Understanding Various Types of Eye Surgery

Both LASIK and PRK use an excimer laser to reshape the cornea and correct refractive errors — nearsightedness, farsightedness, and astigmatism — but they differ in how the corneal surface is prepared. In LASIK, the surgeon creates a thin hinged flap in the outer cornea using a microkeratome or femtosecond laser, lifts it, applies the laser to the underlying stromal tissue, then replaces the flap. Recovery is rapid — most patients see clearly within 24–48 hours. In PRK, no flap is created; instead the outer epithelial layer is removed entirely, the laser reshapes the exposed cornea, and the epithelium regrows over 3–5 days. Recovery takes longer (1–2 weeks for comfortable vision, 1–3 months for full stabilisation) but there is no flap to displace — which matters for contact-sport athletes, military personnel, and anyone at risk of eye trauma. The key selection criteria: if your cornea is thin or has surface irregularities, PRK is preferred because LASIK requires sufficient corneal tissue to create the flap safely. LASIK is typically favored for patients who need a fast return to work. Both achieve equivalent long-term visual outcomes. The decision is made by your ophthalmologist after corneal topography mapping — not something you can determine from symptoms alone.

Cataract surgery removes the clouded natural lens of the eye and replaces it with a clear artificial intraocular lens (IOL) implanted in the same capsular bag. It is performed under local anaesthetic as a day procedure and typically takes 15–30 minutes. The most common technique is phacoemulsification — an ultrasound probe breaks the cataract into small fragments that are suctioned out through a 2–3mm incision, and the IOL is folded and inserted through the same small opening, avoiding the need for stitches in most cases. The choice of IOL determines whether you will need glasses after surgery. Monofocal IOLs correct vision at one distance (usually distance); most patients still need reading glasses. Toric IOLs also correct astigmatism. Multifocal or extended-depth-of-focus (EDOF) IOLs aim to reduce spectacle dependence for both distance and near, though some patients experience halos or glare at night. In India, surgery is typically done one eye at a time with a few weeks between eyes. Vision stabilises within days to a few weeks. Cataract surgery is one of the highest-volume and highest-success procedures in ophthalmology globally — visual improvement is achieved in over 95% of uncomplicated cases.

Glaucoma surgery does not cure glaucoma — the optic nerve damage already done is permanent. The goal of surgery is to lower intraocular pressure (IOP) to slow or stop further damage and preserve the remaining vision. Several approaches exist depending on glaucoma type and severity. Laser trabeculoplasty (SLT or ALT) uses a laser to improve drainage through the trabecular meshwork; it is often tried before incisional surgery and can lower IOP by 20–30% in suitable patients, with effects lasting several years and repeatable. Trabeculectomy (filtering surgery) creates a new drainage channel under the conjunctiva — a small flap in the sclera allows fluid to escape into a bleb (a blister under the eyelid); IOP reduction is significant but carries risks including infection and hypotony. MIGS (minimally invasive glaucoma surgery) procedures — iStent, Hydrus, XEN gel stent — are newer approaches with lower risk profiles, often performed alongside cataract surgery; they achieve moderate IOP reduction. Cyclophotocoagulation (laser to the ciliary body) reduces aqueous production and is used in advanced or refractory cases. After any glaucoma surgery, ongoing IOP monitoring and often ongoing drops are still required. Surgery is not the end of glaucoma management — it is one tool within lifelong care.

Preparation: stop contact lens use 1–2 weeks before assessment (contact lenses alter corneal shape); arrange transport as you cannot drive post-procedure; disclose all medications (especially blood thinners for procedures requiring injections). On the day: eye drops are used to dilate or numb the eye; most eye surgeries are performed under topical (drop) anaesthetic, occasionally supplemented with a sedative; you are awake but should feel no pain, only pressure. Immediately after: vision may be blurry, the eye may water and feel gritty — do not rub it; protective goggles or a shield are usually worn for the first night. Recovery timeline varies by procedure: LASIK — clear vision within 1–2 days, avoid swimming for 2 weeks; cataract — functional vision within days, avoid strenuous activity and swimming for 4 weeks; PRK — comfortable vision in 1–2 weeks, avoid UV exposure for 3 months; retinal surgery — recovery 2–8 weeks depending on technique, posturing (face-down) may be required. Risks common to all eye surgery: infection (rare, serious — any sudden pain, redness, or vision loss post-op is an emergency), inflammation, raised pressure. Procedure-specific risks: LASIK — flap displacement, dry eyes, halos; cataract — posterior capsule opacification (treatable with YAG laser), IOL dislocation; glaucoma surgery — hypotony, bleb infection. Serious complications are uncommon in experienced surgical hands — your surgeon should quote their personal complication rates.