Eye
Lens & vitreous humor
Cataract
Author: Nat Pernick, M.D.
Last author update: 1 February 2014
Last staff update: 22 December 2020
Copyright: 2004-2025, PathologyOutlines.com, Inc.
PubMed Search: Cataract [title] lens pathology review[ptyp]
Table of Contents
Definition / general | Treatment | Gross description | Microscopic (histologic) descriptionCite this page: Pernick N. Cataract. PathologyOutlines.com website. https://www.pathologyoutlines.com/topic/eyelenscataract.html. Accessed January 10th, 2025.
Definition / general
- Defined as progressive opacity of crystalline lens that decreases visual acuity
- Usually develops in older individuals, rarely in infancy or childhood
- Associated with systemic diseases (galactosemia, diabetes mellitus, Wilson disease, atopic dermatitis), corticosteroids, radiation (ultraviolet light or radiation therapy), trauma, glaucoma, uveitis, retinitis pigmentosa, steroids
- Age related cataract is due to opacification of lens nucleus, which becomes brown and distorts perception of blue color
- Changes occur in lens nucleus, cortex and subcapsular regions
- Nuclear changes due to progressive crosslinking and insolubility of crystalline proteins
- Cortical changes begin as small peripheral water clefts and diffuse degenerative changes that coalesce into dense bands of opaque cortical material
- Anterior lens epithelial cells may undergo fibrous metaplasia, creating a thick fibrous plaque between the anterior lens capsule and the anterior epithelial cells
- Congenital cataract:
- Becomes apparent within first 6 months of life
- Posterior subcapsular cataract:
- Migration of lens epithelium posterior to lens equator
- Morgagnian cataract:
- Long standing cataract that undergoes liquefaction of lens cortex with sinking of nucleus into fluid filled sac and clinical brown nucleus
- Soemmering ring cataract:
- Peripheral donut or ring shape due to loss of lens nucleus and much of anterior and posterior cortex
- Also proliferating lens epithelial cells in periphery and equatorial region of lens
Treatment
- Often high frequency sound waves are used to disintegrate the lens (phacoemulsification), then lens contents aspirated and disposed of (not submitted for examination)
- Lens capsule is intact
- Then placement of prosthetic intraocular lens
Gross description
- Senile cataracts are yellow-brown
Microscopic (histologic) description
- Homogenous eosinophilic lens fibers, vacuolization of superficial cortical fibers, extracellular clefts and eosinophilic globules of variable size (morgagnian globules) between lens fibers
