Forty years ago laser eye surgery was revolutionary but today most individuals in the UK are aware of it and increasingly know someone who has benefited from it. They may not, however, be particularly knowledgeable about the operation itself. In this article we discuss the surgical process as well as answer the question how does laser eye surgery work?
Overview of Laser Eye Surgery
In a nutshell laser eye surgery involves reshaping the patient’s cornea so that sunlight enters the eye and hits the retina in a different fashion. In around 95% of cases the surgery will be successful on the first attempt and improve long sightedness, short sightedness or astigmatism.
Reshaping is achieved by the surgeon either cutting the cornea using specialist surgical instruments or by means of a laser. An alternative to cutting is to create a flap (also in the cornea) under which the laser is then focused on the eye. These different methods are described below.
Types of Laser Eye Surgery
A patient can currently choose from around six different forms of the surgery although it’s expected more sophisticated procedures will emerge as technology becomes more advanced (Wavefront, for instance, has only been introduced within the past two decades).
LASIK: By far the most popular form of laser eye surgery worldwide is LASIK (Laser-Assisted in Situ Keratomileusis). One of the first laser eye surgery processes to be introduced, it involves creating a hinged flap in the cornea using a blade. The surgeon will then remove very thin layers from the cornea using a laser.
Intra-LASIK: This involves the surgeon using the laser to cut the cornea rather the blade used in the previous standard LASIK procedure.
Wavefront LASIK: This is the most modern form of LASIK and as you would expect is becoming the most popular form of eye surgery. During a Wavefront operation a three dimensional scan (or ‘map’) is produced of the patient’s eye. This surgery is producing far more accurate than in the past and due to this, the chances of the patient gaining 20/20 vision are very much improved (hence the reason it has becoming so sought-after).
Epi-LASIK, LASEK and PRK: These three forms of laser eye surgery all involve removing thin layers from the cornea. However the actual cutting process isn’t as extensive as undertaken within a LASIK operation. During Epi-LASIK, for instance, the surgeon uses a thin plastic blade to produce a slit in the epithelial, with LASEK he or she will cut a similar slit using an instrument known as a trephine. With PRK the surgeon removes the epithelial covering of the eye completely. This regenerates itself within a matter of days.
What you can expect during and after the procedure
A laser eye operation can last anything from 15 minutes to 30 minutes, depending on the type of surgery involved and the patient’s individual prescription.
In most cases of laser eye surgery the patient’s vision will return after several hours of the operation being performed. They can then look forward to improved vision as the days go on. It’s possible to return to work and a regular routine with a couple of days of the operation being performed, provided the patient continues to bathe their eyes and follow the home care instructions provided by the clinic ie no contact sports for a particular period. With some forms of laser eye surgery (such as PRK) the patient has to wear a protective contact lense for up to four days afterwards.
Some patients complain of a halo effect around objects (particularly street lights) or problems with night vision but again these should reduce with the passing of time.
During LASIK surgery the eye is initially numbed via a local anaesthetic so that the patient doesn’t feel anything during the actual surgery. There is usually some mild discomfort post-operation. This usually involves dry eyes and for which eye drops are prescribed. The discomfort lasts just a few days.
Both PRK and LASEK patients take the longest to heal from this surgery. That’s because it takes time for the epithelial covering of the eye to heal. It can also prove more painful than the other procedures.
One of the most common questions put to a surgeon when a prospective patient asks ‘How does laser eye surgery work?’ is whether or not the operation will prove permanent or whether they will need to return for a similar operation in the future. In the vast majority of cases the operation is permanent. However patients with a high prescription may find that they may have to book for a repeat operation 10 or 20 years down the line. This is because the cornea naturally deteriorates with age.
It is not uncommon to be a little nervous before having a medical procedure like laser eye surgery but it is important that you know all the facts so you don’t worry unnecessarily.
Although laser eye surgery is becoming more and more popular each day some myths and misconceptions continue. Below are the most common myths and the facts below them.
Fact: When you for laser eye surgery, the eye surgeon will use eye drops to numb the eyes during the surgery, which takes almost 15 minutes for both eyes. During the surgery, you may feel some pressure and but not pain.
Fact: Depending on the procedure used for laser eye surgery, sometimes it is necessary for a flap to be cut and folded back. The underlying cornea is then reshaped using a computer-controlled beam of light that extracts an equal amount of tissue within a few seconds. The flap lifted from the cornea is then placed back to its original position. The cornea’s extraordinary bonding mechanism facilitates fitting of the flap without patches or stiches. Although it is an extremely delicate procedure, it is surgery nonetheless.
Fact: Vision threatening complications are rare during laser eye surgery, and so far, no one has reported a case of blindness after undergoing the procedure. Common symptoms include dry eyes, but it is a temporary problem which can be corrected by prescription eye drops. Before undergoing laser eye surgery, your eye surgeon will document all the potential risks and advise accordingly.
Fact: Laser eye surgery techniques such as LASIK use lasers that are classified as “cold” laser and do not emit any heat that can burn any part of your eye.
Facts: For over 25 years, laser eye surgery has been used to correct various vision defects. The first laser eye surgery treatment was done in The United States in 1987 and over the years the entire procedure has been refined. Side effects from laser eye surgery are usually minimal with complications being reported rarely. Millions of people have undergone laser eye surgery with positive outcomes being reported. The procedure is made relevant and more popular considering that it can be used to correct various eye defects ranging from shortsightedness to long-sightedness, thereby eliminating the need for glasses or contact lens.