The word, ‘cataract’ dates from the Middle Ages and has been derived from the Greek word ‘katarraktes’ which means ‘waterfall’. As of today, cataract refers to the development of opacity in the lens or it’s capsule. There are so many types of cataract, classified based on it’s shape and cause. But the common types include:
- Congenital and developmental cataract
- Capsular cataract
- Subcapsular cataract
- Cortical cataract
- Supranuclear Cataract
- Nuclear cataract
- Polar cataract
CAUSES OF CATARACT
They include:
- Acquired causes e.g diabetes mellitus, drugs like steroids, miotics, etc
- Systemic conditions like Lowe’s syndrome, osteomalacia, dwarfism, etc
- Aging
- Hereditary factor
SYMPTOMS OF CATARACT
- Glare: This basically means an affected person would be extra sensitive to all sources of light,
- Coloured halos: The affected person may complain of seeing rainbow in field of view when exposed to any light source
- Image blur
- Loss of vision
SIGNS OF CATARACT
The optometrist would perform the following tests:
- Visual acuity testing
- Ophthalmoscopy
- Slit lamp examination
Thereafter, grading is done to determine if the cataract is mature or immature.
TREATMENT
Cataracts are usually removed surgically. However non-surgical measures can also be taken, to delay it’s progression and reduce it’s symptoms. Non-surgical measures include:
- Treatment of cause of cataract. e.g for diabetic patients, controlling blood sugar can stop the progression of cataract
- Topical preparations containing iodide salts of calcium and potassium are instilled in it’s early stages to delay progression
- Prescribing of lenses at regular intervals helps improve vision at different stages it’s maturity
- Use of dark goggles in patients with central opacity provides great source of comfort outdoors
- Mydriatics are particularly useful in patients with small axial cataract as its allows light to pass through unhindered through the now enlarged pupil, hence improving vision.