A cataract is a clouded or opaque area over the lens of the eye—an area that is normally transparent. As this thickening occurs, it prevents light rays from passing through the lens and focusing on the retina, which is light sensitive tissue lining the back of the eye. This clouding occurs when some of the protein which makes up the lens begins to clump together and interferes with vision.

cataract vision
Normal Vision Cataract

In its early stages, a cataract may not cause a problem. The cloudiness may affect only a small part of the lens. However, the cataract may grow larger over time and affect more of the lens. As less light reaches the retina, it becomes increasingly harder to see and vision may become dull and blurry. While cataracts cannot spread from one eye to another, many persons develop cataracts in both eyes.


Although scientists do not know for sure what causes cataracts, they suspect there could be several possible causes including:

  • Smoking
  • Diabetes
  • Excessive exposure to sunlight
  • Steroid use
  • Diuretic use
  • Certain major tranquilizers

For several of the potential causes listed (i.e., steroids, diuretics, and/or major tranquilizers), additional research is needed to differentiate the effect of the disease from the effect of the drugs themselves.


The following are the most common symptoms of cataracts. However, each individual experiences cataracts differently. Symptoms may include:

  • Cloudy or blurry vision
  • Lights that appear too bright and/or present a glare or a surrounding halo
  • Poor night vision
  • Multiple vision (i.e. double vision)
  • Colors that seem faded
  • Increased nearsightedness, increasing the need to change eyeglass prescriptions
  • Distortion of vision in either eye

Often in the disease's early stages, you may not notice any changes in your vision. Since cataracts tend to grow slowly, vision usually worsens gradually. Certain cataracts can also cause a temporary improvement in close-up vision, but this is likely to worsen as the cataract grows. The symptoms of cataracts may resemble other eye conditions. Consult a physician for diagnosis.


In addition to a complete medical history and eye examination, diagnostic procedures for cataracts may include:

  • Visual acuity test - The common eye chart test (see below), which measures vision ability at various distances.
  • Pupil dilation - The pupil is widened with eye drops to allow a close-up examination of the eye's retina.

Other tests may also be performed to help your eye care professional learn more about the health and structure of your eye.


Specific treatment for cataracts will be determined by your physician based on:

  • Your age, overall health, and medical history
  • Extent of the disease
  • Expectations for the course of the disease
  • Your opinion or preference
  • Your tolerance for specific medications, procedures, or therapies

In its early stages, vision loss caused by a cataract may be treated with different eyeglasses, a magnifying glass, or stronger lighting. When these are no longer helpful, surgery is the only effective treatment available for most individuals. It is important to note that a cataract only needs to be removed when vision loss interferes with everyday activities such as driving, reading, or watching television. You and your doctor can make that decision together.

Risk Factors

Possible risk factors for cataracts include:

  • Age - Probably the greatest risk factor for cataracts is age. Although age-related cataracts may develop between 40 and 50 years old, vision is usually not affected greatly until after age 60.
  • Geographic location - Recent studies have shown that people who live in high altitudes are more at risk for developing cataracts.
  • Excessive sun exposure - People who spend more time in the sun may develop cataracts earlier. The American Academy of Ophthalmology now recommends wearing sunglasses and a wide brimmed hat to lessen exposure to ultraviolet rays.

Balamurali K. Ambati, M.D., Ph.D.

Dr. Bala Ambati specializes in cataract extraction, lifestyle lens implants, LASIK, cornea transplants, keratoprosthesis (artificial cornea), PRK, and other complex procedures of the cornea and anterior segment of the eye at the John A. Moran Eye Center, University of Utah, Salt Lake City. He joined the Moran faculty as a physician and researcher i... Read More

William R. Barlow, Jr., M.D.

Dr. Barlow is an experienced comprehensive ophthalmologist and ocular surgeon with a specific interest in cataract and refractive surgery. He has experience performing complex cataract surgery, femtosecond laser cataract surgery, and refractive surgeries, such as LASIK, PRK, ICL, and clear lens extraction using premium intraocular lens technologi... Read More

Craig J. Chaya, M.D.

Craig J. Chaya, MD, practices comprehensive ophthalmology with a focus on the medical and surgical management of routine/complex cataracts and glaucoma at the John A. Moran Eye Center, University of Utah, Salt Lake City. He also practices at Moran’s clinics at the Redwood Health Center and Midvalley Health Center. He is an Assistant Clinical Profes... Read More

Alan S. Crandall, M.D.

Alan S. Crandall focuses on the medical and surgical management of glaucoma and cataracts, as well as complicated anterior segment surgery. Dr. Crandall has experience with trabeculoplasty and laser cyclophotocoagulation. He is involved in numerous clinical research studies at the Moran Eye Center. Dr. Crandall lectures all over the world and was... Read More

Bradley J. Katz, M.D., Ph.D.

Bradley Katz, MD, PhD, provides medical and surgical care of eye conditions including cataract, glaucoma, diabetes, and macular degeneration at the John A. Moran Eye Center, University of Utah, Salt Lake City. He specializes in neuro-ophthalmology and evaluates patients with diseases that affect the optic nerve, diseases that affect eye movements a... Read More

Amy Lin, M.D.

Amy Lin, MD, specializes in the medical and surgical treatment of corneal and anterior segment diseases at the Moran Eye Center, University of Utah, Salt Lake City, and at the Moran Eye Center at the Midvalley Health Center. Her interests include corneal transplantation, anterior segment reconstruction, cataract surgery (including advanced technolo... Read More

Nick Mamalis, M.D.

Nick Mamalis, MD, specializes in comprehensive ophthalmology including cataract and other anterior ocular surgeries at the John A. Moran Eye Center, University of Utah, Salt Lake City. Dr. Mamalis also practices at the Moran’s Midvalley Eye Center in Murray, and Redwood Health Center in West Valley. As Director of the Ophthalmic Pathology Laborat... Read More

Mark D. Mifflin, M.D.

Mark D. Mifflin specializes in the medical and surgical treatment of corneal and anterior segment eye diseases. His expertise includes all types of corneal transplantation, cataract surgery, and vision correction using lasers, intra-ocular lenses, and conductive keratoplasty. Dr. Mifflin is the Residency Program Director and Education Director for ... Read More

Randall J. Olson, M.D.

Randall J Olson is the CEO of the John A. Moran Eye Center. He is the author of more than 300 professional publications and a worldwide lecturer. Dr. Olson specializes in research dealing with intra-ocular lens complications, teleophthalmology and corneal transplantation techniques. He was selected as one of the 15 best cataract surgeons in the Uni... Read More

Jeff Pettey, M.D.

Jeff Pettey is the John Moran Eye Center's Residency Program Director and an Assistant Clinical Professor at the University of Utah Department of Ophthalmology and Visual Sciences. Dr. Pettey specializes in comprehensive ophthalmology, complex cataracts and anterior segment surgery. Additionally, he coordinates the teaching and training of medica... Read More

Geoffrey C. Tabin, M.D.

Geoffrey Tabin, M.D. is a Professor of Ophthalmology and Visual Sciences and Co-Director of the Outreach Division at the John A. Moran Eye Center and University of Utah and; specializing in cornea, cataract and refractive surgery. Dr. Tabin graduated from Yale College, earned a M.A. in philosophy at Oxford as a Marshall Scholar, and then his M.D. f... Read More

Norm A. Zabriskie, M.D.

Norm A. Zabriskie specializes in the medical and surgical treatment of glaucoma and cataracts. He is the Vice-Chairman of Clinical Operations and the Medical Director of the John A. Moran Eye Center. He has a research interest in the genetics of glaucoma.... Read More

John A. Moran Eye Center 65 Mario Capecchi Drive
Salt Lake City, UT 84132
(801) 581-2352
Midvalley Health Center 243 E 6100 S
Murray, UT 84107
(801) 585-3937
Redstone Health Center 1743 W. Redstone Center Dr.
Park City, UT 84098
(435) 658-9262
Redwood Health Center 1525 West 2100 South
Salt Lake City UT 84119
(801) 213-8841
South Jordan Health Center 5126 W. Daybreak Parkway
South Jordan, UT 84095
(801) 213-4500