P1: OcularDisease2 Quiz2 (Definitions)

Degenerative - SENILE CATARACT

-An age-related, vision-impairing condition characterized by gradual progressive clouding and thickening of the lens of the eye.

-It is the world's leading cause of treatable blindness.

-The most common type of cataract.

NUCLEAR SCLEROTIC CATARACT

-The yellowing and hardening of the central portion of the crystalline lens.

-Also called 'Nuclear Sclerosis'

-Occurs slowly over years

Brunescent cataracts

-are very advanced nuclear cataracts that have become brown and opaque.

Morgagnian or Hypermature Cataract:

-Generalized opacification; The cataract has become very advanced or overripe.

Temporary Second Sight

-why some patients who had previously relied on reading glasses for reading may no longer need them once a nuclear sclerotic cataract starts to form

CORTICAL CATARACT

-Wedge-shaped opacity with clear areas of lens matter

-Mostly present at the periphery

-Occur when the portion of lens fibers surrounding the nucleus become opacified

POSTERIOR SUBCAPSULAR CATARACT (PSC)

-Are granular and plaque-like opacities located in the most posterior cortical layer, directly under the lens capsule

-This type of cataract tends to occur in younger patients than cortical or nuclear sclerotic cataracts

ANTERIOR SUBCAPSULAR CATARACT (ASC)

-Less common than PSCs and it appears the greatest risk factor is trauma to the eye.

-The same as PSC but are located in the front center of the lens.

ANTERIOR POLAR CATARACT

-Small opacity in the anterior capsule of the lens

-generally do not grow during childhood and are typically not visually significant.

-Often managed without surgery.

POSTERIOR POLAR CATARACT (PPC)

-a well demarcated white opacity in the central posterior subcapsular area of the lens.

-Involves complicated surgical removal

MIXED CATARACT

-more than one of the above-described varieties of cataract will occur together in a lens

TRAUMATIC CATARACT

-The clouding of the lens that may occur secondary to blunt or penetrating ocular trauma

-Infrared energy (glass-blower's cataract), electric shock, and ionizing radiation are other rare causes

-Leads to eye lens swelling

Blunt trauma

-classically form stellate- or rosette-shaped posterior axial opacities that may be stable or progressive

-one of two etiologies of traumatic cataract

Penetrating trauma with disruption of the lens capsule

-forms cortical changes that may remain focal if small or may progress rapidly to total cortical opacification.

-one of two etiologies of traumatic cataract

CONGENITAL CATARACT

Painless opacification of the lens that is present at birth or shortly after birth.

DIABETIC SNOWFLAKE CATARACT

Appear as grey-white subcapsular opacities and often progress rapidly turning the entire lens white.

-This rapid onset form of cataract is quite uncommon.