Human Eye and an Explanation Term Paper

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For candidates not considered good prospects for conventional LASIK because of extreme nearsightedness and who are leery of the long recovery period of PRK, phakic intraocular lenses can be implanted. "In these cases, a phakic intraocular lens may be used. This lens is implanted inside the eye and can effectively treat nearsightedness up to -20 diopters" (Randleman & Payne 2010, p.4). Intracorneal rings (thin plastic segments) implanted into the peripheral cornea to flatten the cornea can be used for individuals wary of the side effects of the surgery. While visual recovery is less predictable with the intracorneal rings, the procedure has the advantage of being reversible. However, it is only able to correct up to -3 diopters of myopia (Randleman & Payne 2010, p.4).

Because it is not considered necessary surgery, and because the conditions it is designed to treat can be corrective with less expensive glasses and contacts, most insurance plans do not cover LASIK. Having to pay $4,500-$5,500 is not uncommon, depending on the surgery or area of the nation where the patient resides (Ellin, 2008, p.1). Additionally, some candidates are not suitable for LASIK under any circumstances: younger or older individuals whose vision is still unstable; people who play traumatic contact sports involving blows to the face such as wrestling and boxing; people with autoimmune diseases (which can impede healing) and people with corneal diseases are not considered suitable candidates. Women who are pregnant or breast-feeding, people with insulin-dependant diabetes, and individuals with herpes simplex are also excluded (Halem 2002, p.2).

Patients with both near and far-sightedness may still need glasses after surgery due to age-related eye changes. It is typical that patients who were nearsighted for most of their lives and began to use reading glasses later in life will still require reading glasses after surgery. "In addition, LASIK results may not be as good if you either have very small amounts of astigmatism or very large refractive errors" (Halem 2008, p.1).

Patient controversies

According to some patients, the risks of the surgery, including seeing halos and the need for additional surgical adjustments for an over or under-correction of their vision, are often not made sufficiently clear. "It would have been nice if I'd known my advanced age (thirty-nine) might be problematic before I sat in the chair," said one woman, post-surgery, after complaining of chronic dry eye as a result of LASIK (Ellin 2008, p.2). "My consent form said: 'The patient understands that the benefit of the LASIK/PRK procedure is to have an improved uncorrected visual acuity.' I took that to mean that my eyesight would be 20/20. Most doctors, on the other hand, focus on the words 'improved uncorrected visual acuity'" (Ellin, 2008, p.2). "Within a month, something peculiar happened: The vision in my left eye started to change. At first, it only slipped to 20/20. A few months later, it was 20/25. After a year, my left eye had regressed to 20/40, the minimum needed to pass a driver's license test. Two years after I had LASIK surgery, my vision had deteriorated so dramatically that my doctor decided it was time to do a 'touch-up' (Ellin, 2008, p.2). Of the 835,000 patients who had LASIK in 2001, 5.8% needed additional surgery (Halem 2002, p.1).

The American Society of Cataract and Refractive Surgery reports a 95.4% patient satisfaction rate over its decade of post-operative research, based on upon nineteen studies involving 2,022 patients (Ellin 2008, p.1). However, severe complications have been reported: "Excimer laser treatments that cause too much reduction in the residual stromal bed have been indicated as a potential cause of a serious LASIK complication called corneal ectasia, which can severely distort vision and cause permanent vision loss" ("PRK," Refractive Surgery News, 2010). For other candidates, the surgery has been a career-maker or a career saver. "Nearly a third of every 1,000-member Naval Academy class now undergoes the procedure, part of a booming trend among military personnel with poor vision. Unlike in the civilian world, where eye surgery is still largely done for convenience or vanity, the procedure's popularity in the armed forces is transforming career choices and daily life in subtle but far-reaching ways. Aging fighter pilots can now remain in the cockpit longer, reducing annual recruiting needs. And recruits whose bad vision once would have disqualified them from the special forces are now eligible, making the competition for these coveted slots even tougher" (Cloud 2006, p.1). The military has benefited, as its total enrollment begins to decline overall, now qualified and experienced soldiers need not be denied positions based upon their eyesight.


Patients must decide for themselves whether the benefits outweigh the risks in their personal circumstances. They must also steel themselves to the possibilities of needing 'touch up' surgeries and having less-than-perfect vision afterwards. Touch-up surgeries can also be expensive -- running up to $300 for several procedures (Halem 2002, p.2). However, those who are happy with the procedure praise the freedom it has provided them, in terms of their personal, career, and lifestyle choices. Advocates allege that the risks of LASIK and other eye surgeries have been overstated. One pro-LASIK study "concluded that daily contact lens wearers have about a one in 100 chance of developing a serious lens-related eye infection over 30 years of use, and a one in 2,000 chance of suffering significant vision loss as a result. The researchers calculated the risk of significant vision loss due to LASIK surgery to be closer to one in 10,000 cases" (Boyles 2010). And as the surgical technology improves, claims of complications may decrease radically. Regardless, LASIK and other forms of corrective eye surgeries continue to be hotly-debated and wildly-sought after procedures in the field of ophthalmology.

Works Cited

Boyles, S. "LASIK Surgery: Safer than contacts?" WebMD. 2006. May 15, 2010.

Cloud, Daniel. "Perfect vision is helping." 'The New York Times. June 6, 2006.

May 15, 2010.

Ellin, Abby. "Lasik surgery: When the fine print applies to you." March 13, 2008. May 15, 2010.

"Facts about the cornea and cornea disease." National Eye Institute. Published by the National

Institute of Health. May 2010. May 15, 2010.

Halem, Dann. "The new facts about LASIK." Shape. 2002. May 15, 2010.

Kimball, J. "The human eye." Biology Pages. November 9, 2009. May 15, 2010.

"PRK." Refractive Surgery News. May 15, 2010

Randleman, J. Bradley…

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