Myopia laser surgery revealed
Mr. Chen is a highly nearsighted patient, with over 900 degrees in both eyes, and with astigmatism. Because he has to wear thick and heavy deep glasses for a long time, Mr. Chen often feels discomfort and dizziness in his head. After hearing that laser treatment for myopia is very mature, Mr. Chen decided to go to Sun Yat-sen University Zhongshan Ophthalmic Center for excimer laser surgery. Soon after the surgery, he not only removed his glasses and returned to 1-2 vision in both eyes, but also no longer had the pain he used to have.
For many myopic friends, excimer laser surgery is no longer a stranger, but many people still have concerns.
Who isn't afraid of surgery on the eye? So how exactly does the laser "knife" in the eye? Professor Ge Jian, director of the Zhongshan Eye Center at Sun Yat-sen University, unraveled the mystery for us.
Laser surgery has been two generations
Excimer laser surgery (PRK for short) is the late 1980s began to be used in clinical applications. Zhongshan Ophthalmic Center of Sun Yat-sen University has successfully relieved more than 10,000 patients of their pain and worries since 1994 when the technology was launched. Excimer laser is a kind of "cold laser", it is a kind of excitation dimer laser, it is under the control of the computer, according to the refractive error that needs to be corrected, the corneal tissues are cut precisely, and the curvature of the cornea is changed, in order to achieve the purpose of correcting the eyesight. This is the basic principle of its surgery.
Excimer laser in-situ corneal resurfacing (LASIK for short) is one of the most advanced surgeries for myopia that has been developed in recent years, and is particularly suitable for high myopia. Currently, LASIK is also used in eye centers, which is to cut a "corneal cap" with a thickness of 0-16mm on the corneal surface, flip it over, then cut the corneal stroma with an excimer laser, and finally reset the "corneal cap" without sutures. No sutures are needed. Comparatively speaking, LASIK has more advantages than PRK: no obvious postoperative pain, faster vision recovery, less myopic regression, and fewer complications. In addition, LASIK is more effective for high myopia.
Success rate of 95%
At present, millions of people around the world have undergone excimer laser surgery, including myopia, astigmatism and hyperopia patients. The procedure takes only five minutes and has a 95 percent success rate. Four or five days after the surgery, the patient can resume basic normal eye use. However, it is important for patients to understand that this surgery does not treat the root cause of the refractive error, and therefore, postoperative visual acuity can be as good as or close to the preoperative visual acuity with glasses.
Due to the differences in machines or the experience and level of doctors, as well as the individual differences of the operators themselves, these factors will have a certain impact on the results of the surgery and may result in some complications, such as: corneal subepithelial haze clouding, corneal infections, induced astigmatism, nighttime glare, myopia or astigmatism regression, and so on. Therefore, Prof. Ge believes that choosing a regular hospital and a professional doctor is a must for patients.
Contributed by Zi Rong, Sun Yat-sen University Eye Center
Expert Q&A
What are the advantages of laser surgery?
There are six advantages of laser surgery for myopia: 1) Direct processing of the corneal surface. 2) No significant change in the mechanical strength of the cornea after the surgery. 3) Controlled by a computer, with a high degree of accuracy. 4) Short operation time. 5) Stable postoperative results. 6) Very few complications.
Who is suitable for laser surgery?
Any surgery has certain indications. Therefore, those who are considering laser surgery must undergo a comprehensive and rigorous examination by an ophthalmologist and need to meet the following conditions:
1. Age above 18 years old, with stable vision for more than two years.
2, no other diseases in the eye, have not had a larger eye surgery, such as glaucoma and retina surgery.
3. Those who wear contact lenses need to remove the lenses for 2 weeks and have no complications caused by contact lenses.
4, if you suffer from systemic or local serious infectious, systemic diseases, such as hepatitis, cardiovascular and cerebrovascular disease, or those who can not lie still, etc. are not suitable for such surgery.
Is laser surgery expensive?
Precision laser surgery (PRK) costs 3600 yuan for a single eye. Excimer laser in situ keratomileusis (LASIK) costs $5,000 for one eye
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Survey of safety issues in myopic laser surgery
Among those who undergo laser myopia, about 10 percent of patients need to have laser myopia surgery. About 10% of patients need to be "reworked". This figure is in line with the 10 percent failure rate published in the British journal Ophthalmology. In some hospitals with poor conditions, the success rate is even lower than 70%. So how safe is myopic excimer laser surgery?
Surgery like magic
At 2 p.m. on May 19, the refractive surgery department of the eye center of Peking Tongren Hospital. As usual, the 30-square-meter waiting room was crowded with patients. They are not ordinary eye patients, but a group of people who are medically known as refractive abnormalities, myopia, hyperopia or astigmatism - in which incoming light rays cannot be focused on the retina after being refracted by the cornea and crystals.
Here, excimer laser surgery will reshape the curvature of their corneas. Surgeons utilize an invisible light with wavelengths within the ultraviolet spectrum, which breaks the molecular bonds of corneal cells with great precision, vaporizing the corneal tissue without the slightest thermal damage to other tissues.
The operating room officially opened at 1 p.m. and did so until nearly 5 p.m. ended. This reporter saw a group of a dozen or so patients fishtail in and out of the room.
Despite the fact that the surgery required delicate skills like carving and polishing jade, the time was unimaginably short. From eye anesthesia to the end of the procedure, it takes only about five minutes. A nurse in the examining room said the total **** done this afternoon was 60 patients, "pretty much every day, or 20-30 on lesser days."
The walls of the waiting room are covered with "patient information". An article, "Currently Widely Performed Excimer Laser Surgery," describes that of the three procedures, excimer laser keratomileusis (PRK), excimer laser subepithelial keratomileusis (LASEK) and excimer laser in situ keratomileusis (LASIK), the one that has the widest scope of application and has been proven clinically to be the safest and most effective is LASIK.
Myopic patient from Hebei province Liu Xiaoming was in the last batch of the day. Two days ago, she rushed to Beijing Tongren Hospital from her hometown for a checkup, and after ruling out various contraindications to surgery, the doctor chose LASIK for her. The surgery cost her half a year's salary: 4,368 yuan for one eye, plus medication before and after the surgery, totaling **** around 9,500 yuan. And if it had been done in her hometown, she would have saved at least 3,000 yuan.
"I didn't dare to do it in a small hospital, and didn't they say recently that a lot of people who have had this surgery need to return to work?" She said, having just walked out of the operating room.
The next day, she found that she no longer needed to wear glasses when watching TV, and on the phone she was overjoyed, "It's really like magic, the doctor said that my vision can return to 1.2." but then she began to worry about the rumors.
Returns worrying
The news of the "return wave" first came from Shanghai, where radial keratotomy (RK) for nearsightedness was all the rage 15 years ago. But a few years later, many patients who underwent the procedure began to experience serious post-operative complications that caused their vision to regress. In the ophthalmology departments of some tertiary hospitals in Shanghai, the number of redo surgeries exceeds 600 in a year and is increasing at a rate of 20 percent a year, the media said.
In Beijing, the situation is equally bleak. It was recently reported that in some hospitals, "more than 1,000 people come for myopic laser surgery every month, while nearly 100 patients have 'rework' surgery at the same time," accounting for about 10% of the total number of patients.
The question that arises is obvious: although the RK technology that emerged 15 years ago has long been phased out due to its own shortcomings, and has been replaced by safer PRK, LASEK or LASIK, will these technologies follow in the footsteps of RK 15 years from now?
Similar warnings came internationally earlier in the year. On December 15 of last year, the UK's Institute for Clinical Excellence (NICE) published a report titled "Guidance on LASIK surgery for the treatment of refractive error," stating that the evidence is currently too scanty for widespread use to demonstrate the long-term safety of this surgical procedure, and that LASIK should not be used as a matter of routine clinical practice, and should not be included without further research and approval by the National Health Service (NHS).
In the report, NICE also tallied four pieces of clinical data and found that the incidence of post-operative problems related to corneal flaps such as flap dissolution, flap thinning, and flap deviation in position was about 4%, corneal burning sensation was 5%, and corneal tissue hyperplasia was about 2%.
The Sunday Times, which scooped the NICE report before it was published, also cited data from a paper in Ophthalmology by Dr. Peter S. Hersh of the New Jersey Medical School in the U.S., saying that the rate of second surgeries for this type of procedure was 1 in 10, not 1 in 1,000 as many advertisements claim. This report caused a shock worldwide, known as the "British call off excimer laser surgery incident".
The BBC followed up with a report from Bruce Campbell, chairman of NICE's Interventional Medicine Advisory Committee. In his interview, Prof. Campbell said that because vision correction can be addressed in such safe ways as wearing glasses or contact lenses, any treatment that poses a risk to the eye such as LASIK requires special attention.
Professor Campbell also warned that a small number of people had worse vision after undergoing LASIK and that eye specialists were looking at possible long-term side effects of the procedure.
The BBC's report, however, appeared more objective, and it also interviewed a number of clinicians who expressed general disappointment with the NICE report.
The eye surgery community in the U.S. similarly refuted the NICE report.
In 2004, 1.2 million laser eye surgeries were performed in the U.S., compared with 100,000 in the U.K. USAeyes sarcastically said on its Web site that if the rate of postoperative complications was really that high, it would have been the U.S. that would have noticed it first.
New findings?
Domestic media reports have once again raised public questions about excimer laser surgery. Since May 20, reporters have called NICE, the Vision Center at the Queen Victoria Hospital in the United Kingdom, and Dr. Hersh, the author of that paper in the journal Ophthalmology.
On May 26, Sheraz Daya, director of the Vision Center at the Queen Victoria Hospital in England. Dr. Sheraz Daya responded to questions from this newspaper by e-mail.
Reporter: What is the current clinical use of LASIK in the UK? Is the public accepting of the procedure?
Daya: L ASIK is not as popular in the UK as in other countries for several reasons, one being the conservative tendencies in the nature of the British people and their excessive concern for safety, and the other being that LASIK has not yet been introduced into the NHS (the equivalent of welfare healthcare - Ed.), and the British people are not used to spending their own money on healthcare.
Reporter: Is the long-term safety of this procedure guaranteed?
Daya: As long as the medical procedure is done correctly and the patient has no contraindications, there is no problem.
Reporter: But NICE has issued a warning.
Daya: The N ICE report was very poor and used old data. The inference that there is "little clinical practice in the UK" is incorrect because no new data has been included, and the NICE report does not adequately take into account the level of experience and practice in the UK in this area. I understand that the issue is being reassessed and we believe that the new conclusions should be different.
Reporter: Ophthalmology once published an article saying that the number of patients requiring a second operation was 1 in 10, what is that number at your treatment center?
Daia: The fact that a second treatment or revision is not considered a failure was a previous misconception. For several years, the secondary treatment rate for surgery at our own center was 2 percent, and with the introduction of femtosecond laser corneal laminar knife technology, that has now dropped further to 0.5 percent. Personally, I think it would be a shame if there is still 10 percent (failure rate) now, in 2005, and don't want that to happen in some good medical centers.
Reporter: What are your new thoughts on the technology now?
Daya: This technology is great, it's a technology that represents the way of the future, and the fact that we've been able to use it to change the lives of so many people is truly unforgettable!
Dr. Hersh also dismissed the misconception of 1/10 in his article, "The 10% I'm talking about is the secondary surgery rate, which is often used to achieve better vision results, and less than 1% of complications occur with LASIK now."
NICE, on the other hand, was extremely cautious. In several contacts, Woodward, the public **** relations manager, said that Professor Campbell was very much on the ball and was "looking at your interview questions and will respond later."
Problems remain
The Chinese ophthalmology community also organized a discussion two months ago after the NICE report was published. Zhao Jialiang, chairman of the Chinese Medical Association's branch of ophthalmology, said their main points were published in this year's 5th issue of the journal Popular Medicine and that "there is nothing new to add at this time."
They don't dispute that LASIK is now recognized worldwide as the safest and most effective refractive surgery, but "whether or not the surgery can be successful is closely related to the surgical design, the doctor's technical level, and how good or bad the laser equipment is." China introduced PRK in 1993, followed by LA SIK, the overall level of the world's advanced level of synchronization, "while some low level, poor conditions of the medical institutions are also carrying out excimer laser surgery, through the low price competition, this phenomenon is worrying."
Professor Zhao Jialiang estimated that more than 1 million patients have had this surgery in China in the past two years. He said, in fact, any surgery has risks, excimer laser surgery is the same, and it is just a kind of icing on the cake, it is not necessary to do, patients must be careful when choosing.
In the Tongren Hospital Eye Center Refractive Specialist's preoperative informed consent, it lists 21 possible serious consequences: in case of serious infection, the need for allogeneic cornea replacement, to the point of seriously affecting vision; the existence of overcorrection, undercorrection and refractive regression may be; pathologic myopia sometimes can not be determined before the operation, there is the possibility of postoperative development of the degree of degree higher than the original degree of; any degree of refractive patients have the possibility of a second surgery ......
"Although the possibility of surgical complications is very low, we have to tell every patient clearly that excimer laser surgery is also a minimally invasive surgery, which does not allow 100% of patients to achieve the expected results. results." Dr. Zhou Yuehua, deputy director of this specialty, said.
However, the doctor's own technical mastery, the reliability of the equipment and the standardized execution of medical procedures can also make a delicate procedure like LASIK perfect. According to data provided by Zhou Yuehua, Tongren Hospital has achieved more than 95 percent of the expected results in a single operation, and there have been no serious complications since 1993.
"A second surgery does not equal failure because each patient's own condition is different, and some surgeries are inherently designed to be completed in two stages, such as older patients with high myopia." He said.
But there are clearly holes in safety in some areas.In a four-day period from May 16-19, Tongren Hospital admitted three patients with serious LASIK complications. In their medical records, Zhou Yuehua wrote down the diagnosis of "corneal flap fragmentation" and "corneal flap dissolution", and the reason he was not willing to explain too much, "because in the position of Tongren, it is inconvenient to comment on other hospitals. "
Surgical failures like these are encountered hundreds of times a year at Tongren Hospital. Popular Medicine disclosed that "the success rate in some hospitals is below 70 percent, and the situation is not optimistic." A secret that is no longer a secret in the industry is that some hospitals buy second-hand equipment directly from foreign countries in order to cut costs
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When you are faced with the overwhelming advertisements of hospitals of all sizes, each saying how new and advanced their equipment is, and how clever their doctors are, you are really at a loss as to what to do when choosing. The first thing you need to do is to get your hands on a new one, and you'll be able to do that.
It is recommended to be sensible and calm in your consumer choices, and to be wary of the loudest fishmongers in the market, which are often stinky fish! Medical advertisements are often watered down and exaggerated!
1. Choose equipment to pay attention to the misunderstanding:
Excimer laser treatment of myopia common misunderstanding:
A. Laser instrument is actually the best generation?
Answer: There is no uniform "generation" in the world to mark the advanced nature of the laser! Do not blindly believe the advertisements and media publicity! Because there are one or two dozen manufacturers of excimer lasers in the world, each manufacturer has its own generation, only the first generation of the same manufacturer is comparable.
B. Is it true that the smaller the spot of the excimer laser, the better?
A: No. The spot is too small! The spot is too small, and when emitted at a certain frequency, it can interfere with the procedure by lengthening the duration of the procedure.
C. Is the newer the laser the better?
A: No, technology updates, especially medical updates often need time to verify the 5 to 10 years, the new machine needs to be familiar with the doctor to adapt, just like a new car to have a break-in period.
D. How do I know if a device is good or bad?
A. Data is the most persuasive!
The world's major excimer laser devices :
Wavelength Energy Scanning Time
Germany Imbert 193nm 120-180 gauss 6 sec Patent
Germany Iris 193 134 fiducials 22 sec
America Visions 193 140 fiducials 25
America Eagle Vision 193 130 fiducials 18
Japan Nidek 193 130-150 rotating 30
(Others omitted)
From the above table, it can be seen that the data of various lasers are basically the same, but the operation time is different! Since the shorter the time, the less time the cornea is exposed, the less dryness, the better the surgery, the better the patient cooperates on the operating table,
E. Follow the advertisement!
2. choose hospitals rather than choose doctors: as the saying goes: "the mountain is not high, there is God is spiritual, water is not deep, there is a dragon is famous", "worship Buddha to worship Buddha", and not blindly worship "big temple! The reason for this is that sometimes "small temples have small gods". Because sometimes "small temple God is big", but some "big temple God is small", rather than worshipping the "big temple" rather than seeking "real God The first is the "big temple", and the second is the "small temple".
In addition, the qualifications of the surgeon should not only depend on the degree, but also on the actual clinical experience of the surgeon in the field of myopia. How many cases of myopic laser surgery experience? How many years of myopic laser surgery history? Does the surgeon have enough experience? Is there a record of failure? What are the results for those who have had myopic surgery?
You can interview the surgeon directly or get a sidebar.
3. Whether the surgery is covered by insurance
In addition, the qualifications of the surgeon should not only be based on the degree, but also on the actual clinical experience of the surgeon, and the position the surgeon holds in the field of myopia. The actual doctor's experience in the field of myopia has been a great help to me in my endeavors," he said. "Not as good as seeking" true God "because sometimes" temple "small" God "big, sometimes" temple The reason is that sometimes the "temple" is small and sometimes the "temple" is big and sometimes the "temple" is small, so it is better to seek the true God rather than to worship the big temple.
★Komatsu blog original finishing. Reprinted with permission ★
The principle of laser myopia surgery is to use excimer laser, under computer control, to repair the corneal tissue on the surface of the black eye, so that it is smooth, regular, and curved just enough to achieve the position of the light focusing on the macula at the bottom of the eye. If it is not made smooth and regular enough, astigmatism manifests itself, and if the curvature is not in place, postoperative myopia undercorrection or overcorrection occurs. Whether the surgical efficacy is satisfactory is also affected by: 1. equipment and engineers debugging good or bad. 2. physician skill level. 3. patient cooperation and biological response to these three important factors.
There are currently two types of laser myopia surgery. One is called laser keratomileusis (PRK), where the laser repairs from the corneal surface. It is only suitable for myopia below 6.00D, too high a myopia to do PRK, prone to corneal scarring turbidity. The other procedure is called laser corneal interlaminar mosaic (Lasik), which uses a special knife to split the corneal interlaminar layers to make a corneal flap, and laser repairs are made within the corneal stroma; it is suitable for both high and low myopia, and the procedure is more difficult, and prone to complications with the flap. My two daughters and have done laser myopia surgery, the effect is good, but ask them how they feel, the sister said "no regrets". But my sister said: "how not regret, I will not do it again even if I die," indicating that laser myopia surgery has both advantages and disadvantages!
Benefits: 1, is currently the most safe and reliable treatment of myopia, both domestic and foreign reports, or our own experiments, for myopic patients with 6.00D or less, long-term stability of postoperative naked eye vision, 92% ≥ 0.5, 70% ≥ 1.0. For more than 6.00D high myopia, the higher the myopia, the worse the long-term effect of surgery.
2. Compared with the charges for the same equipment and technology in the advanced countries of the United States, Germany and Japan, the domestic surgical charges are very low, only the above countries?
3, the domestic physicians have rich clinical experience, preliminary estimates, the number of surgical cases has exceeded 300,000 people. Because of the high technology and low price, it has attracted many foreigners to come to China for surgery.
4, fast. Laser irradiation takes only a few seconds and does not require hospitalization.
Drawbacks: 1, surgical efficacy is not perfect, there are always a small number of surgical patients with complications, individual patients and even infections, eye perforation and other serious complications, resulting in a loss of corrected vision or even blindness, due to the laser surgery is carried out in the healthy eye, the eye could have been equipped with corrective glasses vision can be fully restored, if the surgery led to a loss of vision, then the loss is more than worth it. From this point of view, patients undergoing surgery are risky. Both the surgeon and the patient should think twice before making up their minds about surgery.
2, the current laser myopia surgery in our country seems to carry out some of the abuse, a few units with commercial operation, advertising overstatement, not in the technical level of effort, increasing the possibility of complications.
3, excimer laser equipment and technology is still developing, a few units can not keep up with its development, resulting in patients suffering undue losses.