Frequency, causes and course of multifocal intraocular lens explantations
The study "Frequency, causes and course of explantation of multifocal intraocular lenses" by Dr. Omid Kermani and Dr. Georg Gerten investigates how often and why multifocal intraocular lenses (MF-IOLs) have to be removed after implantation. These lenses are often implanted after cataract surgery or refractive lens exchange to improve vision.
Multifocal intraocular lenses (MF-IOLs) are artificial lenses that are often implanted in the eye as part of cataract surgery. These IOLs have multiple focal points that allow for both near and distance vision. Despite their advantages, in rare cases it may be necessary to remove the lens again (e.g. if the visual acuity changes significantly).
Between 2009 and 2014, a total of 1438 eyes were fitted with hydrophobic, aspheric, diffractive, multifocal posterior chamber lenses of the type Acrysof ReSTOR and ReSTOR Toric (Alcon, Fort Worth, USA) at the Neumarkt Eye Clinic in Cologne. Of these cases, 78% were due to cataracts and 22% were refractive lens replacements. All surgeries were performed under topical anesthesia with ultrasonic phacoemulsification. Since 2013, the femtosecond laser has also been used, which enables even more precise removal of the lens. The data was evaluated using digital patient records.
Overall, the MF-IOL had to be removed in 12 out of 1438 cases, which corresponds to a rate of 0.83%. The reasons for the explantations were mainly a deviation from the target refraction. In these rare cases, optical discomfort occurred, which made it necessary to replace the IOL with a monofocal lens.
Diffractive MF IOLs of the Alcon Acrysof ReSTOR type are generally well tolerated and are rarely removed. Only in 0.28% of cases were explantations due to optical complaints. In the remaining cases, the reasons for removal were not due to the optical geometry of the lens.
Overall, the IOLs examined all exhibited a high level of tolerability and patient satisfaction. Possible side effects such as blurred vision can be remedied by subsequently replacing the lens. The use of femtosecond lasers and modern surgical methods helps to increase the precision and safety of the procedures.
Cataract surgery - cause of the disease and surgical procedures for treatment
A cataract is an eye disease in which the lens becomes cloudy, resulting in long-term visual impairment. This clouding is caused by the accumulation of dead cells and proteins in the lens, which should normally be clear. The development of a cataract can be influenced by various factors such as age, genetic predisposition, diabetes, smoking, UV radiation and certain medications.
Cataracts are usually diagnosed by a thorough eye examination, during which the ophthalmologist can determine the opacity of the lens. Symptoms of a cataract include blurred vision, sensitivity to light, altered color perception and double vision. The treatment of cataracts mainly consists of surgical procedures in which the cloudy lens is removed and replaced with a clear artificial lens. The operation is usually performed on an outpatient basis and is one of the safest and most effective medical procedures.
Research has investigated various approaches to the treatment and prevention of cataracts. Studies have shown that the use of aldose reductase inhibitors and antioxidants in particular can help to prevent or treat diabetic cataracts. In addition, the importance of continuous monitoring of intraocular pressure is emphasized in order to detect early changes that cannot be detected with conventional measurements.
Despite the high success rate of cataract surgery, some complications are possible, including retinal detachment and infection. Current research is therefore intensively searching for new pharmacological approaches to further improve the treatment of cataracts and reduce complications. Advances in the localization of surgical incisions and technologies have helped to optimize the accuracy and efficiency of cataract surgery.
In summary, cataract is a common eye disease characterized by clouding of the lens that impairs vision. Diagnosis is made through a thorough examination, and treatment usually involves surgery to remove the cloudy lens. Research is focusing on new therapies and technologies to further improve the results of cataract surgery and minimize complications.
You can find more information on cataract treatment methods on our website under “Services”.
Sources:
· Cataracts. Thompson, Lakhani. 2015. Primary Care: Clinics in Office Practice.
· Diabetic Cataract—Pathogenesis, Epidemiology and Treatment. Pollreisz, Schmidt‐Erfurth. 2010. Journal of Ophthalmology.
Aphakia correction with a customized anterior chamber lens
Aphakia is a condition in which the natural lens of the eye has been removed or is missing. This can be caused by various reasons such as surgery, injury or congenital anomalies. Treatment for aphakia often involves the implantation of an artificial lens to restore the patient's vision, in addition to wearing glasses and contact lenses.
There are several techniques and approaches to treating aphakia, including iris claw fixation (an IOL in the anterior or posterior chamber) and sulcus fixation, which are equally effective and safe.
However, with the sulcus lens, complications such as corneal edema, retinal detachment and intraocular hemorrhage or dislocation and tilting of the IOL have been described in the past. The currently available anterior chamber lenses also have disadvantages such as corneal edema, uveitis symptoms, glaucoma or macular edema. Even with modern forms of anterior chamber lenses, astigmatism or iris trauma still occur.
For this reason, Dr. Kermani developed a new anterior chamber lens. Thanks to its special shape with three arms, it can be fixed more securely in the eye. The lens is also made of hydrophobic acrylate, which makes it flexible and foldable. The diameter is 13 mm. Another major advantage is that the anterior chamber lens can be replaced at any time in the event of intolerance or changed requirements.
In a lecture, Dr. Kermani presents three patients who have been implanted with the new lens. The indications for this were aphakia, IOL subluxation and posterior capsule rupture.
You can find the publication here.
It should be noted that most patients tend to be older and have already undergone cataract surgery. The expected wearing time of the lens is therefore significantly shorter than with an IOL that is inserted as part of cataract surgery.
The decision to use an anterior chamber lens or an alternative must therefore always be weighed up individually with regard to the patient's medical situation and refractive goals.
Improved laser technologies - Tübingen aims to advance refractive surgery
The Section for Experimental Ophthalmic Surgery and Refractive Surgery at the University Hospital of Tübingen is actively involved in various projects aimed at improving refractive surgery. One focus is on innovative approaches in laser technology and personalized treatment methods that are individually tailored to the needs of patients.
Laser technologies play a crucial role in refractive surgery as they enable precise and effective procedures. By using the latest laser technology, various procedures such as LASIK (laser-in-situ keratomileusis) or femto-LASIK (femtosecond laser-assisted LASIK) can be performed. These techniques allow individual adaptation to the specific requirements of each patient, leading to precise results and faster recovery.
The section in Tübingen focuses on improving these proven approaches and deals with personalized treatment methods in refractive surgery.
These efforts are aimed at optimizing patient outcomes and improving the overall quality of refractive surgery.
Specifically, this means that surgeons take into account the unique characteristics of each patient to develop tailored solutions and personalized treatment methods. This personalized approach can increase treatment efficiency and minimize the risk of complications as they are specifically tailored to individual needs and anatomical conditions.
The basis for this is the three-dimensional measurement of the eye, which creates an individual virtual model of the eye.
A significant advance was the development of a new Placido topometer, which was launched on the market by an industry partner. For the first time, it is now possible to calculate intraocular lenses using real ray tracing (RRT). In an updated version, the Placido topometer is combined with an optical biometer based on partial coherence interferometry (PCI) technology. The great advantage of this innovation is that it is easy to use for the individual calculation of intraocular lenses without having to rely on the old empirical formulas.
The impact of the COVID-19 pandemic on refractive surgery
Since the coronavirus pandemic in 2020 at the latest, medical protective measures such as regularly disinfecting hands or wearing a mask when you have a cold have become part of everyday life for many people. Spectacle wearers in particular are faced with the problem of fogged-up glasses. Contact lens wearers are also increasingly struggling with dry eyes due to the air escaping from under the mask.
Thanks to medical advances, refractive surgery now offers many patients a long-term solution for freedom from glasses. In addition to classic Femto-Lasik, there is also the option of implanting an ICL (anterior chamber lens) or a refractive lens exchange, which is particularly suitable for patients with thin corneas.
The current social changes in terms of individual health awareness raise the question of whether refractive services for freedom from spectacles will be used more frequently after the pandemic.
The paper by Kermani et al. deals with the changes that the virus has brought to society as a whole and, as a consequence, to refractive surgery. Kermani et al. state that since the beginning of the pandemic, feelings of anxiety in connection with social distancing have become more widespread in society. As a result, there has been an increase in personal protective measures, such as wearing masks or face coverings. Meanwhile, the European COVID-19 Cataract Group (EUROCOVCAT) reports an increase in demand for corneal and refractive cataract surgery, which initially posed a major challenge for European ophthalmologists. Specifically, an increase of 25% (as of 2021) was reported compared to the same period in the previous year for patients presenting for refractive surgery for the first time.
At this point, the question arises as to whether this is due to a change in health awareness and the increased use of visual aids. However, this must be countered by the fact that, according to EUROCOVCAT, fewer procedures were performed during the pandemic that now need to be repeated.
The paper by Kermani et al. deals with the changes that the virus has brought to society as a whole and, as a consequence, to refractive surgery. Kermani et al. state that since the beginning of the pandemic, feelings of anxiety in connection with social distancing have become more widespread in society. As a result, there has been an increase in personal protective measures, such as wearing masks or face coverings. Meanwhile, the European COVID-19 Cataract Group (EUROCOVCAT) reports an increase in demand for corneal and refractive cataract surgery, which initially posed a major challenge for European ophthalmologists. Specifically, an increase of 25% (as of 2021) was reported compared to the same period in the previous year for patients presenting for refractive surgery for the first time.
At this point, the question arises as to whether this is due to a change in health awareness and the increased use of visual aids. However, this must be countered by the fact that, according to EUROCOVCAT, fewer procedures were performed during the pandemic that now need to be repeated.
The study by Kermani et al. also points out that the demand for refractive surgery has been increasing for years and that the pandemic has only slightly reduced this demand.
The development of the femtosecond laser
The femtosecond laser is currently used in various ophthalmic surgery procedures to achieve more precise results than would be possible using the "classic" surgical scalpel.
But how did this come about and how has laser technology developed in recent years?
The femtosecond laser was first used in ophthalmology for cataract surgery in the early 2000s. Initially, the focus was on evaluating its efficacy and safety in creating precise capsulotomies and lens fragmentation during cataract surgery. Over the years, the technology has evolved. Today, the femtosecond laser is used in refractive surgery as well as in cataract surgery and subsequent post-cataract treatment, known as capsulotomy.
One of the main advantages of femtosecond laser-assisted cataract surgery is the precision it offers when fragmenting the body's own lens during cataract surgery or creating a flap during LASIK. According to a study (Dick & Schultz, 2017; Titiyal et al., 2016 see list of sources below the article), this is particularly advantageous in patients with a low preoperative endothelial cell count.
Particularly in the field of cataract surgery, femtosecond lasers have been found to offer better wound architecture and lead to less endothelial cell loss compared to conventional cataract surgery. Femto lasers also offer the ability to customize the size and position of the capsulometry for patients with zonular weakness, resulting in more precise outcomes.
As a result, the femto laser has become increasingly popular in cataract surgery among ophthalmic surgeons due to its higher precision and reproducibility as well as the potential for better refractive results.
In summary, the development and integration of the femtosecond laser has revolutionized the field of ophthalmic surgery. In the past, the laser has helped to improve the precision, safety and patient satisfaction of ophthalmic surgery.
The treatment of glaucoma - how has the medical standard changed in recent years?
In recent years, advances in the treatment of glaucoma have reshaped the standard of care for this disease. One significant advance has been the integration of optical coherence tomography (OCTA) into multimodality imaging to assess various retinal conditions (Spaide et al., 2018). OCTA technology has enabled automatic quantification of ocular structures and detection of subtle changes over time, revolutionizing glaucoma management. In addition, spectral-domain optical coherence tomography (SD-OCT) has greatly improved the ability to detect glaucoma progression, allowing for more precise monitoring and adjustment of treatment (Abe et al., 2015).
Nanotechnology has emerged as a promising avenue for glaucoma therapy, offering new approaches to medical and surgical treatment, including neuroregeneration. This shift towards more targeted and effective treatment strategies is a significant development.
Recent research has highlighted the importance of individualized medicine in the treatment of open-angle glaucoma and the need to tailor treatments to each patient to optimize outcomes and minimize risks.
The understanding of glaucoma has evolved to view it as a multifaceted chronic neurodegenerative disease that affects not only the eyes but also the central nervous system. This broader view has led to research into neuroprotective agents and therapies that target the cognitive dysfunction associated with glaucoma.
Advances in surgical procedures, such as trabeculectomy and minimally invasive techniques, offer new options for patients with conditions such as exfoliation syndrome (Sayed & Lee, 2018). These developments aim to improve the safety and efficacy of surgical treatment for glaucoma patients.
Advances in surgical procedures, such as trabeculectomy and minimally invasive techniques, offer new options for patients with conditions such as exfoliation syndrome (Sayed & Lee, 2018). These developments aim to improve the safety and efficacy of surgical treatment for glaucoma patients.
Overall, the current medical standard of care for glaucoma treatment involves a comprehensive approach that integrates advanced imaging technologies, personalized treatment plans and innovative therapeutic modalities. By combining these elements, healthcare providers can deliver more precise and effective treatment to patients with glaucoma, with the ultimate goal of preserving vision and improving quality of life.
Sources:
- Optical coherence tomography angiography. Spaide, Fujimoto, Waheed et al. 2018. Progress in Retinal and Eye Research.
- The Use of Spectral-Domain Optical Coherence Tomography to Detect Glaucoma Progression. Abe, Gracitelli, Medeiros. 2015.
- Management of open‐angle glaucoma by primary eye‐care practitioners: toward a personalised medicine approach. Phu, Agar, Wang et al. 2021. Clinical and Experimental Optometry.
Visual prosthesis for a blind person - intracortical visual prosthesis successfully implanted
The Intracortical Visual Prosthesis (ICVP) is a wireless brain implant to restore vision in blind people. After successful testing on one patient over a two-year period, it has been reported that the prosthesis bypasses the optic nerve and sends images directly to the brain to provide artificial vision. The system consists of 25 miniaturized wireless stimulators with a total of 400 electrodes that are permanently implanted. The clinical trial demonstrated improved navigation ability and the ability to perform basic visually guided tasks.
The patient who received the ICVP had lost his vision due to retinal surgery and an infection. The system includes an external stimulator that is attached to the head to activate the implanted electrodes. The patient wears glasses with a built-in camera that records the environment and sends it to his brain. Visual perception differs from normal vision as it is generated by electrical stimulation of neurons in the visual cortex, which is perceived as a series of phosphenes.
Phillip Troyk, executive director of the Pritzker Institute of Biomedical Science and Engineering and professor of biomedical engineering in Illinois Institute of Technology, Chicago, who led the team, commented on the progress and emphasized the commitment to improving technology to help people without biological sight with everyday navigation and visual tasks. The project is looking for volunteers who have gone blind as adults and have had at least ten years of normal or near-normal vision. Participants will be followed for one to three years after implantation and a recovery period of approximately one month. Several institutions and companies, including the Illinois Institute of Technology and Rush University Medical Center, are collaborating on the project, which is funded by the National Institutes of Health.
author: Celina Prade
What effect does LASIK have on dry eyes?
Dry eyes are a widespread symptom in the population. In particular, people who work a lot in front of a screen or take too few breaks often have itchy or irritated eyes. This raises the question of the extent to which opting for LASIK treatment can have an impact on dry eye symptoms.
Studies have shown that LASIK can be performed effectively in patients with dry eyes and good results are achieved, but there are differences in dry eye outcomes after different refractive procedures.
Experience has shown that the occurrence of dry eyes is a common side effect, especially in the 6 months following LASIK surgery. Dry eyes after refractive surgery are therefore a common complication that occurs to some degree in almost all patients immediately after surgery. This is due to the fact that during the LASIK procedure, superficial nerves can be severed by the flap, which must first regenerate.
At the same time, however, there are also very good options for counteracting this symptomatology. Studies have investigated the use of autologous platelet-rich plasma eye drops for the treatment of post-LASIK chronic ocular surface dry eye syndrome. In addition, treatment options such as topical cyclosporine have been investigated for the relief of post-LASIK symptomatic dry eyes.
Overall, these studies highlight the importance of evaluating and treating dry eyes after LASIK to improve postoperative outcomes and patient well-being.
Sources:
- Dry Eye After LASIK. Toda. 2018 Invest. Ophthalmol. Vis. Sci. link to source.
- Post-LASIK dry eye. Shtein. 2011. Expert Review of Ophthalmology. link to source.
- Autologous Platelet-Rich Plasma Eye Drops for the Treatment of Post-LASIK Chronic Ocular Surface Syndrome. Alió1, Rodrı́guez2, Abdelghany3 et al. 2017Journal of Ophthalmology. link to source.
- Topical Cyclosporine in Treatment of Post-LASIK Symptomatic Dry Eye. Iqbal1, Latif2 2020pak J Ophthalmol. link to source.
author: Celina Prade
Advances in refractive surgery in recent years
Refractive surgery has evolved significantly in recent years, with a focus on improving outcomes and expanding treatment options. Recent developments in refractive surgery have addressed innovative strategies, including preoperative assessment using machine learning and artificial intelligence and improvements in intraocular lens implants for more precise correction of refractive errors. All advances are aimed at providing patients with more personalized and efficient solutions for their refractive errors.
In addition, the introduction of corneal collagen cross-linking (CXL) has changed the treatment of ectasia after refractive surgery with the excimer laser and offers a new approach to the treatment of postoperative complications (Vinciguerra et al., 2010). Extensive research has been conducted on the long-term outcomes of CXL, with successful results observed in the treatment of keratoconus-related ectasia. You can read more about this in the studies by Vinciguerra et al. from 2010 and by Greenstein et al. from 2023. The sources can be found below the article.
In addition, the impact of corneal refractive surgery on glaucoma management has been highlighted, emphasizing the complexity of corneal changes in the diagnosis and monitoring of glaucoma patients (Kozobolis et al., 2017).
There have also been some exciting developments in the training of refractive surgeons in the past. There are ongoing efforts to standardize curricula and prerequisites for residents. These initiatives are designed to ensure that future refractive surgeons receive comprehensive training and are prepared to provide high quality care to patients.
In summary, advances in refractive surgery in recent years have been characterized by technological innovations, improved treatment modalities and an increasing emphasis on education and training in the field. Together, these advances are helping to improve patient outcomes, expand treatment options and ensure the continued evolution of refractive surgery as a specialty in ophthalmology.
Sources:
- · Corneal Collagen Cross-Linking for Ectasia After Excimer Laser Refractive Surgery: 1-Year Results Paolo Vinciguerra, Fabrizio I. Camesasca, Elena Albè et al. 2010J Refract Surgery. link to source.
- · Long-Term Outcomes After Corneal Cross-linking for Progressive Keratoconus and Corneal Ectasia: A 10-Year Follow-Up of the Pivotal Study. Greenstein, Yu, Gelles et al. 2023Eye &Amp; Contact Lens: Science &Amp; Clinical Practice. link to source.
- · The Effect of Corneal Refractive Surgery on Glaucoma. Kozobolis, Konstantinidis, Sideroudi et al. 2017. Journal of Ophthalmology. link to source.
The quality of life of myopia patients - contact lens and spectacle wearers vs. correction by refractive surgery
The study by Shams et al. compares the quality of life of people with myopia who have undergone refractive surgery with that of spectacle or contact lens wearers and emmetropes. 240 students aged 18-30 years were studied using quality of life questionnaires. The participants were divided into two groups: Myopic individuals with visual aids, those with refractive surgery. The results were also compared with the responses of people with normal vision. Data was collected through observation, interviews and questionnaires.
The results of the study show that people who have undergone refractive surgery have a better vision-related quality of life than spectacle or contact lens wearers. Interestingly, the percentage of women who had undergone refractive surgery was higher than that of men, which is consistent with previous studies. Refractive surgery may be more attractive to women due to cosmetic benefits.
Quality of life was examined in various aspects, such as visual clarity, expectations and activity limitations. It was found that a decrease in visual acuity is associated with a deterioration in quality of life. Lower expectations of vision correction were also associated with a higher quality of life.
The study has some limitations, such as the lack of clinical examinations and the estimation of myopia levels by observing the lenses. Reasons for the reduction in quality of life may be a lack of flexibility or the ability to exercise or swim. Future research could include clinical examinations to obtain more accurate results.
Overall, the study shows that refractive surgery can improve the quality of life of people with myopia, although it may not reach the level of emmetropes. The results emphasize the importance of the choice of vision correction method for quality of life and highlight the benefits of refractive surgery. It is important to emphasize that individual consideration of patient needs and experience is the most important criterion for deciding on vision correction.
author: Celina Prade
source: Shams et al., 2015).https://eandv.biomedcentral.com/articles/10.1186/s40662-018-0110-5
Preventing blindness? New insights into the microbial secret of inherited eye diseases
Research by scientists at UCL and Moorfields University has uncovered an intriguing link between gut bacteria and inherited eye diseases that could have potentially revolutionaryimplications for preventing blindness. This groundbreaking study, published in the journal Cell and led by researchers in China, focuses on the so-called CRB1 gene, which is expressed in the retina and is crucial for regulating the blood-retinal barrier. Mutations in this gene are often associated with inherited eye diseases such as Leber's congenital amaurosis(LCA) and retinitis pigmentosa (RP).
The researchers found that the CRB1 gene also plays a key role in maintaining the integrityof the intestinal tract. Mutations can cause harmful bacteria from the gut to enter the eye, causing damage that can lead to vision loss. Interestingly, they found that treatment with antimicrobials, such as antibiotics, was able to prevent vision loss in mice, even if the affected cell barriers in the eye were not restored.
This discovery is particularly significant as inherited eye diseases are the most common cause of working-age blindness in the UK. The development of treatments has so farfocused mainly on gene therapies. The ability to combat inherited eye diseases throughsimple antimicrobial treatments could therefore represent a significant advance in treatment.
Professor Richard Lee from the UCL Institute of Ophthalmology and Moorfields Eye Hospital NHS Foundation Trust, co-author of the study, also highlighted the potential impact of thesefindings. He emphasized that this opens the door to new treatments for CRB1-associatedeye diseases and raises the hope of preventing blindness in a wider range of eye diseases. Clinical trials are needed to confirm the efficacy of these treatment approaches in humans, but the results suggest that a simple approach such as targeting gut bacteria could have potentially life-changing effects.,
Autorin: Celina Prade
Quelle: DOI: 10.1016/j.cell.2024.01.040
Digital patient education in ophthalmology
Patients are informed about the expected results, advantages and disadvantages of surgical procedures during a medical consultation. Due to a lack of time, ambiguities can arise here. If patients' questions are not answered adequately, this quickly leads to anxiety and reduces compliance with pre- and post-operative care.
To solve these and other problems, many practices are turning to proactive virtual patient education (VPE) to complement face-to-face consultations. VPE allows practices to communicate information about the procedure or treatment plan to their patients via digital channels such as email or SMS. In this way, patients gain a better understanding of the surgical process and can better engage with the treatment. More and more eye surgery centers are also taking advantage of this.
A growing trend for all types of informative learning is video. With the rise of social media apps such as Instagram and YouTube, videos have become a standard method of sharing information. The advantage of videos is that they explain complex topics using moving graphics, animations and other visual elements that can complement and clarify face-to-face consultations and printed literature. This makes videos the perfect medium for explaining surgical procedures such as cataract removal, lens replacement and LASIK. They can also be used to explain different eye conditions and their treatments, explain the risks and benefits of a procedure, give an overview of what to expect on the day of surgery and inform patients about care instructions before and after the procedure.
In addition to pre-recorded content, there is also the option of real-time consultation via video. Video calls via various platforms can be a helpful way for people in remote or rural areas to get information and ask questions without having to make multiple trips to the clinic.
The benefits of VPE are significant for patients and practices alike. Clearly communicated information leads to reduced anxiety, increased satisfaction and better adherence to treatment plans. This is particularly relevant for patients in remote areas, who can be relieved of multiple clinic visits through VPE tools. For doctors, VPE means more efficient working practices, increased patient engagement and improved outcomes through increased patient compliance.
In addition to the benefits for patient education, VPE is also an effective marketing tool. Targeted information about treatments can appeal to potential patients and reduce anxiety. Practices can draw attention to their wider range of services through targeted cross-selling.
Overall, it is clear that VPE not only increases patient satisfaction, but also promotes the efficiency of practices and supports business growth. The combination of different tools and media enables comprehensive and effective communication that offers a wide range of benefits for both patients and practices.
Autorin: Celina Prade
Artificial intelligence in ophthalmology
AI-supported systems are already being used in many areastoday. In medicine artificial intelligence is already helping to evaluate diagnostic procedures and detect pathologies. The Cochrane Eyes and Vision Group has now conducted a study to investigate the extent to which AI has the potential to detectkeratoconus.
Keratoconus is a disease of the cornea, which becomes weakerand thinner with age, causing it to bulge out in a cone shape. The result is reduced vision. As the disease progresses, the cornea becomes so deformed that correction with glasses no longer offers a satisfactory solution.
According to the working group, progressive keratoconus is often only recognized too late. This is mainly due to the factthat the diagnosis has to be interpreted manually on an individual basis. The initial stage of keratoconus is thereforeoften not recognized during regular check-ups in primaryophthalmological care.
This raises the question of whether artificial intelligence can help to detect the first signs and prevent visual deteriorationthrough early treatment. The Cochrane working group asked itself this question and analyzed 63 studies that dealt with artificial intelligence and keratoconus. They found that artificial intelligence detects keratoconus almost perfectly(with a sensitivity of 98.6%).
However, this is in contrast to the results of the certainty of proof and evidence. According to the working group, the approach of the studies was not uniform, which led to difficulties in the evaluation. They suspect that the AI appearsto be more accurate than is actually the case.
In summary, it can be said that AI offers great potential to support medical diagnostics. However, further research is needed to determine the accuracy of AI, especially in the detection of specific ophthalmic conditions such as keratoconus.
Source: https://www.aerzteblatt.de/nachrichten/147947/Wie-genau-KI-einen-Keratokonus-erkennt
author: Celina Prade
Diabetic retinopathy: news from research
The University of Bristol in England has presented groundbreaking research findings that suggest a novel inhibitor could prevent the onset of microvascular diabetic complications, particularly eye and kidney disease. Previous treatments for patients with such complications failed to completely halt progression and often led to serious consequences such as blindness and kidney failure.
The research team focused on the protective lining of all blood vessels, known as the glycocalyx. In people with diabetes, this lining is often damaged. In experiments with two mouse models, the researchers were able to show that the development of diabetic eye and kidney disease can be halted if damage to the glycocalyx is prevented. This was achieved by using a heparanase inhibitor. Heparanase acts like a pair of scissors and damages the glycocalyx lining, but the inhibitors prevent this damage. The team has successfully developed a new class of these inhibitors that could prove to be promising drugs for treating patients.
Professor Rebecca Foster from Bristol Medical School emphasized the importance of the findings: "Our results are exciting as we have been able to show that a particular type of drug can prevent various diabetic complications, which is a global health problem for adults with diabetes."
Dr. Monica Gamez, research fellow at Bristol Medical School, added that the team is currently conducting research to prepare the novel class of inhibitors for clinical use. With more than 8% of the world's adult population suffering from diabetes, the researchers hope that their findings will benefit patients in the future. The development of this inhibitor could therefore make a significant contribution to improving the quality of life of millions of people worldwide.
author: Celina Prade
Source:: Ophthalmologische Nachrichten. https://biermann-medizin.de/diabetische-retinopathie-neuartiges-medikament-koennte-entwicklung-von-diabetischen-augen-und-nierenerkrankungen-stoppen/
Migraine and blood flow to the eye - is there a connection?
The results of a new study in the Journal of Head and Face Pain indicate a connection between migraine attacks with aura and the retina of the eye. The visual disturbances experienced by many migraine patients are therefore associated with circulatory disorders in the retina of the eye. Optical coherence tomography angiography makes it possible to record these disturbances, especially in migraine with aura compared to migraine without aura. The study of 37 patients with aura and 30 without aura showed that the "Vessel Flux Index" (VFI), a measure of recognizable vessels in optical coherence tomography angiography, was already 13% lower in patients with aura during the pain-free interval. In addition, during attacks, patients with aura showed more uniform boundaries of the recess. Interestingly, in patients with unilateral headache, blood flow in the eye on the same side as the headache was better during the attack than on the opposite side.
During the attack, both groups experienced a 7% decrease in VFI, a unit for recognizable vessels. Although retinal death does not usually occur, it is apparent that blood flow in patients with aura remains slightly worse than in healthy people even after the end of the pain attack. These results provide a plausible explanation for the visual disturbances that occur before the onset of the headache in patients with aura. However, the suitability of this examination as a biomarker for estimating the severity of migraine and the need for therapeutic consequences should be investigated further.
Source: https://headachejournal.onlinelibrary.wiley.com/doi/10.1111/head.14654
author: Celina Prade
Progress in research - new therapy embraces new chances
A complete loss of sight is usually irreversible. Will it be possible to restore sight to blind people in the future?
Research into restoring sight in blind people has made significant progress. Botond Roska from the Institute of Molecular and Clinical Ophthalmology in Basel has developed a pioneering method to restore the function of defective sensory cells in the retina. By genetically modifying retinal cells, Roska was able to introduce genes in a targeted manner using harmless viruses and thus restore vision in blind mice and human retinas. He has now been honoured with the Translational Neuroscience Prize from the Gertrud Reemtsma Foundation.
José-Alain Sahel from the Sorbonne University in Paris has also developed a gene therapy and light-enhancing glasses to treat patients with retinitis pigmentosa. This hereditary retinal disease, which affects over two million people worldwide, leads to a degenerative loss of sensory cells in the retina.
The researchers used a tiny green algae called Chlamydomonas reinhardtii, which consists of only one cell and has no eyes, but is nevertheless able to move towards the light thanks to light-sensitive proteins known as channelrhodopsins. These proteins are similar to the light-sensitive molecules in human sensory cells in the eye. By introducing the gene for such a channelrhodopsin into other cells, they were made sensitive to light, a technique called optogenetics, which is also used in other areas of neuroscience.
In a clinical study, the researchers treated a patient with retinitis pigmentosa who had gone blind over a decade ago. They introduced the gene for the light-sensitive molecule Chrimson R into the patient's retina, making retinal ganglion cells sensitive to light. Although these nerve cells cannot normally receive optical signals, it took almost five months before they produced the protein permanently and the patient was able to perceive his first visual impressions.
The researchers also developed light-amplifying glasses that record the environment with a camera, convert signals into yellow-orange light and transmit them to the patient's retina in real time. After seven months of intensive training, the patient was able to localise, touch and count objects in front of his eyes. Measurements of brain activity confirmed the activation of the visual centre in the brain during these activities.
Overall, the results show promising progress in optogenetic therapy for the partial restoration of vision in retinitis pigmentosa. However, further studies and optimisation are required before this treatment can be used in clinics. The Translational Neuroscience Award recognises the pioneering contributions of Botond Roska and José-Alain Sahel in this field.
You can find the entire article on the website of the Max Planck Institute: https://www.mpg.de/20464495/translational-neuroscience-preis-roska-sahel
Autorin: Celina Prade
Sicca symptoms
Dry heating air and a lot of screen time lead to irritated and itchy eyes for many people, especially in winter. For some patients, dry eyes are even a chronic problem that severely restricts their quality of life.
For both short-term and long-term effects, over-the-counter solutions such as saline solutions in the form of eye drops should be used. You can get recommendations from your ophthalmologist as to which eye drops are particularly suitable for relieving itching. Contact lens wearers in particular should pay attention to the compatibility of the drops. Patients who drip more frequently during the day should choose preservative-free eye drops.
Moisturizing masks, humidifiers and eyelid wipes are also possible ways of moisturizing the eye. If these remedies are not effective, prescription therapies may be considered. Individuals can talk to their ophthalmologist about prescribing special contact lenses, individual ophthalmic treatments such as punctum plugs or intense pulsed light.
Cynthia Matossian, an ophthalmologist from the USA, points out in her article that most patients with dry eyes initially start treatment with artificial tears on their own. The task of ophthalmologists here is to educate patients about the correct choice of medication and hygiene and to monitor the improvement in symptoms.
Autorin: Celina Prade
Safe cataract operations: The femtosecond laser
The results of a new study on the safety of cataract surgery show that both femtosecond laser-assisted cataract surgery and standard surgery are both safe. The safety and efficacy of both methods were confirmed regardless of the surgical method chosen.
Cataract surgery, a common treatment for cataracts, was evaluated for intraoperative and postoperative complications and long-term effects. Both groups, with femtosecond laser-assisted cataract surgery and standard manual surgery, showed few complications. The measured values of visual acuity and refraction were almost within the normal range after an observation period of one to twelve months.
Femtosecond laser-assisted cataract surgery uses a laser for incision, capsule opening and lens fragmentation. A special interface stabilizes the eye and prevents movement, which facilitates the precise transmission of laser energy. The doctor performing the procedure analyzes the anterior segment of the eye, plans the incision and enables the correct placement of the artificial lens. The femtosecond laser generates pulses of highly focused infrared light with an ultra-short duration of between ten and 15 femtoseconds.
The study, commissioned by the Institute for Quality and Efficiency in Health Care (IQWiG), analyzed over 30 randomized controlled trials with more than 7,200 treated eyes of around 5,500 patients. It included short- and long-term outcomes such as visual acuity and vision-related quality of life. The results show no significant differences between the two methods, suggesting that both are equally effective and safe.
Overall, the study highlights the advances in eye surgery and provides valuable information for healthcare professionals and patients when deciding on the appropriate surgical method for cataract treatment.
Source: https://www.aerzteblatt.de/nachrichten/sw/augenheilkunde?s=&p=1&n=1&nid=148674
Pandemie der Myopie
In their paper "The Myopia Pandemic", Omid Kermani and Arthur B. Cummings look at two studies that have researched the current state of global myopia figures, as well as future developments and possible approaches to improvement. The findings of a working group of doctors and scientists, the AAO's Task Force on Myopia, analysed scientific literature and showed that myopia (from -0.50 diopters) will increase from 22.9% of the world's population in 2020 to 49.8% in 2050. They speak of a "myopia pandemic".
In addition to genetic predisposition, the reason for the pandemic lies primarily in extensive close-range activity, such as computer work. It has been found that myopia correlates with the level of education in a country and therefore also the average time spent reading and writing.
It is important to note that myopia also correlates positively with other eye diseases such as cataracts and glaucoma. Myopic refractive errors are therefore associated with an up to tenfold higher risk of retinal detachment.
Uncorrected myopia is therefore a major problem. Economic problems such as a high loss of productivity and social consequences such as the still high number of avoidable cases of blindness worldwide are some of the issues that play a decisive role in this context.
Optical, pharmaceutical and behavioural interventions can be approaches to combat the pandemic. Above all, however, emphasis should be placed on early childhood prevention. Children who spend a lot of time outdoors develop a shorter axial length on average and therefore a lower risk of myopia.
In their study, Bullimore et al. address the question of whether the potential benefits of various measures to slow the progression of myopia justify the potential risks of treatment. Unique to this study is the model that Bullimore et al. developed to compare the risks and benefits of vision correction interventions with the effects of not taking the interventions. Firstly, the risk of visual impairment was calculated as a function of the severity of myopia based on various patient data. The years that the patient has to live with the visual impairment were then compared with the years that could have been prevented by control measures.
Bullimore et al. came to the conclusion that the potential benefits of therapeutic myopia control outweigh the associated risks.
For example, even if long-term treatment with contact lenses is associated with a high risk of infection, the benefits of improving vision through this form of therapy outweigh the risk.
The need for further research into myopia and possible corrective measures is emphasised.
you can find the paper at publications.
Global ophthalmological care - approaches for optimizing quality in developing countries
Cataract extraction is the most common eye surgery worldwide, but offers lower success rates in resource-poor regions. A 2017 survey of 20 low- and middle-income countries found that only 36.7% of operable cataracts were successfully operated on. This emphasises the need for improved cataract surgery coverage.
To address this problem, an increase in the number of trained ophthalmologists is required. The accessibility and quality of treatment must be improved.
ORBIS International, an NGO dedicated to the prevention and treatment of blindness and visual impairment in developing countries in South East Asia, India, Latin America and Africa, has recognised this gap and offers training in surgical and simulated environments. Simulation training offers numerous advantages, such as a safe environment, coping with complications, a risk-free learning curve and interaction with various mentors.
Orbis offers simulation training in traditional simulation centres in partner hospitals as well as virtual training via Cybersight. Virtual simulation training allows local residents to collaborate with international experts via real-time video conferencing. Weekly lectures and practical exercises on surgical procedures are recorded and assessed by remote professors.
Montero, deputy director of Orbis, also emphasises the importance of validated assessment tools for simulations. These tools should be objective, reliable and applicable to the learning objectives. Orbis uses several assessment tools, including the Iowa Wet Lab exam and the Ophthalmic Simulated Surgical Competency Assessment Rubric.
Orbis has conducted successful projects such as Virtual Wet Lab Training in Manual Cataract Surgery and Virtual Remote Training in Advanced Phacoemulsification Skills. These projects have shown that virtual training can improve the skills of residents.
Training and simulation training are a step in the right direction. In order to sustainably improve the quality of ophthalmological treatment in developing countries in the future, the consistent implementation and further development of such ideas is essential.
The EVO ICL - an alternative for patients with thin corneas?
Since the EVO ICL from STAAR Surgical received FDA approval in April 2022, many patients have already benefited from it. The EVO ICL offers an alternative for patients with a high degree of myopia or thin corneas who are not suitable for LASIK or PRK. The EVO ICL is a further development of the ICL that has been established for many years. Thanks to so-called EDOF optics, the EVO ICL has greater depth of field and is therefore particularly suitable for middle-aged patients who find working at a computer or reading increasingly difficult.
Doctors emphasise that the EVO ICL offers the advantage of not having to perform a peripheral iridotomy, which improves patient comfort and simplifies the surgical procedure. They also report a lower pressure increase in the eye after surgery compared to previous ICL versions. Although some patients continue to complain about glare and halos, they are generally satisfied with the results.
Choosing the right size ICL is critical to the success of the procedure, and surgeons use advanced diagnostic techniques to predict the ideal size. Despite the success of the EVO ICL, doctors emphasise the importance of experience and recommend proceeding cautiously with initial cases until a safe sizing strategy has been developed. Overall, EVO ICL is considered a promising option for patients seeking an alternative vision correction method.
Read the testimonials of ophthalmic surgeons using the EVO ICL here.
Refractive surgery in children
With the current increase in myopia, the topic of refractive surgery in children and adolescents is becoming increasingly important. In expert circles, however, the underage patient group is often neglected. For this reason, Dr. Kermani conducted a survey among refractive surgery colleagues. The aim was to find out how often children and adolescents receive refractive surgery treatment, which operations are performed and what the treatment results are.
The following results were obtained:
- All surgeons are aware of and agree with the ethical and legal considerations involved in performing refractive surgery on children.
- Most surgeons have little experience in treating adolescents as they only treat this age group sporadically. Reports from more experienced surgeons are not published, so no further information is available.
- Surgeons agree that only pronounced visual defects and significant visual impairment or other medically relevant indications are presented.
- The most commonly practiced operations are LASIK, ICL implantation and PRK. This raises the question of whether procedures are also performed for cosmetic or comfort reasons
It should also be asked to what extent age is a factor in the safety of refractive surgery. No data is currently available on this. It is interesting to note that many surgeons stated that the overall treatment results for young adults and children were better than those for adults. It can therefore be concluded that there is currently too little data available to make a well-founded statement about the performance of refractive surgery on minors. The growing myopia figures show that there is a need to address the treatment of eye diseases in early childhood. As there is currently very little data on refractive surgery in children, no treatment guidelines can currently be derived from this. In individual cases, however, this data can help to make an individual treatment decision.
Click here to get to Dr. Kermani's presentation.
Lessons learned: strategies to avoid common pitfalls
Ophthalmology is constantly changing. At the end of the year, it's time to look at past experiences from the past year and use them for continuous improvement to provide the best possible patient care.
The article "Lessons learned: strategies to avoid common pitfalls" by Mitchell Weikert in the current issue of EyeWorld illustrates how the industry benefits from past experiences and improves its standards. One focus is on lessons learned in the context of cataract surgery, where renowned specialists such as Dr. Rom Kandavel, Dr. Mitra Nejad and Dr. Amandeep Rai, FRCSC, provide valuable insights into individualizing the optimal timing of the procedure. Particular attention will be paid to the concept of patient-centered care, which provides for tailored decision-making for each individual patient.
The impact of the COVID-19 pandemic on cataract treatments, including delayed surgery for more severe cases, is opening up important discussions about the timing of procedures, careful consideration of patient goals and setting appropriate expectations. In addition, experts focus on the importance of a reassuring and comfortable patient experience. Their comprehensive overview of risk factors for patient discomfort and practical recommendations for prevention and treatment emphasize the importance of positive and collaborative interactions between clinicians and patients.
It also emphasizes the importance of accurate health data collection. This task is becoming more challenging in the age of electronic health records, with patients having greater access to their own medical data. The authors not only highlight the most common causes of documentation errors, but also offer recommendations for minimizing errors and promoting collaborative processes that enable accurate data capture.
Overall, the current issue of EyeWorld reflects how ophthalmology is learning from experience and constantly evolving. With the insights gained, the industry hopes to be better equipped in the new year to successfully tackle future challenges.
Lessons learned: strategies to avoid common pitfalls
Today, around 1.1 billion people worldwide have to live with untreated vision loss. 43 million of these people are blind. The main cause of this is an untreated cataract. It is striking that around 90% of these people live in low- or middle-income countries. The article "A Force for Good in Global Eye Care" discusses the challenges and progress in the field of visual health in sub-Saharan Africa and the efforts of organisations such as the Community Eye Health Institute (CEHI) and the European Society of Cataract and Refractive Surgeons (ESCRS) to meet this need.
Despite advances over the last two decades, around 1.1 billion people worldwide still suffer from untreated vision loss, with cataracts being the main cause. The CEHI, founded by the University of Cape Town, has trained some 600 postgraduates since 2008 who are now involved in eye health research and development in Africa, the Middle East and Asia.
One focus of the CEHI is on surgical training, particularly in small incision cataract surgery. The introduction of a surgical skills training programme, including simulation training, aims to improve surgical outcomes. However, there are bottlenecks in training due to limited resources such as surgical microscopes and trainers. Another challenge is the shortage of specialised medical staff for follow-up care. In underserved areas in particular, patients do not receive professional medical care.
Cooperation with the ESCRS is crucial to overcoming these bottlenecks. The ESCRS supports the CEHI financially and provides experts who donate their time and expertise to train surgeons in African countries. The joint efforts aim to reduce the number of avoidable cases of blindness in the region.
Another supported programme is "Eyes of the World" in Mozambique, which focuses on building local capacity. It trains local professionals in the detection, referral and treatment of vision problems and aims to improve the quality of surgery through monitoring tools.
The challenges in the region lie not only in surgical training, but also in post-operative care and improving access to eye care in general. ESCRS also supports programmes in Ukraine and Jerusalem to address the global need for eye care.
In order to improve eye care in underserved areas and thus reduce the number of avoidable cases of blindness worldwide, teaching expertise is needed in addition to donations and financial support. CEHI's efforts focus not only on treatment, but also on training local medical and surgical professionals to provide a long-term solution to the need for eye care.
Today, around 1.1 billion people worldwide have to live with untreated vision loss. 43 million of these people are blind. The main cause of this is an untreated cataract. It is striking that around 90% of these people live in low- or middle-income countries. The article "A Force for Good in Global Eye Care" discusses the challenges and progress in the field of visual health in sub-Saharan Africa and the efforts of organisations such as the Community Eye Health Institute (CEHI) and the European Society of Cataract and Refractive Surgeons (ESCRS) to meet this need.
Read the whole article here
Global Prevalence of Myopia and High Myopia and Temporal Trends from 2000 through 2050
In a new study "Global Prevalence of Myopia and High Myopia and Temporal Trends from 2000 through 2050", Holden et al. found that the number of myopia patients worldwide will continue to increase in the future. While 1406 million people worldwide had to live with myopia in 2000, this figure had already risen to 1950 million by 2010. According to projections, this figure is expected to rise to 3361 million people by 2023. What is the reason for the drastic increase in the number of people affected?
The expected increase in myopia and high myopia is largely considered to be the result of environmental factors, particularly lifestyle changes. These include less time spent outdoors and increased proximity activities, particularly in the workplace. Although genetic predisposition also appears to play a role, it alone cannot explain the observed trends over a short period of time. Environmental factors could include so-called high-pressure education systems, especially at a very young age in countries such as Singapore, Korea, Taiwan and China, as well as excessive use of electronic devices in close proximity. Other proposed causes include lighting conditions, which may be directly related to time spent outdoors. Peripheral hyperopia of the myopic eye, both corrected and uncorrected, is thought to promote axial hyperopia.
Holden et al. emphasise that if the findings and projections are correct, they will have a significant impact on the planning of comprehensive eye care services worldwide. By 2050, almost 1 billion people with high myopia will need to be treated, 7.5 times more than in 2000, and they emphasise the great benefit of a versatile and early myopia control system to mitigate this scenario.
MEACO-MIOC 2023
The MEACO-MIOC Congress is a prestigious event focussing on ophthalmology in the Middle East and Africa. The congress brings together leading professionals, researchers, practitioners and industry experts in ophthalmology to discuss the latest developments, research findings and innovations in the field.
During this 3-day congress, over 100 experts will present various publications, studies and other research findings. Dr Kermani will present the clinical results of patients who have decided to implant an IOL after laser treatment. This additional lens allows for fine corrections to achieve optimal vision. During this presentation, Dr Kermani also highlights the challenges associated with this treatment. Often, traditional biometric formulas are not adapted for pre-treated eyes, and options for possible follow-up treatments, such as corneal correction, are limited.
Dr Kermani chaired an event organised by the American Academy of Ophthalmology together with MEACO, which consisted of three parts, each with three speakers.
The main topics were: "The transition to refractive surgery", "No Capsule- no problem" (the possibilities of performing vision correction without a capsule) and the co-morbidities of cataract surgery. Dr Kermani gave a lecture on "Custom Made Anterior Chambers IOL - Case Reports". You can find the lecture as PDF here.
Das erste transplantierte Auge
In his new article "Sehr her!" Jörg Zittlau reports on Aaron James, who survived a serious
electrical accident. He lost parts of his left arm, his nose, lips, parts of his chin and his left
eye. Under the direction of Dr Eduardo Rodriguez at NYU Langone Health in New York City,
he received the world's first facial transplant with a complete eye during a 21-hour procedure
in May 2023.
The donor eye was transferred along with the eye socket and surrounding
tissues, connecting blood vessels and the optic nerve.
The hope was that visual signals could be transmitted from the new eye to the brain. Despite
intensive observation, there is no evidence to date that nerve signals from the transplanted eye
reach the visual cortex. Although the eye has not been rejected and shows some functional
aspects, there is no clear evidence of visual perception.
The controversy in professional circles centres on the question of whether the transplantation
is merely a cosmetic success or represents a significant advance in medicine. Some argue that
the regeneration of complex nerve connections, particularly in the optic nerve, is not
sufficiently realistic to restore immediate vision. Muscle functions, particularly the control of
eye movement, are also critical to vision.
Ophthalmologist Dr Omid Kermani from the Artemis Eye Clinic in Cologne reports on
controversial discussions. Some see transplantation as a door opener for new areas of
research, while others regard it as a mere spectacle that raises exaggerated hopes. Kermani
emphasises that the restoration of functional nerve cords, especially in the optic nerve, is a
complex challenge
Many experts therefore see transplantation as an important step for science, but are sceptical
about the brain's ability to interpret the signals from the transplanted eye. Further research is
needed to clarify the long-term potential of eye transplants. Future developments could
include gene therapy and innovative approaches to bypass damaged neural pathways.
Quelle: Zittau, Jörg. Sehr her! (2023). Welt am Sonntag. Ausgabe 47. S. 63.
Refractive surgery - Risks and benefits
Zittlau describes the challenges associated with visual aids such as glasses or contact lenses. Everyone who relies on visual aids is probably familiar with foggy glasses or itchy eyes. Laser eye surgery is therefore the long-awaited solution for many patients.
In his article, Zittlau addresses the recent debate about the risks and side effects of refractive surgery in the USA. According to Thomas Kohnen, Director of the Department of Ophthalmology at Frankfurt University Hospital, refractive surgery in Germany is much more advanced than in the USA. A separate commission has been set up to assess the safety of the current procedures, LASIK, Femot-LASIK and the SMILE procedure. The Komission Refraktive Chirurgie (KRC) sets restrictions, for example, on the maximum dioptre values or the minimum thickness of the cornea. Kohnen sees this as the reason for the increasingly loud debate in the USA about the risks of laser eye treatment. Patients with chronically dry eyes or very thin corneas who would be excluded from the procedure in Germany are also lasered there. As a patient, you should therefore realise that you may also be rejected by an eye clinic if your own eyes are not suitable for laser treatment. The high safety standards are reflected in the results: Dr Kermani's re-treatment rate for short-sighted patients is less than 5 per cent in the first 15 years. It is important to realise that every result can always change. "The eye is a living organ that changes throughout life," Dr Kermani is quoted as saying in the article. If this is the case, there is also the option of using an implantable contact lens.
Source: Zittau, Jörg. Das kann ins Auge gehen. (2023). Welt am Sonntag. Ausgabe 41. S. 61.
Femto-LASIK Sets High Bar for Myopic Correction
That's the message from Miguel A. Teus, PhD, professor of ophthalmology in Madrid, at the ESCRS Winter Meeting in Vilamoura, Portugal, 2023. He addresses the comparison between femtosecond LASIK (FS-LASIK) and lens extrusion procedures, such as the SMILE procedure.
The SMILE procedure uses a high-precision femtosecond laser to change the shape of the cornea. A lens, called a lentricle, is formed within the cornea. The advantage of the SMILE procedure is the avoidance of complications, fewer dry eyes, and increased biomechanical stability because more fibers of the cornea are preserved. However, the symptomatology of dry eye in particular is not clearly provable, Dr. Teus said. Most studies conclude that nerve regeneration and corneal sensitivity develop about the same with both procedures.
The major disadvantage of the SMILE procedure over excimer laser correction is the greater loss of corneal tissue in low myopia. To avoid damage to the lens created by the SMILE procedure, the optical zone must be enlarged and a thicker lens thickness must be set. Consequently, more corneal tissue is removed than with excimer laser surgery, especially for lower myopias.
You can find the whole article here: https://www.escrs.org/eurotimes-articles/femto-lasik-sets-high-bar-for-myopic-correction/
Phakic intraocular lenses - what are they?
Phakic intraocular lenses are artificial lenses that are implanted in the eye to correct various types of visual defects such as myopia. In contrast to so-called multifocal lenses, no lens replacement takes place here. The phakic intraocular lens is implanted in front of the eye's natural lens.
These phakic IOLs are used in particular for patients with extremely severe visual impairments that cannot be corrected by LASIK. Phakic IOLs can correct myopia of up to -23.5 diopters, hyperopia of up to +12 diopters and astigmatism of up to 6 diopters. In addition, IOLs also offer patients with particularly thin corneas the opportunity to correct their visual defect effectively and with long-term stability.
When choosing an IOL, there are various types to choose from, which differ in terms of shape and material composition. One example is the Artisan, the Artiflex or the ICL. Both are ultra-thin lenses that are inserted into the eye through a very thin access (2.0mm with ICL, 3,5mm with Artiflex und 5.0mm with Artisan) and fixed to the iris. The Artisan is rigid, while the Artiflex is made of soft material. The ICL is made of Collamer, which has proven to be particularly well tolerated. If you have astigmatism, you can also opt for the toric version of the Artisan.
When choosing an IOL, there are various types to choose from, which differ in terms of shape and material composition. One example is the Artisan, the Artiflex or the ICL. Both are ultra-thin lenses that are inserted into the eye through a very thin access (approx. 3-5 mm) and fixed to the iris. The Artisan is rigid, while the Artiflex is made of soft material. The ICL is made of Collamer, which has proven to be particularly well tolerated. If the patient has astigmatism, the toric version of the Artisan can also be used.
In addition to the desire to be spectacle-free, phakic intraocular lenses are also used for patients diagnosed with keratectasia, a condition that leads to thinning and deformation of the cornea. Positive results have already been observed here in the past (Wagner & Sekundo, 2023).
Overall, studies show that phakic intraocular lenses are a promising option for the correction of visual defects such as myopia in suitable patients. With the continuous development of designs and technologies, the use of phakic intraocular lenses as a refractive surgical technique is expected to increase in the coming years.
author: Celina Prade
Sources:
- Alfonso et. Al. Posterior chamber collagen copolymer phakic intraocular lenses to correct myopia: Five-year follow-up. Alfonso, Baamonde, Fernández-Vega et al. 2011Journal of Cataract and Refractive Surgery
- Iatrogene Keratektasie nach refraktiver Chirurgie – Ursachen, Prophylaxe, Therapie. Wagner, Sekundo 2023 Klin Monbl Augenheilkd
- Advances in phakic intraocular lenses: indications, efficacy, safety, and new designs. Alió 2004 Current Opinion in Ophthalmology