Everything You Need to Know About Laser Surgery
Written by Dr. James Lehmann on 07/5/18
What is LASIK?
When we talk about eye surgery we are always invariably referring to LASIK Eye Surgery. Laser-Assisted in SItu Keratomileusis, commonly referred to as LASIK, is a laser-assisted eye surgery which is used to correct refractive errors of the eye. Lasik procedure uses a computerized laser to change the shape of the outer covering of the eye, the cornea. This allows the eye to focus light on the retina so that a clear image can be formed. Lasik is a blessing for those who are virtually blind without the glasses and are highly dependent on the contact lens as the means for avoiding glasses.
Ideal Candidate for Lasik:
You are an ideal candidate for LASIK if you are older than 18, have a stable eyesight or there have been no changes in the eyesight for at least one year. You have blurred vision without glasses and are either short sighted, far sighted with and without astigmatism and low night vision. Being older than 18 is important because before we reach that age, our eyes undergo a number age-related changes that can disrupt the changes brought about by the LASIK within a few months thereby rendering LASIK useless.
Patients with the end scale refractive errors such as short sightedness of more than −10 diopters, far sightedness of more than + 4 diopters and an astigmatism of more than 5 diopters are not considered good candidates LASIK. Some people might even have very thin corneas which also makes them unsuitable to undergo the procedure since it involves removing a small section of cornea further thinning it. There are certain eye diseases that make an individual unsuitable for surgery such as Glaucoma, in which the intraocular pressure in the eyes is raised, Strabismus, which consist of misalignment of the eyes or Herpes infection of the eye.
LASIK – Preoperative Assessment:
At Focal Point Vision (https://focalpointvision.com/), we meet with our patients to assess the need for LASIK and to answer all your questions and queries, so that you will be comfortable with the procedure as well as your surgeon. As part of the preoperative assessment, you will be asked to give a detailed ophthalmological history as well as undergo a complete eye examination. A number of eye test will also be done to look for any eye diseases, size, shape and the thickness of the cornea, as well as measuring the size of the pupil and the eye movements.
LASIK – Procedure:
LASIK procedure consists of anesthetization of one or both eyes undergoing the procedure. After anesthetizing the eye, an eyelid speculum is placed in the eye to keep the eye open for the duration of the procedure. The cornea is marked and the pupil is fixated with a suction ring. After that, a femtosecond laser is used to create a corneal flap. After the creation of the flap, it is moved away from the side. An excimer (ultraviolet) laser is used to reshape the eye centered around the pupil by removing the tissue around the cornea and the raised corneal flap is replaced.
LASIK – Post Operative Care:
The whole procedure, including the preoperative procedure, the surgery itself takes approximately 30 to 45 minutes. Immediately after the surgery the patient might feel mild discomfort for the first 4 to 6 hours and is recommended to close their eyes and rest or take a nap. Patients are also asked to avoid rubbing their eyes and looking directly into bright lights. The patient might also be prescribed antibiotics and steroids for 4 to 10 days. For dry eyes, artificial tears might be used for 2 to 3 months. In the follow up the patients are seen the day after the treatment and then one week later and further on a month later.
A difference can be felt immediately after the surgery and complete correction might take 3 months depending on the degree of refractive error and the amount of the tissue removed. For a higher degree of refractive errors and astigmatism sometimes a retreatment is required after the stabilization of the previous procedure. In this procedure, the flap is lifted again and ablated further. This procedure is known as Enhancement.
What are Refractive Errors?
Refractive errors of the eye are conditions in which the shape of the eye becomes fixed and does not bend the light adequately to form an image on the retina. This consists of 4 type of refractive errors and includes myopia (https://www.aao.org/eye-health/diseases/myopia-nearsightedness), hyperopia, astigmatism, and presbyopia. Myopia, also known as short or near -sightedness is the eye condition in which the near or close objects are clear and the distant objects are blurred. This is because the cornea becomes thick and the image is formed in front of the retina (the eye film) instead of on it.
Hyperopia (https://nei.nih.gov/health/errors/hyperopia) or far sightedness is a condition in which the cornea is too thin and bend light beyond the retina, which is why the far objects appear clear but the near objects appear blurry. Under normal conditions, the surface of the cornea is smooth and symmetrical to bends the light rays at one point on the retina on which a clear image is formed. Astigmatism (https://www.aoa.org/patients-and-public/eye-and-vision-problems/glossary-of-eye-and-vision-conditions/astigmatism) is another one of the refractive errors in which the shape and the surface of the cornea is irregular and therefore the image gets distorted.
Presbyopia consists of the age-related changes in the eye. They are also known as the aging eye condition. The lens in the eyes consists of fibers that are flexible and change while focusing on near or distant objects. As we age these fibers become stiff and do not fully focus on objects thus causing blurred vision. There is no treatment for presbyopia as no treatment and or surgery can halt age-related changes and the individual will require glasses as the vision continues to deteriorate.
If you have more question about LASIK surgery, visit us at https://focalpointvision.com/laser-cataract-surgery/. To learn more about Focal Point Vision, or to schedule an appointment, please call us at (210) 614-3600.