Editor's Note Yesterday, the 5th Global Chinese Ophthalmology Academic Conference and the 21st National Ophthalmology Academic Conference of the Chinese Medical Association opened in Suzhou, the "Oriental Water Capital". tecnis symfony® (new stepless) continuous vision range - intraocular lens satellite will be held at noon, Professor Yao Ke of the Ophthalmology Center of the Second Affiliated Hospital of Zhejiang University will serve as the chairman of the satellite meeting, Professor Tang Xin of Tianjin Eye Hospital, Professor Zhang Jinsong of Eye Hospital of China Medical University, and Professor Chen Weirong of Zhongshan Eye Center Affiliated to Sun Yat-sen University will be the guests. Professor Li Dexiao from Taiwan and Professor Lu Yi of the Eye, Ear, Nose and Throat Hospital affiliated to Fudan University gave a wonderful lecture, explained in detail the unique design of tecnis symfony® (new levelless), and shared their experience and experience.
Professor Yao, president of the Satellite Society, is the first ophthalmologist in China to use tecnis symfony® iol. Professor Yao mentioned in his speech that tecnis symfony® iol is a continuous visual range iol that provides better middle vision and a longer visual range, and is also the world's first functional iol, which has more glare and halo and less focal iol. At present, for this new iOL, Professor Yao is preparing to carry out clinical research observations of a larger sample.
Li Dexiao: A new era of cataract and presbyopia correction - clinical manifestations of tecnis symfony® (new gradeless) iol
Professor Li Dexiao from Taiwan shared his clinical experience and experience in using tecnis symfony® iol with the doctors present. Professor Li said that halos can be used as an artistic representation of images, but in real life, we do not want halos to exist, which is why he has used multifocal iOL less in recent years. In just half a year, Professor Li has used 50% of the tecnis symfony® iol, and he believes that the tecnis symfony® iol has opened a new era of cataracts and correction of old vision, which expands the depth of field and extends the range of vision.
Current cataract patients are increasingly demanding postoperative visual quality, but cataract surgery is a flawed procedure – it "creates" presbyopia, even in their twenties, after cataract surgery. There are three alternative solutions to the problem of presbyopia after cataract surgery that is currently prone to occur - multifocal iol, modulated iol or small pupil iol (monovision), but these three methods still have some disadvantages.
The principle of multifocal iol is to distribute light on two different focal points at the same time, which will bring visual problems such as glare and halo, while the contrast sensitivity is reduced, and waxy vision appears. In addition, the depth of field of multifocal iol is too short, and patients often need to adjust the focus all the time, resulting in inconvenient life.
Traditional multifocal iol, residual refractive error is large, for patients with previous laser surgery will have severe aberrations, while there will be halo, glare, decreased contrast sensitivity, depth of field stenosis, etc., postoperative need about half a year of neural adaptation period, which needs to be fully explained to the patient before surgery, Professor Li also joked about these shortcomings as "traps". The emergence of tecnis symfony® iol does a good job of avoiding these shortcomings of multifocal iol and filling in this "trap". Tecnis symfony® iol's patented diffraction grating notch design extends the focus and increases the field of view, making it continuously clear to see far, center, and close (Figure 1). The extension of the focus does not expand or thicken the diffusion circle, so it is very inclusive. In addition, tecnis symfony® iol has a patented chromatic aberration elimination technology that increases contrast sensitivity and increases night vision through the elimination of chromatic aberration (Figure 2).
Figure 1. Tecnis symfony® iol's patented diffracted grating notch design
Figure 2. Tecnis symfony® iol's patented chromatic aberration elimination technology (right) improves contrast sensitivity
In Taiwan, the use of mobile phones is very common in the elderly, so it is necessary to meet the patient's near vision needs; and when performing sports such as golf, patients want to have better middle-distance vision; and patients do not want to have glare and halo problems at night. Although tecnis symfony® iol has many rings in appearance like multifocal iol, it only forms a wide focal point (focal line), thus avoiding the problem of brain adaptation and interference between focal points caused by multifocus, and providing true continuous full functional vision.
Next, Professor Lee shared his experience with tecnis symfony® iol. Professor Lee's first patient to use tecnis symfony® iol was a monocular cataract, one-eye implantation of tecnis symfony® iol, and the postoperative patient had a visual acuity of 20/20, j3. The second patient had monofocal iol implanted in one eye and tecnis symfonyiol®in the other, and the postoperative patient had vision 20/20, j3. The third patient had tecnis symfony® iol implanted in both eyes, with vision of 20/25,j2 when implanted in one eye, compared with 20/20,j1 after both eyes were implanted. It can be seen that it is easy to use tecnis symfony® to achieve 20/20 vision, and the first three cases also increase Professor Li's confidence in using it. So far, Professor Li has completed 91 cases of implantation of tecnis symfony® iol, of which only three patients have developed halo or glare. In combination with other iOL, tecnis symfony® iol more jiao iol is more unrestricted, can be almost any other iOL.
Professor Lee concluded that his overall experience is that the tecnis symfony® iol is very safe, effective and simple. His experience includes: preoperative patient selection is more careful, need to carry out adequate preoperative communication, give rational and reasonable expectations; intraoperative, need to ensure a perfect surgical operation, so that the iol is centered; secondly, it is also particularly necessary to pay attention to the patient's eye surface and the presence of dry eyes, optimize the patient's eye surface; in addition, the doctor at the beginning of the use of tecnis symfony® iol, it is best to start with a simple case; in addition, the doctor's postoperative listening to the patient's complaint is also very important.
Finally, Professor Li shared his clinical observations of tecnis symfony® iol. He found that more focal iol, tecnis symfony iol postoperatively decreased sensitivity to halo, glare and contrast sensitivity® occurred less, required less neural adaptation, had fewer restrictions on the selection of contralateral eye iol, had fewer patients complaining postoperatively, and had fewer postoperative conversations and follow-up visits. At the same time, tecnis symfony® iol is a high-quality continuous vision iol with reliable postoperative visual outcomes and good patient satisfaction.
Professor Chen Weirong said in his review that tecnis symfony iol used its unique patented technology, so the symptoms such as halo and glare after surgery® were significantly reduced, which is a consensus reached by doctors who have used the iol. And tecnis symfony® iol, through its patented technology, can achieve good far vision and satisfactory near vision, especially suitable for modern people's lifestyle and habits.
Professor Lu Yi: Tecnis Symfony® (New Stepless) Continuous Line of View — Optical Design and Clinical Application of IOL
Professor Lu Yi said at the satellite conference that since the first iOL implantation, cataract surgery has become one of the most successful eye surgeries. The application of multifocal iol allows patients to see far and near. However, in the process of applying multifocal iol, some defects were still found - the patient's contrast sensitivity and dark vision decreased, and visual problems such as glare and halo appeared.
Professor Lu went on to share the first case of his tecnis symfony® iol implant. The patient was a 62-year-old woman with preoperative vision of 0.15, and the procedure and implantation were the same as those of other tecnis iols. Repeated postoperative questioning of the patient denied any glare and halo. On the first day after surgery, the patient's near vision reached 1.0 and the medium and long distance vision reached 0.8, and the out-of-focus curve showed a mild myopia state. At day 10, the patient's near vision decreases slightly, the far vision improves, and mild farsightedness drifts occur (Figure 3).
Fig. 3.Naked-eye vision (top) and out-of-focus curve (bottom) of patients on day 1 (d1, blue line) and day 10 (d10, red line) after implantation of tecnis symfony® iol
After building confidence in the first successful case, Professor Lu performed 10 more cases of tecnis symfony® iol implants, of which 6 cases had detailed clinical evaluation results. In the follow-up of these 6 patients, the patients all denied halos and glare, so it can be seen that tecnis symfony® iol basically solves the problem of multifocal iol main halos and glare. Patients have good medium and far vision and satisfactory near vision after surgery (Figure 4), and the out-of-focus curve remains between -1.5d-+1.0d at 0.8-1.2 (Figure 5). In addition, two of the six patients with astigmatism (≥1.0d) also achieved good naked-eye vision after surgery (Figure 6), demonstrating that tecnis symfony® iol has a high tolerance to astigmatism. Professor Lu also compared these two patients with two other patients who had been implanted with tmf multifocal iol at the same time, and the results showed that the naked eye vision tecnis symfony® iol was better than that of tmf multifocal iol, and from the out-of-focus curve, it can be seen that the overall vision of tecnis symfony® iol is better than that of tmf multifocal iol (Figure 7).
Figure 4: Naked eye vision at the last follow-up
Figure 5.Out-of-focus curve after implantation of tecnis symfony® iol by patients
Figure 6: Naked-eye vision in a patient with astigmatism after implantation of tecnis symfony® iol
Figure 7. Tecnis symfony® iol compared with tmf multifocal iol after implantation
Why does tecnis symfony® iol have better results? First of all, tecnis symfony® iol has its patented new echelette diffraction technology, which optimizes the height and contour of the diffraction grating, that is, changes the phase of the light in each region, so that the phase length interference of the light occurs at a series of distances, resulting in an extension of the focal line, thus changing the focus to the focal line. In multifocal iol, due to the formation of two independent focal points, there will be interference between the two focal points, which is the main reason for the decrease in glare, halo and contrast sensitivity; and tecnis symfony® iol achieves the depth of field extension of vision by extending the depth of focus, changing "spectroscopy" to "extending the focal line", so that there is no interference between multiple focal points (Figure 8), which avoids the main visual problems of traditional multifocal iol to a certain extent. It provides true continuous and high-quality vision over a range of distances, improves contrast sensitivity and significantly reduces visual distractions (halos and glare). As can be seen from the out-of-focus curve, the tecnis symfony® iol achieves good focus in the 1.5d range, with a slight drop at 2.5d (Figure 9).
Figure 8. Tecnis symfony® iol novel echelette diffraction technology
Figure 9. tecnis symfony® iol out-of-focus curve
Second, another patent from tecnis symfony® is its technology to eliminate chromatic aberration. By eliminating chromatic aberration, you can increase contrast sensitivity and reduce flares. The results also confirmed that tecnis symfony iol has a similar contrast sensitivity® to monofocal iol, while traditional multifocal iol has a 38.57% lower contrast sensitivity than monofocal iol. Professor Lu said that the ability of tecnis symfony® iol to tolerate relatively high astigmatism may also be related to its improved contrast sensitivity.
Multiple large clinical studies have shown a low incidence of halos (about 10% of moderate and severe) in tecnis symfony® iol, while 66.7% of patients with trifocal iol implantation reported moderate or severe halos at 3 months postoperatively, and 32.7% of patients with competitor a+2.5d iol reported moderate or severe halos at 6 months postoperatively. Another finding is that tecnis symfony® iol can provide 20/20 (1.0) vision in the 1.5d range of astigmatism, while multifocal (bifocal and trifocal) iols have impaired vision at various distances in the presence of astigmatism.
Next, Professor Lu shared the main points of surgery for implanting tecnis symfony® iol. First of all, in terms of patient selection, the selection criteria are basically equivalent to the traditional multifocal iOL, but the indications can be relaxed. Secondly, Professor Lu suggested that the non-main eye reserves -0.5~-0.75ds, while the main visual eye reserves 0~-0.5ds, so that better full vision can be obtained. Furthermore, the perfect sac tearing is very important for implanting tecnis symfony® iol, and the femtosecond laser can also be used to assist the sac tearing process. Also, pay attention to the kappa angle.
Finally, Professor Lu concluded that tecnis symfony® (new stepless) continuous line of view iol uses a unique patented technology that turns the focus into a focal line with an adjustment range of 1.5d-2d, while reducing visual distractions, reducing the occurrence of glare and halos, and improving contrast sensitivity. From the current data, tecnis symfony® iol has achieved very encouraging results.
After the wonderful lectures of the two professors, they entered a lively on-site Q&A discussion. The doctors present consulted the experts present on the issues® of out-of-focus curve, implantation techniques of tecnis symfony iol, and tecnis symfony® iol power calculation and received detailed answers from experts. Professor Zhang Jinsong shared his biggest experience of using tecnis symfony iol, implanting iol during surgery® to observing iol after surgery can truly appreciate the unique artistic sense of tecnis symfony® iol, and it can really provide excellent full vision. Dean Tang Xin said that in the choice of the degree of iol, it is necessary to take into account the difference in the patient's individual adjustment ability, which should be flexibly applied in the clinic, and pay attention to distinguishing the main visual eye when implanting high-end iol, and the two eyes have different degrees of choice of iol, so that the vision covered can be wider. In addition, skilled surgical techniques and a full understanding of high-end iOL are also the basis for ensuring postoperative results.
At this point, the tecnis symfony® (new stepless) continuous field of view- intraocular lens satellite will be the perfect end. We believe that a new era of cataracts and correction of old vision is beginning.