First performed in 1987, laser eye surgery is the world’s most frequently performed elective surgical procedure. It is estimated that over 18 million treatments have been performed to date and can result in complete freedom from corrective glasses or contact lenses.
Laser vision correction is surgery so any questions you have should be answered to your satisfaction before you undertake to have the treatment. It is important that you understand the options including the alternatives, the risks and limitations of the procedure itself, and feel confident with your surgeon before you commit to any surgical treatment.
Rakesh has been performing laser eye surgery for over a decade specializing in laser eye surgery for 18 months as Corneal and Refractive Fellow at Manchester Royal Eye Hospital in 2008 before moving to Queen Alexandra Hospital, Portsmouth as Consultant in 2010.
For patients with normal corrected vision prior to treatment and targeted for distance visual correction, over 99% will achieve the driving visual standard without spectacle correction (Annual audit – Internet Based Refractive Analysis) following one treatment of LASIK. The results are similar for surface laser procedures and are subject to continuous annual audit.
For patients who do not achieve clear vision following a first treatment, an enhancement may be offered to optimize treatment and is highly effective in treating any residual refractive correction. Fewer than 3% of patients* undergoing LASIK will require an enhancement procedure.
Suitable candidates for excimer laser correction should have healthy eyes with a good standard of vision when wearing glasses or contact lenses and a stable prescription within the treatable range.
The most common alternative to laser eye surgery is to continue to wear spectacles or contact lenses.
The surgical alternatives to laser eye surgery to correct refractive errors include intra-ocular lens implant surgery with a phakic lens implant, clear lens extraction or refractive lens exchange, corneal inlays and much less commonly, incisional corneal surgery.
Laser vision correction is a major ophthalmic undertaking that has the potential for complications that could affect your sight. However these risks and complications can be minimized by careful selection of suitable candidates for treatment, surgeon experience, and good compliance by the patient with the instructions before, during and after the laser procedure.
At the present time, excimer laser treatment is not recommended during pregnancy, nor for breast-feeding mothers. It can also be difficult to assess the healing response for patients with medical conditions such as diabetes and your general medical history must be taken into account in determining whether you are suitable for treatment.
Laser treatment can be effective in correcting myopia, astigmatism and hyperopia. However, it cannot overcome the problem of presbyopia. This is an age-related decline in the ability of the lens in the eye to change focus and enable you to read or undertake close work at the usual distance.
If you undergo laser treatment and become normal sighted, you will need to wear spectacles for reading once you become naturally presbyopic which typically occurs in the mid to late forties.
Treatment by either LASIK, LASEK or PRK can result in problems with scarring or haziness of the cornea, glare, haloes around bright lights, recurrent problems with the epithelium of the cornea causing pain or discomfort, infection, permanent long-sight or short-sight requiring correction with spectacles or contact lenses. In LASIK there can be additional complications related to the flap including ulceration of the cornea, loss or distortion of the flap, infection and inflammation under the flap.
The potential complications will be explained at the your initial consultation and examination. If you decide to proceed with treatment you will be given an Informed Consent Form that details the potential risks and complications that you must read and sign before proceeding.
Laser treatment may result in reactivation of old Herpes viral infection – if you have had presumed Herpes infection of the eye you should make this known.
Although the aim of excimer laser treatment is to improve unaided distance vision and reduce or eliminate the need for corrective lenses or spectacles, treatment can occasionally be unpredictable due to individual healing responses and the resulting level of vision cannot be guaranteed.
Excimer laser eye surgery works by reshaping the cornea, which is the transparent front of the eye. This encourages light rays entering the eye to focus successfully on, or close to the retina.
Z-LASIK involves the application of laser treatment to the deeper layers of the cornea under a protective flap, combining two different laser procedures. The result is a quicker return of vision and refractive stability following LASIK compared with LASEK or PRK.
Prior to the procedure, the team will spend some time checking the consent form and discussing the procedure, outlining what to expect. Should there be any anxiety, a gentle sedative can be taken orally prior to treatment.
After entering the laser suite, and laying down on the laser bed, a drop of anaesthetic is placed in the eye. A speculum is put in place to keep the eye open and tape protects the eyelashes. LASIK involves the use of 2 different lasers to treat the cornea. The first type of laser is called a femtosecond laser (Ziemer Z8) (http://www.ziemergroup.com ).This laser enables the procedure to be ‘blade-free’, enhancing safety and predictability. It is used to create a corneal flap, less than 1/10mm thin.
During this time the eye being treated is unable to see, this is normal and lasts for under 30 seconds. The flap is then lifted to expose the deeper tissue of the cornea.
The second laser, an excimer laser, is then used to gently change the shape of the cornea to the desired effect. The laser Rakesh Jayaswal uses is the WaveLight® Allegretto Wave® Eye-Q Laser (https://www.myalcon.com/products/surgical/wavelight-allegretto-wave-eye-q-laser/index.shtml ). The treatment is painless and typically takes less than 10 seconds. The flap is floated back into place and checked then eye drops are applied.
If the flap created is not judged to be satisfactory, the excimer laser treatment is not applied. It may be necessary to postpone the surgery, but this occurs only rarely. If it is not possible to create a flap using the laser, the surgeon may, using their professional judgment, offer the patient the opportunity to switch to a surface procedure e.g. LASEK.
Vision normally begins to improve after a few minutes and moderate vision is often achieved by the following day. Within 1 to 4 weeks most treated eyes have clear vision but it can take up to 12 weeks for the best optical quality to be achieved. There will be an imbalance in vision between treatment of the first and second eyes if they are treated separately.
The creation of the corneal flap carries the risk of complications not present with surface laser treatment. In addition to the risk of an unsatisfactory flap being created there is a possibility that the flap may be created without leaving a hinge in which case it will need to be carefully repositioned and very rarely stitched into place. In extreme cases complications due to infection, corneal perforation or other damage to the corneal flap could be sight threatening and may require further corrective surgery.
LASIK stands for Laser Assisted In Situ Keratomileusis.
It has become most common form of laser vision correction in the world. This is due in part to the fact that it is performed under a protective layer of corneal tissue, meaning there is less surface area to heal and less risk of corneal haze and scarring. It also allows for a more rapid visual recovery. LASIK is able to treat a broad range of refractive errors.
More than 15 million LASIK procedures have been performed worldwide, since it was first introduced in the late 1980s and has now become the most commonly performed procedure in the world.
The goal of LASIK is to reduce a patient’s dependence on their glasses or contact lenses. Current research suggests that over 99% of patients reach the legal driving standard without glasses or lenses following LASIK treatment.
LASIK is a virtually painless procedure and most patients only need anaesthetic drops to numb the eye prior to having this performed. The majority of patients say they feel no pain at all, though some mention feeling mild pressure or vibration during their treatment. Following the treatment there may be mild discomfort, but this is usually relieved by the use of the drops given at the time of the procedure, and by resting.
The procedure is very quick and involves creating a thin flap in the cornea and the laser is then applied to the mid corneal structure. The flap is then replaced and the vision recovers very quickly.
Z-LASIK uses the Swiss Z8 Femtosecond laser technology from Ziemer, arguably the most advanced femtosecond laser platform in the world.
The IntraLase Method has been used successfully on millions of eyes and we trust this advanced technology to deliver exceptional results.
The IntraLase Method is a 100% blade-free technique used to perform the critical first step in the LASIK procedure: creating the corneal flap. The creation of the corneal flap prepares the eye for the second step of the LASIK procedure, where an excimer laser is used on the inner cornea to correct vision.
The LASEK procedure involves preserving the extremely thin epithelial layer by lifting it from the eye’s surface before laser energy is applied for reshaping. After the LASEK procedure, the epithelium is replaced on the eye’s surface.
This is known as ‘surface’ laser, and is safer if your corneas are too thin or too steep for LASIK, or when it may be difficult to create a LASIK flap. The success rates for LASEK are very similar to those for the LASIK procedure.
SupraLASE™ is a surface laser procedure that uses a technologically advanced excimer laser to remove the surface cells before performing the reshape of the cornea to treat myopia and astigmatism.
By using a technique in which the eye is treated from beginning to end with lasers, this treatment is a ‘non touch’ treatment.
Photo Therapeutic Keratectomy laser surgery is done specifically to treat cornea injury or disease issues such as scars on the cornea or other types of corneal surface disease, including recurrent erosions syndrome of the cornea when other, more traditional treatments have failed. Similar to PRK, this type of eye surgery does not include vision correction. It is done for therapeutic reasons, to correct documented medical eye issues.
Advanced Topographic Guided Laser Treatment is one of the most precise methods of reducing higher order aberrations in patients with keratoconus. Following sequential, precise mapping of the cornea, the laser treatment is customised to accurately follow the topography to gently remove the peak of the corneal tissue in the most irregular areas. The cornea is then cross linked to stabilise it and ‘lock in’ the changes.
The major irregularities in the corneal surface caused by keratoconus can be reduced often improving vision , reducing discomfort with contact lenses and reducing the requirement to wear contact lenses.
Below are two maps showing a patient who underwent this technique with Mr. Jayaswal. Looking at the sagittal curvature map (top left) in each of the two scans, the shape of the cornea has changed from an irregular astigmatism to a regular astigmatism after treatment. This patient was able to avoid a corneal graft and resume life with just a soft contact lens.