The Ultimate Guide To Refractive Lens Exchange – Everything About RLE

Lens replacement surgery, such as refractive lens exchange (RLE), is growing in popularity. Lens exchange procedures have a low level of risk, permanent results, a positive financial outcome when compared to traditional vision correction and speedy recovery times.

If you are deliberating whether lens replacement or laser eye surgery is the correct choice for you, then you have come to the right place. Focus Clinic offers a free initial consultation for anyone considering their surgical options to correct refractive issues.

Before you see one of our specialist ophthalmologists, you may want to familiarise yourself with our complete lens replacement surgery guide.

A Short History of Lens Implants

Using artificial implantable lenses (intraocular lenses, IOLs) to correct refraction issues is now a standard procedure performed the world over. But how did we get to this point?

During WWII, RAF pilots would routinely suffer wounds in combat. Often these injuries would involve shards from the plastic components of the aeroplane canopy becoming embedded in the pilot’s eyes. One of the on-hand eye surgeons, Sir Harold Ridley, would treat the pilots and continue to administer care even after the war.

History Of Lens Implants

It was during this time that Dr Ridley noted Perspex that remained in the eye caused no inflammatory effect. It was not rejected by the body, as other materials would be. These observations would catalyze the creation of the implantable lens, with the first lens replacement surgery taking place in November of 1949.

Ridley faced backlash from the medical community. However, he continued to persevere and refine his technique, and by 1981, intraocular lenses were granted approval by the Food and Drug Administration (FDA) as being ‘safe and effective’.

What is Lens Replacement Eye Surgery

Lens replacement surgery is a standard outpatient procedure used to correct refractive errors within the eye. The treatment will replace the clear natural lens that is found towards the front of the eye with an artificial implant.

Refractive lens exchange (RLE), as the procedure is commonly referred to, is also used in patients showing early signs of cataracts. If the cataract is affecting vision, the same operation is then called cataract surgery.

Sometimes the eyes natural lens will not be removed. Instead, a corrective implant will be placed either behind or, much less commonly, in front of the iris. These artificial lenses are known as PIOLs (phakic intraocular implants) or Implantable Contact Lenses (ICL).

ICLs are usually reserved as an alternative for patients unsuited to receive laser refractive treatment. Several different lens types have been developed to deal with the various refraction errors that occur.

Here you will find information about different types of lens replacement surgery that are available:

Refractive Lens Exchange (RLE) Surgery Types

RLE is a procedure in which the eyes natural lens is removed and replaced with an artificial intraocular lens (IOL). An increasingly popular treatment for refractive issues, RLE is one of the most common refractive procedures performed in the UK.

IOLs come in two main types:


Monofocal IOLs are designed to improve standard refractive errors such as short-sight or long-sight. The implants are usually selected to correct the patient’s distance vision. This approach provides a clear sight for driving or television. As the natural close focusing ability of the lens has been removed, the patient will need to use reading glasses for near focus.


Multifocal IOLS (MIOLs) provide a greater depth of focus when correcting refractive errors. The most common implants used today are trifocal lenses. These MIOLs improve vision for far, intermediate (PC range) and close vision (reading), reducing the need for corrective glasses or contact lenses post-surgery.

Monofocal IOLs can be used to produce ‘monovision’, an approach commonly used with contact lenses. One eye is corrected so that distance sight from that eye is clear. The implant will be chosen to correct any pre-existing refractive error. The lens implant in the other eye is selected to leave a myopic (short-sighted) focus. Reading vision will be clear in this eye without the need for glasses, although distance objects will be somewhat blurry.

While having a different focus in each eye sounds strange, the brain readily adapts. The brain ‘blends’ the images from each eye to provide an effective solution for clear far and near vision

IOL monovision is often used to correct presbyopia (age-related long-sightedness). Typically, monofocal lenses with monovision will require surgery on both eyes.

Some patients may already be doing this successfully with contact lenses. If so, then IOL monovision will likely be a success. For those who have never experienced monovision, a trial with contact lenses can sometimes be helpful.

How Is Lens Replacement Surgery Performed

RLE will be performed with local anaesthetic applied in drop form to the eye. Overall the procedure takes around 15 to 20 minutes per eye.

The most common plan is to operate on one eye at a time. The second eye procedure often takes place one week following the first. There may be a reason for your surgeon to elect to operate on both eyes on the same day, but this is an exception.

RLE is done as an outpatient procedure, meaning you will have surgery and return home the same day to recover. Overnight stays are not required for refractive correction surgeries.

During the procedure, five main steps will be followed once the anaesthetic has numbed the eye:

  • Creation of entry point – Small self-sealing entry points will be created in the front of the eye, where the cornea meets the white of the eye.
  • Capsulotomy – A thin circular disk is removed from the membrane shielding the anterior (front) surface of the natural lens.
  • Phacoemulsification – In this step, the eyes natural lens is liquefied and removed from within the lens capsule, achieved with a high-frequency ultrasound vibrating probe and vacuum.
  • IOL implantation – Once the eyes natural lens has been completely removed, the IOL is placed into the eye. The implant is flexible and can be rolled up and injected using a special insertion tool. It can be passed through the same incision through which the original lens was removed during phacoemulsification. The IOL is inserted into the ‘capsular bag’ in a folded state, and your surgeon will watch as the IOL unfolds and will set it into the desired position.
    A gel will be applied during this step to support the front portion of the eye.
  • Wash – When the IOL has been placed in position, the supporting gel is washed from the eye, and antibiotic fluids are applied to prevent infection.

Femtosecond lasers are being evaluated during RLE surgery, with some clinics opting to use them during several of these steps. The level of success post-surgery is currently identical between conventional phacoemulsification surgery and femtosecond laser-assisted procedures. Safety levels for the patient are also similar, although some studies showing greater safety with a conventional phaco approach.

Cataract Surgery

Cataract surgery follows the same process as refractive lens exchange. The key difference is that the lens removed during cataract surgery has begun to become cloudy and opacified as opposed to the clear state of the natural lens.

Patients suffering from cataracts will display some or all of these symptoms:

  • Blurred and dim vision
  • Glare from night sources, particularly at night
  • Haloes surrounding light sources
  • Vision becoming ‘yellower’ overtime
  • Poor vision at night
  • Double vision within one eye
  • Sensitivity to light

If you believe you may be affected by cataracts, you should schedule an appointment with your eye specialist for an examination and discuss next steps regarding treatment options.

Implantable Collamer Lens (ICL) Treatment (Phakic Intraocular Lens, PIOL)

An ICL, sometimes referred to as Implantable Contact Lens, is an alternative for patients who have no sign of cataract development. The ICL is implanted within the eye without first removing the natural crystalline lens. These implants are referred to as phakic intraocular lenses (PIOLs). PIOLs can sit either behind the pupil or, less commonly, in front of the pupil.

PIOLS can be thought of as a permanent contact lens housed within the eye.

ICLs are a favourable treatment for people with high levels of prescription, often a solution for younger patients who have been found unsuitable for laser surgical options.

Within the UK, the most common PIOL used is the Visian ICL (Implantable Collamer Lens). These are soft, malleable IOLS that sit in front of the eye’s natural lens, but behind the pupil.

After the surgery, you will not be able to see or feel the implant, and it requires no cleaning.

If you are suitable for ICL, your ophthalmologist will open discussion with you regarding treatment options.

Lens Replacement Surgery Alternatives

Lens replacement surgery is generally reserved for those who are not suited to laser refractive options such as LASIK or PRK. Patients are often aged 50+ with lens dysfunction or early lens opacities. However, if you have reached us to find information regarding the available non-lens options, here is a short recap on laser eye surgery procedures:

  • LASIK Treatment – During LASIK, a small corneal flap is created using a femtosecond laser exposing the collagen material underneath. Once this flap is created, the cornea beneath is reshaped using an excimer laser to improve the ability of the eye to focus images onto the retina.
  • LASEK / PRK – Similar to a LASIK procedure, LASEK (also known as PRK) uses an excimer laser to reshape the corneal tissue, improving the eye’s ability to focus. In the initial step, a thin epithelial skin cell layer is removed and discarded. In LASIK, a flap is created without removal of surface cells.
    This skin debridement in PRK can lead to a slightly longer initial healing period, as this layer of cells will require time to regenerate.
  • SMILE – SMILE is a newer procedure when compared to LASIK and LASEK; a femtosecond laser is used to create a small lenticule within the cornea. Then through a small incision, this lenticule is removed, resulting in the cornea being flattened to improve focusing.
    SMILE, however, did not perform as well as LASIK procedures in modern FDA studies. Small re-treatments needed after the initial surgery cannot be performed with SMILE. Enhancements are usually carried out with LASIK or PRK, as these are capable of precise smaller corrections. More advanced technology is being developed to improve the process. Improvements will include adding eye tracking, which has been available during LASIK for 20 years.

Who is Suitable for Lens Replacement Eye Surgery?

For patients over 50 who have been found unsuitable for laser eye surgery, due to a higher prescription, are likely candidates for lens replacement. Most levels of myopia (short-sightedness) and hyperopia (long-sightedness) can be treated with refractive lens exchange surgery.

IOLs explicitly made to treat astigmatism (toric lenses) are also available. It is possible to combine lens implantation with laser eye techniques to expand on the range of astigmatism treatment available. Or fine-tune the level of correction post-surgery.

RLE is also the primary treatment for patients experiencing cataracts, as the clouded cataract-affected lens needs to be removed to achieve clear vision.

Younger patients who are unsuited to laser correction techniques may be offered PIOL (ICL) as a corrective option for their refractive issues. Usually, this is because of extreme prescriptions, pre-existing eye surface or corneal abnormalities.

Suitable PIOL candidates will be 18 years or above and have a stable prescription for at least 12 months prior, with no change above 0.5D in that time.

A range of prescriptions can be treated with PIOL implants:

  • Myopic (short-sighted) errors up to -17.00D
  • Hyperopic errors (long-sight) up to +10.00D
  • Astigmatism up to +/- 4.50D

The range of prescriptions that can be corrected through PIOL procedures may be extended with supplemental laser refractive surgery such as LASIK or PRK.

Why may I not be suitable for lens replacement surgery?

Prior to any decisions being made regarding the type of procedure that will be suitable for you, your ophthalmologist will take you through a thorough consultation and screening process. This is a critical step to take to ensure the maximum level of success for any surgery to correct focusing errors.

There are several contraindications against and indicators for lens replacement surgery. These can include:

Refractive lens exchange in myopic short-sighted eyes:

  • In eyes with high axial myopia, depth and stability of the anterior chamber are abnormal, which necessitates the use of dispersive (heavy) viscoelastic material.
  • In eyes with excessive axial length, the risk of perforation during retrobulbar injections is high.

For myopic eyes, consider avoiding treatment in cases with:

  • Eyes with advanced peripheral lattice degenerations
  • Young eyes with no posterior vitreous detachment (PVD)
  • Lacquer cracks in high myopia or myopic choroidal new vessel growth in the other eye
  • Presbyopic eyes with macular degeneration beginning in the fellow eye

Refractive lens exchange in hyperopia

Small, hyperopic eyes with shallow depth to the anterior chambers are more predisposed to closed-angle glaucoma. Shallow chambers make even moderate hyperopia an indication for RLE, offering an excellent benefit/risk ratio.

In elderly patients where accommodation is reduced despite having a clear lens, its removal with multifocal IOL implantation can be a good option in the absence of other ocular pathologies.

In several studies, satisfactory refractive results were stated in the RLE treatment of long-sightedness. Complications such as retinal detachment or cystoid macular oedema (CME, CMO) are lower than in RLE for the treatment of short-sight.

That is not to say that this is an exhaustive list as the eye is a complex organ. Other factors that come into play which will be assessed during consultation. Existing conditions that are well-monitored and controlled may not affect your viability to receive lens replacement surgery.

Should I Have Lens Replacement Surgery? Is It Worth It?

Contemplating eye surgery in any form can be daunting for anyone. Worries about risks, financial implications and if the level of success is worth it.

Thorough consultations are in place to ensure the suitability of patients and select the right treatment for the individual, providing a fantastic level of success. The procedure itself is painless and lasts no longer than 15-20 minutes per eye, with recovery time lasting days to weeks.

Although some patients may feel nervous about the significant upfront investment, many finance options are now available to split the cost over a timescale to suit. When weighed against the cost of your current corrective measures (eyeglasses, contact lenses), lens replacement surgery is estimated to cost less when calculated over an individual’s lifetime.

Lens Replacement Surgery Cost

The cost of lens replacement surgery will vary from clinic to clinic. Prices range from £5,000 up to £10,000 for both eyes, depending on the surgeon’s skill and experience, the technology used and the quality of the eye clinic you choose.

At Focus Clinic, prices for refractive lens exchange start at £6,500 for complete treatment to both eyes. Implantable Collamer Lens procedures are priced at £7,500 for comprehensive treatment to both eyes.

We offer a range of finance options both with and without interest, at prices to suit all budgets.

Benefits of Lens Replacement Eye Surgery

When premium modern multifocal IOL’s are used, four out of five patients no longer require the use of other corrective measures (eyeglasses, contact lenses). Those that do still require some form of correction post-surgery only do so for specific activities, such as reading or driving.

Less dependency on eyeglasses and contact lenses allows patients the freedom to live a more active lifestyle. It results in improved levels of health and the side-benefits that brings.

Freedom From Cataracts After RLE

If you had RLE surgery (refractive lens exchange), you won’t require cataract surgery later in life. The eyes natural lens that can become clouded has been removed and replaced.

Excluding those rare instances where surgical or healing complications arise, patients are almost always entirely satisfied with the level of success from RLE. A large number describes the procedure as life-changing for them.

Providing that no other, unrelated, eye issues develop (glaucoma, macular degeneration) patients can expect to live a full life with improved vision post-surgery.

Recovery From Refractive Lens Exchange Treatment

Eye lens replacement surgery is a straight forward outpatient procedure, meaning you will be in and out of the clinic within the same day. Many patients report enhanced vision during the first 48 hours, will the full scope for recovery averaging around six weeks.

Post-surgery your eyes will likely appear red and bruised; this is to be expected and will fade after a few days. It is always advisable to have a friend or family member drop you off and pick you up from the clinic, avoiding public transport.

Surgery Day

Clear vision can present just a couple of hours post-surgery, but it is worth noting that all patients are different, and healing timescales vary from person to person. You may even find that your vision has become distorted or wavy.

Your eyes are just adjusting to the optical properties of the new IOL that has replaced the optics of the previous natural lens. You may feel anxious about these symptoms, but it is essential to understand these are entirely normal experiences after lens replacement.

First Week

During the first week, it is common for lights to appear brighter than before; your eyes may still exhibit a sense of grittiness. Bruising and redness should have started to clear by now if it had not already.

Your vision should be much sharper, and between three and seven days after surgery, all normal activities can be resumed, excluding swimming. If you have met the DVLA standard, you may also be permitted to begin driving again too.

First Month

Your eyes should have mostly recovered by the two-week point. It is around this time you may get measured for new eyeglasses, dependant on how well the healing process has gone.

Some people are surprised to find out that they may still require eyeglasses following lens surgery. But if monofocal implants have been used, you will need to continue using eyeglasses for near-sight activities such as reading or computer usage. If multifocal lenses have been used, glasses may not be required as these lenses restore vision over multiple distances.

By four weeks, you will have finished any prescribed eyedrops, and feelings of grittiness within the eye should have disappeared, along with bruising and redness.

Risks And Side Effects Of Lens Replacement Surgery

Lens replacement surgery can reduce the need for any other corrective measures and improve vision. However, as with any surgical procedure, there are several risks you should know.

All these risks are minimal. However, your ophthalmologist will discuss them in detail with you during your consultation, and answer any questions you may have regarding post-surgery complications.

Vision After Surgery Is Not As Expected.

Following surgery, there may still be some remaining short- or long-sightedness, or astigmatism. Eyeglasses may still be needed to perform daily tasks such as driving or reading.

This may depend on the type of lens used during the procedure. Treatment may be readily available with LASIK or PRK if the prescription does not settle by two months after the lens procedure.

Glare & Haloes

Patients may notice glaring, sometimes described as a ‘starburst’ or haloes surrounding light-sources, especially noticeable during the night. These effects will continue to diminish several months post-surgery with most patients reporting no effect after three months.

Red, Sore or Irritable Eyes

It is normal to experience a reddening of the eye following surgery. This redness will disappear over weeks and has no bearing on vision.

Some patients also report irritated eyes or a feeling of ‘grittiness’ in the eye. These symptoms can be treated with eye drops formulated for dry eye.

Posterior Capsule Opacification

Posterior capsule opacification (PCO), sometimes known as a secondary cataract, can develop following lens replacement surgery. Similar to a cataract, the patient’s vision will become cloudy. This can happen any time from a couple of weeks to a few years following surgery.

When a patient develops PCO, they may need to have a straight-forward out-patient laser treatment; this is known as a YAG laser capsulotomy or posterior capsulotomy. This laser option is designed to clear away any whitening of the capsule.

YAG laser surgery can result in an increased number of floaters within a patient’s vision but will settle down over time, with no remarkable long-term effects.

Rare But Possible Lens Surgery Complications


Despite the use of antibiotic eye drops, a severe eye infection can occur in less than 0.05% of patients following surgery. This is an infrequent occurrence, but it is vital that any pain or unexpected loss of vision is reported to your eye specialist immediately.

Despite the use of antibiotic eye drops, severe infection can occur in less than 0.05% of patients following surgery. This is an infrequent occurrence, but it is vital that any pain or unexpected loss of vision is reported to your eye specialist immediately.

Retinal Detachment

Retinal detachment is a serious, sight-threatening event. If the retina becomes detached from the underlying tissue supporting it, then it cannot function correctly.

Reattachment is time-sensitive; if the attachment of the retina is delayed, permanent loss of vision can ensue.

If you experience any flashing lights within your vision, a sudden increase in floaters or a curtain effect affecting your sight, you may have a detached retina. It is crucial that once you have recognised these symptoms and suspect a detached retina, you contact your eye specialist immediately.

Fortuitously, repairs can be made surgically. Your ophthalmologist will be able to assess the retina and decide on the best course of action going forward.

Cystoid Macular Oedema

CMO (cystoid macular oedema; CME in the United States) affects the macula, the area of the retina that delivers clear central vision. CMO/CME occurs when cyst-like pockets of fluid form in the macula, causing the retina to swell.

CME/CMO is painless but can result in a diminished level of central vision, with peripheral vision remaining unaffected. If the CME presented is mild it can often-times resolve itself naturally, but more severe cases will be treated with eye drops.

Reducing The Risks

The best way to reduce the risk of complications following any eye procedure is to follow the aftercare advice provided by your eye doctor. Correct use and application of any eye drops and medication you have been prescribed will ensure the maximum chance of success.

Being aware of any complications and their symptoms that may develop post-surgery will also prove invaluable. If you do notice increasing pain, photosensitivity, flashes of light or a sudden increase of floaters you should report to your eye specialist or eye casualty.

Choosing The Right Clinic

Ultimately the principal factor when considering how successful lens replacement surgery may be for you, is your eye health before the procedure. However, this will be something that remains out of your control.

What does remain under your control is choosing the right eye clinic to perform your refractive surgery.

At Focus Clinic, our work and levels of customer satisfaction speak for itself. You can view our eye lens replacement clinic reviews. Currently ranked as the #1 clinic on Trustpilot, our in-house surgeons have a combined 45 years’ experience, having performed over 35,000 procedures between them.

If you are considering lens replacement surgery, Focus Clinic London offers a free initial consultation with no obligation to discuss your options.

Focus Clinic delivers world-class levels of customer care and satisfaction, evidenced by our lens replacement surgery reviews. Choosing a reputable clinic with an extensive breadth of experience is the first step in ensuring the highest level of success.


Ultimately the principal factor when considering how successful lens replacement surgery may be for you, is your eye health before the procedure. However, this will be something that remains out of your control.

What does remain under your control is choosing the right eye clinic to perform your refractive surgery.

At Focus Clinic, our work and levels of customer satisfaction speak for itself. You can view our eye lens replacement clinic reviews. Currently ranked as the #1 clinic on Trustpilot, our in-house surgeons have a combined 45 years’ experience, having performed over 35,000 procedures between them.

If you are considering lens replacement surgery, Focus Clinic London offers a free initial consultation with no obligation to discuss your options.

Focus Clinic delivers world-class levels of customer care and satisfaction, evidenced by our lens replacement surgery reviews. Choosing a reputable clinic with an extensive breadth of experience is the first step in ensuring the highest level of success.

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100% 20/20 vision

Focus Clinic has a remarkable 100% success rate for 20/20 vision. We know of no other clinic that has matched these results. There is a big difference between, for example, 98% and 100% success, especially if you are in the 2%.

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Your 10 Year Guarantee means you can return at any time if you have additional questions on the quality of your vision. If you have distance vision correction for short-sight then any repeat laser eye treatments to correct a return of myopia in the first 10 years are included free of charge.*

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We have the highest trust rating of any ‘eye treatment’ rated clinic, according to independent review site TrustPilot. With an outstanding 9.9 out of 10, when it comes to your eyes, choose the clinic that actual patients trust the most.

*Terms and conditions apply, excludes any age-related changes and conditions unrelated to the primary treatment

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