M3 PBL Blog

Soon Zhou's Reflections

2009-08-22T09:31:00.005-07:00

From this PBL activity, I have learnt how to be selective in obtaining and presenting them in a proper way such that it is more directed towards the research question we are doing. This is helpful as it provides me with an organized flow of thought and ensures that the group is progressing towards the right direction. Also, I have learnt how to evaluate my thoughts using mindmaps as it allows me to expand and broaden my scope of thought, hence, considering all the aspects of the question itself.

I think that I have done well in organizing, processing and evaluating all the information gathered so that it only the useful information would remain and the group would not be confused in our direction. Also, I think I have also done well in presenting our solution and our research through a methodical and structured way so that the reader would be clear about our research, our decisions and our results.

What I could have done better was to include primary sources in my scope of research as all my information is gathered from secondary sources, hence, being less reliable. I think that I could also be better as a leader in coordinating the group such that the pace at which everyone is progressing is the same since we were unable to progress to the next stage of our research when a part of the information was not gathered yet.

The main difficulty in the PBL was having collated all the research we have done into the report as I would need to present it in a formal and informative way, yet, could be easily understood by others. Since Ms Chua stated that the report was somewhat like a book, I decided that I write it like a guidebook for people to understand LASIK more which helped me a lot when doing the report. Also, the mindmap was also a headache as I had to categorize all our findings into proper classes and summarize them; I had to spend time thinking through how I would compare each data and to see their similarities and differences. Trying to get some members to listen properly to instructions and not do things the way they preferred was also a problem, I solved it by processing and editing what they have done.

Tuck Ging's Reflections

2009-08-22T09:31:00.003-07:00

Personally, I feel that I did well in meeting deadlines and designing the brochure, our final product. I tried to complete my tasks by the deadline given and I succeeded. However, I could have submitted my work earlier or did a better job of it instead. I could also have designed the brochure better but I was sick and busy for the past few days doing homework and studying for tests. I faced the difficulty of balancing between school work, co-curricular activities and the various projects. I wanted to do the best for each aspect, but I end up neglecting one or another. So, I decided to draw up a schedule so that I can plan my time well.

Fangxu's Reflections

2009-08-22T09:31:00.001-07:00

I've learnt that there are many cases in which the situational factor has affected the outcome greatly, which can

be seen from the countless examples of people who done research on the topic and went for lasik because the

odds are in their favour, but were not pleased with the results because of the inexperience of the optician who

performed the surgery. Thus, it is more important to be in control of what is varying in any circumstance as they

would decide the final outcome. I have summarized the imformation from many sources and deleted stuff that

are not significantly important. However, I could have done more research so that I could understand the

outcomes of lasik better because statistics do not show the seriousness of the problem. During the PB

process, the information on some website are either too vague or disorganised, it took time to understand and

summarise.

Andrew Sung's Reflections

2009-08-22T09:30:00.001-07:00

2. Have you done PBL before? If yes, provide a description of how it a carried out.

I have done PBL in the previous term. We had to design and build a heat exchanger and consider all the factors needed to build it. In the end, we managed to effectively construct our heat exchanger and it could work thus we were pleased with what we have done.

12. Describe in detail how the group went about working on the PBL (from beginning to the end).

Firstly all our group members were searching for an appropriate problem statement that we could really focus on. Finally we decided on: How accurate are risks of surgeries shown by LASIK and how effectively are they conveyed?

We thought such a problem statement would allow us to assess and evaluate the effectiveness of hospitals, not just those of the government sector but also personal hospitals, on whether they could minimise the risks posed by LASIK to the patients. We were also very interested in how well hospitals were informing patients on LASIK and whether the patients fully understood the risks they were taking because we found that it would be really funny if the patient goes for LASIK without understanding the full implications because either the doctors did not inform him or he did not bother to know the risks he were taking. Moreover, we wanted to know about the risks posed by LASIK too because it seems very good to improve our eyesight and not have to wear glasses again, but rather, we want to know what would happen to us should we embark on the LASIK journey and whether there were any remedies for LASIK problems.

Then we did a mind map on our problem statement so that we would understand it better and found out that we had to concentrate on different procedures of LASIK as there were many and thus our group leader assigned each of us to research on different procedures of LASIK and record the importance of each procedure, who it was targeted at, how it was done, what were some of its side-effects, whether there were any solutions to problems caused by it, and whether there were any alternatives to this procedure. With all our data collected, we then discussed about the different types of LASIK that could be used in surgery and which method was the best.

13. Describe some of the difficulties that you faced during the PBL and how you or the group went about solving them.

Our group had lots of problems communicating because each of us had different timetables and other priorities too. Hence we had trouble sharing information with one another and sometimes even had trouble trying to agree on a certain thing. From this experience, I feel that we should take an active role in helping one another out because some of us may not be available and others thus have to cover him and help him out. As such, I think that being in the class really helped a lot because we could easily communicate and tell each other what has to be done.

14. In what ways has the PBL helped you to understand the topics taught in this module?

The PBL covers important topics such as refraction and lens because these 2 topics are usually associated with our eyes. I have understood more about refraction after the PBL due to lots of reading about how light rays are refracted through the various layers in our eyes and also about lens because the light rays are converged to form an image in our eyes too. Moreover, the PBL also lets me learn more about the various techniques of LASIK and understand how we can adjust and alter our eyes so that we are able to perfect eyesight, as well as how people having short and far sightedness experience different problems in their visions.

On top of that, I think that what the PBL has benefited me the most is training my research skills. I had to read up on lots of material and take out what was important and also paraphrase lots of stuff because we wanted to write our own report. It was quite an experience but I think it was worth it because I had great time learning about LASIK, which I think is extremely interesting and probably the reason why there is a large number of eye surgeons and ophthalmologists in Singapore. Thus I felt that the whole PBL experience was both beneficial to my learning of this module and my researching skills.

15. In what ways has PBL made learning more interesting for you? How has it motivated you in your learning?

PBL has allowed me to explore various areas of studies and I am not limited to just dead facts as when I study from notes and textbooks. I get to know more about the thoughts of the different people undergoing LASIK too: the patients, the surgeons, experts and even the people who are not undergoing LASIK. Some people are very supportive of LASIK whereas others do not really find it reliable. Hence I get to hear both sides of the story and varying views on the topic. Moreover, I also had lots of fun watching a video whereby a doctor was encouraging the public to go for LASIK whereas he was wary of the dangers of LASIK. Thus it was rather ironical.

PBL has motivated me to work hard on it because I want to do well in it. I have researched very widely on the topic because I want to get everything I can find about it. Thus it has been very encouraging to do PBL.

16. How has working with others benefitted you? What were you able to learn from each other?

Working with others allows me to cultivate my teamwork spirit. I had to coordinate a lot with my friends and all of us had to be aware of what we were supposed to do so that we would not get mixed up and feel lost about what we have to do. Moreover, we also wanted to prevent each other from doing the same thing and thus wasting each others time. I was able to learn a lot from what others have done because we were doing on different procedures and hence were presenting on different stuff. Hence it was really enriching to be working together on a project and I feel it is better to have a group working on a project than individuals because the workload can be divided and everyone can share their ideas. And most importantly, we really enjoyed each other.

17. In what ways did the PBL require you to view the problem from multiple perspectives?

As we were researching on both the advantages and disadvantages of various LASIK procedures, hence we could view each procedure with both a positive and negative mindset. This was very useful because we did not immediately say that this procedure was good or bad just by looking at it but had to think before we made our opinion. It was not as easy as looking at drugs and say that it is bad. Moreover, different group members all had differing opinions and hence we had lots of ideas and multiple perspectives from everyone and all of us could argue our points and it was kind of a debate thus it was very enjoyable.

18. In what ways has PBL enhanced your understanding of how real-world problems are solved?

The PBL emphasizes a lot on teamwork and social skills. This is very similar to problems in our real-world because we find that we usually need to coordinate a lot with other people and lots of negotiation and discussion has to be done before something is agreed. For example, the Singapore government itself often needs to go to Parliament and such to discuss certain issues related to Singapore and how to solve the problems. Hence our PBL was very much like that in the sense that we were doing lots of discussions and were each putting forth our views such that we found ourselves at times agreeing but at other times disagreeing.

19. In what ways can you apply the knowledge/skills learnt in other areas?

I have certainly learnt many important skills during the course of the PBL. Technically, I have learnt different software and how to do it efficiently, such as mind maps, online surveys and also researching tools. I find it very convenient to research now due to the vast amount of information on the Internet and am pleased with what I have found. Problem solving skills have also definitely been improved and now it becomes instinctive for me to look at a problem at different areas so as to fully understand and produce the ideal solution for the problem. Besides, through mind mappings, I have learnt to be more organized and concise with my points and thoughts. I also find I can apply these skills to other subjects such as mathematics whereby everything needs to be clear and concise. Furthermore, a time management skill is gained too. As all of us have very tight schedules, I think that being able to meet datelines nonetheless is a commendable feat.

20. In what ways were the blogs (yours and other groups') useful while working on the PBl activity?

Blogs are easy editing tools and allows us to post lots of information for others and ourselves to read. It is also very convenient to surf other groups’ blogs to read up on what they have done so that we can get an idea of the standard of other groups. Furthermore, I found it very good to post and read comments which I felt helped us a lot in letting us know our weak areas and what we can do to improve on our work. Overall, it was good to use blogs not only as a medium to communication but also as a source of information.

21. Describe some ways in which the web 2.0 tools (e.g. Wiki, Blog, Chat tools, bubbl.us etc.) have been useful for the PBL?

I really feel that all these web tools enhanced our learning process. The wikispaces allowed us easy access of materials, bubbl.us made it easy to construct mind maps which were effective in our learning and chat tools like msn messenger allowed fast and convenient communication. Also, I find it very good to be able to use such technology as they allow us to study faster and better.

22. In the PBL, you were required to construct mindmaps, which went through a few rounds of editing. In what ways has the mindmap and the process been useful in helping you to solve the task for the PBL activity?

The mind maps allowed me to understand the problem statement better because I could expand on certain areas that I was not really sure about and also made it easy for the whole group to share their ideas because everyone could put in something. Furthermore, the editing of the mind map allowed us to also decide on what parts of the PBL to include and what to exclude, hence it made the group more focused on the problem statement.

Thus thanks to the mind maps; I was better able to understand what the PBL demanded to us and what we had to do. Three cheers to it!

23. After doing the Learning Needs Survey (your responses here), you would now have a better understanding of your learning style (description found here). In what ways has the PBL activity catered to your style of learning?

I love to look at diagrams and the PBL certainly offers it as there are lots of mind maps to look at which help in my learning. Moreover, I find that I study better with all the information and hence with the PBL, I can get everything I wanted and it has been really beneficial to me.

24. After doing the Learning Needs Survey (your responses here), you would now have a better understanding of your learning style (description found here). In what ways has the PBL activity NOT catered to your style of learning?

I find that the PBL has been largely catering to my learning style.

Product

2009-08-22T09:23:00.001-07:00

We have decided to do a brochure of the LASIK centre we are going to set up as it shows what the benifits of our surgeries are and also our research on the history of LASIK and its surgeries. It is also informative in telling patients whether they should be going for LASIK surgeries if they were to have some medical disorders beforehand.

The first picture shows the coverpage on the right and last page on the left while the second picture shows the second page on the left while the third page is on the right. This is because the brochure is folded.

Final Mindmap

2009-08-22T05:42:00.001-07:00

Recommendation Report

2009-08-21T21:46:00.000-07:00

Introduction to LASIK

LASIK or laser-assisted in situ keratomileusis is a form of eye surgery which is able to cure myopia, hyperopia as well as astigmatism. All LASIK surgeries make use of the latest technology to alter the shape of the cornea in the eye by removing, shrinking or expanding tissues in the eye to solve these problems. Today, many people resort to LASIK eye surgeries to solve their eye problems so that they would not need to wear glasses or contact lenses since it is a nuisance in our daily lives. However, there are many types of LASIK eye surgeries which are targeted to different medical disorders, make use of different tools and involve different set of side-effects. The main issue is that many people are not fully aware of the risk they are taking when undergoing a LASIK surgery, hence, putting themselves in potential danger. There are mainly 5 LASIK surgeries, namely Automated Lamellar Keratoplasty, Photorefractive Keratectomy, Laser Thermal Keratoplasty, Conductive Keratoplasty, Radial Keratotomy.

Surgeries

Automated Lamellar Keratoplasty

Function

This surgery solves severe levels of myopia or mild levels of hyperopia.

Procedure

Firstly, the doctor calculates the shape to cut according to the patients eye(s). The eye is then anesthetized and a ring is fixed so that it remains opening. A microkeratome is then used to incompletely cut a thin flap of cornea so as to expose the layer of tissue below . Then, the microkeratome is used again to carve the right shape in the cornea so as to change the shape of the eye lens. The flap is then replaced for it to heal.

However, if the patient is hyperopic, the flap is replaced back without removing anything. This is because the cornea stiffens during recovery.

This operation usually takes less than an hour.

Recovery

Just 24 hours after the operation, patients are almost healed and able to see clearly. Besides, patients may feel very comfortable after the surgery although it may take months to regain vision stability. Ideally, the patient will have perfect vision after the surgery.

Possible Side-effects

Glare, inability to wear contact lenses, infections, corneal scarring, over or under-correction, inflammation can be the side-effects of Automated Lamellar Keratoplasty when the surgery is not done properly.

Pros and Cons

Automated Lamellar Keratoplasty is able to cure both myopia and hyperopia. Also, it only requires 24 hours for the cornea to heal after surgery. However, the risks taken when undergoing this surgery is high as it may lead to inflammation, infections and corneal scarring which may result in permanent, incurable and serious effects on the patients eye. Moreover, the time taken for the surgery is very long.

Photorefractive Keratectomy

Function

This surgery solves myopia, hyperopia as well as astigmatism. However, this surgery is best suited for patients with myopia and most patients would take this surgery so that they would not need to wear spectacles or contact lenses.

Procedure

The ophthalmologist will firstly execute a refraction to ensure the refractive alteration the surgeon will instruct the excimer laser is right. After the eye is numbed, the surgeon places a speculum in the eye to keep the eyelids apart and disallow movement. The patient stares at the twinkling light of a laser microscope and must keep his gaze steady on that light, staying motionless at the same time. After the the laser co-ordinatesis double checked, the eye surgeon takes away the epithelium with a sponge, mechanical blade, or the excimer laser. With the epithelium totally taken away, the surgeon will start reconstructing the cornea.

The whole process is approximately 10 minutes.

Recovery

A bandage contact lens would need to be worn on the treated eye to protect it and allow the healing process to take place; it also eases some of the pain of the exposed cornea. Anti-inflammatory and antibiotic eye drops needs to be applied to stop infection and reduce pain.

Possible Side-effects

If the surgery is not done properly, patients may experience glare, vision fluctuation, development of irregular astigmatism, vision distortion (even with corrective lenses), glaucoma, loss of best visual acuity, and, though extremely rare, total vision loss. A more common side-effect is long-term haze as it is resulted by aggressive healing processes which form corneal scars.

Pros and Cons

Although this surgery takes only a short time and is able to solve myopia, hyperopia as well as astigmatism, the patient is at a high risk of having long-term haze which would be a burden when we use our eyes. Also, total vision loss may also occur in extremely rare cases.

Laser Thermal Keratoplasty

Functions

Laser Thermal Keratoplasty is only able to help patients with mild hyperopia

Procedure

A Holmium laser (an infrared laser that emits heat to reduce the size of the corneal tissue) is used to reshape the cornea for low ranges of hyperopia. It is then used to heat the stromal collagen in a circle around the outside of the pupil. The heat results in the tissue becoming much smaller, forming a tightening effect. The side of the cornea is then pulled, causing the center to protrude. Because the cornea of a farsighted eye is too flat, this bulging effect, when carefully controlled, corrects the problem.

Recovery

After LTK surgery, subsequent appointments are needed for the very next day and for one week, one month, and 3-6 months after the procedure. An object in your eye may be felt for the first 24 hours following LTK. Eye drops can help relieve this, but only to a certain extent. Light sensitivity may also be felt for the first 24 hours and sunglasses may be advisable.

Possible Side-effects

There aren’t any serious side-effects to the Laser Thermal Keratoplasty as it is done using laser to change the formation of the cornea. The most common, mild side-effect would be over and under-correction which could be solved easily through another minor surgery.

Pros and Cons

Although this surgery is only able to cure mild hyperopia, causes much irritation to the eye during the first 24 hours and requires the patient to constantly revisit the doctor for checking, it is extremely safe compared to the other surgeries as the side-effects involved are not serious and can be solved easily.

Conductive Keratoplasty

Function

This surgery solves mild hyperopia and astigmatism. Most elderly undergo this surgery so that they do not need glasses when reading.

Procedure

A corneal topographer first maps the curvature of the eye. The eye is then anesthetized and a speculum is used to prevent the eye from blinking. After the treatment pattern is imprinted, a hand-held instrument with a tiny probe would then apply low-level radio frequency energy to the specific spots that form a circular pattern on the outer part of the cornea to a specific depth.The connective tissues in this area would then shrink causing the circular band to act like a belt that "tightens" and steepens the cornea, hence, changing curvature of the eye's surface.

The entire process last a few minutes

Recovery

There is no recovery period for this surgery as no tissue is removed from the eye; hence, no healing is required.

Possible Side-effects

The only side-effect is that the distant view of the patient might be affected to a minor extent. That is why doctors recommend patients who undergo this surgery to have good distant vision. However, if the patient has presbyopia, the condition of the eye may worsen after time. That is why doctors go through thorough checks to ensure that the patient does not have presbyopia.

Pros and Cons

This surgery last only a few minutes, does not require any form of recovery, does not remove any tissue from the cornea and has only one minor side-effect. However, the result might not be ideal if the patient were to have presbyopia, hence, doctors need to be cautious when allowing patients to undergo this surgery.

Radial Keratotomy

Function

Radial Keratotomy cures mild myopia and astigmatism. Patients should not have pathological myopia and degenerative changes caused by severe myopia, such as retinal tears or disease of the cornea, should not be present.

Procedure

The eye is anesthetised and a ring is fixed to it in order to prevent if properly positioned and flat. A precision calibrated diamond knife is used to make four to eight incisions perpendicular to the circumference of the cornea. To achieve high efficiency, the incisions usually reach deep into the cornea. This will cause the cornea to flatten and thus change the shape of the lens.

Recovery

Radial Keratotomy causes more discomfort and requires a much longer time to heal as compared other surgeries. The results are also more unpredictable. However, the incisions are suspected to never heal entirely. There have been reports of unhealed incisions even after 20 years of surgery. Patients have to return to doctors frequently for the first year in order to prevent these inflammation and infections to occur in the unhealed cornea.

Possible Side-effects

An improperly carried out surgery may lead to infection, inflammation, glaucoma, puncture of the cornea, loss of fine depth perception and more scattering of light.

Pros and Cons

Radial Keratotomy involves many serious side-effects including inflammation and infection. It is also troublesome as it requires the patients to revisit the doctor constantly within a year to prevent these side-effects from surfacing. Because this surgery is done by using a diamond knife, it may lead to unpredictable results if not carried out properly.

Research

Final refined research questions:

What are the best surgeries to be used when setting up a LASIK centre?

Which surgeries provide the least risks of having side-effects to the patients?

Which surgeries is less of a burden to the patients during recovery period?

Which surgeries are able to solve the most common eye problems?

Solution:

Choice

For setting up a LASIK centre, we have decided to use only Conductive Keratoplasty and Laser Thermal Keratoplasty among the five surgeries.

Side-effects

For Conductive Keratoplasty, the only side-effect is that the distant view of the patient might be affected to a minor extent. Although if the patient has presbyopia, the condition of the eye may worsen after time, this can be easily avoided through thorough medical check of the patient beforehand.

For Laser Thermal Keratoplasty, there aren’t any serious side-effects as it is done using laser to change the formation of the cornea. The most common, mild side-effect would be over and under-correction which could be solved easily through another minor surgery.

For the other surgeries, Automated Lamellar Keratoplasty and Radial Keratotomy involve side-effects such as infection and inflammation which is very serious and lethal to the eye. Especially when infection and inflammation may lead to eye diseases like retinitis pigmentosa which are incurable it should be avoided. As for Photorefractive Keratectomy, there is a high risk of having long-term haze which would be a burden when we use our eyes. Also, total vision loss may also occur in extremely rare cases.

Recovery

Conductive Keratoplasty requires no recovery at all since no tissue is removed from the cornea.

Laser Thermal Keratoplasty would only cause irritation to the eye for one day after surgery although it requires the patient to visit the doctor frequently for checkups for six months.

Automated Lamellar Keratoplasty patients would feel uncomfortable after the surgery and it may take months to regain vision stability. For Photorefractive Keractectomy, a bandage would need to be worn and anti-inflammatory and antibiotic eye drops needs to be constantly applied to the eye after surgery. Radial Keratotomy causes much discomfort and the eye might remain unhealed even after 20 years. The patient would even need to visit the doctor regularly for one whole year after sugery.

Functions

Compared to the other three surgeries, Conductive Keratoplasty and Laser Thermal Keratoplasty are able to solve only hyperopia and astigmatism but not myopia.

Summary:

Overall, Conductive Keratoplasty and Laser Thermal Keratoplasty is still the best choice although both are unable to cure myopia because the risk involved in both surgeries are much lesser and less serious than other surgeries and the it does not bring much problems to the patient during recovery stage compared to other surgeries too.

Eligibility

Pregnancy
Breast-feeding
Very small or very large refractive errors (Myopia up to -15.00 diopters, astigmatism from -0.50 diopters to -4.00 diopters and hyperopia from +1.00 diopters to +5.00 diopters are allowed)
Scarred corneas
Macular Disease
Autoimmune disease
Diabetes
Glaucoma
Persistent blepharitis

Statistics of LASIK

Around 30 patients per week per centre
80% of the patients were satisfied with their surgery
53% experince at least one side-effect
22% experinced side-effects which lasted more than 6 months

Definitions

Cornea- Clear structure that covers the front part of the eye. The cornea provides most of the eye’s optical power, while the crystalline inner lens, located behind the iris serves to “fine tune” the focus of the images.

Collagen- In referring to the eye, collagen is the protein fibrils within the corneal tissue that help sustain its shape. Some new refractive vision correction procedures heat these fibrils with a special laser causing them to shrink and change the shape of the cornea.

Myopia (nearsightedness)- The front curvature of the cornea is too steep in a nearsighted person, causing good reading vision but poor distance vision.

Pathological Myopia- Also known as degenerative myopia is characterized by marked fundus changes and associated with a high refractive error and subnormal visual acuity after correction. This form of myopia gets progressively worse over time.

Hyperopia (farsightedness)- Vision that results when there is too short a distance from the cornea to the retina. This can be caused by an eye that has a vertical oval shape or a cornea that is flatter than normal.

Presbyopia- Deterioration in the ability of the eye’s natural crystalline lens to expand or contract in order to focus on close objects.

Astigmatism- Uneven curvature of the cornea in which refractive light rays are bent out of focus resulting in distorted vision. Those people with astigmatism are usually born with the disorder and it does not worsen with age. Often occurs in conjunction with nearsightedness or farsightedness.

Glaucoma- Condition caused by excessive buildup of fluid inside the eye putting pressure on the retina. Glaucoma has few if any symptoms, but a simple, painless eye test detects the problem. If untreated, glaucoma can result in gradual, painless, irreversible loss of vision.

Inflammation- Redness, swelling, pain, tenderness, heat, and disturbed function of an area of the body, as a reaction of tissues to injurious agents.

Retinal- A form of vitamin A called retinal is responsible for transmitting light sensation in the retina of the eye. Deficiency of vitamin A leads to night blindness.

Macular Disease (Macular Degeneration)- Degeneration of the photoreceptors in the macula or central region of the retina. This area of the retina is responsible for central vision, used for reading, seeing faces, and so on. Often associated with aging.

Autoimmune- Of or relating to an immune response against one of the body's own tissues or cells.

Diabetes- Any of several disorders characterized by increased urine production.

Blepharitis- Common, persistent and sometimes chronic inflammation of the eyelids, resulting from bacteria that reside on the skin. Blepharitis is usually only a minor irritation.

Holmium Laser- Infrared (thermal) laser which its beam is cool and can remove small areas of tissue without affecting surrounding tissue. The Holmium laser is used to shrink the peripheral area of the cornea in order to make its shape steeper and correct mild to moderate cases of farsightedness. The laser works when moisture in the cornea absorbs energy from the laser pulses causing corneal tissue to heat up and shrink.

Microkeratome- Sophisticated surgical device used to shave a very thin amount of the cornea at a predetermined depth. Used to create the corneal “flap” which is lifted.

References

http://dictionary.reference.com/browse/inflammation?r=75 http://en.wikipedia.org/wiki/Myopia http://dictionary.reference.com/browse/autoimmune?r=75 http://dictionary.reference.com/browse/diabetes http://www.allaboutvision.com/visionsurgery/ck_ltk_eye_surgery.htm http://www.webmd.com/eye-health/radial-keratotomy-rk-for-nearsightedness http://www.docshop.com/education/vision/refractive/other-treatments/ http://www.lasikcomplications.com/RK-radial-keratotomy.html http://en.wikipedia.org/wiki/Radial_keratotomy http://www.healthcentre.org.uk/laser-eye-surgery/laser-thermal-keratoplasty.html http://www.visionrx.com/Library/enc/enc_ltkeratoplasty.asp www.visionrx.com/library/.../innov_laser_thermal.asp http://www.youreyeguide.co.uk/ltk/ltk-sideeffects-aftercare.html http://www.urologicinstituteofnj.com/images/stonesLaser.jpg http://www.visionrx.com/library/enc/tableac.asp http://www.lasikeyesurgerycorrection.com/lasik_risks.html http://www.webmd.com/eye-health/night-vision-problems-halos-blurred-vision-night-blindness

http://www.fdanewsalert.com/id580.html http://blogs.consumerreports.org/health/2009/07/lasik-eye-surgery-lasik-survey-getting-the-best-price-for-lasik-survey.html

http://www.realself.com/Lasik/reviews?sort=most_discussed http://www.surgeryencyclopedia.com/Pa-St/Photorefractive-Keratectomy-PRK.html http://en.wikipedia.org/wiki/Automated_lamellar_keratoplasty http://www.webmd.com/eye-health/keratoplasty-eye-surgery-alk-myopia-hyperopia http://www.the-lasik-directory.com/alk.html

http://www.eyecare-information-service.org.uk/lasereyesurgery/alk.html http://blogs.consumerreports.org/health/2009/07/lasik-eye-surgery-lasik-survey-getting-the-best-price-for-lasik-survey.html

Conductive Keratoplasty

2009-08-20T05:55:00.000-07:00

Diagnosis

-non-laser refractive
-correct mild hyperopia
-help old ppl reduce their need for glasses while reading
-uses low energy to reshape the cornea and restore near vision
-hand-held instrument with a tiny probe (smaller than a human hair) applies low-level, radio frequency (RF) energy to specific spots that form a circular pattern on the outer part of the cornea
-connective tissue then shrinks where the RF energy was applied, causing the circular band to act like a belt that "tightens" and steepens the cornea -- change in the curvature of the eye's surface
-no tissue is removed from the eye during a NearVision CK procedure that takes only a few minutes
-affects distant view to a minor extent
-doctors may run a test for patients to experience the results before doctors decide whether they should take the surgery
-patient must have good distant vision and above 40 years old
-no dry eyes
-long-lasting effects, but presbyopia may worsen

Procedure
-corneal topographer will be used to create a detailed map of the curvature of your cornea
-anesthetic eye drops applied to your eyes
-small support device called a speculum used to keep your eyelids open and prevent blinking
-treatment pattern on your cornea will be imprinted, showing where the radio frequency energy should be applied
-hand-held probe then is used to deliver the energy to a specific depth within the cornea at these spots
-entire process takes a few minutes
-slight pressure may be felt

Side effects
-None which are serious

Sources
http://www.moondragon.org/health/graphics/ckeyesurgery.jpg
http://www.allaboutvision.com/visionsurgery/ck_ltk_eye_surgery.htm

Radial Keratotomy

2009-08-15T20:28:00.000-07:00

Diagnosis

The patient is diagnosed with myopia and astigmatism (uneven cornea surface). Other than that, the eyes are normal, healthy with stable, mild to moderate myopia (up to 3 diopters). This patient will be eligible for Radial Keratotomy (RK) if he/she does not have pathological myopia, in which the eyeball fails to stop growing longer. Degenerative changes caused by severe nearsightedness (high myopia), such as retinal tears and abnormality or disease of the cornea should not be present in the eyes.

Usually, the patient is given the option to choose between several other types of operations. Photorefractive Keratotomy (PRK) and LASIK surgery have replaced RK by popular choice, yet it is still effective in reducing mild myopia.

Process #1

The eye is anesthetised and a ring is fixed to it in order to prevent if properly positioned and flat.

A precision calibrated diamond knife is used to make four to eight incisions perpendicular to the circumference of the cornea. To achieve high efficiency, the incisions usually reach deep into the cornea. This will cause the cornea to flatten and thus change the shape of the lens.

Recovery and results

RK causes more discomfort and requires a much longer time to heal as compared to PRK and LASIK. The results are also more unpredictable. However, the incisions are suspected to never heal entirely. There have been reports of unhealed incisions even after 20 years of surgery. These open wounds allow bacteria to settle and spread, thus causing much more harm like infections and inflammation to the eye. Therefore, patients have to return to doctors frequently for the first year in order to prevent these damages.

Possible Side-effects

-More scattering of light

-Loss of fine depth perception

-Puncture of the cornea

-Infection

-Inflammation

-Glaucoma

This surgery is still being performed albeit less popular than PRK and LASIK.

Sources

http://www.webmd.com/eye-health/radial-keratotomy-rk-for-nearsightedness

http://www.docshop.com/education/vision/refractive/other-treatments/

http://www.lasikcomplications.com/RK-radial-keratotomy.html

http://en.wikipedia.org/wiki/Radial_keratotomy

Laser Thermal Keratoplasty surgery

2009-08-15T02:58:00.000-07:00

LTK procedure

· Uses a Holmium laser (an infrared laser that emits heat to reduce the size of the corneal tissue) to reshape the cornea for correction of low ranges of hyperopia (farsightedness).

· The Holmium laser gently heats stromal collagen in a circle around the outside of the pupil. The heat results in the tissue becoming much smaller, forming a tightening effect.

· The side of the cornea is pulled, causing the center to protrude. Because the cornea of a farsighted eye is too flat, this bulging effect, when carefully controlled, corrects the problem.

Use of LTK procedure

Treat people who are far-sighted.

Advantages

Quick
Simple
Causes little pain
Low rate of infection
The recovery period is also much quicker, usually only taking around 2 days

Side-effects of LTK procedure

After LTK surgery, subsequent appointments are needed for the very next day and for one week, one month, and 3-6 months after the procedure.
Even an object in your eye may be felt for the first 24 hours following LTK.
Eye drops can help relieve this, but only to a certain extent.
Light sensitivity may also be felt for the first 24 hours and sunglasses may be advisable.

http://www.healthcentre.org.uk/laser-eye-surgery/laser-thermal-keratoplasty.html

http://www.visionrx.com/Library/enc/enc_ltkeratoplasty.asp

www.visionrx.com/library/.../innov_laser_thermal.asp

http://www.youreyeguide.co.uk/ltk/ltk-sideeffects-aftercare.html

http://www.urologicinstituteofnj.com/images/stonesLaser.jpg

http://www.visionrx.com/library/enc/tableac.asp

Mindmap

2009-08-07T00:50:00.000-07:00

Added the results of possible unprofessional procedure of surgery and compared with the response from patients about the dissatifactory outcomes.

Consequences if surgery is not proceeded properly

2009-08-07T00:13:00.000-07:00

Keratectasia - When a surgeon accidentally operates too deeply in the eye, the cornea will become altered and the patient may become blind.
Irregular Astigmatism - If laser rectification is not properly performed or when the eye is rough. The patients suffering from this error require more operation instead. At times seeing double is a result of a little inflammation.
Dry eye – This condition is generally common, but can be easily solved by eye drops.
Night Vision Problems – Such problems occur when doctors utilise conventional LASIK methods. The implication of night vision problems consists of many. One of the problems is blurry sight (glare and halos around objects). Distorted vision can happen at daytime too. However, at night it turns much more obvious and troublesome.
Over or under correction - Blurry vision or very slight seeing difficulties. Most of the time patients put on contact lenses or spectacles to correct this complication. Undergoing re-treatment is also an option.

Sources:

http://www.lasikeyesurgerycorrection.com/lasik_risks.html

http://www.webmd.com/eye-health/night-vision-problems-halos-blurred-vision-night-blindness

Mindmap

2009-08-06T08:12:00.000-07:00

Mindmap consisting of all the processes, side-effects of ALK and PKR surgeries as both are more common. Side-effects as shown by LASIK is compared with our findings.

People who are at risk and should not undergo these surgeries are also listed and compared with the list of people unrecommended by LASIK.

Responses from patients who have suffered severe side-effects are listed.

Statistical results of satisfactory customers of LASIK is added and as well as all the sources used.

Results of surgeries

2009-08-06T07:30:00.000-07:00

LASIK's actions

- with an adverse-reaction risk factor in excess of 5% (patient dissatisfaction) rate at six months, nobody is doing research on the procedure’s long-term quality-of-life

- involves either blade or laser-cutting of flaps in the corneal surface layer that patients complain never heal

- 80 percent, reported being "highly satisfied" with the results

- 53 percent of respondents experienced at least one side effect, such as halos, light sensitivity, or blurry vision

- 22 percent still had problems six months after the surgery

Patient response
- "Wish I would have been explained fully what could happen, how long procedure could last"

- " I did my research beforehand: spoke with prior patients, read the literature, surfed the internet. Saw the warnings. But figured the odds were in my favor" ... "I have unbearable pain in the right eye at night. So severe, I cannot sleep and must resort to NSAIDS, acetaminophen, and hydrating eye gels around 4am, every night"

- "The surgery was so unprofessional. the doctor was talking to his assistants the whole time like I wasn't even there" ... "its almost been a year and my eyesite is back to where it started but worse" ... "I went to see another eye doctor, she was shocked at the scarring on my eyes"

- "After the first 30 days, my eyesight started getting worse" ... "doctor who checked my eyes this time seemed young and inexperienced" ... "I didn't get the surgery so that I would have to wear contacts again"

- "got many floters in one month" ... "Those eye doctors couldn't wait to earn big money, so they started this surgery without thorough research"

Sources:
http://www.fdanewsalert.com/id580.html
http://blogs.consumerreports.org/health/2009/07/lasik-eye-surgery-lasik-survey-getting-the-best-price-for-lasik-survey.html
http://www.realself.com/Lasik/reviews?sort=most_discussed

Photorefractive Keratectomy Surgery

2009-08-06T04:35:00.000-07:00

Definition

Photorefractive keratectomy is a refractive medical operation that does not involve the use of tools in the human body whereby the doctor uses an excimer (a stable atomic pair dimer in which one of the two bound atoms is in a higher energy state) laser to reconstruct the cornea by taking away the epithelium, the jelly-like exterior layer of the cornea.

Purpose

Although PRK decreases nearsightedness (myopia), farsightedness (hyperopia), and astigmatism (blurred vision), this surgery can best take care of myopia. People who have undergone PRK usually do it for many different reasons. A most common reason would be that people do not want to wear spectacles because they want to appear handsome or beautiful. Others who take part in lots of sports or physical training may find spectacles a great hindrance. Moreover, contact lenses often dry up, leaving people with blurred vision.

Process

The whole process is approximately 10 minutes. Directly ahead of the operation, the ophthalmologist will execute a refraction to ensure the refractive alteration the surgeon will instruct the excimer laser is right. Anesthetic drops will be used to numb the eye and disallow pain when the operation starts. After the eye drops are applied, the surgeon places a speculum in the eye to keep the eyelids apart and disallow movement. The patient stares at the twinkling light of a laser microscope and must keep his or her gaze steady on that light, staying motionless at the same time. The surgeon rechecks the laser co-ordinates to ensure they are right for the refractive mistake. When everything is in position, the eye surgeon takes away the epithelium with a sponge, mechanical blade, or the excimer laser. With the epithelium totally taken away, the surgeon will start reconstructing the cornea. Once the process is done, the surgeon puts a bandage contact lens on the treated eye to protect it and allow the healing process to take place; it also eases some of the pain of the exposed cornea. The surgeon will also dispense anti-inflammatory and antibiotic eye drops to stop infection and reduce pain.

Risks

Patients should have a complete eye evaluation and medical history taken before surgery. Soft contact lens wearers should stop wearing their lenses at least one week before the initial exam. Gas-permeable lens wearers should not wear their lenses from three weeks to a month before the exam. Contact lens wear alters the cornea's shape, which should be allowed to return to its natural shape before the exam. Patients should also disclose current medications. Allergy medications and birth control pills have been known to cause haze after surgery. Physicians will want to examine the potential risks involved with these medications. Patients who have these conditions/history should not have the procedure, including:

pregnant women or women who are breastfeeding
patients with very small or very large refractive errors
patients with scarred corneas or macular disease
people with autoimmune diseases
diabetics
glaucoma patients
patients with persistent blepharitis

Physicians will perform a baseline eye evaluation, including a manifest and cycloplegic refraction, measurement of intraocular pressure (to determine if the patient has glaucoma), slit-lamp biomicroscopy, tear film evaluation, corneal topography, evaluation of corneal thickness, dilated fundus examination, and measurement of scotopic pupil size. If the patient is an appropriate candidate, he or she must sign an informed consent form that states he or she is aware of possible complications and outcomes of the procedure.

PRK patients may experience glare, vision fluctuation, development of irregular astigmatism, vision distortion (even with corrective lenses), glaucoma, loss of best visual acuity, and, though extremely rare, total vision loss. A more common side effect is long-term haze. Some patients who have aggressive healing processes can form corneal scars that can cause haze. With proper screening for this condition and with the use of eye drops, this risk can be lessened. Complications associated with LASIK, such as photophobia, haloes, and dry eye, are not as common with PRK. However, the patient may be under-corrected or overcorrected, and enhancements might be needed to attain the best visual acuity.

Sources:

http://www.surgeryencyclopedia.com/Pa-St/Photorefractive-Keratectomy-PRK.html

Automated Lamellar Keratoplasty

2009-08-05T08:36:00.001-07:00

Diagnosis

The patient is diagnosed with severe levels of myopia or mild levels of hyperopia (farsightedness). To provide the custom treatment for the severity of the patient’s eye(s), the doctor will evaluate the medical history including glasses’ prescription, if any, and measure the corneal thickness, refraction and pupil dilation of the eye(s). This is required to determine the shape to cut which will restore perfect vision for the eye(s). Also, a coordinator will discuss with the patient about what to expect after the surgery.

Preparation for doctors

To begin the operation, the doctors have to prepare a device called a microkeratome which removes a thin disc of the cornea. More importantly, doctors have to calculate the shape to cut according to the patient’s eye(s). Other things include anaesthesia and the operation room itself.

Process #1

The eye is anesthetised and a ring is fixed to it in order to prevent if properly positioned and flat.

The microkeratome is used to incompletely cut a thin flap of cornea so as to expose the layer of tissue below. Then, the microkeratome is used again to carve the right shape in the cornea so as to change the shape of the eye lens. The flap is then replaced for it to heal. However, if the patient is hyperopic, the flap is replaced back without removing anything. This is because the cornea stiffens during recovery. This operation usually takes less than an hour.

Recovery and results

Just 24 hours after the operation, patients are almost healed and able to see clearly. Besides, patients feel very comfortable after the surgery although it may take months to regain vision stability. The results may sometimes be unpredictable, but ideally, the patient will have perfect vision after the surgery.

Possible Side-effects

Glare

Inability to wear contacts, sometimes permanently

Infection

Corneal scarring

Overcorrection or under-correction

Inflammation

Due to presence of more predictable and efficient types of operations, this type of surgery is not routinely performed anymore.

Sources

http://en.wikipedia.org/wiki/Automated_lamellar_keratoplasty

http://www.webmd.com/eye-health/keratoplasty-eye-surgery-alk-myopia-hyperopia

http://www.the-lasik-directory.com/alk.html

http://www.eyecare-information-service.org.uk/lasereyesurgery/alk.html

http://blogs.consumerreports.org/health/2009/07/lasik-eye-surgery-lasik-survey-getting-the-best-price-for-lasik-survey.html

Updated Mindmap with references

2009-07-21T02:53:00.000-07:00

Edited Research Question

2009-07-21T02:03:00.000-07:00

Problem Statement: How accurate risks of surgeries shown by LASIK and how effectively are they conveyed?

We thought that it would be good to research on the dangers of Lasik as not many people know the procedure well since the information provided by LASIK might be limited or inaccurate as they would want to cloud some of the information as not to scare of their patients. We would also need to find out how strongly does LASIK enforce their patients awareness and knowledge in what they themselves are going through and the risks they are taking.

What we intend to do:

We intend to find out about how the Lasik treatment will affect the person’s eyes and even health and compare it with the information provided by LASIK, hence, changing the information in their advertisements or brochures, which are supposed to educate the public, so that the patients have a clearer view of what they are going through. We would also need to find out how knowledgable patients really are when they accept these surgeries so as to know LASIK's enforcement on the patients' awareness.

Research Question

2009-07-14T04:18:00.001-07:00

Reflection
-- How did the group come up with the problem statement?
-- What did you do well? e.g. difficulties faced and were overcome, how you overcome them
-- What did you not do well? e.g. difficulties that have yet to overcome due to some barriers
-- What you intend to do?

Problem Statement: What are the risks of lasik?

We thought that it would be good to research on the dangers of Lasik as not many people know the procedure well.

We had problems trying to create the mindmap as it needed a lot of details thus we just had to split the work up. However, we were able to collate everything and the mindmap was understandable.

We think our group had a hazy out view of the whole project because there are plenty of risks involved in Lasik.

We intend to find out about how the Lasik treatment will affect the person’s eyes and even health and whether a Lasik procedure is worth it, both to the person’s well-being and money.

PBL Mindmap

2009-07-12T03:00:00.001-07:00