Four Procedures Commonly Used in Refractive Eye Surgery
One of the first things put on in the morning and one of the last things taken off in the evening, glasses and contacts play a large part in the everyday lives of those who depend upon them to see clearly. These two types of corrective lenses allow for clearer vision, but glasses and contacts are also inconvenient. Sports, especially contact sports, are more difficult to play when glasses get in the way or break. For those who can wear them, contacts are an improvement over glasses; wearing contacts for 18 hours a day, however, is not healthy for the contacts or the eyes. Therefore, other methods are desired to correct vision.
Ophthalmologists have long dreamed of equipment and techniques to permanently correct refractive problems. For more than 100 years, doctors have been exploring the use of surgery to reduce or eliminate patient's dependence on glasses and contacts ["Refractive," 1997]. This dream came true with the introduction of refractive surgical techniques for the correction of myopia and astigmatism. In refractive surgery, various micro-surgical procedures are used to re-shape the front surface of the cornea. Four main refractive eye procedures are clinically being studied: radial keratectomy (RK), automated lamellar keratoplasty (ALK), photorefractive keratectomy (PRK), and laser in-situ keratomileusis (LASIK). These four common procedures in refractive eye surgery will be compared and contrasted while taking into account the limitations of comparison such as the patient and the extent of the correction needed.
Function of the Eye
The human eye is a complex organ with a primary function of focusing light on the retina to provide the sense of sight f...
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Optometrists have accepted vision therapy, which is a medical treatment for optical muscle disabilities, as a feasible treatment used for eye related problems; claiming the treatment can strengthen vision and give the patient the opportunity to understand visuals quicker and clearer (Press). Vision therapy originated in the 1950s and over the past 25 years, has gained popularity, mainly because of new technological innovations in the field of treatment. Generally, vision therapy is prescribed as a measure mainly for people between the ages of 3 and 18. With the results from a comprehensive series of eye tests, the optometrist can work with the patient using special instruments—prisms, filters, occluders, and eye lenses—and strengthen the eye muscles, thus improving sight. According to optometrists in favor of vision therapy, these methods of treatment using these instruments function as safer routes to repair eye disabilities. Although vision therapy can yield favorable results, the practice as a treatment for innate eye disabilities has been in hot debate lately; as it can exceed $8000 and insurance companies do not cover the treatment. For decades, insurance companies have refused to accept vision therapy as a legitimate method for repairing eyesight (Boink). Concomitant with lack of insurance, the cost for a full treatment can exceed $8000, and doctors cannot guarantee a successful outcome. Recently, parents of children with eye related disabilities, such as amblyopia (lazy eye) and strabismus (cross-eye), and doctors have attempted to cooperate with public schools to allow families access to school-funded doctors to practice vision therapy. With a tight budget, most schools cannot afford to supply vision therapy, and a...
In the past twenty years a large amount of bottlenose dolphin have been killed due to the tuna fishery. In the Eastern Pacific swim large schools of tuna, these shoals tend to be under herds of dolphins, for some unexplained reason. Because of this, fishermen can easily find schools of tuna. The tuna are being caught under purse seine nets, which encircles the shoals of tuna and then is pulled back on board the fishing vessel, catching both tuna and dolphin. Initially the mortality rate was 500,000 each year for dolphins alone. Although some efforts are made to encourage the dolphins to leave the net by backing down part of the net, which allows the dolphins to escape, there are still a large number of mortalities (Bryant). On the other hand, in the last few years there has been dramatic progress in stopping the fishing industries from using purse sine nets. It has been found that dolphins are in immediate danger of extinction if these fishing techniques don’t stop.
“Human trafficking coerces and persuades their victims to cross national borders in search of new jobs and better opportunities and after that they are forced into some sort of labor bondage” (At Issue: Human Trafficking 1). Even though trafficking is a problem in almost every country; poorer countries have a bigger problem with it because they are more desperate for work. Just in 2000, the U.S. enacted their first federal anti-trafficking law, called the Victims of Trafficking Protection Act (At Issue: Human Trafficking 1). Trafficking has just begun to receive notice on how big of a problem it actually is. “Proponents of strict anti-trafficking initiatives say that laws and prevention against trafficking are necessary in order to stem the growing tide of large scale organized crime that profits off of smuggling and trafficking” (At Issue: Human Trafficking 1).
Henry VII had won the English Crown in battle in what could be considered a glorious victory. There would be no need for his son to fight in such a battle, but that was a problem for young Henry. He wanted to achieve fame through military conquest and be considered a warrior king like many of his rivals. To meet this objective, Henry sought to capture the French throne for himself thereby extending his power and influence into continental Europe. Henry went to France, but was unable to make any significant gains financially or territorially. Instead he depleted his treasury and left England open for invasion on its northern border. English forces w...
What is Human Trafficking? “Human trafficking refers to the recruiting, transporting, enslaving, or receiving of people in order to exploit abuse them (Pubantz, Jerry, and Allphin Moore Jr.).” In nineteenth century France, prostitution was a common form of human trafficking.
Human trafficking has been entwined into the structure of governments, arms trade, drug trade, and even spreads as far as terrorism. For many years it has been a fact that the money that has been made by selling other humans to the highest bidder. It is also known that the organized crime operations generate one of the most profitable resources to the organization. These organizations use this money for theirs or other’s crime and end up in the hands of drug lords. Drug lords, in order to promote their own business give money to support terrorist groups and activities. Security after September 11, 2001 has recognized human trafficking as a national and international security risk.
Glaucoma is a common and important health problem. It is one of the leading causes of blindness in Western Society (Hoskins & Kass, 1989). It is responsible for ten percent of all blindness in the United States and continues to be the second or third most common cause of blindness in the world (Bunce, Fraser, & Wormald, 1999). It is estimated that two million people in the United States have been diagnosed as having glaucoma. Glaucoma is known to affect about two percent of Caucasians beginning at the age of 40 with an increasing risk for those over the age of 60. This risk is especially high if a member of the family has glaucoma or diabetes. Further, there is a higher risk of a glaucoma diagnosis for African Americans over the age of 40.
International Union for Conservation of Nature and Natural Resources, n.d. Web. 29 Mar 2012. http://www.iucnredlist.org/apps/redlist/details/20731/0
Cataract surgery may be the most commonly performed procedure around the world, but not every case is routine; many patients present with retinal or corneal conditions that require surgeons to take extra precautions before, during and after surgery.
Spigel, Lynn. 2001 Welcome to the dreamhouse : popular media and postwar suburbs / Lynn Spigel Duke University Press, Durham, N.C. :
According to estimates, more than 700,000 people are trafficked every year for the purposes of sexual exploitation and forced labour. They are transported across borders and sold into modern-day slavery. Over the past decade, trafficking in human beings has reached epidemic proportions. No country is immune. Clawson (2009) discusses how the search for work abroad has been fueled by economic disparity, high unemployment and disruption of traditional livelihoods. It recognizes neither boundaries nor borders. Consequently profits from trafficking feed into the casket of organized crime. Trafficking is fueled by other criminal activities such as document fraud, money laundering and migrant smuggling. Because trafficking cases are expansive in reach, they are among the most important matters. (Clawson 2009)
Human trafficking is a form of slavery, forcing victims to engage in sexual activities and labors against their will. These activities can be taken place through force, fraud, or constraint. Human trafficking is not just affecting one group of people, it is a worldwide issue, affecting all different ages, genders, ethnicities, and socio-economic backgrounds. Human trafficking is such an immense problem, apprehending the true size, knowing how to help, and how to keep the issue from reoccurring. Human trafficking is and is still becoming such a serious issue that something needs to be done about.
Boyers, Lindsay. "Genetically Modified Foods." SF chronicle [San Francisco] 03 03 2013, Demand Media n. pag. Print.
Did you know in the world there are more than 90 species of whales, dolphins, and porpoises? (WDC) The dolphin is a very important animal to the ocean and there are many different types to discover. In order to learn about dolphins, it is important to discuss where they live, their appearance, and what they eat. Some helpful words to understand are “dorsal fin”, a dorsal fin is the top pointed fin on the dolphins back, “flippers”, a flipper is a flat fin that dolphins use to swim, and “echolocation” is a tool dolphins use to find food by sounds bouncing off of objects (dictionary.com).
...r. Even though they live in the ocean all their life and also amusement parks, dolphins are mammals, not fish. That makes them very intersting animals because of all the charactics that they have that people would have never known about. Dolphins are by far the most intelligant marine mammals in the ocean.