Eye anatomy.
  • A cataract is an opacification of the lens of one or both eyes, which can lead to decreased visual acuity and visual distortions
  • Cataracts are most commonly due to normal age related changes, however they can also be caused by eye trauma, exposure to sunlight or radiation, malnutrition, corticosteroid use, and other pathologic processes
  • By age 80, approximately 50% of Americans have been diagnosed with one or more cataracts[1]
  • Additional risk factors for cataract include Diabetes, smoking, prolonged exposure to sunlight, and alcohol use[2][3]
  • A cataract is typically a non-emergent pathology which can be managed with outpatient ophthalmologic surgery on a routine basis.
  • With the exception of traumatic cataract, vision loss for cataract is typically not acute, and will develop over the course of months to years.

Clinical Features

The appearance of a dense, white cataract in a 60 year-old male.


  • Cloudy or blurry vision
  • Difficulty with night time vision
  • Colors appear faded
  • Appearance of a halo around bright lights
  • Recent trauma to the eye

Exam Findings

  • Lens opacity on ophthalmic examination
  • Darkening of the red reflex
  • Decreased visual acuity

Differential Diagnosis

Acute Vision Loss (Noninflamed)

Emergent Diagnosis

Subacute Vision Loss (Noninflamed)

  • Cataracts
  • Congenital blindness
  • Diabetic retinopathy

Orbital trauma



Unilateral red eye

^Emergent diagnoses ^^Critical diagnoses



Eye Examination[4]

  • Visual Acuity
  • Pupillary Examination
  • Intra-ocular Pressures
  • Extra-ocular motility and alignment
  • Confrontation Visual Fields
  • External Examination
  • Slit lamp examination
  • Fundoscopic examination

If the patient has risk factors for diabetes or HIV/AIDS, the appropriate diagnostic tests should be considered.

An ophthalmologist will be capable of doing a dilated eye examination, which can aid in the diagnosis and classification of cataract.

Note: If a cataract is suspected to be secondary to trauma, a full neurologic examination and traumatic survey should be done.


  • The diagnosis of cataract is based on the finding of lens opacity on direct ophthalmic examination.
  • Cataracts are typically classified using the lens opacities classification system.
  • Cataracts can be classified as nuclear, cortical, or posterior sub-capsular, however characterization of cataract is typically done by an ophthalmologist.


  • The definitive treatment for a cataract is outpatient surgical management with an ophthalmologist
  • During a cataract surgery, the patient's clouded lens is removed, and it is replaced with a clear, artificial lens for the eye.

Other supportive care modalities that help with visual symptoms include:[5]

  • Using brighter lights while at work or at home
  • A trial of anti-glare suncglasses for outdoor activities
  • Using magnifying lens glasses for reading and other daily


If the diagnosis of cataract is made, the usual disposition is outpatient follow up with an ophthalmologist within 1-2 weeks to discuss the potential for surgical management.

See Also

External Links


  1. National Eye Institute, "Cataracts" <>, accessed 16 Dec 2020
  2. National Eye Institute, "Cataracts" <>, accessed 16 Dec 2020
  3. West SK, and Valmadrid CT, "Epidemiology of risk factors for age-related cataract," Surv Ophthalmol. 1995;39(4):323.
  4. American Academy of Ophtalmology, "The 8-Point Eye Exam" <>, accessed 16 Dec 2020
  5. National Eye Institute, "Cataracts" <>, accessed 16 Dec 2020