Who is Laser Eye Surgery for?

You are probably a good candidate for Laser Eye Surgery if you:

• Are aged 18-50; beyond the age of 50 other vision correction surgery options may be more suitable.
• Have had a stable focusing error for at least a year.
• Have a focusing error within the range of +3 dioptres to -8 dioptres.
• Have otherwise healthy eyes.
• Enjoy good general health.

You are probably NOT a good candidate for Laser Eye Surgery if:

• You are especially risk averse. No surgical results can ever be 100% guaranteed, and certain complications are unavoidable in a small percentage of patients.
• It will jeopardise your career; some jobs prohibit certain vision correction procedures. Be sure to check with your employer/professional society/military service before undergoing any procedure.
• Cost is a significant issue.
• You have an autoimmune disease like lupus or rheumatoid arthritis, or are on medications like retinoic acid or steroids.
• Have a severe focusing error – other vision correction surgery options may be more suitable.
• You have herpes virus eye infections, keratoconus, cataracts or glaucoma.

Laser Eye Surgery Preparation

Your decision to have Laser Eye Surgery should be a positive and informed decision based on an accurate assessment of the potential risks and benefits specific to your case.

You should fully inform yourself as to the clinical reasons behind your treatment, the predictability of the procedure’s results and the timescales involved.

Once you have decided which centre to go to, the first part of Laser Eye Surgery preparation is to arrange a consultation, which should always be with the surgeon who will be carrying out your treatment. Double check this, as some high street clinics don’t always provide this.

The surgeon should always be an expert ophthalmic surgeon trained in the practice of Laser Eye Surgery and the diagnosis of corneal disorders, and they should always carry out a comprehensive eye examination.

This examination should include:

1. Refraction – A check on the focus of the eye.

2. Scanning Slit Corneal Topography – A map of the corneal shape and power.

3. Corneal Pachymetry – A measurement of corneal thickness.

4. Pupillometry – A measurement of the size of your pupil in the dark.

5. Keratometry – A measurement of corneal power; this information is extremely useful should you need surgery to remove cataracts in the future.

6. Dilated examinations of the retina i.e. after drops are instilled to dilate the pupil.

7. Wavefront Scan: This is a measurement of the focussing error of the eye which is much more sensitive and personalised. When the treatment is carried out using these measurements it is called wavefront based Laser Eye Surgery. A standard Laser Eye Surgery treatment is one which uses the spectacle prescription. The visual results are generally better with wavefront based treatments, provided the wavefront measurements used meet a set of quality criteria. If the wavefront measurement is of poor quality, better results are obtained using the glasses prescription.

Using contact lenses can produce inaccurate corneal measurements. It is critical to have a contact lens-free period prior to attending your consultation. This period is ideally a week for soft contact lens and four weeks for rigid gas-permeable lens users.

Laser Eye Surgery Techniques

Ever since the first Laser Eye Surgery techniques were used in 1989, millions of patients around the world have had successful Laser Vision Correction. Modern day results are much more predictable and much safer compared to the procedures 20 years ago, due to improvements in laser technology and a better understanding of the optics and the healing processes of the eye.

How Laser Eye Surgery Works

The laser used in Laser Eye Surgery to alter the focus of the eye is called the excimer laser. This emits ultraviolet light which is absorbed by the surface of the cornea, allowing very precise sculpting of corneal tissue.

This ability to sculpt microscopic amounts of corneal tissue approximately 0.25 microns (1/4000 of a millimetre) in thickness with every laser pulse gives the surgeon exceptional control in changing corneal curvature and hence its focus.

Laser Eye Surgery Techniques

There are three Laser Eye Surgery techniques: photo-refractive keratectomy (PRK), Laser Intrastromal Keratomileusis (LASIK), and Laser Epithelial Keratomileusis (LASEK). The effects are similar, but because the laser sculpts at different corneal depths, the healing responses differ. The risks and benefits differ for each technique, and many of the problems associated with Laser Eye Surgery are due to the wrong technique being chosen for a particular eye.

PRK is now an outdated technique, and the current state-of-the-art techniques are LASEK and LASIK. LASIK Laser Eye Surgery is the most commonly used procedure, and involves creating a flap on the cornea under which laser sculpting occurs. These flaps can be created using a mechanical blade or a more accurate and more predictable femtosecond laser.

The femtosecond laser technique is the only one of these two which we practice here at the Vision Surgery & Research Centre. The surgeon uses two separate lasers: the femtosecond laser to create the flap and the excimer laser to sculpt the cornea and adjust focus.

This all-laser LASIK technique is also known as blade-free LASIK, zLASIK, Intralase or iLASIK. Blade-free LASIK improves the safety of LASIK and is the current state-of-the-art in Laser Eye Surgery.

This centre no longer performs either bladed LASIK or PRK. The two techniques used at this centre are blade-free LASIK using the Zeimer femtosecond laser, and LASEK. Furthermore, all procedures are wavefront-based procedures.

Blade-free wavefront LASIK is the preferred Laser Eye Surgery technique. However certain types of eyes are unsuitable for LASIK, and in these patients wavefront LASEK is preferred. The choice of technique is absolutely critical and is based on individual lifestyle, visual needs, pre-surgery ocular measurements and pre-existing ocular conditions. This is a completely bespoke approach to LASER vision correction, with all patients being offered the best possible treatment for their particular set of eyes.

LASIK Laser Eye Surgery Process

Blade-Free (Femtosecond) Wavefront LASIK

The blade-free wavefront LASIK Laser Eye Surgery process is the most advanced technique, with improved visual results and reduced risk of flap complications.

Patients are almost pain-free after treatment and there is usually an immediate improvement in their vision.

Patients with very thin corneas are not ideal candidates for any type of LASIK Laser Eye Surgery, and wavefront LASEK is the preferred choice in such cases.

During Surgery

LASIK Laser Eye Surgery is completely painless, and it usually takes about ten minutes per eye. On arrival at the hospital a nurse will assess you. This is followed by a wavefront scan and a final discussion of the best treatment option.

This is also your opportunity to ask us any questions you may have prior to you giving your formal consent to the procedure by signing the consent form. You will then be escorted to the operating theatre, where you will lie down on a reclining chair and anaesthetic drops will be placed in your eyes. A clip is used to stop your eyelids from blinking.

The femtosecond laser hand-piece is then gently placed on the eye, and a vacuum is allowed to build so that the eye remains still. Your sight may blur and you may experience mild pressure but there is no pain at all. The femtosecond laser is then focused and scanned to create the LASIK flap. The femtosecond laser hand-piece is removed and the corneal flap is gently lifted and turned on its side. You will be asked to concentrate on a flashing target light (fixation light) within the laser, and the laser sculpting commences. A series of clicking or clapping noises are heard as the excimer laser painlessly removes corneal tissue to a pattern pre-determined by your wavefront prescription.

Patients may be aware of a gentle tapping sensation and a faint smell similar to singed hair. However this is not an issue, as the laser is not a thermal laser and no tissue is being heated or burned during the process. The laser component of the treatment usually takes a few seconds and varies with your prescription. Once LASER sculpting is completed, the flap is repositioned and its alignment checked. It takes a couple of minutes for the flap to stick to the cornea. A protective eye shield is applied after applying antibiotic drops.

After Surgery

It is common for the eye to be red, watery, feel scratchy and be very light sensitive for 4-6 hours following treatment. There is mild (if any) discomfort for the first 24 hours after treatment. Recovery of vision to a reasonable level is almost immediate, and typically most patients notice a significant improvement in their vision the next day.

You should wait at least one week following LASIK Laser Eye Surgery before beginning any non-contact sports. To help prevent infection, you will need to wait for up to 4 weeks after surgery before using lotions, creams, or make-up around the eye. You should also avoid swimming and using hot tubs or whirlpools for a month. Strenuous contact sports such as boxing, football, karate, etc. should not be attempted for at least 4 weeks after surgery. It is important to protect your eyes from anything that might get in them and from being hit or bumped. It is essential to protect your eyes from bright sunlight by using a good pair of sunglasses for at least 3 months after surgery.

During the first few months after LASIK Laser Eye Surgery, your vision may fluctuate. It may take up to 3 to 6 months for your vision to stabilise after treatment. Most LASIK patients have a mild to moderate degree of dry-eye up to 6 months after treatment and can require artificial tears or rarely punctal occlusion during this period. Glare, haloes, difficulty driving at night, and other visual symptoms may also persist during this stabilisation period.

Your follow up check-ups for 6 months are included in the price of surgery. It is advisable to continue with annual eye health check-ups after that.

LASEK Laser Eye Surgery Process

Wavefront LASEK Process

This is a very successful Laser Eye Surgery technique, with a superlative safety record and good visual results in patients with low levels of focussing errors.

The drawbacks are in the immediate postoperative period, which can be painful and can involve a slower visual recovery and corneal scarring or haze, especially in patients requiring correction for high levels of short-sightedness.

During Surgery

The LASEK Laser Eye Surgery Process is completely painless, and it usually takes about fifteen minutes per eye.

On arrival at the hospital a nurse will assess you. This is followed by a wavefront scan and a final discussion of the best treatment option.

This is also your opportunity to ask us any questions you may have prior to you giving your formal consent to the procedure by signing the consent form. You will then be escorted to the operating theatre, where you will lie down on a reclining chair and anaesthetic drops will be placed in your eyes. A clip is used to stop your eyelids from blinking.

The surface corneal epithelium is loosened from its underlying attachments by chemical means. The epithelium is then gently rolled back to form a flap with a hinge under the top eyelid. The patient then concentrates on a target light (fixation light) within the laser, and the laser sculpting commences. A series of clicking or clapping noises are heard as the excimer laser painlessly removes corneal tissue to a pattern pre-determined by the patient’s own refraction. Patients may be aware of a gentle tapping sensation and a faint smell similar to singed hair. However this is not an issue, as the laser is not a thermal laser and no tissue is being heated and burned during the process. The actual laser component of the LASEK treatment usually takes a few seconds. Antibiotic drops are applied and a bandage contact lens put into the eye at the end of the procedure.

After Surgery

It is common for the eye to be red, watery, feel scratchy and be very light-sensitive for 24 to 48 hours following LASEK Laser Eye Surgery. There is moderate discomfort to severe pain for the first 24 to 48 hours after surgery. After 3 to 4 days, the bandage contact lens is removed. Recovery of vision to a reasonable level typically takes 3 – 6 days, while stability of vision is achieved usually by 2 weeks, although in rare cases it could be 3 – 6 months. Most people are able to return to work after 3 – 6 days. Antibiotic drops are prescribed for a week after surgery, while steroids and artificial teardrops are usually prescribed for a month. There is a complete regime of pain relief in place and most patients are able to cope reasonably well with any post operative discomfort.

You should wait at least one week following your LASEK Laser Eye Surgery before beginning any non-contact sports. To help prevent infection, you will need to wait for up to 4 weeks after surgery before using lotions, creams, or make-up around the eye. You should also avoid swimming and using hot tubs or whirlpools for a month. Strenuous contact sports such as boxing, football, karate, etc. should not be attempted for at least 4 weeks after surgery. It is important to protect your eyes from anything that might get in them and from being hit or bumped. It is essential to protect your eyes from bright sunlight by using a good pair of sunglasses for at least 3 months after surgery.

During the first few months after surgery, your vision may fluctuate. It may take up to 3 to 6 months for your vision to stabilise after surgery. Most LASEK Laser Eye Surgery patients have a mild degree of dry-eye up to 3 months after surgery and can require artificial tears or rarely punctal occlusion during this period. Glare, haloes, difficulty driving at night, and other visual symptoms may also persist during this stabilisation period.

Your follow up check-ups for 6 months are included in the price of surgery. It is advisable to continue with annual eye health check-ups after that.

Laser Eye Surgery Technology

The Technology of Laser Eye Surgery

Laser Eye Surgery is a technology-driven procedure. Previous and older Laser Eye Surgery technology cannot match the results of modern diagnostic wavefront, femtosecond and excimer laser technology.

The surgeon has to understand this technology triad and use it to deliver excellent results and safety. Although technology-based, the results are still very much surgeon dependent.

The Vision Surgery and Research Centre uses some of the most advanced and time tested Laser Eye Surgery technology. Our technology partners are leading laser surgery companies in the world.

Wavefront Diagnostic Technology

The AMO-VISX Wavescan is the wavefront scanner used.

This is optimised to produce a very detailed and individual “fingerprint” of your individual focusing errors beyond what was previously possible, and beyond what can be corrected with glasses or contact lenses. This scan is used to generate the corrective shape to be sculpted on the eye by the excimer laser.

The scan has to meet rigid quality standards to be useful in treatment and produce better results than standard spectacle prescription based treatment. All Laser Eye Surgery patients at this centre are mapped with the wavefront scanner, and standard treatments are only used if the wavefront scan is not of a good quality.

Femtosecond Laser for Making Blade-Free LASIK Flaps

This technology has revolutionised the creation of LASIK flaps. We use the Zeimer LDV LASER which is the fastest femtosecond laser currently available. It uses the lowest energy levels to create the LASIK flaps and is currently almost 100 times faster than the Intralase laser. This laser does not cut tissue, but creates a flap by focusing and scanning its energy across the cornea. It is the gentlest of processes, with exquisite control and consistent flaps. Prior to this technology, a blade-based instrument was used to mechanically cut the flap. Compared to blade flaps, laser-created flaps are of more predictable thickness allowing for thinner flaps. This allows for the LASIK Laser Eye Surgery procedure to almost match the LASEK procedure in retaining the biomechanical strength of the eye increasing the safety and predictability of LASIK.

Excimer Laser for Sculpting the Eye to Correct Focussing Errors

Laser Eye Surgery started with the advent of excimer laser. We use the AMO VISX S4 IR LASER. This advanced laser system has been around for some time and has been continuously improved so that it is now the most time-tested and widely used system in the world. It is a variable flying-spot laser with iris recognition and cyclotorsional tracking system. These features mean that it can place the corrective shape to be sculpted with peerless accuracy on the eye. It can compensate for patient eye movement and maintain the accuracy of the LASER delivery throughout the procedure.

Richard

“The surgery took 15 minutes, was completely painless and I was home relaxing by mid-afternoon. I could see my vision improving!”