October 2012

 

INTERNATIONAL

 

Panel in Brazil discusses premium lenses


 

Participants

Miguel . Padilha, M.D.

Miguel . Padilha, M.D., is director, Brazilian College of Surgeons, and director, MPOftalmo Excelncia em Oftalmologia, Rio de Janeiro

Fbio Casanova, M.D.

Fbio Casanova, M.D., completed his residency and Ph.D. at Federal University of So Paulo, So Paulo, and his post-doctorate at Harvard University

Ramon Ghanem, M.D.

Ramon Ghanem, M.D., director, Cornea and Refractive Surgery Department, Sadalla Amin Ghanem Eye Hospital, Joinville, Santa Catarina, Brazil

Walton Nos, M.D.

Walton Nos, M.D., is professor, Federal University of So Paulo

Eduardo Soriano, M.D.

Eduardo Soriano, M.D., is staff member, Cataract Service, Federal University of So Paulo

Fernando Trindade, M.D.

Fernando Trindade, M.D., is director, Canado-Trindade Eye Institute, Belo Horizonte, Minas Gerais, Brazil

Wagner Zacharias, M.D.

Wagner Zacharias, M.D., is director, Centro de Cirurgia Ocular Jardins, So Paulo

 
Premium IOLs represent an evolution in technology. We have noticed this progress in the last 10-20 years. Over time, the new technology becomes the standard

Fbio Casanova, M.D.

Patients want the results they paid for. I hope this technology improves to provide better and more reproducible results

Ramon Ghanem, M.D.

The use of toric lenses has gained widespread acceptance due to their unequivocal excellent outcomes. Industry provides us with some models, and indications are expanding

Fernando Trindade, M.D.

Most patients tolerate small misalignments; otherwise, it is important to re-evaluate the whole process before repositioning the IOL surgically

Eduardo Soriano, M.D.

Dr. Padilha: In your personal experience, with what kinds of premium IOLs have you accomplished the best results?

Dr. Zacharias: A premium IOL isa relative concept and can offer something more than correcting the spherical refractive error. Nowadays, I'm having good results with both toric and multifocal diffractive IOLs.

Dr. Ghanem: I agree with Dr. Zacharias'comments.My best results are with total diffractive and diffractive/refractive multifocal IOLs, toric IOLs, and the combination of both technologies.

Dr. Soriano: Personally, I do not like the term "premium." It carries a strong connotation of marketing, implying that the patient will receive a "plus" or a "prize." This devalues conventional lenses, which are ideal for most occasions. In my view, it is important that physicians and patients understand that there are different types of lenses and the choice can be somewhat customized. The lenses that I have the best results with are the toric ones.

Dr. Casanova: For me, premium IOLs represent an evolution in technology. We have noticed this progress in the last 10-20 years. Over time, the new technology becomes the standard. We expect cheaper and higher quality products in all customer segments, and this is not different for the IOL market. I have excellent results with both diffractive multifocal and toric IOLs, as well as a combination of both technologies.

Dr. Padilha: What situations do not indicate multifocal lenses? Explain the reasons for not implanting refractive or diffractive lenses in patients who come to your office asking for them.

Dr. Zacharias: The candidate for a multifocal IOL needs to fill some basic requirementshaving a normal ophthalmic examination, a good corneal surface, regular astigmatism, a normal retina examination, and a normal optic nerve with good visual potential. Furthermore, the patient needs to understand the way the lens works and the limitations it has, such as halos at night, reduced contrast sensitivity with difficulty to read in dim light, and poor performance at intermediate distance. Some patients are not candidates for a multifocal despite their desire to have one.

Dr. Ghanem: Patients who have impairment of visual acuity due to systemic or ocular pathology with the exception of lens opacity are not good candidates. Most common causes for not indicating multifocal IOLs in my office include macular problems (age-related macular degeneration and epiretinal membranes) and corneal disorders (moderate and severe dry eye and irregular astigmatism).

Dr. Trindade: As we all know, multifocal IOL implantation should ideally be done in normal eyes. So a common pathology such as dry eye, glaucoma, macular degeneration, or cases of previous refractive surgery should be carefully analyzed before indicating a multifocal. With regard to refractive lens exchange, I never indicate multifocal implantation for emmetropic presbyopes. Because of contrast sensitivity reduction it is better to implant multifocals in patients who have an existing contrast sensitivity deficit from their cataract. Also, I avoid multifocal implantation in patients who work in low-contrast situations, such as professional night drivers, cinephiles, radiology technicians, and pilots. Macular pathology and optic neuropathies that inherently diminish contrast sensitivity are important contraindications.

Dr. Soriano: My indications for multifocal IOLs have diminished considerably. Initially, I was excited about the opportunity to correct pseudophakic presbyopia, but after seeing several patients dissatisfied with the visual quality obtained, my option remains monovision in some patients. As discussed above, the implant conditions for multifocal IOLs, despite being extended lately, must be restricted. It also should be taken into consideration the possible loss of visual potential that patients will present in the future because many will develop ARMD or diabetic maculopathy, etc.

Still, it's hard to know, even obeying the restrictions of use, which patients will adapt to having two images focused within the eye. Even explaining beforehand, many do not understand what to expect.

Dr. Nos: Exclusion criteria for me include patients who already had cataract surgery with monofocal lens implantation, irregular or abnormal corneas, severe dry eye, macular degeneration, advanced glaucoma, or any person with low visual potential.

Dr. Casanova: I am very satisfied with the results of diffractive multifocal IOLs. Besides these reasons mentioned by my colleagues, I would like to include the personal profile: patients with high expectations, extreme perfectionists, people requiring great night vision, or who have perfect near vision. I can remember some situations where I faced the perfect eye in the wrong patient. In one of them, a doctor with moderate hyperopia returned to my office four times to discuss a multifocal or aspherical monofocal IOL. He complained about some halos from the red indicator light while the TV was turned off. He was definitely not a good candidate. Also, I have reconsidered my indication in an overweight patient who uses computers for many hours a day after having operated on a patient successfully, revealing J1 as uncorrected near vision, but who could not adjust the distance of the monitor as I had suggested due to her obesity. She was not able to approximate the table.

Dr. Padilha: Do you have experience with accommodative intraocular lenses? Which IOL? If so, please give us the average of monofocal, multifocal, and accommodative IOLs you implant on a monthly basis. If not, why don't you implant accommodative IOLs at the present time? Are you planning to implant this kind of IOL in the near future?

Dr. Soriano: Yes, [I have implanted] the old C&C AT45, which was the initial version of the Crystalens (Bausch + Lomb, Rochester, N.Y.) that basically did not change over time. Routinely, 100% of the lenses I use are monofocal. Considering the accommodative lenses, the problem is that the available lenses do not accommodate at all. There is no evidence that this happens. What confuses this is the pseudoaccommodation that is present in any lens. I do not believe in the near future we will have a truly accommodating lens.

Dr. Zacharias: I don't have experience with accommodative IOLs, and I don't plan to implant them in the near future. My results with diffractive IOLs are superb and improving with time. For me, accommodative IOLs seem to lose effect over time, working as a monofocal after a while, which is the reason they preserve the contrast sensitivity when compared to multifocal IOLs.

Dr. Ghanem: I am currently implanting multifocal IOLs in about 30% of my patients. It could be more than 50% if financial issues were not a problem. At our hospital, we have implanted accommodative IOLs in the past, but due to inconsistent results, we are not implanting them anymore. Patients want the results they paid for. I hope this technology improves to provide better and more reproducible results.

Dr. Trindade: I am not yet convinced that current accommodative IOLs, regardless of their mechanism of action, truly restore active accommodation to a significant level, as they are touted to. It is important to point out that pseudoaccommodation properties such as increased depth of focus in senile miosis, for instance, mild monovision, and myopic astigmatism are common situations, isolated or combined, that enhance near vision function, rendering many patients even with a standard monofocal IOL glasses-free. Another drawback of the current accommodative lenses is the larger incision length necessary for their implantation. In my mind, accommodative IOLs are still an idealized concept but hopefully, in the not-too-distant future, the industry will provide us with a good product that will eventually replace multifocals.

Dr. Nos: We have had some experience with so-called accommodative lens. Unfortunately, in our experience, none of the three evolution models had enough accommodative power to allow true near vision, instead acting more as a monofocal lens. We have consequently focused on diffractive multifocal lenses with excellent results.

Dr. Casanova: After reviewing how the current technology works, I don't feel stimulated to implant accommodative IOLs. Possibly, in the near future, new designs and new concepts will offer better results. For now, I have used diffractive multifocal IOLs and monovision as options for presbyopic correction. The former are responsible for at least 50-60% of my practice. After combination of multifocal and toric technologies on the same platform, my percentage of patients receiving multifocals has increased.

Dr. Padilha: Do you feel premium IOLs are growing in Brazil? If your perception is that is not true, why do most of the Brazilian eye surgeons still prefer standard IOLs instead of premium IOLs? Dr. Zacharias: Certainly the number of premium IOL implantations is growing in Brazil, and it will increase over time because the patients are becoming more informed and confident with this technology, and even asking for this kind of lens. The reason why some eye surgeons still prefer standard IOLs is because they are not confident with their own results and don't want to risk them with such an expensive lens. The need for premium biometry and premium surgery makes them reluctant to adopt these special lenses.

Dr. Ghanem: I completely agree with Dr. Zacharias.

Dr. Trindade: Premium IOL implantation is growing everywhere, and the cost of the lens is funded by the patient in many countries, including Brazil. I think patient cost is the major reason that limits wider acceptance of premium IOLs over the standard lens. Also, it is well established that all presbyopia treatments involve a visual compromise of one sort or another, and most likely, surgeons who have not yet adopted premium lenses in their practices are in their comfort zone and satisfied with their results.

Dr. Soriano: I believe that is growing as a function of improving the economic condition of the country. Also, there is always a learning curve with the use of new lenses, leading to a time of "maturation." On the other hand, after the euphoria with the launching of the new lenses, there is an adjustment, where the real results begin to appear and surgeons choose the lenses that they trust. As I mentioned before, conventional lenses are suitable for most patients and many, like me, do not believe that visual quality is the price to be paid for independence from glasses.

Dr. Nos: The number of premium IOLs is growing fast in Brazil, especially the toric aspheric lenses and the multifocal diffractive toric. As the inclusion criteria for the multifocal is very restricted, most of the patients either do not qualify for those types of lenses, or lens selection is limited by patient choice and price.

Dr. Casanova: For sure, it's growing in Brazil as our economy is getting better. These premium IOLs mean additional costs for the patients. Besides, many doctors do not migrate to diffractive multifocals because they have good results with monofocal IOLs and do not want to take risks, have no access to more precise biometry, and because of the learning curve (getting used to chair time, handling the patient profile, self-assurance with a new technology, and choosing a good candidate).

Dr. Padilha: I think all of us agree that toric lenses are here to stay. But what is your main concern when planning to implant a toric IOL?

Dr. Soriano: An important challenge, in my view, is to implant the lens exactly in the planned axis. This process includes two steps: a) marking precisely the meridian of insertion, since the markers have some degree of inaccuracy, and b) positioning the lens at the planned axis at the end of surgery. However, there is still some imprecision in the determination of the power and axis of astigmatism. This can occur especially in corneas with astigmatism less regular and symmetrical.

Although the toric lens corrects corneal astigmatism, the observation of the relationship between the keratometry and the patient's refraction enters in the rationale of the use of toric lenses. It helps in the understanding of the refractive state of the eye, pointing to the role that the cornea and other elements such as the lens and the retina could play.

Dr. Trindade: The use of toric lenses has gained widespread acceptance due to their unequivocal excellent outcomes. Industry provides us with some models, and indications are expanding. My preference is to rely on toric lenses for patients with more than 1 D of regular corneal astigmatism. Accurate IOL power calculation, correct alignment of the lens, and post-op rotational stability are the main issues.

Dr. Ghanem: Placing it in the right axis is the main issue with this IOL. Usually I combine the information from various devices, including the IOLMaster (Carl Zeiss Meditec, Jena, Germany), topography, Galilei (Zeimer, Port, Switzerland), and automated keratometry. The IOLMaster provides central corneal (2.5 mm) power and axis, thus being my main guide. In patients with regular astigmatism it is usually easy to determine the right axis. In keratoconus eyes, however, it may not always be the case. Usually I draw a line through the middle of the skewed axes on the topography map to find the steepest meridian. I also combine information from the IOLMaster. I think toric IOLs are an excellent indication for cataract patients with keratoconus up to grade 3, when the patient is not a rigid contact lens user and is not likely to require a corneal transplant in the future.

Dr. Zacharias: The evaluation of the corneal power and axis of astigmatism are our main concern in planning a toric IOL. It is common to have different results from different devices, making it difficult to decide which to adopt. Despite the toricity, the power of the lens can be decided easily and the surgical axis to be implanted is shown by the calculator with good precision.

Dr. Nos: If we have regular astigmatism with normal topography, our main concern is ensuring proper lens alignment. This is even more important with higher-power toric lenses because even a few degrees could have a significant effect on the refractive outcome. If the cornea has had previous surgery and the topography is not regular, we need to pay special attention to the power and cylinder axis. We do not use simulated keratometry values to get the cylinder axis and power in these cases.

Dr. Casanova: Toric IOLs should be implanted in patients with regular corneal astigmatism. Defining the correct axis is the main issue. I also compare different devices with focus in corneal topography. If the keratometry is not matching, I check the corneal image at the topography. If the image quality is not good or inconsistent, the exam must be repeated. I personally perform the ocular biometry and IOL power calculation for my all cases. I can evaluate the tear film and consistency of measurements. Blepharitis and dry eye can frequently change these measurements. On the day of surgery, I mark the cornea using the slit lamp and enhance the marks in the OR. At the end of the surgery, the OVD removal is made with the toric IOL rotated a little bit counterclockwise. I always remove all of the viscoelastic from behind the lens, making it less likely to rotate. When finishing the case, double check the axis position comparing the paper and the image of the video screen or microscope.

Dr. Padilha: When managing toric lenses, what kind of special care do you take to mark the right axis? If you notice post-op that the IOL is not well centered or not at the right position, how do you fix the problem?

Dr. Ghanem: I mark the right axis directly at the slit lamp with an insulin needle. I scrape the corneal epithelium in the 6-7 mm zone along the axis of implantation and near the limbus in the axis of the main incision according to the calculator. With the patient under the microscope I just paint the markings with a gentian blue pen. This way, there is no need to use additional alignment instruments intraoperatively.

Dr. Zacharias: After trying different devices to mark the axis, I go back to the pendulum tomark the 6 o'clock point with the patient seated. To avoid fading of the mark, I ask the patient to sit at the slit lamp, then I scrap the point with an insulin needle and paint it with a methylene blue pen. This way, the mark remains visible during the surgery to guide the axis gauge.

Post-op, if the vision isn't as good as I expect it to be, I submit the patient to a refractive exam and dilate his pupils to examine him at the slit lamp and confirm if the axis is well positioned, comparing with the pre-op plan. If the lens is out of axis, I take the patient to the OR and rotate the lens to the right position easily, just with a Lester hook through a paracentesis under topical anesthesia.

Dr. Trindade: Before surgery, with the patient sitting upright at the slit lamp, I place reference marks, at the periphery of the cornea, on each side of the 0-180 degree meridian. There are many ways to make these reference marks, varying from surgeon to surgeon. If the patient happens to be unhappy with the surgical outcome, because of improper alignment of the toric lens, I would take him/her back to the operating room, as soon as possible, to rotate the lens back into the correct position, with OVD assistance.

Dr. Soriano: I like to use a bubble level marker and a speculum to determine the meridians of 3 and 9 o'clock, while the patient is sitting, before sedation or a block. Then intraoperatively, I use a gauge and a pen to mark the meridians of the lens and the incision. An important detail is that the marks are aligned with the visual axis/center of the cornea. It is also good to avoid using too much anesthetic eye drop to reduce the risk of epithelial injury, as well as using viscoelastic substance in the cornea only after marking. Most patients tolerate small misalignments; otherwise, it is important to re-evaluate the whole process before repositioning the IOL surgically, trying to not wait too long to prevent fibrosis of haptics to hinder the release of the lens.

Dr. Nos: I use a pendulum corneal marker to mark the patient while upright, in orderto compensate for cyclotorsion. The lens axis mark is made after the lens implantation with the toric axis marker, then the lens is aligned with the marks.

If we note any misalignment in the post-op period, which in our experience has been very rare, we can easily rotate the lens with a Sinskey hook under topical anesthesia if the rotation is visually significant.

Dr. Casanova: I mark the corneal astigmatism axis and the placement of the corneal incision at the slit lamp according to the toric IOL calculator. I do not use reference marks at 180 degrees because I do not use any other device to mark in the OR. Marking at the slit lamp avoids ocular cyclotorsion and allows me to confirm the correct corneal axis using the angle marker. In the OR, theses marks are enhanced under the microscope. I use a sharp point pen to avoid large marks that can cause mild misalignment. The point must be positioned perpendicularly to the cornea to avoid blurring. I have never performed a surgical reintervention for toric IOL repositioning. These lenses have a great stability in the capsular bag. However, if necessary, it should not be difficult. After injecting viscoelastic inside the bag, the IOL can be easily rotated using a Lester hook to be centered or placed on the right axis.

Editors' note: The physicians have no financial interests related to this article.

Contact information

Casanova: fhccasanova@uol.com.br
Ghanem: ramonghanem@gmail.com
Nos: wnose@me.com
Padilha: mpadilha@domain.com.br
Soriano: dusoriano@gmail.com
Trindade: fernandotrindade@mac.com
Zacharias: wzacharias@terra.com.br

Related articles:

The ethics of premium IOLs by Bonnie An Henderson, M.D., cataract editor

Talking finances with premium IOL patients by Faith A. Hayden EyeWorld Staff Writer

Evaluating patients for premium IOLs by Enette Ngoei EyeWorld Contributing Editor

Blepharitis and premium IOL patients by Elizabeth A. Davis, M.D.

Panel in Brazil discusses premium lenses Panel in Brazil discusses premium lenses
Ophthalmology News - EyeWorld Magazine
283 110
283 110
,
2017-03-09T11:27:18Z
True, 10