Cataract

• A clear and transparent lens
• Mainly soluble protein and water
• Allows passage of light and forms part of the refractive component of the eye
• Grows throughout life
• Cataract is defined as opacification of the crystalline lens that interferes with vision.

• Aetiological – senile, traumatic, metabolic, toxic, secondary, hereditary.
• Morphological – Nuclear, cortical, Posterior subcapsular.
• According to density – immature, mature, intumescent, hypermature.
• By Location - dislocated, subluxated.

Aetiological Classification

1. Age related - senile (60 years and above)
2. Traumatic
3. Congenital - hereditary, intrauterine infection like rubella, toxoplasmosis
4. Developmental
5. Secondary - drugs (e.g., steroids)

• Age: Incidence of cataract rises exponentially with age after 50 years, most common and definite risk
• High Body mass index
• Gender: Below the age of 50, females have a lower incidence of cataract than men, BUT above that age, they have a higher incidence.
• Disease: Diabetes, Hypertension, renal failure, Myopia, and glaucoma.
• Risk is 13 times more at 70 than at 50. In the Indian population, it has been found to occur earlier - Das et al. found that between 40-60, the prevalence in Indians was 30% and 3% in Caucasians.
• Low socio-economic status
• Rural populations appear to be at higher risk.
• Malnutrition has been implicated, but there are too many co-factors.
• Diarrhea and Dehydration - higher prevalence
• Protective effects of Vit A, C, E - antioxidants.
• Radiation
• Drugs: Corticosteroids, Phenothiazine, Miotics
• Smoking and alcohol
• Female lenses are more sensitive to mechanical stress - calcium has a critical role in fiber stability, and osteoporosis may have a role in a higher incidence.

1. Daylight (ultraviolet light).
2. Diet (riboflavin deficiency).
3. Dehydration (recurrent episodes of dehydration).
4. Drugs (smoking).
5. Diabetes.
6. Dehydration.
7. Demography.
8. Don't know.

Symptom: Poor vision.

Signs:

• Decreased visual acuity.
• Leucocoria.
• Decreased or absent red reflex.
• Visible opacification of the crystalline lens.

Surgery is the only treatment option for cataracts and is essential for restoring vision. Typically, cataract surgery is performed under local anesthesia, except in the case of children. The procedure can be done as a day surgery or may require a few days of admission. Post-operative follow-up is crucial to monitor the healing process.

Surgical Options:

1. Couching: This method is no longer in use, except by traditional healers.
2. Intracapsular Lens Extraction: This involves the removal of the entire crystalline lens along with the anterior chamber intraocular lens (AC-IOL) or the use of glasses for vision correction.
3. Conventional Extracapsular Lens Extraction: In this procedure, the posterior chamber intraocular lens (PC IOL) is used after the removal of the lens.
4. Small Incision Cataract Surgery: This approach uses a small incision and a PC IOL for lens replacement.
5. Phacoemulsification: Phacoemulsification is a modern surgical technique that uses ultrasound to break up the cataract, followed by the insertion of a PC IOL.

Contact lenses can also be used as an alternative to glasses.

• Infection
• Cornea opacity
• Posterior capsular opacification
• Retinal detachment