Senile Cataract Explained: Causes, Symptoms, and Treatment

Senile (age-related) cataract is by far the most common cataract type — over 90% of cases. It develops from cumulative lens-protein damage over decades. Contributing factors: age itself (over 90% of people over 65 have some degree of cataract); UV light exposure (outdoor workers develop cataract 5-10 years earlier than office workers); diabetes (cataract develops 10-15 years earlier); smoking (doubles nuclear cataract risk); prolonged steroid use in any form (inhaled, oral, eye drops — causes posterior subcapsular cataract quickly); high myopia; poor nutrition with low antioxidants (vitamins C, E, lutein); and trauma. Other cataract types include congenital (present at birth, usually genetic or from maternal rubella), traumatic (after eye injury), metabolic (Wilson's disease, galactosemia), radiation-induced, and secondary to intraocular inflammation. Three anatomical types of senile cataract: nuclear (central, causes distance blur and coloured haloes), cortical (spoke-like, causes glare), and posterior subcapsular (behind the lens, causes early reading difficulty and glare disproportionate to distance blur — common in diabetics and steroid users).

Early symptoms often missed: gradual blurring of distance vision that doesn't improve with new glasses; increased glare and discomfort in bright light (car headlights at night especially); colours appear faded, dull, or yellowish; needing brighter light for reading; frequent prescription changes ('second sight' phenomenon — temporary improvement in near vision as cataract develops); double vision in one eye; difficulty driving at night or in bright sunlight; and falls or accidents from poor depth perception. See an ophthalmologist if you have any of these symptoms for more than a month or two, at any baseline for everyone over 40 (then every 2 years), annually if over 60, annually as a diabetic regardless of symptoms, with a family history of cataract or glaucoma, or on any form of steroid. Sudden vision loss is an emergency. Diagnosis is by visual acuity test, slit-lamp examination, and dilated fundus exam — no blood tests needed.

Surgery timing depends on functional impact, not just how the cataract looks on examination. Consider surgery when vision drops below what you need for daily activities (usually below 6/12 or 6/18 in the better eye); reading is difficult even with reading glasses; driving is unsafe due to glare or poor vision; work or safety is affected; you're having falls; or complications are developing (glaucoma from the cataract, inflammation, dislocation risk). The modern approach: no need to 'wait for the cataract to ripen' — that was old thinking when surgery was cruder. Modern phacoemulsification works well at any cataract stage, and earlier surgery means faster, safer recovery with better vision. Government hospitals and NGO-run subsidised programmes make basic cataract surgery accessible at very low cost. Recovery is quick — one-day discharge, return to normal activities in 1-2 weeks, final vision by 4-6 weeks. Both eyes are typically operated 4-6 weeks apart.