Professor Zhao Jialiang Professor Chu Renyuan, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences Professor Zhou Yuehua, Affiliated Eye, Ear, Nose and Throat Hospital of Fudan University Professor Qu Jia, Peking Tongren Hospital Professor Ye Lian, Wenzhou Medical College College College of Optometry Professor Zhou Xingtao, Affiliated Huashan Hospital, Fudan University Associate Professor Wang Qinmei, Affiliated Eye, Ear, Nose and Throat Hospital of Fudan University Professor Wenzhou Prof. Wang Zheng, College of Optometry, Medical College of China Prof. Wang Zheng, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, China
Executive/You Huang
Expert Support
Ophthalmology, Peking Union Medical College, Chinese Academy of Medical Sciences (PUMC), Beijing
Professor Zhao Jialiang
Ophthalmology, Affiliated Hospital of Ophthalmology and Otorhinolaryngology of Fudan University, Fudan University, Shanghai, China
Prof. Chu Renyuan, Associate Professor Zhou Xingtao, Huashan Hospital of Fudan University, Beijing
Professor Zhou Yuehua
Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, China
Professor Wang Zheng
College of Optometry, Wenzhou Medical College
Professor Qu Jia Prof. Wang Qinmei
Department of Ophthalmology, Huashan Hospital, Fudan University
Professor Ye Lian
December 6, 2004 The Sunday Times published an article entitled "Eye surgery too dangerous for the NHS", which stated that the safety of excimer laser in-situ keratomileusis (LASIK) was of concern in view of the fact that a number of patients had recently experienced loss of visual acuity, weakening of the cornea's strength, infections, and retinal detachment after treatment of nearsightedness or farsightedness with LASIK, which was a safety concern, and that the UK government's healthcare regulator had blocked the use of LASIK on the NHS from performing excimer laser surgery. The article also points out that the failure rate of eye laser surgery is about 10 percent, not the 0.1 percent that is claimed in most advertisements. The National Institute for Clinical Excellence (NICE) also argued that LASIK should not be used as a clinical routine in the UK, and should not be included in the NHS without further research and approval.
The article was reproduced by a number of domestic media, about the "UK called off excimer laser surgery" said the spread, LASIK surgery failure rate of up to 10% of the data alarming, which triggered the "excimer laser surgery in the end safe or unsafe! The question of "whether excimer laser surgery is safe or not" has also left many people who wish to treat myopia through surgery at a loss.
In order to allow readers to objectively view the so-called "UK called off excimer laser surgery" incident, a more in-depth understanding of excimer laser surgery, in order to be more safe to undergo surgery, to obtain better surgical results, this magazine invited domestic ophthalmology authority of the incident in the United Kingdom, the status of the development of excimer laser surgery in China and how to ensure the safety of surgery and other issues to express their views. The publication invited domestic ophthalmology authorities to express their views on the British incident, the development status of domestic excimer laser surgery and how to ensure the safety of surgery.
Disclosure
Currently, millions of people in China have realized their dream of removing glasses and regaining clear vision through laser surgery. At the same time, more people are preparing to undergo the surgery. The disclosure of the "British incident" is undoubtedly a big blow to these people. So, is the UK's claim scientific or not? What is the reaction of other Western countries? Is the failure rate of laser surgery that high? What is the situation in our country? And listen to what the experts say.
Question 1: Is the failure rate really as high as 10%?
Chu Renyuan, Zhou Xingtao: a correct view of the "10% failure rate"
If the normal corneal tissue lesions, such as corneal infection, perforation, etc., after laser surgery, is recognized as a complication, the rate is usually less than 1%. Disagreements may arise primarily over the definition of "failure" or "unsuccessful" due to the limitations of the preoperative lens itself. Most people consider a 1.0 visual acuity to be a complete success. This is not the case. Visual acuity is important, but the quality of vision is even more important. People with poor visual quality after surgery, although the visual acuity reaches 1.0, but there are blurred edges of vision, night vision loss and other problems, and in serious cases, it will also affect daily life. Some statistics show that the percentage of people whose visual quality after excimer laser surgery is not up to the level of wearing glasses is usually more than 20% in high myopia. British statistics on the failure rate of surgery, if you include the postoperative aberration increase (the vast majority of cases of laser surgery after the aberration is increased), the visual quality of the decline in the problem, then 10 percent of the failure rate is not high.
Wang Zheng: Report exaggerates problems with LASIK
In 2004, the Institute for Clinical Excellence in the United Kingdom was asked to evaluate the effectiveness and safety of LASIK surgery, and on December 15, 2004, it issued Guidelines on LASIK Surgery for the Treatment of Refractive Error. Prior to the official publication of this document, an article entitled "Eye surgery too dangerous for the NHS" was published in the Sunday Times on December 6 and reprinted in several media outlets, causing shockwaves in the United Kingdom and around the world. Ophthalmologists, healthcare organizations and patients from various countries have expressed their opinions, with the vast majority believing that the British media's coverage of the matter was sloppy and exaggerated the problems with LASIK surgery, and that many of the comments and speculations were wrong.
Some UK ophthalmologists believe the literature cited by NICE is too dated, ignoring the advances in LASIK surgery in recent years and the emergence of new techniques such as wavefront-guided surgery. The Refractive Surgery Quality Assurance Council, a U.S. nonprofit organization that represents patients' interests, also issued a statement questioning reports in the British media that the failure rate for LASIK surgery is as high as 10 percent. The executive director of the organization said, "We are an organization that represents the interests of patients, and if the LASIK failure rate were really that high, we would be the first to point it out." According to statistics, about 1.2 million people underwent LASIK surgery in the US in 2004, compared to 100,000 in the UK. The incidence of LASIK complications in the US is about 3%, with less than 0.5% of those serious complications requiring surgical management. Many recent studies have also shown that the incidence of serious LASIK complications is under 0.5% or even 0.1%.
Qu Jia and Wang Qinmei: Failure rate is not scientific
First of all, it is important to clarify the correct meaning of "failure rate," which is not a strictly medical term. Generally speaking, the incidence of "complications" is used to illustrate the safety of surgery. It is not scientific or rigorous to use the word "failure rate" to describe safety. Take a very simple example: a patient who finds that the quality of vision has deteriorated after laser surgery can be said to have had a "surgical failure", while another patient who suffers severe visual impairment after laser surgery can also be called a "surgical failure", but the difference between the two is very large. But the difference between the two is huge.
After checking the original article "Eye surgery too dangerous for NHS" published in the Sunday Times, we found that the article was mainly caused by the fact that Boots, a British pharmaceutical company, was forced to close down nine excimer laser centers in the UK because of the blurring of vision and damage to vision after performing excimer laser surgeries on nearsighted patients, thus triggering a public outcry against excimer laser treatments. sparked public concern about the safety of excimer laser treatment for myopia. In fact, the problems that occurred in only one company do not represent the level and real situation of excimer laser surgery in the world. The 10 percent failure rate referred to in the article, quoted in the journal Ophthalmology, literally refers to the failure rate of eye surgery, not just excimer laser surgery.
Zhou Yuehua: Failure rate so high that it is not credible
If the failure rate of excimer laser surgery is really as high as 10 percent, then the procedure is well worth "stopping". Imagine, if the failure rate of the operation is so high, 10 people to do the operation, one person is a failure, then the operation will bring pain and regret to how many people!
Question two: does not approve the inclusion of the NHS is equal to "call off the operation"?
Zhou Yuehua: conceptual error
Not approved to enter the National Health Service does not mean that excimer laser surgery in the United Kingdom will not be done, banned, but only not approved to enter the equivalent of the domestic "medical insurance" only.
Wang Zheng: "call it off" is groundless
Since 1990, the NHS has been offering LASIK surgery to patients who wear frames or contact lenses to correct unsatisfactory vision, about 800 people a year, accounting for 0.8 percent of the UK's LASIK surgeries. The NICE guideline document focuses on the question of whether LASIK can be used as a routine treatment for refractive error in the NHS in the same way as frames and contact lenses, so the requirements for its safety are very strict.
At the same time, since the NHS provides free healthcare, it is in line with international practice not to include LASIK as a routine treatment on the NHS.
Chu Renyuan, Zhou Xingtao: proceed with caution, not ban
The British report focuses on the more complications arising from excimer laser treatment of myopia, especially high myopia, and hopes that people will proceed with caution, rather than opposing it, not to mention banning it.
Question 3: Why are there so many serious problems with LASIK in Britain?
Zhou Yuehua: late start, technology is slightly inferior
There are two main reasons why there are so many problems with LASIK surgery in the United Kingdom: First, LASIK surgery in the United Kingdom started late, and so far it has been only three to five years, the technical level and proficiency of practitioners is not too high; second, in the United Kingdom, LASIK surgery is mostly done in some private clinics, public hospitals basically do not do it, private clinics do not do it, and private clinics do not do it. Secondly, in the UK, LASIK surgery is mostly performed in some private clinics, and public hospitals basically don't do it, and the medical level, hardware facilities, and ability to deal with emergencies in private clinics are relatively poor. At the same time, the United Kingdom has a relatively complete medical supervision system, once the problem is found, the administration will take the necessary measures to prevent the situation from becoming serious.
Question 4: What is the level of excimer laser surgery in China? Are there as many problems as in Britain?
Zhou Yuehua: the domestic situation is not optimistic
The excimer laser surgery has been carried out in China for more than 10 years, and thousands of myopic patients have benefited from it. What should be emphasized is that the problems encountered in the UK also exist in our country, and even the situation in some parts of the country is much more serious than in the UK. As one of the early hospitals in China to carry out excimer laser surgery, Peking Tongren Hospital often encounters patients from all over the country who ask for "rework" because of failed surgeries, a small number of them are relatively satisfied with their vision after the second surgery, but others are not so lucky, with deteriorating vision, blindness and the need for corneal transplants. corneal transplants, all of them.
Currently, China's excimer laser surgery is facing the biggest problems are three: First, the medical level (including hardware, software) gap is too large, leading directly to the success rate of the operation is far from each other, for example, in some of the regular hospitals, the success rate of the operation can reach more than 99%, while in some small hospitals, the operation's success rate of only 70%, or even lower; Second, the lack of regulation of the use of surgical equipment, many hospitals to attract patients at low cost, and the use of surgical equipment. Many hospitals to attract patients with low prices, but do not know that this low price is a cheap, low performance machines, surgical instruments repeatedly used in exchange for; Third, many medical institutions to excimer laser surgery as a profit-making tool, false advertising everywhere, patients often blindly because of the advertisements and propaganda.
Wang Zheng: lack of regulation of medical advertising, medical quality is difficult to guarantee
China's various regions, the development of medical institutions at all levels is not balanced, the relevant medical management training, supervision system is not perfect, resulting in the technical level of the doctor and the medical effect of the great differences, and the domestic refractive surgery market vicious competition, medical advertising regulation is not effective, the competition to kill the phenomenon of serious, medical quality is difficult to guarantee. Another major evil consequence is that medical investment is getting less and less, and advanced equipment and technology are difficult to be applied in a timely manner, leading to slow or even stagnant development of refractive surgery in China. In the long run, it is very unfavorable to patients.
Qu Jia and Wang Qinmei: overall synchronization with the world's advanced level, but still need to be cautious
China introduced the excimer laser to carry out PRK surgery in 1993, followed by LASIK surgery. Now, there are more than 700 excimer laser surgery centers of different sizes in China. Last year, China *** carried out about 500,000 cases of excimer laser surgery. Overall, the level of excimer laser surgery in China has kept pace with the world's advanced level and is in rapid and steady development. However, there is a big gap between the overall medical level in China, and some medical institutions with low level and poor conditions are also carrying out excimer laser surgeries. Failed cases, the vast majority of which occur there, are caused by their inexperienced surgeons, non-standardized operation procedures, backward equipments (or even the introduction of foreign obsolete equipments), and low-priced competitions, which directly lead to the decline of medical quality and the proliferation of medical disputes.
Question 5: Excimer laser surgery in the end safe, effective?
Zhao Jialiang: There are advantages and risks
Excimer laser surgery has been carried out for more than 20 years, and now it is widely practiced around the world, with thousands of people regaining clear vision through the surgery. From this point alone, it is clear that the excimer laser has advantages in the treatment of myopia. At the same time, excimer laser surgery, like any other surgery, carries certain risks. What's more, since the procedure involves cutting into the normal cornea, it is a kind of "icing on the cake" surgery that is not mandatory, so patients are advised to have a more comprehensive and correct understanding of the risks of the procedure.
Wang Zheng: The safest and most effective refractive surgery to date
LASIK is a highly elective procedure, and both doctors and patients should be well aware of the risks of the procedure itself. Although many years of clinical practice and millions of clinical results around the world have proved that LASIK is the safest and most effective refractive surgery to date, it is important to remind that the "safety and effectiveness" of LASIK is based on correct surgical design, skillful surgical techniques, high-quality surgical equipment, and comprehensive postoperative follow-up. The LASIK surgery is a very effective and safe procedure, as it is based on correct surgical design, skillful surgical techniques, high-quality surgical equipment and perfect post-surgical follow-ups.
Zhou Yuehua: choosing the right hospital and the right doctor is the first condition to ensure safety
As long as you choose the right hospital and the right doctor, excimer laser surgery is safe. In fact, wearing contact lenses is not safer than laser surgery. Taking Beijing Tongren Hospital as an example, there is hardly any safety hazard after excimer laser surgery, while contact lens wearers have dozens of visits every year due to infection.
Chu Renyuan and Zhou Xingtao: six necessary conditions to ensure the quality of surgery
With the continuous updating of surgical equipment and examination instruments, and the continuous improvement of surgical methods and techniques, the safety of excimer laser surgery has been greatly improved compared with the past. In short, to ensure the quality of surgery, the following six conditions must be met: ① comprehensive and correct preoperative examination; ② appropriate surgical design; ③ skillful surgeon; ④ perfect hardware facilities; ⑤ proper cooperation of the patient; ⑥ standardized postoperative medication and follow-up.
Qu Jia and Wang Qinmei: We need to standardize surgical operation and strengthen supervision
The ideal refractive surgery should achieve the following goals: safe and effective; no degradation of visual quality; accurate and predictable; stable results; keeping the eye structure intact; painless surgery; mild postoperative reaction; fast recovery; reversible and adjustable.
The domestic emergence of some hospitals do not talk about the conditions and level, arbitrarily carry out excimer laser surgery, seriously reduce the safety of the operation, intensifying the contradiction between doctors and patients this phenomenon, the relevant departments should adopt the principle of "two hands". Medical, should develop a unified surgical standards, raise the threshold of surgical qualifications, standardize surgical operations; supervision, the relevant government departments should take effective measures as soon as possible to strengthen the supervision, to carry out excimer laser surgery hospitals, doctors and medical equipment for effective management.
Reporter's comments:
From the insightful analysis of the ophthalmology experts, we can clearly draw the following conclusions:
1. The statement about "the UK called a halt to excimer laser surgery" is a pure misunderstanding. "Not approved for inclusion in the NHS" does not mean that excimer laser surgery is banned in the UK, but only means that it is not included in the scope of free medical care, just as LASIK surgery is not covered by our health insurance.
2. Concerns about the safety of laser surgery are not without merit, although the failure rate of up to 10% is not conclusive.
3. Excimer laser surgery is an "icing on the cake", not a necessity. Like any other surgery, it carries certain risks and there may be some complications after the surgery, which should be carefully considered by the patient.
4. LASIK is currently recognized as the safest and most effective refractive surgery in the world, but the success of the surgery is closely related to the design of the surgery, the level of skill of the surgeon, and the quality of the laser equipment.
5. Although the domestic surgical level has been synchronized with the world, the difference in medical level is huge. It is recommended that patients keep a clear head, do not follow the advertisement, or be confused by the "low price", should choose the quality of hospitals and doctors with good technology to do the surgery.
Analysis
In order to safely undergo the surgery and get the best surgical results, it is very necessary to have an in-depth understanding of the relevant knowledge of excimer laser, including the type of surgery, surgical indications, surgical risks, surgical procedures, surgical complications and so on.
Removing glasses doesn't change the nature of myopia
Professor Zhao Jialiang of the Department of Ophthalmology, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences
Every patient who has undergone or is about to undergo excimer laser surgery should make it clear that the surgery can only help you remove your glasses, and it can't change the nature of your myopia. Take a simple example: if you are 1000 degrees myopic before the surgery, and your naked eye vision reaches 1.0 after the surgery, and you don't need to wear glasses, even though you look like a normal person on the surface, your intraocular structure and retina are still in the original state of high myopia, and all the complications that may occur in high myopia, such as glaucoma, retinal detachment, etc., are likely to occur, so don't neglect the protection of your eyes because you don't need to wear glasses. protection.
Excimer laser myopia surgery family inventory
Ophthalmology Department of Eye, Ear, Nose and Throat Hospital of Fudan University Xiaoying Wang (Dr.
Excimer laser originated in the early 1970's, which is a combination of inert gases and halogen molecules of the dimer, the wavelength of the wavelength of the ultraviolet spectrum in the ultraviolet spectrum, is a kind of invisible light. Its most important feature is that the energy it releases can break the molecular bonds of corneal cells very precisely, vaporizing the corneal tissue without the slightest thermal damage to nearby tissues. There are four types of excimer laser surgeries*** currently being performed, as shown in the table below.
Comparison Table of Excimer Laser Procedures
Surgical Procedures
PRK
LASIK
LASEK
Epi-LASIK
Birth Date
1983
1990
1999
< p>2002Procedure
The corneal epithelium is first removed, then cut with an excimer laser to correct myopia, and the corneal epithelium regenerates and recovers after a few days
The corneal flap is first made on the cornea with a knife, and then the flap is lifted, and cut with a laser, and finally the flap is reset
The flap is made with 20% ethanol, without a knife .
The corneal epithelial knife is used instead of ethanol to make the corneal flap, which is much thinner than LASIK
Advantages
Simple surgical procedure, good safety, good effect on low and intermediate myopia
Wide range of myopia treatment degrees, no postoperative pain, rapid recovery of visual acuity
Good safety, less irritation than PRK, corneal haze cloudiness is mild or absent; people with thinner corneas are more likely to have a corneal flap. Thin corneas can also be operated on
Good safety, less irritation, mild or no corneal haze; thin corneas can also be operated on
Disadvantages
Postoperative pain for a few days, slower recovery of vision, subcorneal haze and postoperative hormonal IOP may occur in high myopia levels
Corneal flap-related complications (e.g., flap displacement, flap loss, etc.), thin corneas can also be operated on
Corneal flap-related complications (e.g., flap displacement, flap loss, etc.), and thin corneas can have a rapid recovery from myopia levels. The corneal flap-related complications (such as flap dislocation, flap loss, etc.) and thin corneas cannot be operated
Higher surgical skills, slower visual recovery than LASIK, high degree of corneal haze and postoperative hormonal intraocular pressure may occur
Surgical techniques, slower visual recovery than LASIK, high degree of corneal haze and postoperative hormonal intraocular pressure may occur
Best Indications
100 to 500 degrees of myopia, less than 600 degrees of hyperopia
100 to 1200 degrees of myopia, less than 600 degrees of hyperopia, the cornea thickness of more than 480 microns
100 to 500 degrees of myopia, less than 600 degrees of hyperopia, the cornea thickness of less than 480 microns can not be done LASIK
Or the cornea thickness of 480 microns or more.
Those who are allergic to ethanol and are not suitable for LASIK, the rest are the same as LASEK
Surgical cost
Low
Higher
Higher
Higher
Higher
Surgeons are more expensive than those who are allergic to ethanol. modality is perfect, and the only way to choose the most appropriate is to choose the best.
The knife in the normal cornea, there are risks
Fudan University Huashan Hospital Ophthalmology Ye Lian (Professor)
Operative risk
Intraoperative risk
Intraoperative complications occur mainly in the process of flap making, at this time, if the patient to cooperate with the doctor's operation or the operation of the instrument problems, it will lead to such as corneal flap is too thin, the flap of the corneal flap, the flap of the corneal flap is free, the flap of the corneal flap is not complete, The corneal flap deviation or even the corneal flap cut through, the corneal flap broken and so on.
Second, the early postoperative risk
Excimer laser surgery can be infected in the early postoperative period, overcorrection or undercorrection, laser cutting eccentricity, dry eyes, visual fatigue and other complications.PRK and LASEK due to epithelial loss or incomplete, the recovery is slower, and there is pain, and will occur in the cornea foggy cloudy and other problems.LASIK surgery, although the postoperative recovery is fast, painless, rarely the above problems, medication time is also very short, and the time is also very short. Although LASIK has a quick and painless recovery and few of these problems, and the medication time is short, complications such as laminar keratitis, interlaminar foreign bodies, and epithelial implantation are still possible. In addition, excimer laser surgery also affects the quality of vision, such as the production of night myopia, glare, etc. LASIK surgery if the corneal flap thickness is not uniform, there may be double vision.
Three, postoperative long-term risks
High, ultra-high myopia patients with excimer laser surgery is prone to vision regression problems, and there is the possibility of corneal bulging due to the residual corneal thickness of the thin, the corneal flap may not be able to heal completely after LASIK, trauma or other eye surgery, flap displacement or loss, which can occur two years after surgery or more, patients should be carefully considered before LASIK. Patients should exercise careful discretion before surgery.
The risks of surgery
Qu Jia, professor at the Optometry Hospital of Wenzhou Medical College
Most of the "patients" who undergo excimer laser surgery are not patients with "eye disease" as the term is commonly used, but rather "healthy" patients with refractive error. They are "healthy" people with refractive errors. These people often choose to undergo the surgery with the intention of meeting the medical examination requirements of their employers, or hoping to remove their glasses for life and improve their quality of life, or for the sake of better aesthetics and convenience. They have high expectations of the surgery and will demand more from the surgery in terms of safety and effectiveness. It is not unusual for complications of such surgeries to be a major concern.
The complications of excimer laser surgery can be categorized into two main groups: one is irreversible damage affecting the health of the eye, such as infection and secondary cone cornea. At present, such complications rarely occur. Since 1995, when the Affiliated Optometry Hospital of Wenzhou Medical College started the excimer myopia laser surgery, the complication rate is less than 0.1%, and among the 0.1%, there is a considerable percentage of problems caused by the visual quality. The second type of complication is about the evaluation of visual quality aspects, such as contrast sensitivity, glare and other functional visual indicators. In some patients, the corrected visual acuity can reach the expected goal after surgery, but the visual quality does not reach the expected result, resulting in postoperative dissatisfaction, and this aspect needs further research and exploration.
Straight to the biggest disadvantage of excimer laser surgery ---- visual quality decline
Yu Zhiqiang (PhD), Excimer Laser Center, Eye, Ear, Nose and Throat Hospital, Fudan University, Foshan, China
In recent years, excimer laser In recent years, excimer laser surgery has taken off and blossomed all over the country, with all kinds of advertisements spreading all over the place, boasting excimer laser to be godly and omnipotent. In fact, any surgery has its advantages and disadvantages, the perfect surgery does not exist in the world.
Regardless of the obvious problems that may occur in excimer laser surgery, such as corneal flap failure and eccentric laser cutting, even if a seemingly successful surgery - the patient's naked eye vision reaches 1.0, or even 1.5, there are also its flaws. -decreased visual quality.
Visual quality is a higher-level concept than visual acuity, which requires not only normal vision of 1.0 or higher, but also clarity, comfort and stability. In addition to the refractive error being orthoptic, it also involves factors such as aberration, contrast sensitivity, night vision and tear film stability. The current excimer laser technology can only improve the naked eye vision, but can not improve the quality of vision, on the contrary, the surgery will also lead to a decline in the quality of vision.
I, aberration increase
Excimer laser surgery is through the laser to remove part of the corneal tissue, change the curvature of the cornea to correct the refractive error. However, while the laser changes the corneal curvature, it also changes the aberration of the whole eye system. The smaller the aberration, the clearer and more comfortable the vision. Although theoretically, postoperative aberration can become larger or smaller, the current human understanding and application of aberration is far from making it more perfect than the natural state, which means that postoperative aberration is increased in the vast majority of cases and affects the quality of vision.
Second, the contrast sensitivity decreases
Contrast sensitivity is also a measure of visual quality, some myopic patients after the operation of visual acuity of 1.0, but will feel that the color of the visual acuity table on the vision markers become lighter, not as sharp as the original so vivid and sharp, this is the performance of the decline in visual sensitivity. The decrease in contrast sensitivity is related to the degree of myopia before treatment and the optical cutting zone, the higher the original degree, the smaller the optical cutting zone, the more obvious the decrease in contrast sensitivity.
Three, night vision loss
Myopia patients with more than 300 degrees of myopia in the early days after excimer laser surgery usually complain that the night vision is not as good as during the day, or encounter rainy days with vision loss phenomenon. Especially when driving at night, when the opposite side of the car on the high beam, the driver will feel in front of the eyes of a white, can not see anything. As a matter of fact, this is one of the difficulties that excimer laser surgery has not yet overcome, and the main reason is the decrease of contrast sensitivity and the increase of aberration as mentioned earlier. Therefore, it is recommended that friends with medium and high myopia who need to drive at night should be cautious when considering excimer laser surgery.
Four, tear film stability decreased
Normal human cornea surface has a layer of tear film, it is also an important part of the refractive system of the human eye. Once the tear film is destroyed, the front surface of the eye loses its integrity, which on the one hand will cause dry eyes, foreign body sensation, visual fatigue and other problems, and on the other hand will also make the refractive system of the eye affected, and the light is scattered irregularly when passing through the tear film, which will also cause the aberration to increase, and the quality of vision to decrease.
LASIK surgery cuts off the nerve endings in the superficial corneal layer during the creation of the flap, resulting in decreased corneal sensitivity and malnutrition, which affects the stability of the tear film. Although the stability of the tear film is gradually restored as the corneal nerve endings are repaired, this often takes six months or even longer.
Hope: "improve the quality of vision" has been included in the research topic
Recently, in Wenzhou Medical College under the leadership of the Peking Union Medical College, the Peking Union Medical College Hospital, Guangzhou Zhongshan Ophthalmology Center, Fudan University Eye, ENT Hospital and other more than 10 medical units*** with the participation of the Ministry of Science and Technology to carry out the fifteen research topics Research on "Improving the Safety and Effectiveness of Refractive Surgery": On the premise of standardizing and regulating excimer laser surgery to minimize the incidence of irreversible damage to the eye, further exploring the influence of visual quality factors; in line with the principles of safety, efficacy, accuracy, stability, and minimal damage, we will achieve the same goal of achieving the highest quality of vision on the basis of the principles of safety, efficacy, accuracy, stability, and minimal damage. The same optic clarity, comfort, and durability are achieved based on the principles of safety, efficacy, accuracy, stability, and minimal damage.
Guidance
Once you have decided to have the surgery, how to choose the right hospital, the right doctor, and how to ensure the quality of the surgery has become the primary problem, and it is recommended that you listen to the expert's advice first.
Laser surgery is a systematic project
Huashan Hospital of Fudan University, Department of Ophthalmology, Professor Ye Lian
Ophthalmology, Eye, Ear, Nose and Throat Hospital of Fudan University, Dr. Zhou Hao
Exacerbation laser surgery is not a simple programmed surgery, and it is not only relying on an experienced surgeon and a state-of-the-art laser surgical equipment to achieve the ideal surgical results. It is a complex systematic project. It is a complex systematic project, preoperative examination, surgical design, intraoperative operation, patient cooperation, postoperative medication and care, each link is closely related to the surgical effect.
Preoperative examination should be correct
Detailed preoperative examination is indispensable, which includes visual acuity examination, refractive examination, anterior segment of the eye and fundus examination, intraocular pressure examination, corneal thickening, corneal topography examination, wavefront aberrometry examination, contrast sensitivity, tear film rupture time and tear secretion test, etc. The following three examinations are very important, which directly affect the outcome of the surgery. The following three examinations are very important and directly related to the success or failure of the surgery.
Medical Optometry The theory of medical optometry was put forward by Prof. Chu Renyuan in 2000, and has been widely adopted. The difference between medical optometry and general optometry is that it emphasizes the improvement of the visual function of both eyes. In addition to checking the refractive error of each eye accurately, it is also necessary to check the balance of both eyes, the position of the eyes, the adjusting power, and the function of monovision of both eyes, etc. The medical optometry method is used to perform the surgery. The application of medical optometry for the design of the amount of surgery can ensure a high quality of vision after surgery.
Corneal topography and anterior segment analysis system examination Exclusion of preclinical cone cornea, patients with a tendency of cone cornea should be followed up for a long period of time, and should not be operated hastily, so as not to cause corneal perforation artificially.
Preoperative preparation should be perfect
Antibiotic ophthalmic solution ordered for a period of time before surgery can reduce the bacteria in the conjunctival sac and prevent the occurrence of postoperative infection. However, the time should not be too long, usually 3 to 5 days is appropriate, so as to avoid the preservatives in the eye drops damage the corneal epithelium.
The cleaning of the conjunctival sac on the day before surgery is also very important. If the rinsing is not sufficient, bacteria and secretions remain in the conjunctival sac, which can easily lead to the occurrence of postoperative infections, but if the rinsing is excessive and the concentration of antiseptic is too high, it can lead to the corneal epithelium loosening, and the risk of epithelial implantation and other risks occurring in the postoperative period is greatly increased.
Intraoperative operation should be standardized, the doctor-patient cooperation should be good
How the surgical effect, the design of the surgery and surgical operation is important. In addition, since the surgery is performed under surface anesthesia, if the patient does not cooperate well during the surgery and does not keep a close eye on the red light above the head as required by the surgeon, when the eyeball shifts more than what the machine can keep track of, this will lead to a decrease in the precision of the cutting and eccentric cutting, and in severe cases, it may lead to an interruption of the surgery. Therefore, patients should fully understand the surgical process before the operation and have some simple training to avoid being too nervous during the operation.
Postoperative follow-up should be adhered to
Post-operative follow-up after excimer laser surgery should be on time in order to closely observe the post-operative situation, evaluate the effect of the surgery, discover post-operative complications in time, and reasonably use medication under the guidance of the doctor. Generally speaking, postoperative routine antibiotic eye drops for 2 weeks, corticosteroid eye drops for 1 to 2 months. The next day after surgery, one week after surgery, one month, three months, six months should be regularly reviewed.