dr. Djoko Utomo SpM

Biconvex , avascular , colorless , transparent structure

Thick : + 4 mm ; diameter : + 9 mm It is suspended behind the iris by the

zonula, which connects it with the cilliary body

The Lens capsule is semi permeable membrane admit water and electrolytes

The sole fuction : focus light rays upon the retina

The physiologic interplay of the ciliary body, zonule, and lens that result in focusing near object upon the retina is known as accomodation

As the lens age, its accomodation power is gradually reduced

Consist about 65% water ; 35% protein and trace minerals

Pottasium is more concentrated in the lens Ascorbid acis & glutathione are prsent in

both the oxidized and reduced forms

Cataract formation is characterized chemically by :

- reduction in oxigen uptake - lens edema ; calcium & sodium ↑ pottasium, ascorbat acid & protein ↓ damaged lamellar fibers◉ Risk Factors : * Individual : age, sex, ethnic, genetic * Environment : smoking, UV, nutrition, sosioeconomic, education, alcohol, diabetes, dehydration, steroid * Protective : aspirin, hormonal

Cataract-related symptoms are relatively individual and do not correlate absolutely with vision

cloudy or blurred vision reduced contrast increased glare (scattered light) changes in color perception (usually a yellowish

tinge) Double vision (monocular diplopia) complain of more severe symptoms in bright

light (sunshine) or when reading

Acquired cataracts (over 99% of cataracts)◦ Senile cataract (over 90% of cataracts)◦ Traumatic cataract◦ Metabolic Cataract◦ Toxic Cataract◦ Secondary Cataract

Congenital cataracts◦ Hereditary cataracts◦ Cataracts due to early embryonic (transplacental)

damage

Frequently preceded by the presence of radial water clefts in the lens cortex

Morphology :◦ Nuclear cataract◦ Cortical cataract◦ subcapsular cataract◦ anterior or posterior polar cataract

Severity :◦ Incipient cataract◦ Immature cataract◦ Mature cataract◦ Hypermature cataract

Nuclear cataract

Nuclear cataract

Cortical cataract

Subcapsularis posterior cataract

Mature cataract

Hypermature cataract

The most common cause of unilateral cataract in young individuals

Types of injury : Direct penetrating injury Cincussion “vossius” ring Electric shock and lightning Ionizing irradiation

B. Cataract caused by penetrating trauma

C. “vossius” ring after blunt trauma

A

C

B

A. A contusion rosette posterior to the anterior lens capsule has developed after severe blunt trauma to the eyeball

Diabetes mellitus Galactosemia Renal insufficiency Mannosidosis Fabry disease Lowe syndrome Wilson disease Myotonic dystrophy Tetany Skin disorders

Diabetic cataract progresses rapidly

Diabetic cataract appears as bilateral white punctate or snowflake posterior or anterior opacities

Occur with chronic neurodermatitis and less frequently with scleroderma, poikiloderma, and chromic eczema.

Characteristic signs include an anterior crest-shaped thickening of the protruding center of the capsule

Steroid-induced cataract Chlorpromazine-induced cataract Miotic drugs-induced cataract Busulphan-induced cataract Amiodarone-induced cataract

Prolonged topical or systemic therapy with corticosteroids can result in a posterior subcapsular opacity.

The exact dose–response relationship is not known

Chronic anterior uveitis Hereditary fundus dystrophies

◦ Retinitis pigmentosa◦ Leber’s congenital amaurosis◦ Gyrate atrophy◦ Wagner’s and Stickler’s syndrome

High myop Acute congestive angle-closure glaucoma

The most common cause of secondary cataract

The earliest finding is a polychromatic lustre at the posterior pole of the lens

Anterior and posterior subcapsular opacities develop and the lens may become completely opaque

Associated with the subsequent formation of glaucomflecken consisting of small, grey-white, anterior, subcapsular or capsular opacities in the pupillary zone

Indications for cataract surgery◦ Visual improvement◦ Medical indications◦ Cosmetic indications

Surgical techniques◦ Extracapsular cataract extraction (ECCE)◦ Small incision cataract surgery (SICS)◦ Phacoemulsification

Operative complications◦ Rupture of posterior capsule◦ Suprachoroidal haemorrhage

Early postoperative complications◦ Raised intraocular pressure◦ Iris prolapse◦ Striate keratopathy◦ Wound leak◦ Acute bacterial endophtalmitis

Late postoperative complications◦ Suture-related problems◦ Malposition of IOL◦ Corneal decompensation◦ Cystoid macular oedema◦ Opacification of the posterior capsule◦ Retinal detachment◦ Epithelial ingrowth◦ “Sunset” syndrome