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FAQ about laser correction ReLEx SMILE: yes, in Russia there is, but no, in Russia there isn’t

  • суббота, 9 мая 2020 г. в 00:12:57
https://habr.com/en/company/klinika_shilovoy/blog/501066/
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— Are small-invasive laser vision correction operations done in Russia using the Small Incision Lenticule Extraction method?

Yes, about 10 years already. Every year, more and more at conferences of ophthalmologists, questions arise not at the level of “What is this?”, But at specific practical nuances of technology. VisuMax lasers exist in several clinics in Russia, but it is much less used under ReLEx SMILE than under femtoLASIK. Historically, it happened in Russia that this technology is little used in the central part and is actively used beyond the Urals.

— What is the story with licenses for specific operations?

Zeiss sells cones with licenses. A cone — a replacement part adjacent to the eye — is purchased with a license to use a laser procedure, usually in batches of 10 or 100 operations. For example, 10 cones and 10 licenses are received. Licenses are driven through the laser menu, and it allows you to use the appropriate cones for the appropriate program types. Licenses for SMILE separately, for femtoLASIK separately, for FLEX, rings and additional corrections are also separate licenses. Most manufacturers of femtosecond and some excimer lasers have a similar situation. Licenses for excimer operations are not needed, perhaps, except on models of about 5 years old and older.

— And you can not get such a license for SMILE?

Easily. Firstly, this module in the laser is as an expensive option, so the device itself without the SMILE option is cheaper. Secondly, if this option is available, then licenses to carry out the operation ReLEx SMILE can be acquired only after conducting 5–10 test runs on pig eyes, then performing at least 10 femtoLASIK operations on patients, then 50 FLEX operations, and only after that Buy a SMILE license for a specific surgeon.

— I figured out how to get around this ...

The license for SMILE costs 200–300 euros per eye in different regions of the world. It will not work out two operations instead of one, it will not be possible to make SMILE under the femtoLASIK license. In the event of a technical failure of the accounting system of operations or problems with the firmware, the spent licenses are not returned (in case someone calls “warranty” cases of breakdowns).

— Why is everything so strangely arranged?

Because SMILE is now a new and expensive technology, it is also the safest in terms of the risk of irreversible side effects. Well, and corresponds to the trends in surgery in general — the transition to endoscopic technique, and not through a large incision. As a result of the technology itself — there are requirements for the manual skills of surgeons. And 90 out of 100 surgeons-ophthalmologists who massively perform operations on excimer lasers have long done nothing with their hands. That is, it is much easier to master the technology for those involved in standard eye microsurgery — cataract operations, glaucoma, and so on. Accordingly, the clinics have a question — either to sell at a low price with a low cost of the surgeon’s work, retraining the “ordinary” laser specialist, or not to invest in expensive “space” equipment and offer operations to their patients using old, traditional technologies. Even harder, for example, in the UK — correction clinics for the most part do not train their doctors. Equipment is purchased there, and then practitioners nearby are invited as freelancers to specific operations. They do not diagnose them, they are given an opinion on the patient, the laser and an hour of time. Everything, operation is ready.

— What exactly does the surgeon's skill influence?

The accuracy of the separation of lenticles in parametric geometry is when it is already formed by two laser cuts from the bottom and from the top, and it needs to be taken out of the cut from the side.

The cavitation cut is 10–15 microns, it is not always smooth, there are points of tissue glazing (according to manual sensations, like the lightest, slightly damp napkin lays on the table).

Accordingly, if the surgeon is inexperienced, then he has two options: to risk tissue injuries when manipulating the spatula is a bad option, or to set up such regimes when the lenticule is detached and taken out much easier. This means that a larger incision can be used (Walter Sekundo, as an inventor and a long-term practice with very significant experience and more complex other manual operations, insists on a 2.5 mm incision. However, in Russia they do 4.5 mm, or “Wildly” for him — 6 mm). On the other hand, by the way, an ophthalmologist with an incredibly extensive experience in operations Rupal Sha from India makes an entrance of only 1.5 mm, and gets a lenticle through this incision.

The second option to facilitate lenticular secretion — an unjustified change in laser frequency, which gives a “roasted” cornea due to greater heat absorption by the bowman membrane tissues, and increases the risk of side effects (innervation disorder, corneal carcass deformity) —to reduce many of the technology's benefits. By the way, the “roasted” here roughly corresponds to what the excimer laser does with LASIK or femtoLASIK. In excimer lasers during surgery, there is even a peculiar smell of “scorched tissues” and suction is used to remove gas vapors.

There is still a chance of an error at the lenticula extraction stage. Any lenticular surgery requires certain skills, of which the easiest is to move breathing one-to-one to the beat with the patient so that the instrument in the eye remains stable.

— Ok, if the operating frequency of the laser is correct, the cut is 2.5–3 mm, what is the error rate in the manual part of the operation?

The generalized probability of occurrence of complications in world practice (both reversible and irreversible together) is 0.5–1%. Apart from really “idiotic” cases with namesakes, most of the problems arise because of incorrect or insufficient diagnostics (probably putting the wrong patient on the table is also part of the diagnosis, right?). The most unpleasant irreversible complication is the corneal protrusion due to the loss of stiffness of the frame, that is, a significant violation of its biomechanics. It is possible if the patient has either miraculously passed diagnostics with an error, or if a defect of the stroma is opened, which could not be recognized by existing scanners (by the way, the quality of the equipment for diagnostics of clinics still arises — they often try to save on this). Comprehensive preoperative examination is an important thing. According to our European standard, the clinic uses 15 different studies on devices, it takes about 2 hours, allowing you to eliminate the inaccuracy that came, for example, from other optometrists. For 15–20 minutes, only a few basic tests can be performed: in general, this could be limited to, but we really do not like surprises during operations.

— What is the story with namesakes?

Walter Sekundo just told her last year at a conference in Moscow at the Institute of S.N.Fedorov. In one foreign clinic, the “conveyer” process confused two patients. The first with a myopia-4 and astigmatism went to LASIK, received a correction, and only at the end a local performer understood the error. The doctor then claimed: «My optometrist is to blame.» Walter was called to correct what they had done, and he had only one question when analyzing the operation, and he came down to why this most attentive doctor did not control everything himself.

Walter himself, by the way, understands (as I do) that our names are written directly in the names of the clinics, and the name there is a full responsibility. In the case of Walter, not only for the clinic, but also for the whole technology, he checks everything manic and calm three times. Colleagues joke about him — “Three hundred percent German.” This is due to the three-time verification protocol, mandatory for SMILE, performed under a license.

— What will happen if the lenticule bursts during extraction or separation?

This will somewhat complicate the work, but in experienced hands nothing serious. In general, it can be extracted in parts, but in its entirety — faster, easier and more comfortable for the patient.

— What do surgeons learn from FLEX-methods for ReLEX?

On pig eyes, because they have the most similar to the human cornea. In Turkey — on sheep's eyes. Training «patients» are delivered to the operating room without the rest of the pig. Then there are patients who are fully aware of the risk (most often they are acquaintances whom the doctor performs the operation for free — or people who are in the queue for a free correction for such cases, realizing that the risks after pigs are minimal). In this regard, the story of Walter with pigs is very remarkable. He used to treat them in the spirit of “order another half a bucket of eyes to a lecture at the slaughterhouse” — everything is rational, a pig and so dead, someone's eyes will be useful. But experiments on the development of SMILE were carried out precisely on living specimens — more precisely, they were evaluated for long-term effects. We received permission from the ethics commission, received pigs, and took the laser to the veterinary institute. They did it on the spot, took the vet to put the patients under anesthesia. At the time of the operation, the pigs were small pigs, but after 3 months of observation, they had gotten to a very impressive size. Walter Zeiss singled out two huge nurse on the wind profile, and they dragged patients, and a pretty veterinary doctor followed them. And then everything went well, and for the last proof it was necessary to do an autopsy on the already familiar pigs. According to the rules — it is necessary to kill and take away the eyes. Moreover, that additionally offended German colleagues — “to kill just like that,” because, according to the rules, it is impossible to allow prototypes for meat.

As for me, when a little more than 6 years ago we went to Germany to study how to do FLEX and SMILE (I studied in several centers, including the university clinic in Marburg), one simple requirement stood for the professor and creator of the technology Dr. Sekundo — at least 1000 manual operations over the past 5 years. I consistently do about 3,000 abdominal operations per year (about 10% of corrections, then a cataract, glaucoma, retinal detachment, various mechanical injuries; some operations are for 20 minutes, but there are also 1.5-2 hours). Our holding surgeons have at least a thousand operations a year.

Now SMILE makes about 80% of myopia corrections in our clinic. In addition to Germany, centers with a huge number of SMILE are still in Thailand, Egypt, Turkey, India, Latin America, there is one center in China — scientific work is being conducted in these countries.

— Where else in Russia do people with SMILE experience?

In Russia, 10 laser installations VisuMax, and at all, without exception, make femtoLASIK perfectly. As for SMILE, the long successful experience of work with colleagues from the branches of the IRTC of them. S.N. Fedorov in Irkutsk, Khabarovsk and Yekaterinburg. The number of SMILE operations performed is several thousand in each of them. Surgeons from these clinics are the authors of the new instruments, for example, Oleg Aleksandrovich Kostin is known for his engineering solutions — Kostin's spatula is one of the most successful instruments for today.

— Is it necessary to do SMILE?

Not. First of all, if you are completely satisfied with the glasses, you can not make a correction at all. They have their drawbacks, and they, and contact lenses, but more on that later. After the diagnosis, we usually do not recommend the patient the operation directly, but give forecasts and recommendations. The doctor does not decide for the patient, but gives him maximum information and the right to choose. In some cases, femtoLASIK or PRK is preferable for the indication, sometimes the choice is made because of the price, sometimes because of 30 years of clinical practice. Correspondence consultations are very approximate. Attempts to recommend some kind of operation without an accurate diagnosis of a particular patient and without understanding what kind of lifestyle he plans to lead (for example, if we learn from the patient’s history that the patient is working as a jeweler or sewing, then we change the long-term forecast accordingly). However, if with equal opportunities from a medical point of view, you choose between SMILE and femtoLASIK, the SMILE technique is statistically better. Correction accuracy on 6th generation lasers (VisuMAX) corresponds to or higher than other methods (with correction from -2 diopters, less — more precisely femtoLASIK, less than -1 — more precisely PRK), and the risk of irreversible complications is significantly lower.

— I am afraid to do now, because with age-related changes are possible ...

One of the most common myths is that with age the “minus” will turn into a “plus” and then you probably won't need glasses. This is not true. If you simply imagine the eye as a lens system, it turns out that the cornea and the lens have the most refractive power. The optical power of the cornea in most cases varies slightly with age. The lens with its ligament apparatus is the main tool with which we examine objects in the distance and near, changing the focal length of the eye. This is similar to setting the focus in a camera. In youth, it happens easily. In the lens, changes begin to occur with age — its density, configuration, size, and transparency change. These changes in the lens of even a medically healthy person over 40 years of age result in presbyopia (age-sightedness). 100% of people are subject to this process, regardless of whether they have optics of the eye — with short-sightedness, long-sightedness, with or without astigmatism. This is manifested as:

  1. A man with a beautiful eyesight begins to read with glasses.
  2. A nearsighted person stops seeing at close range, being in glasses for distance and for reading he will be forced to wear a second pair of glasses or read when removing glasses for distance and bringing the text closer to his eyes.
  3. Far-sighted begins to wear 2 or even 3 pairs of glasses — for distance, for medium distance (for example, for a computer) and the strongest glasses — for close distance.
  4. The one who also has astigmatism, sees not clearly at all distances and also requires several pairs of glasses.

Thus, presbyopia weakens the accommodation of the eye every year — the ability to focus at different distances. On average, by the age of 60, it is completely lost.

Of course, each refractive surgeon always takes into account the patient's age when choosing a correction algorithm and method of correction, with patients of presbyopic age with transparent lenses over 45–50 years of age, the issue of the expediency of myopia’s full correction is discussed, since the residual minor undercorrection on one (non-imagined eye) or both eyes has eased would be a visual load for near. Farsightedness and astigmatism always correct completely, as they interfere with vision and into the distance and near.