LASIK Eye Surgery
Abstract:
The human eye is used to view objects but some individuals have trouble viewing objects clearly. Commonly the problem is known as a refractive error. Solutions to correct refractive error are glasses, contact lenses and LASIK eye surgery. Three common forms of refractive errors are myopia, hyperopia, and astigmatism. These are defect in the eye or in a lens caused by a deviation from spherical curvature. Myopia is the inability to see things that are far in distance, nearsightedness. Hyperopia is the error in which one cannot view things that are near clearly, farsightedness. Astigmatism is a condition in which someone’s eye cannot focus. The start of LASIK began in 1848 with several complications and uncertainty. Over the years LASIK has developed but many are still concerned due to some complications. Complications continue to lessen as more surgeries are performed but many individuals still have fear about the surgery.
Introduction:
The human eye is composed of the iris, pupil, cornea, aqueous humor, lens, vitreous, retina, fovea, and the optic nerve as seen in Figure 1. One sees an object from the reflection of light which bounces off an object into the eye. Light initially travels past a thin layer of tears which begins to bring focus to the eye. Then light passes through the cornea, which bends the light through aqueous humor to the pupil. The amount of light that is trying to pass through the pupil will cause the iris to do one of two things. A large amount of light will dilate the iris and a small amount of light will contract the iris. The light passes through the pupil onto the lens which changes and takes a different shape based on the distance of the object and refocuses the light to which it passes through the vitreous and reaches the retina. The smooth surface located in the back of the eye, retina, is where the focused light of an object ends. The retina has several functions, the most important is photoreceptor which is a specialized nerve ending that convert light into electro-chemical signals (Loft 2011). These electro-chemical signals are sent through nerves inside of the retina to the optical nerve which carries the signals up to the visual part of the brain creating a clear image of the object. The light must be focused exactly on the center of the retina for the image to appear clear, if not the image will appear to be blurry to the human eye causing a visual impairment.
Of the 7 billion people in the world 246 million people live with a visual impairment (“World” 2012). 140 million impairments are result of a refractive error, the inability for light to focus properly, due to an irregular shaped cornea (“Refractive” 2009). Three common forms of refractive errors are Myopia, Hyperopia, and Astigmatism. Myopia occurs when the physical eye length is larger than the optical length, which causes the light to focus at a point in front of the retina as opposed to on the retina, as seen in Figure 2. Hyperopia occurs when either the eye itself is small in size or from a disease which weakens the focus power of the eye, causing the eye to focus on light just beyond the retina as seen in Figure 3. Astigmatism generates from a cornea that is shaped irregularly causing light to focus on several parts of the retina as seen in Figure 4. Refractive errors are capable of being corrected with a pair of prescription glasses, contact lenses, or Laser-Assisted in Situ Keratomileusis (LASIK) eye surgery. Figure 4: Displays the pattern of which light travels through an eye with Astigmatism
Figure 4: Displays the pattern of which light travels through an eye with Astigmatism
: Display of what happens when light enter the eye of someone with Hyperopia
: Display of what happens when light enter the eye of someone with Hyperopia

Body:
History of LASIK Eye Surgery:
The start of LASIK eye surgery began in 1948. In 1948, Doctor Jose Barraquer developed a technique for correcting vision. For this development Barraquer is known as the “father of modern refractive surgery.” When Barraquer lived in Bogota, Columbia his initial ideas involved removing more than half of the cornea and freezing it. In 1949, he then used a lathe to reshape the surface to an appropriate shape. The cornea was then sewn back in place. Barraquer experimented with a technique to create lenticules after freezing excised tissue. His purpose was to add or remove corneal tissue to see the effect it had on corneal shape. The procedure at the time was referred to as freeze myopic keratomileusis or MKM (Mantry 2005). MKM was difficult to perform and gave very unpredictable results. MKM involved a basic version of the microkeratome that is currently used in LASIK; MKM played a significant role in developing the technology currently used for LASIK.
Ten years later in 1959, automated lamellar keratoplasty, ALK, was created. ALK was used a modified microkeratome that created a flap at the front of the eye and also removed a wedge of corneal tissue to correct refractive errors. Like Dr. Barraquer’s method the results were unpredictable. Shortly after ALK was founded, a Doctor from Russia, Dr. Fyodorov, created a technique called radial keratotomy, RK. Dr. Fyodorov slightly changed the previous techniques to endow reliable outcome with vision correction. In the former USSR, fashioned radial cuts of 90% depth and varied the length to correct degree of myopia (‘radial keratotomy’). The first photorefractive keratectomy was performed by Marguerite McDonald in 1988 and Ioannis Pallikaris described LASIK in 1989 (Stuart 2012). With RK, the cornea was reshaped by the use of standard surgical instruments. A scalpel was used to remove portions of the cornea for reshaping to assistance in the correction of hyperopia, myopia, and astigmatism. The RK technique of Dr. Fyodorov was proven to be more reliable than previous techniques; however it was proved to be only useful for patients who had myopia or astigmatism. For thirty years the RK remained the most reliable technique, until the development of a function by Steven Trokel that involved a laser which removed the corneal tissue. This procedure is known as a photorefractive keratectomy, PRK, which was the first surgery that reshaped the cornea. It reduced the prospective pain and it became known as LASIK (Garg 2010).
Complications:
When LASIK first started to be performed on individuals there were a lot of complications. Klaus Ditzen, an M.D. of Germany, stated that the flat profile of the highly hyperopic corneas allows for little room in making the flap which will result in an increase in interface problems. Epithelial ingrowth is a common interface problem. Epithelial growth was reported up to four times as often as myopic LASIK. Loss of one line of best corrected visual acuity was found in 7 to 33% of the series presented. Three to seven percent lost greater than two lines of best corrected visual perception. Hyperopic astigmatism was also cited as difficult to correct since with astigmatic ablation some of the effect achieved by the hyperopic ablation is lost. Ring haze was another complication with high hyperopia.
LASIK complications were also discussed by Eduardo Arenas, an M.D. of Colombia. Arenas noticed complications that included history of glaucoma, a serious eye disease that may cause blindness, due to the increased intraocular pressure, IOP, necessary for the LASIK procedure. In addition Arenas noticed severe dry eye due to the potential for irregular ocular surfaces, and history of eyelid abnormalities that could hamper the pass of the microkeratome (Talley 1996).
LASIK should not be operated on patients with keratoconus because the corneal thinning can lead to a hole in the eye surface or an increase in corneal ectasia initiating progression of disease. Caution was advised when having LASIK eye surgery after penetrating keratoplasties because of the theoretical risk of perforation of the graft when the IOP exceeds 60 millimeter an hour. Arenas discourage LASIK eye surgery after hyperopic (Talley 1996).
LASIK complications most commonly result from problems with the micro-keratome. Enrique Suarez, an M.D. of Venezuela, reported that of about 4,000 LASIK eye surgery cases, 32 of the 43 complications were associated with the microkeratome. The 32 cases had complete or incomplete cap resection, which is mostly seen from blocking of the lid speculum. Suarez cautioned against using a suction ring during the ablation itself since the cap may stick to the suction ring and be pulled off after the ablation is complete. Using sharp microkeratome blades can prevent the complication known as epitheliectomy or a shallow cut resulting in epithelial removal only. If central islands occur, it was recommended to retreat the central 3.0 mm only after lifting the flap as a second procedure (Talley 1996).
Application:
Today, over 12 million people have received LASK eye surgery. The satisfaction rate is at 95% and it continues to grow. LASIK makes it possible for millions of people throughout the world to not have dependent on glasses or contact lenses. The decision to have LASIK should be approached with caution seen surgery is involved, some serious potential risks are associated. According to guidelines from the Eye Surgery Education Council (ESEC), less than 1 percent of LASIK patients experience serious, vision-threatening problems. LASIK complications now-a-days can include: eye infection, chronic dry eye and LASIK flap problems. Other complications that generally clear up on their own such as the eye heals, including halos, haze and glare. The ESEC says most LASIK complications can be treated and usually clear up within several months. Studies consistently show that LASIK complications decline as surgeon experience increases. Most people receive LASIK to achieve perfect vision of 20/20 vision. Others might want surgery to achieve 20/40 vision (the minimum visual acuity required to obtain a driver's license in most states).
Future of Lasik Eye Surgery:
Currently, LASIK eye surgery is used to correct refractive errors. In the future it could correct other forms of visual impairments such as cataract or glaucoma. LASIK surgeons have recently conducted studies that have focused on the corneal thickness after femtosecond laser surgery was performed on a number of patients. The study revealed that after testing three different thickness groups that the femtosecond laser would provide a thick corneal flap (Cy 2011). In recent years, LASIK surgery has had adjustments made in the procedure in regards to the ablation zone, area of the eye that is in need of treatment through LASIK, diameter of the eye. The ablation zone diameter has a range of six millimeters to seven millimeters, which allows the laser to shape a larger area of the cornea. The increase of the large the ablation zone has led to improving outcomes in LASIK surgery (Bailey 2007). However if there was a suggestion that would be more advanced than LASIK surgery, it would be visual prosthesis. The development of visual prosthesis would be major push forward and benefit all who possess any form of visual impairment from myopia to being blind. To replace LASIK eye surgery visual prosthesis is more time consuming, there would have to be a surgery that would require going under the knife to remove and replace the entire eye. That would also be an long recovery process compared to now, where LASIK is performed within minutes and patients have same day recovery.
Societal and Ethical Implications: The biggest ethical issue facing LASIK eye surgery are the aforementioned complication patients may suffer following the procedure. According to Mike Mitka of the Journal of American Medical Association, The Food and Drug Administration implemented launched an investigation in order to decipher whether the procedure needs to be over sought more intently. (Mitka 2012). This investigation is called the LASIK Quality of Life Collaboration Project, and it also involves the Department of Defense and the National Eye Institution. This investigation purpose is to give government and physicians a better understanding of the benefits and downfalls of the procedure. The three phase project began in October 2008 and will conclude at the end of 2012. Many people have considered LASIK eye surgery but have not gone through with it. The main reasons why: fear and cost. According to Nancy Groves of the Ophthalmology Times, the average income of a LASIK patient is seventy-five to one hundred thousand dollars. This shows that LASIK is affordable if it is made a priority with one’s disposable income. That being said, only four percent of those who fall in that income range get the surgery. This suggests that they do not deem it to be a necessary procedure. Health insurance companies feel the same way, as they view the surgery as a cosmetic enhancement and do not support it under their plans.
Since LASIK Eye surgery is becoming popular, a lot of surgeons tend to lower their prices in order to entice customers. This is not a strategy Teri Lo, .marketing manager, CareCredit, GE Consumer Finance, in Costa Mesa, CA does not agree with. She believes that lowering prices on the surgery will have a negative effect on business because people still have price-quality perception. Lowering prices has led to misunderstandings about the procedure and what it entails. In November of 2005, Florida’s Attorney General announced a settlement with Lasik Vision Institution for allegedly false advertising their price in their small print. This is why it is very important that extensive, detailed research be done by anyone who could potentially receive the surgery.
Conclusion:
One can certainly say that LASIK eye surgery had made vast improvements from the days of Dr. Barraquer to now. The procedure has developed and become the most popular surgery amongst individual in the United States. Even though LASIK eye surgery as a ninety-five percent satisfaction rate, post-surgery complications continue to be a problem. It is the hope of many people that LASIK eye surgery can continue to develop in the future ahead, and achieve bigger and greater things that will be highly beneficial for society.

Figures:

Figure 1: Several major functions are located in the human eye such as the Sclera which protects the structure of the eye.
Figure 1: Several major functions are located in the human eye such as the Sclera which protects the structure of the eye.

Figure 2: Display of what happens when light enters the eye of someone with Myopia

Figure 3: Display of what happens when light enter the eye of someone with Hyperopia
Figure 3: Display of what happens when light enter the eye of someone with Hyperopia

Figure 4: Displays the pattern of which light travels through an eye with Astigmatism
Figure 4: Displays the pattern of which light travels through an eye with Astigmatism

Work Cited
Bailey, Melissa D. “Outcomes of LASIK for Myopia With FDA-Approved Lasers.” Cornea 26.3 (2007): 246-254.
CY, Kim. “Factors influencing corneal flap thickness in laser in situ keratomileusis with a femtosecond laser”. Korean Journal of Ophthalmology. 25.1 (2011): 8-14.
Garg, Ashok, and Jorge L. Alió. Refractive Surgery. New Delhi: Jaypee Brothers Medical Pub,
2010. Print.
Groves N. How to beat the most common objection: pricing. Ophthalmology Times [serial online]. October 2006;31(19):94-96. Available from: Academic Search Premier, Ipswich, MA. Accessed October 31, 2012.
Loft, Evan S MD. Your Guide to How the Eye Sees. Web WebMd, 3 Nov. 2011. Web. 29 Oct.
2012.
Mantry, Sanjay, and Sunil Shah. "Refractive surgery: lessons to be learned." Clinical &
Experimental Ophthalmology Apr. 2005: 115+. Academic Search Premier. Web. 22 Oct. 2012.
Mitka, Mike. "FDA focuses on quality-of-life issues for patients following LASIK surgery."
JAMA: The Journal of the American Medical Association 302.22 (2009): 2420-2422.
“Refractive Error”. Mosby's Medical Dictionary. 8th edi. 2009. Print. 1 Nov. 2012.
Stuart, Annie. "LASIK-Past, Present and Future." EyeNet Magazine. American Academy of
Ophthalmology, 2012. Web. 01 Nov. 2012.
Talley, Audrey R. "Possible LASIK Complications Are Discussed." Ophthalmology Times
21.26 (1996): 42. Academic Search Premier. Web. 12 Oct. 2012.
“World Health Organization.” Vision Impairments and Blindness, June 2012. Web. 17 Sept. 2012.