how does laser eye surgery work Armadale

How Does Laser Eye Surgery Work?

The concept of surgically correcting vision was first recorded in the 1800s with the use of a spring-mounted mallet to flatten the cornea. Fortunately, laser eye surgery methods have progressed significantly since then, propelled further with the invention of tools such as the femtosecond and excimer lasers.

Refractive error, also known as ametropia, refers to a mismatch of the power of the eye’s focusing system (the cornea and the lens) to the length of the eyeball, also known as the axial length. As light passes through the cornea and lens of the eye, ideally it is focused, or refracted, to a sharp point on the sensory retina at the back of the eyeball – this is what we perceive as clear vision. In eyes where light comes to a focus either before the retina (as is the case of short-sightedness or myopia), behind the retina (as in long-sightedness or hyperopia), or at two separate points around the retina (as in astigmatism), vision is blurry and the patient is considered to have a refractive error.

The use of glasses and contact lenses helps to refocus the light entering the eye so that it will come to a clear point on the retina. However, these optical aids come with some disadvantages, such as life-long costs, cosmetic issues, and even some eye health risks. For patients seeking freedom from the inconvenience of glasses and contacts, laser eye surgery could be a very tempting option. So, how does laser eye surgery work?

 

How Does Laser Eye Surgery Work?

how does laser eye surgery work in Armadale

Laser eye surgery aims to adjust the focusing power of the eye through surgical means, essentially by reshaping the cornea. In addition to the refractive power of the lens inside the eye, the shape of the cornea is responsible for a proportion of the refraction of incoming light.

Details of how laser eye surgery works will be dependent on the specific technique used. We have a growing armamentarium of laser eye surgery methods which continue to expand the criteria of suitability, allowing more and more patients access to laser vision correction where perhaps just a decade ago they may have been deemed ineligible.

 

Photorefractive Keratectomy

Despite being one of the earlier methods, PRK continues to be a valuable technique still used today. As the excimer laser is applied to the inner corneal layers known as the stroma for the reshaping process, the superficial layer of corneal cells called the epithelium must first be removed. The removal of epithelium is performed either with an alcohol solution or manually with a hand-held instrument, which then exposes the corneal stroma. Guided by computer, the excimer laser then removes select areas of the cornea to adjust its shape, a process called photoablation. After the operation, the cornea naturally regenerates its epithelial layers as part of the healing process.

 

Laser-Assisted in Situ Keratomileusis 

Probably one of the most well-known laser eye surgery techniques, LASIK is similar to PRK in that it requires the corneal epithelium to be moved away in order for the excimer laser to access the underlying stromal layers for reshaping. However, unlike PRK, the LASIK method creates a flap of superficial corneal tissue which remains attached to the eye by a hinge. The flap may be formed using a manual bladed instrument or with another type of laser tool known as a femtosecond laser. Once the photoablation reshaping process is complete, the corneal flap is replaced over the eye and allowed to self-seal. A benefit of LASIK surgery is the shorter recovery time compared to PRK; however, one disadvantage is that LASIK is not suitable for thinner corneas as the creation of the flap reduces the amount of corneal tissue available for reshaping.

 

Small Incision Lenticule Extraction

SMILE® laser eye surgery is a much more recent method and is not yet widely offered across all ophthalmology practices in Australia. Hailed as a revolutionary, minimally invasive refractive surgery technique, SMILE® allows the biomechanical stability of the cornea to remain largely intact, resulting in faster healing times and a lower risk of complications. Unlike both PRK and LASIK, the epithelium is more or less undisturbed, and the corneal stroma is instead accessed via a small keyhole incision. A femtosecond laser is used to create a disc-shaped sliver of tissue within the stroma known as a lenticule, the dimensions of which are pre-calculated to correct for that eye’s particular refractive error. This lenticule is then removed through the keyhole incision, adjusting the cornea’s overall shape and curvature and thereby redirecting light to focus clearly onto the retina.

how does laser eye surgery work in Armadale AustraliaSo, there you have it – how laser eye surgery works. There are also other forms of refractive surgery that don’t depend on the use of laser technology; some of these techniques may be more suitable for certain patients, particularly those who have factors that make any sort of corneal disruption undesirable or those who have insufficient corneal thickness for reshaping.

Surgical procedures such as intraocular contact lenses (ICL) and refractive lens exchange (RLE) still achieve clear vision with independence from optical aids but without any significant interference to the cornea.

Patients who have been excluded from laser refractive procedures based on inadequate corneal thickness may find themselves eligible for refractive surgery through one of these other techniques.

The idea of surgery on such a delicate, sensitive organ as the eye can be daunting, but refractive surgery in Australia is associated with very high rates of success.

To discuss your eligibility for surgical vision correction, call us on (03) 9070 5753 and make an appointment with our rooms today.

 

Note: Any surgical or invasive procedure carries risks. Before proceeding, you should seek a second opinion from an appropriately qualified health practitioner.

smile eye surgery Armadale

SMILE® Eye Surgery – Everything You Need To Know

Laser eye surgery has been gaining in popularity over the last few decades. With advancements in both surgical tools and knowledge of the physiology and biomechanics of the eye, specialist ophthalmologists known as refractive surgeons are able to offer a greater suite of surgical vision correction options. The addition of newer refractive surgery techniques has also enabled more patients to be deemed eligible for vision correction procedures – whereas once we were restricted to simply treating short-sightedness, we now have procedures that can correct long-sightedness, astigmatism, and even address that age-related decline in near vision, presbyopia.

Short for small incision lenticule extraction, SMILE® eye surgery is one of the newest vision-correcting procedures available in Australia. As with many of the refractive surgery techniques, SMILE® laser eye surgery is based on corneal reshaping, which serves to redirect light through the cornea at the front surface of the eye such that it focuses to a clear point on the retina, providing sharp vision.

 

The Benefits of SMILE® Eye Surgery

The greatest benefits of SMILE® laser eye surgery arise from its minimally invasive nature. Older techniques such as LASIK and PRK, while still holding a valuable position in the suite of refractive surgery methods in modern-day, require significant disturbance of the corneal epithelium. As the laser reshaping process is applied to the deeper layers of the cornea known as the stroma, the superficial epithelial layers must first be removed; in LASIK this involves creating a hinged corneal flap which is later repositioned, while in PRK the epithelium is removed entirely and regrows during the healing stage.

smile eye surgery in ArmadaleDuring SMILE® eye surgery, the corneal epithelium is left intact and the cornea is reshaped from within using a femtosecond laser.

Because there is much less disruption to the tissues of the cornea compared to older techniques, SMILE® laser eye surgery results in an eye that is more biomechanically stable post-operation.

It also means a lower incidence of post-operative dry eye for susceptible patients, a side effect more common to techniques such as LASIK which involve greater disturbance to the corneal nerves.

The potential for flap-related complications is also eliminated with the SMILE® technique, as it is in PRK. Though extremely rare, the creation of the hinged corneal flap in LASIK opens the risk of complications such as inflammation at the flap interface, debris getting caught under the flap, or the flap losing its position. The uncompromised structural integrity of the eye after SMILE® makes it a great option for those who work in dirty environments or undertake work or hobbies that involve risk of physical trauma, such as in contact sports.

Recovery time after SMILE® is much faster than that in PRK, which requires about a week for the corneal epithelium to regrow. Compared to LASIK, SMILE® is a little slower in its visual recovery as it can take 1-2 days for vision to clear while after LASIK a patient typically experiences sharp vision immediately post-operation.

The SMILE® technique has been clinically proven to equal LASIK in terms of safety and accuracy. However, as with any surgical procedure, the final outcome and cost is largely determined by the skill and experience of the surgeon.

 

The SMILE® Procedure

Prior to undergoing any sort of refractive surgery, you will first have a comprehensive eye examination with the eye specialist and clinical team. The purpose of this is to determine which surgical procedure is most suitable, and will take into account factors such as your age, spectacle prescription, corneal thickness, lifestyle factors, and any other pre-existing eye diseases that may affect the final visual outcome. At this point in time, SMILE® eye surgery is appropriate only for patients with myopia, also known as short-sightedness, and can correct very high degrees of myopia even up to the double digits. You will also need to undergo a few additional tests to take specific measurements pertinent to the surgical procedure, such as axial length (the length of the eyeball) and corneal topography (mapping the surface of the cornea).

smile eye surgery in Armadale AustraliaDuring the procedure, the eye will be numbed with a local anaesthetic. You will be directed to fixate on a target light to keep the eye still and steady while the surgeon works.

A femtosecond laser is applied to create a precisely shaped disc of tissue, known as a lenticule, within the corneal stroma, which is then extracted from the eye via a keyhole incision no larger than 3mm. The result is a cornea that has been sculpted from within that now bends light to fall clearly onto the retina without the need for glasses or contact lenses. The entire procedure takes about 20 minutes, with the actual time spent under the laser only a few minutes long.

After the operation, you will be given detailed post-operative instructions on how to protect and care for the eye as it heals. You will have some medicated eye drops to aid this healing process, including a preventative antibiotic and an anti-inflammatory drop. The ophthalmologist will want to conduct a review appointment at least once or twice after your surgery to check the progress of your eye’s physical healing and visual recovery. Though vision may take a few weeks to fully stabilise, many patients are able to see quite clearly the day after the procedure.

As with any surgical procedure, SMILE® comes with some risks. These complications may include increased glare sensitivity, eye inflammation or infection, and over- or under-correction of the eye’s prescription.

To see whether SMILE® eye surgery is the perfect option for your laser vision correction, call us on (03) 9070 5753 book an appointment with us today.

 

Note: Any surgical or invasive procedure carries risks. Before proceeding, you should seek a second opinion from an appropriately qualified health practitioner.