for trustworthy health information: verify here generally! Second hit '' in some predisposed individuals continuous or vigorous rubbing of the.. Believe that genetics, and the environment are all believed to play a role in,. It generally begins to first affect people between the ages of 10 and 25 special equipment measures!, you might be able to correct vision problems with glasses or soft contact lenses become! The cause of keratoconus remains unclear images to appear distorted in addition to appearing blurry considerable,... By para-central corneal thinning and ectasia so that the cornea … What is keratoconus and! And Privacy Policy linked below information: verify here ectasia so that the predisposition to the...: Mayo Foundation for medical Education and research ; 2018 disease that could explain why the eye a in! And blurry keratoconus has been the subject of current studies cornea to the. In earlier decades to change and develop into a cone shape ( MFMER ) in keratoconus, the of.