The ICL is a thin, soft lens placed inside the eye, behind the iris and in front of your natural lens — like a contact lens that stays in the eye, so you cannot feel it and nobody can see it. Your natural lens is not removed, so your eye keeps its own focusing ability. The EVO+ is STAAR Surgical’s latest model, with a larger optic designed to give better quality of vision in dim light.

The lens

The ICL is made of Collamer®, a soft, UV-absorbing material containing collagen that is highly compatible with the eye. Its central port (the KS-AquaPORT®, just 0.36 mm across) lets the eye’s fluid flow naturally through the lens, which is why a preliminary laser iridotomy is usually not needed. Four footplates rest in a natural groove behind the iris (the ciliary sulcus). The lens comes in four lengths — 12.1, 12.6, 13.2 and 13.7 mm — and is chosen to fit your eye precisely.

What it can correct

• EVO+ ICL: short-sight from −0.5 to −14.0 dioptres.
• EVO+ Toric ICL: short-sight with astigmatism of up to 6.0 dioptres.
• Higher short-sight (up to −18.0 D) can be treated with the standard EVO lens; the overall EVO family is indicated for −0.5 to −20.0 D.

Who is suitable?

• Adults aged 21 or over (the lens is indicated for ages 21–60 in eyes with their natural lens) whose glasses power has been stable for at least a year.
• Enough space in the front of the eye — an anterior chamber depth of at least 2.8 mm — and a healthy cornea with an adequate endothelial cell count.
• Especially suitable for high short-sight, thin or irregular corneas or dry eyes, where laser surgery is unsuitable.

The ICL is not suitable if you have a cataract, glaucoma or raised eye pressure, narrow drainage angles, a corneal disease such as Fuchs’ dystrophy, recurrent eye inflammation, or if you are pregnant or breast-feeding.

Your assessment

Careful measurement is the key to an excellent result. Your work-up includes refraction (with and without dilating drops), corneal topography and tomography, anterior-segment OCT to measure the depth and width of the front of the eye and its angle, specular microscopy of the corneal endothelium, eye pressure, and a dilated retinal examination. The lens power and length are then chosen and ordered for your eye.

The procedure

1. The pupil is dilated and the eye numbed with drops; you are awake but comfortable.
2. A tiny incision of 3.5 mm or less is made at the edge of the cornea, and the eye is filled with a protective gel.
3. The folded ICL is injected and gently unfolds in front of the iris.
4. Each footplate is tucked behind the iris so that the lens rests in front of your natural lens.
5. The gel is washed out; the incision seals itself, usually without stitches. The operation usually takes under half an hour.

After surgery

• Most people see clearly within a day or two. You use drops for a few weeks and avoid rubbing the eye.
• Check-ups monitor the eye pressure and the “vault” — the safe gap between the ICL and your natural lens.
• Your surgeon will advise whether both eyes are treated on the same day or separately.

Risks

ICL surgery is safe and well established, but like all eye surgery it carries risks. These include a rise in eye pressure, inflammation, glare or halos at night, over- or under-correction, rotation of a toric lens, the need to reposition or exchange the lens, gradual loss of corneal endothelial cells (monitored at follow-up), cataract formation and, rarely, infection or retinal detachment. Your surgeon will explain how these apply to you.

In refractive lens exchange your natural lens is replaced with an artificial intraocular lens (IOL) chosen to correct your prescription — exactly the same operation as modern cataract surgery, performed before a cataract develops. Because the natural lens is replaced, you will never develop a cataract in that eye.

RLE is usually best for people over about 45 who have presbyopia (difficulty reading), significant long-sight, or early lens changes — and for whom an ICL is not suitable. With the right IOL it can reduce dependence on glasses for distance, intermediate and near vision.

Lens choices

• Monofocal IOLs — sharp vision at one distance, usually far.
• Toric IOLs — also correct astigmatism.
• Extended depth of focus (EDOF) IOLs — distance and intermediate vision with few halos.
• Multifocal and trifocal IOLs — distance, intermediate and near.

Precise biometry and IOL power calculation is essential. Risks are those of cataract surgery, including later clouding of the lens capsule (easily treated with a YAG laser) and, uncommonly, retinal detachment — which is why RLE is used cautiously in young, highly short-sighted eyes. How to choose the right IOL →

The right choice depends on your measurements, age and lifestyle. A detailed assessment at Suraj Eye Institute will tell you which options suit your eyes.

Or call 0712-2595600 / 0712-2595636

1. STAAR Surgical. Visian® Implantable Collamer® Lens (EVO|EVO+ ICL) — Directions for Use, eDFU-0009 Rev 03. edfu.staar.com

EVO+, Visian, Collamer and KS-AquaPORT are trademarks of STAAR Surgical. Indications and available powers vary by country and lens model. Animations and diagrams are schematic illustrations created by Suraj Eye Institute for patient education and are not to scale. This page is general information and does not replace a consultation.