Femtolasik- Lens exchange (prelex) - Secundary lens implant - Glasses - Contactlenses

Dr. M. Claeys and Dr. F. De Wilde working for “eyesurgery Belgium” have specialised in refractive surgery, prelex, cataract surgery and oculoplastic surgery for more than 10 years. They offer a variety of ocular surgical procedures in a private setting in Kortrijk
and Gent in Belgium.

The operating theatres are highly professional settings and guarantee sterile procedures in a safe and patient friendly environment.
The overall costs are lower than in the UK due to the high volume of surgery they perform.
About 2500 lasik procedures are performed on a yearly basis in the refractive centre in Drongen ( Belgian Ocular laser centre) which makes it one of the leading refractive centres of Europe.

Dr Claeys and Dr. De Wilde have a lot experience in cataract surgery, performing about 1500 lens implantations a year. In refractive surgery we are able to correct –25 Diopters up to + 15 Diopters with a variety of techniques. The goal of refractive surgery is to reduce your dependence on corrective lenses. In 1989 the excimer laser was first introduced in Europe,
a laser light that can evaporate tissue with an accuray of 0.25 microns.
Using this remarkable technology the cornea is reshaped to conform to your glasses or contact lenses prescription.

Myopia, hyperopia, astigmatism and presbyopia can be treated. Hundreds of thousands of people have eliminated their dependence on corrective lenses with refractive surgery. The eye surgeons working for eyesurgery Belgium use the latest up-to date lasers and have each performed successfully thousands of femtolasik procedures.


With the help of laser rays, the shape of the cornea is permenantly changed, so the light rays are focussed onto the retina.


The Femtolaser is an infrared laser which creates little airbubbles in the cornea by photodisruption to obtain a corneal flap as wanted by the surgeon who introduces all the desired flap characteristics  into the lasermachine. We obtain a corneal flap with perfect even thickness, diameter, side cut, hinge position and width.  

What is LASIK ?

Lasik is the abbreviation for laser in-situ keratomileusis meaning correcting an refractive error by lasertreatment . This treatment combines microsurgery with the most advanced excimerlaser technology. The ultraviolet light source performes an ablation of corneal cells. 
Lasik is the abreviation for laser in-situ keratomileusis meaning correcting an refractive error by lasertreatment . This treatment combines microsurgery with the most advanced excimerlasertechnology

This technique allows a fast and painless treatment resulting in a good sight within the first days after the treatment

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What is the best moment to get a FEMTOLASIK treatment ?
A preliminary eye exam is required, after that the eye surgeon can tell you if LASIK is a suitable treatment for your eyes. A stable visual acuity for more than a year is required. Most eye diseases do not allow for a LASIK to be executed .
People with presbyopia can be helped with LASIK, the eye surgeon applies a comfortvision FEMTOLASIK. One eye is corrected for optimal near sight and the other for optimal sight in the distance, afterwards in the daily life the sight with both eyes will be good near and far.
Another solution for presbyopia is the accommodative or bifocal implant

What needs to be done before I get the treatment ?
After the preliminary basic eye exam and meeting with the eye surgeon, these aspect will be measured and examinated :
* The precise refractive error
* The measurements of the pupils
* The length of the eye
* The corneal thickness and its curvature
* The aberrometrie and topography of the cornea
Watch the video, choose between slow connection or broadband
* The anterior eye chamber
* The endothelliumcell count
* Interior of the eye (lens, retina, blood vessels, optic nerve,...)
After all these exams the eye surgeon  is able to :
1. determine the exact need for correction with the laser
2. exclude any hidden eye disease or problems

Some of these exams require dilatated pupils, the eye drops used for dilatation retain their effect for about 12 hours. The effects are loss of accommodation resulting in a blurry near sight and pupils that are wide open resulting in fotophobia. You will be unable to drive a motor vehicle while the drops have their effect, bring someone along to drive you

What happens the day of the FEMTOLASIK treatment ?
On arrival in the BOLC the nurse will start the preparations. After half an hour  the eye surgeon will start the actual treatment:

Step 1 :Using the femtolaser a small flap-like incision is made in the cornea

Watch the video, slow connection or broadband.

You can see the airbubbles formed into the cornea and also the side cut made with the laser at an angle of 65° to 90° so the flap nicely sticks underneath the flap side cut.

We first create the flap in both eyes and than move to the excimerlaser.

Step 2
: Folding back the flap
Watch the video, slow connection or broadband

Step 3
: Starting lasertreatment : the excimerlaser produces UV-rays, with each laserbeam a small and precise piece (0.25 micron) of the cornea is removed (The laserbeam is an extremely precise tool, its capable of writing words on a human hair). Computer calculations tell the eye surgeon where the laserbeam should be aimed at and for how long.Watch the video, slow connection or broadband

Step 4
: Folding the flap back to its original position
Watch the video, slow connection or broadband

Step 5 : Further fixation of the flap without sutures
Watch the video, slow connection or broadband

After the treatment you will not have any pain. The first hours a sandy or burning feeling is normal. The nurse will provide you with special glasses for during your sleep. You will be unable to drive a motor vehicle for the rest of the day.

What happens after the treatment ?
Rubbing your eyes is strongly forbidden
Protect your eyes from thrusts (sports, during your sleep,...)

The same day of the treatment, begin using the eyedrops according the schedule provided. These consist of lacrimal tears, antibiotics and anti-inflammatory drugs. On each exam after the treatment the eye surgeon will inform you on the continuation of your eye drops.
The day after the treatment most inconveniences are gone and you'll be able to drive a motor vehicle.
Only 2 days absence at work is needed for recovery.

After the first hours, days your sight will improve but may remain unstable for a month.
A small minority (<2%) of patients needs a second FEMTOLASIKtreatment after some months. The flap can easily be re-opened even after several years. 

During the first days after the treatment you may experience dry eyes, eye blur, burning eyes and halo's.

Risk at infection is hugely diminished by the use of the femtolaser and the correct use of the eye drops

Custom Lasik
This is a special laser technique using specific software for myopia only.
Indications are patients with higher order aberrations (after thorough analysis with the aberrometer). The aberrometer makes an account for every aberration in your optic system in the eye (cornea, lens, vitreous body) using wavefront analysis
After this kind of treatment vision at night and contrast viewing is also enhanced.
Patients suffer less from halos and about 50% of the treated patients also gain superior vision, called eagle eyes.

This technique doesn’t require a flap to be cut because laser rays will be directed at the superficial layer of the cornea. After the treatment the surgeon will place protective contact lenses on the eyes that have to remain there for a couple of days.
There is a slower healing process and slower return of vision compared to LASIK. Indications for PRK are a very thin cornea. Both eyes can be treated at the same time.

This is a therapeutic treatment for returning erosions of the cornea.
The laser evaporates a thin layer of the Bowman membrane and so prevents further rupture of the cornea. After treatment a protective contact lens is placed on the eye. Vision returns after a couple of days.

Laser-treatment for myopia, hyperopia and astigmatism.
Only the superficial epithelium layer is placed aside and the laser is directed at the Bowman membrane. After the treatment the endothelium is replaced at its correct position and a protective contact lens is placed on the eye. Vision returns within the first days after treatment.
Indications are possible presumed flap complications or a very thin cornea


A brief surgical procedure during which the patients own eye lens gets replaced by an artificial lens.

Patients over 45 years of age may have reading problems, a condition known as presbyopia.
This loss in lens elasticity is a normal age related change in the eye.
They need reading glasses and now this condition can be treated with prelex (presbyopic lens exchange) also called refractive lens exchange.

Under local anesthetic we aspirate the clear intraocular lens and place a multifocal
or accommodative artificial lens (IOL) in the capsular bag. The artificial lens is placed through a 2.2 mm. self-sealing incision. It is a painless procedure and after the surgery a patch will be placed over the eye and you can leave the center for your hotel. So after this intervention people can again see far and near. They actually have two focal points. The IOL becomes a permanent part of your eye. These procedures are performed in a private setting on an out patient basis. The quality of the multifocal lenses has improved significantly to make prelex surgery highly successful.

Not everybody is suitable for this prelex surgery so the surgeon will do multiple tests to determine suitability. Good candidates are people who struggle with their reading glasses, neurological patients, young patients with unilateral cataract, people with hearing aids and people with allergies to spectacles.

Multifocal implant
In 2002 our surgeons started using these implants. The incoming light is divided into a focus for near and a focus for far distance. After bilateral surgery with this type of implant 81% have no more need for glasses, the others need them for intermediate distance.
These implants can cause in a minority of patients temporary problems such as glare, some loss of contrast and halos around bright lights . Tecnis Multifocal ZM 900 :

Accommodative implant
This implant has a specific design allowing the optic of the lens to click forward when accommodating ( = contraction of the cilliary muscles with increase of vitreal pressure and constriction of the lens capsula causing the lens to click forward ) resulting in a good vision far and near.

For the first month after surgery the eye should be trained, relearning to accommodate (as people do before they are 40 years old when fixating nearby). Some patients still need reading glasses for very small print and reading in dim light.

Human Optics 1CU          LensTec Tetraflex

What happens during surgery ?
PRELEX surgery is done under local anaesthesia. Patients remain awake but will not feel a thing. They will see some vague movements but no details during surgery. The surgeon will make 2 micro incisions and will perform the operation using a microscope.

The name of the technique is faco-emulsification ( faco = lens , emulsification = breaking up using ultrasound waves) The lens is removed with state of the art Infinity technology by Alcon ( market introduced since januari 2005). Alternating ultrasound waves for pulverising the lens and zero frequency waves for diminishing warmth production in the eye makes this technology "a cold emulsification technique". This means it's a very safe procedure that allows for a fast vision recovery.

The front membrane of the lens is opened to provide acces to the lens matter.

During the procedure the lens is broken up and removed using an ultrasound divice.

The new lens or IOL (intra ocular lensimplant) is introduced and centered in the original lensbag keeping the back membrane intact, assuring that the IOL stays in place.
This entire procedure is finished within 20 minutes.
The surgeon will place a plastic shield over the operated eye. This prevents the patient from rubbing the eye involuntary. The patient leaves the hospital the same day after resting for a while.

What is the care afterwards ?
The eye shield should be put on each night, no more need for a bandage, during the first 2 weeks after surgery.

The first month after the surgery patients need to administer eye drops.
Some patients have a hard time using the drops, so a private nurse can come to the house.

The minimal postoperative checkup is the next day, eventually another check up can be done 4 to 6 weeks after the intervention but the local optician-optometrist can also prescribe reading glasses if necessary. Patients with monofocal implants will need reading glasses for all print, patients with accommodative or multifocal implants only need light reading glasses for very small print.

The lensbag (capsule) that remains can cloud in the course of the next months or even years after surgery, to resolve this small inconvenience when symptoms occur (blurred vision) a brief painless laser treatment is performed during normal consultation with the eye doctor.

What are the results after surgery ?
Most patients experience an immediate improvement and more vision restoration requires a couple of weeks patience. We advise patients to take a few days off.
Some very important things to be aware of :

1. No rubbing the operated eye
2. No bending over and lifting heavy things during the first 2 weeks after each surgery
3. No swimming during the first 2 weeks after each surgery

After surgery complications may occur such as infection, bleeding or retinal detachment, but these are very rare.
If you have any complaints after surgery contact the eye surgeon immediately.
It is important to realise that some patients will experience some degree of postoperative glare or halos around lights at night
for the first months. This complaint will in most cases disappear after 3 months.
Should the postoperative result not be satisfactory then a lasik correction can refine the refractive outcome.
Most of the patients report an immediate improvement in their vision and they return to their normal work and lifestyle routines
within a day or two. You may still need a slight correction for computer work or night driving.

In about one third of the cases the posterior capsule that supports the lens becomes cloudy months after surgery. We call this condition “after cataract” and you will be treated with a Yag laser.


• Will I be able to feel the lens ?
The IOL becomes part of your eye, like the natural lens. You will not feel its presence.
• Will the vision result last forever ?
The correction is designed to be permanent, excluding any other eye disease.
• Are there any complications ?
As with any surgical procedure the possibility of complications is always present.
But please remember that most complications are minor and rare (less then 2% of the patients suffer from complications) and can be easily treated with additional eyedrops. These can delay your recovery. The doctor will examine you to determine if you are at higher risk during your initial consultation and discuss this with you.
• How long after surgery before I can see without glasses ?
Your vision will return gradually over a few hours and by the following day your vision will be significantly better.
The improvement continues over the next weeks.
• Will I have 10/10 vision at all distances ?
While these types of IOL are designed to provide 10/10 vision for all distances, some people will not get this grade of success.
Remember, most people do not have 10/10 vision at all distances, even with glasses, contact lenses,… yet function comfortably.
Most patients should not need glasses for 90-95% of their daily activities.
Most people need a simple pair of glasses for reading very small print or for reading in dim light.
• Is there anything I can do to improve my vision even more after having PRELEX ?
Use good light for reading and other near tasks
Don’t use reading glasses for anything but the small print, your natural reading system (accommodation) needs to be used, using glasses too soon makes the system “lazy”


A brief surgical procedure during which an artificial lens is placed in the eye without removing the patients own eye lens.

The artisan implant is used in the refractive surgery to correct higher myopia or to adjust high hyperopia. It's harder to predict the precise outcome of the correction of each refractive error with this method than with the excimerlaser, but the benefit of this technique is that each refactive error can be corrected. The lens is made of PMMA and has a unique patented iris fixation system. Another benefit is that the lens can be removed again.

A very thin foldable lens is placed in front of the natural eye lens resting on the zonula fibres.
No stitches are needed after surgery. Some times laser treatment is needed to correct left over refractive errors. 1 to 3% of treated patients get cataract in the long run.
Indications are high myopia or hyperopia or myopia linked to keratoconus.
Popularity for the ICL is growing fast because people are astonished by their quality of vision,
its reversibility and ease of the intervention.

This is a procedure where we combine an implant lens with a laser to correct eventual residual correction. The indication is a correction over –9 D.,over +3 D. and corrections of astigmatisme.
We can implant an Artisan or ICL lens in the eye. The intervention is performed under local anesthetic. These implantlenses are reversible refractive procedures. The Artisan is positioned in front of the iris while the ICL is placed behind it.
First there is the implantation of the lensimplant in one eye and one or two weeks later the second implant followed 6 weeks later by the laser treatment on both eyes at the same time.


Glasses converge light rays so the image can be focused sharply on the retina.
To correct myopia, you need a negative dioptric value in the glasses.
To correct hyperopia, you need a positive dioptric value in the glasses.
To correct astigmatism, you need a negative cylinder in the glasses.
To correct presbyopia, you need a positive dioptric value in the glasses, these glasses are only used for tasks nearby (reading glasses).
Often it occurs that an optional reading segment is polished in the glasses. You can choose between bifocal or progressive glasses.


Lenses have the same function as glasses and have the benefit that there ar no glasses on the nose. However there are some disadvantages for contact lenses :
• Wearing contact lenses needs a period of time to become accustomed.
• As a user of contact lensen you have to go for a check up more often.
• Cleaning contact lenses has to be done every day.
• Contact lenses can give some irritation when the air around you is dry ( for example in an airoplane or in other “airconditioned” space), dusty or smoky places.
• You become more sensitive to light, there is a greater need for sunglasses.
• An irritated feeling during longtime computer work.
• Less comfort caused by fatigue, bad maintenance or less blinking of the eyes.