Retinal laser is one of the oldest and still one of the most useful treatments in our specialty. It uses a precise beam of light to seal leaking vessels, close abnormal new vessels, or strengthen the retina at risk of tearing. Modern laser is gentler, more targeted and far better tolerated than the lasers of 20 years ago. At Suraj Eye Institute, we use four different laser modalities, each chosen for a specific purpose.

The Four Main Types of Retinal Laser

1. Pan-Retinal Photocoagulation (PRP)

The classical “scatter” laser. Hundreds of small spots are placed across the peripheral retina, sparing the macula and optic disc. By treating the oxygen-starved peripheral retina, PRP reduces the body’s call for new blood vessels, causing them to shrink. Used for:

• Proliferative diabetic retinopathy
• Ischaemic retinal vein occlusions with new vessels
• Other ischaemic retinopathies (sickle cell, Eales’)
• Prevention of neovascular glaucoma

2. Focal / Grid Laser

Small, targeted spots placed near the macula to seal individual leaking microaneurysms (focal) or to cover an area of diffuse leakage in a grid pattern. Used for:

• Non-centre-involved diabetic macular edema
• Macular oedema from BRVO (in selected cases)
• Sealing extrafoveal leak points in CSCR

3. Micropulse / Subthreshold Laser

A modern, gentler laser that delivers the energy in tiny pulses, stimulating the retinal cells without leaving a visible burn. It avoids the scarring of older lasers. Used for:

• Chronic CSCR
• Centre-involving DME (as add-on therapy)
• Macular oedema from BRVO
• Selected cases of dry AMD trials

4. Photodynamic Therapy (PDT)

A two-step treatment: a light-sensitive drug (verteporfin) is given by intravenous drip and accumulates in abnormal vessels; a special low-power laser is then applied to the lesion, activating the drug only where it has settled. The abnormal vessels close while normal retinal vessels are spared. Used for:

• Polypoidal choroidal vasculopathy (PCV) — particularly effective
• Chronic central serous chorioretinopathy (CSCR)
• Some choroidal tumours and selected wet AMD cases

How a Laser Visit Works

• You arrive, have a check of vision and eye pressure, then drops to dilate the pupil.
• You sit at the laser machine, similar to an OCT setup.
• An anaesthetic drop is given. A contact lens may be placed on the cornea with a clear gel.
• The doctor focuses the laser and delivers the spots while you fixate.
• You may see bright flashes and feel a mild dull ache — especially in PRP, sometimes none in focal or micropulse.
• A typical PRP session takes 10–20 minutes; focal laser 5–10 minutes.
• After the laser, your vision will be blurry for a few hours from the dilating drops; arrange someone to bring you home.

What to Expect After Laser

• Vision improves slowly — weeks to months. The goal is usually to preserve, not regain, vision.
• Mild bruising on the white of the eye or eyelid is occasional and harmless.
• Side vision may be slightly reduced after extensive PRP — especially night vision.
• Multiple sessions may be needed, particularly for PRP.
• OCT and OCTA at follow-up visits track treatment response.

Possible Side Effects

• Temporary blurring after the session
• A small ache for a few hours (more common with PRP)
• Reduced night vision or reduced peripheral vision after extensive PRP
• Rarely, a small choroidal effusion or transient pressure rise
• Rarely, scarring close to the macula (avoided with modern focal/micropulse techniques)

How Laser Compares with Injections

For many patients, modern care combines laser and injections in a tailored plan.