1.0 INTRODUCTION
Today we always talk about the technology where make our live easy. The sophisticated technology today separated the whole world, and in the medical especially also move fast together with other development. Medicals are most important for our life, it’s because our healthy depends on a medical. Beside that, medical always bring chance for who concern about life and make our life always in the level of success. To achieve the purpose of medical field, those have been responsibility in this area always thinks the better technology or way to solve the various health problem happen today. Many researchers try to find the new technology in the medical where always satisfy our necessary. In the medical area, eye surgery gives more impact to us by helping who have the eye problem. For most people, vision is a simple matter; we move our eyes, roll them at our lecturers, and move them in all environments, whether bright or dismally dark, always without much complaint.
However, as people age, they often experience degeneration in their eyes, commonly in the form of floaters. The back regions of the eyes are made of a watery fluid called vitreous humor. When we age, the cells making up the membranes will commonly become detached and these small pieces of membrane, which are clumps of cells, will join the fluid, and can obstruct our vision. This has earned them the term floaters, because people see them floating in their range of vision. An eye is very important for a person. Without eyes we can’t see the beauty of a world, without eyes we cannot walk as free as always and without healthy eyes we can’t see things as clear as normal guy. Unhealthy eyes will burden our life instead of our body. It is because impulses that come from the things that eyes see cannot be translate by brain and the feedback that given from brain to eyes also maybe wrong. A Improvement in this situation always done to be satisfied our medical need. Eye surgery was started long time ago from the traditional method until now by the new technology. 2.0 THE HISTORY OF EYE SURGERY
Ancient surgical method started from community in earliest Greece , Mesopotamia , Egypt , China and India India
After Hippocrates the Greeks made the distinction between curable and incurable cataract, the latter of which was associated with glaucoma (meaning ‘greenish’). Though it was generally believed that glaucoma was caused due to some affliction of the vitreous humor, it wasn’t until 1622 when Richard Banister used the ‘hardness of the eye’ as a measure. Hippocrates also performed vitrectomy- the removal of the vitreous humor- to cure some illnesses, which may have included retinal detachment. Though refractive surgery was far fetched during this time, it is interesting to note the controversy surrounding the discovery of glasses. The Roman tragedian, Seneca, supposedly read all the books of Rome
The largest stride in the development of eye surgery before our own time was made during the Renaissance period- between the 13th and 18th centuries AD. The ‘couching’ technique for the removal of cataract was used all the way till the end of the Daviel’s method of cataract extraction (1748) 16th century. The radical break came with the method of Daviel in 1748, which is essentially the method in use today. Brisseau, St. Yves and Petit saw the possibility of removing the lens a few years earlier. Yet, for another 100 years or more the couching method was continued all over the world.
Mooren’s iridectomy in 1864 led to the modern method of cataract surgery. Iridectomy was also used as a cure for glaucoma. An incision was made in the iris to facilitate the flow of humor from the posterior chamber to the anterior chamber thereby releasing the forward pressure on the iris. Tonometers were used extensively since the mid 1800s to detect glaucoma by measuring the corneal pressure.
Clearly, the modern development of surgical methods was spearheaded by the development of sophisticated instruments. Carefully crafted optical systems, surgical tools and the development of artificial light sources led to the invention of the ophthalmoscope, refractometer, isoscope (to measure astigmatism), tonometer and other instruments. These led to the accurate diagnosis of eye diseases. Brucke and Kussmaul came close to developing the ophthalmoscope, but Helmholtz in 1850 finally invented the ophthalmoscope. Early illustrations of eye diseases were possible because of what the doctor saw through the ophthalmoscope.
By the early 1900s the development of lens implants had begun due to the development in plastics. By 1930 cataract surgeries involved the replacement of the cataractous lens with that of a plastic one. In 1968 ultrasound was used to remove the cataractous lens. By 1964 over 6 million people were wearing contact lenses made of plastic, which were much more tolerable than the earlier glass ones. The development of the laser resulted in the revolution that we are witnessing today.
3.0 THE HISTORY OF LASIK SURGERY
LASIK or Lasik (laser-assisted in situ keratomileusis) is a type of refractive laser eye surgery performed by ophthalmologists for correcting myopia, hyperopia, and astigmatism. The procedure is generally preferred to photorefractive keratectomy, PRK, (also called ASA, Advanced Surface Ablation) because it requires less time for the patient's recovery, and the patient feels less pain overall. However, there are instances where a PRK/ASA procedure is medically justified as being a better alternative to LASIK.
The LASIK technique was made possible by the Colombia-based Spanish ophthalmologist Jose Barraquer, who, around 1950 in his clinic in Bogotá, Colombia, developed the first microkeratome, used to cut thin flaps in the cornea and alter its shape, in a procedure called keratomileusis. Stephan Schaller assisted in this landmark procedure. Barraquer also researched the question of how much of the cornea had to be left unaltered to provide stable long-term results.
The general term for changing a patient's optical measurements by means of an operation is Refractive Surgery. Later technical and procedural developments included RK (radial keratotomy), developed in Russia in the 1970s by Svyatoslav Fyodorov, and PRK (photorefractive keratectomy), developed in 1983 at Columbia University by Dr. Steven Trokel, "the father of laser vision correction," who not only published the first article on laser correction but was also granted patents on laser surgery by the U.S. Patent Office. (RK is a procedure in which radial corneal cuts are made, typically using a micrometer diamond knife, and is completely different from LASIK).
In 1968 at the Northrup Corporation Research and Technology Center of the University of California, Mani Lal Bhaumik and a group of scientists were working on the development of a carbon-dioxide laser. Their work evolved into what would become the Excimer laser. This type of laser would become the cornerstone for refractive eye surgery. Dr. Bhaumik announced his team's breakthrough in May 1973 at a meeting of the Denver Optical Society of America in Denver, Colorado. He would later patent his discovery.
The introduction of lasers in refractive surgeries stemmed from Rangaswamy Srinivasan's work. In 1980, Srinivasan, working at IBM Research Lab, discovered that an ultraviolet Excimer laser could etch living tissue in a precise manner with no thermal damage to the surrounding area. He named the phenomenon Ablative Photodecomposition (APD). Stephen Trokel published a paper in the American Journal of Ophthalmology in 1983 outlining the potential benefits of using the Excimer laser in refractive surgeries. The first patent for laser correction of the cornea using an Excimer laser was granted to Dr. Steven Trokel.
The first patent for LASIK was granted by the U.S. Patent Office to Dr. Gholam A. Peyman on June 20, 1989, U.S. Patent #4,840,175, "Method for modifying corneal curvature," encompassing the surgical procedure in which a flap is cut in the cornea and pulled back to expose the corneal bed. The exposed surface is then ablated to the desired shape with an Excimer laser, after which the flap is replaced.
The first FDA trial of the Excimer laser was started in 1989. The laser was unavailable to any doctor other than the ten selected by the FDA for the Visx trials. The first use of the laser was to change the surface shape of the cornea, known as PRK. Dr. Joseph Dello Russo was one of the ten original FDA researchers who tested and got approval for the Visx laser. The LASIK concept was first introduced by Dr. Palliakaris in 1992 to the group of ten surgeons who were selected by the FDA to test the Visx laser at 10 centers in the Dr. Palliakaris theorized the benefits of performing PRK after the surface was raised in a layer to be known as a flap performed by the Mikrokeratome developed by Barraquer in 1950. The blending of a flap and PRK became known as LASIK, which is an acronym. It quickly became very popular, since it provided immediate improvements in vision and involved much less pain and discomfort than PRK.
Today, faster lasers, larger spot areas, bladeless flap incisions, intraoperative pachymetry, and wavefront-optimized and -guided techniques have significantly improved the reliability of the procedure compared to that of 1991. Nonetheless, the fundamental limitations of Excimer lasers and undesirable destruction of the eye's nerves have spawned research into many alternatives to "plain" LASIK, including LASEK, Epi-LASIK, sub-Bowman’s Keratomileusis aka thin-flap LASIK, wavefront-guided PRK and modern intraocular lenses.
This laser technique is small, but is gaining popularity. Most eye doctors are not familiar with the technique, but it is gaining more acceptance in the scientific community, as over 90% success rates have been reported. Because it has minimal side effects, and no damage to the retina have been reported in any eyes treated by the technique, laser eye surgery is now seen as a good breakthrough in destroying eye floaters.
Currently, the procedure has not been investigated thoroughly in peer-reviewed scientific journals and it is only performed by a handful of surgeons. Because it is a simple in-patient procedure that requires minimal risk, it will most likely be seen as a common solution to a most common problem affecting many people.
LASIK may one day be replaced by intrastromal ablation via all-femtosecond correction (like Femtosecond Lenticule Extraction, FLIVC, or IntraCOR), or other techniques that avoid weakening the cornea with large incisions and deliver less energy to surrounding tissues. The 20/10 (now Technolas) FEMTEC laser has recently been used for incision-less ablation on several hundred human eyes and achieved very successful results for presbyopia, with trials ongoing for myopia and other disorders.
4.0 TYPE OF LASERS
The lasers that are used in Lasik eye surgery are truly unique and use exceptional technology. Excimer lasers were created specifically for Lasik. The FDA has approved each type of laser, but some lasers are better than others. The biggest difference is the way that the beam is delivered to the eye and their ability to track eye movement.
There are two broad categories of laser including broad beam and scanning. There are two categories within scanning lasers including slit scanning and spot scanning.
4.1 Broad Beam Lasers
Broad beam lasers utilize a large beam diameter, ranging from 6 to 8 millimeters that cut the cornea. The use of these lasers shortens the amount of time that is necessary to complete the surgery. These lasers also reduce the risk of over correction due to pupil movement. The larger diameter makes the likelihood of complications more likely, but improved technique has eliminated most of this risk.
4.2 Slit Scanning Lasers
Slit scanning lasers use smaller beams. The beam is linked to a rotational device that has slit holes to enlarge the area that is being cut. Slit scanning lasers provide a more uniform beam and create a smoother cut. There is a slightly greater chance of over correction with these lasers.
4.3 Spot Scanning Lasers
Spot scanning lasers are referred to as “flying spot” lasers. These use a small beam of 0.8 to 2 millimeters. The beam is scanned across the cornea in order to create the area to be cut. Spot scanning lasers have potential to create the smoothes cut. They are also able to produce customized cuts and are able to treat irregular astigmatism.
5.0 RISKS, COMPLICATIONS AND BENEFITS
Laser eye surgery for vision correction can change your life for the better, but you need to be comfortable with taking a certain risk, as no medical procedure is totally risk-free and the results are irreversible.
Laser eye surgery has been performed for more than a decade now and over that time, the complication rate has proved to be generally low. Around 5% of patients report problems following it.
i. The most common problems occur during the first few weeks after surgery and include:
ii. Over- or under-correction, or residual blurry vision, which requires another ‘fine-tuning’ enhancement after three months.
iii. Dry eyes, or inability to produce enough tears to keep the eyes comfortable, especially after LASIK.
iv. Visual symptoms, especially after PRK, affecting night-driving ability, such as corneal haze, glare and/or haloes, starbursts around lights, blurry double vision or light sensitivity.
v. Eye sensitivity after PRK or other surface treatments.
vi. Other, less common problems include myopic regression (where eyesight changes back to the pre-surgery state), lower contrast sensitivity and less crisp vision, even with glasses or contact lenses.
vii. Visually threatening complications are very rare. But as with any other surgery, there’s always a slight chance of infection, especially within the first two days after surgery. It’s rare and more common with PRK than with LASIK. Infections can lead to scarring and, in extreme cases, blindness.
viii. As it’s a fairly recent procedure, the long-term effect of removing corneal tissue is unknown, but so far no studies have suggested that there’ll be complications in the long term. Most problems discovered so far occur in the first year after surgery.
The benefits are:
i. Clear natural vision. It means that with this laser eyes surgery (LASIK) people who have done it will get clear natural vision as normal person. Eyes vision will improve better and needless to wear eye contact or spectacles.
ii. Pain free surgery. LASIK surgery is a surgery that doesn’t feel any pain. If you do the surgery in the evening, you can go home eat dinner take the medication doctor given for your eyes and go to sleep. In the morning, your eyes will see clearly from before.
iii. Improvement in quality of life. Bad vision will not prevent you from becoming a pilot, professional athlete, or a part of the armed services.
iv. Eye related problems like a squint are corrected improving your appearance and enhancing your self esteem and confidence.
v. The surgery reduces allergies of the eye and irritations that develop from use of glasses or contact lenses.
6.0 CONCLUSION
LASIK eye surgery in which the surface of the cornea is reshaped using a laser, used to correct certain refractive disorders. As you know, when you have vision problems such as nearsightedness or even astigmatism, there is only one way to help solve this problem; removing and/or repairing your corneal tissue.
There is much talk today about laser eye surgery. This type of vision correction surgery is very effective and an easy procedure that millions of people today have already taken advantage of. Laser surgery is the best form of technology when it comes to correcting your vision.
If you are unsure as to how this laser surgery works, keep reading about this laser eyes surgery. It is quite a simple and fast procedure and within just a few minutes your vision is already altered for the better. Whether your vision is good or bad it all depends on the cornea tissue. These tissues determine how well you see up close or far away. How this procedure works is that a laser gently burns away the tissue around your cornea. Once this tissue is removed the laser then reshapes your cornea. Of course your cornea is reshaped in a different way for each person; this is how it works for everyone.
There is no easier way to correct your vision than with laser eye surgery. Laser eye surgery is a procedure that is available to everybody. You can find laser surgery no matter where you live. This type of surgery is effective with no matter what type of vision correction you require. Laser surgery is completely safe and you will find yourself with little if any side effects following a laser eye surgery. Slight eye irritation is the worst of the side effects that you will experience. If you are experiencing anything worse than this, it is important to see your eye doctor as soon as possible. Your vision is very delicate you do not want to jeopardize it.
Laser eye surgery can completely alter your life in a positive way. You have never seen like you will follow this surgery. The technology is amazing and can correct your vision within just a few minutes.
REFERENCES
2. Tahzib NG, Bootsma SJ, Eggink FA, Nabar VA, Nuijts RM. "Functional outcomes and patient satisfaction after laser in situ keratomileusis for correction of myopia." J Cataract Refract Surg. 2005 Oct;31(10):1943–51.
3. Walter KA, Stevenson AW. "Effect of environmental factors on myopic LASIK enhancement rates." J Cataract Refract Surg. 2004 Apr;30(4):798–803.
4. The Cataracts and Gone - and so is the Need for Glasses, by Matthew Shulman. US News and World Report December 17, 2007, page 64
5. http://www.\LASIK\LASIK - Wikipedia, the free encyclopedia.mht
6. http://www.allaboutvision.com
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