EyeWorld is the official news magazine of the American Society of Cataract & Refractive Surgery.
Issue link: https://digital.eyeworld.org/i/78721
54 EWInternational January 2012 International outlook The correction of age-related focus The Latin American Society of Cataract T T his month's International outlook features a roundtable chaired by William De La Peña, M.D., chief executive officer of the Latin American Society of Cataract and Refractive Surgeons. He guides this distin- guished panel of experts in a discussion on how they use premium channel IOLs. Certain themes are universal, and the challenges we face meeting patient expec- tations with high technology IOLs are com- mon to surgeons around the world. Patient selection, patient education, and matching the best choice of IOL to the patient's needs are the common denominators of success. I hope you enjoy this enlightening discussion from our South American col- leagues on the art of using premium IOLs. John Vukich, M.D., international editor he ALACCSA-R Newsletter, the monthly journal of the Latin American Society of Cataract and Refractive Sur- geons, invited three Latin American surgeons experienced in IOL presbyopia-correction surgery to share their experiences. William De La Peña, M.D., CEO of ALACCSA-R, coordinated, and Enrique Suárez, M.D. (Venezuela), Edgardo Carreño, M.D. (Chile), and Virgilio Centurion, M.D., (Brazil) were the guests. Dr. De La Peña:What ancillary ophthalmological exams do you rou- tinely perform before implanting high technology IOLs for presbyopia correction? Dr. Suárez: A retina specialist exam, including optical coherence tomography (OCT) and infrared and fluorescence, corneal topography, and specular biomicroscopy. Dr. Carreño: Before implanting high technology IOLs for presbyopia correction, I routinely perform bio- metry and keratometry with an IOLMaster (Carl Zeiss Meditec, Dublin Calif.); keratometry, topogra- phy, aberrometry, and pupilometry with the iTrace (Tracey Technologies, Houston); keratometry and topogra- phy with the Pentacam (Oculus, Lynnwood, Wash.), including poste- rior corneal surface elevation; ker- atometry with an autorefractometer; endothelial count and macula and optic disc OCT. All these ancillary exams are aimed at optimizing re- fractive outcomes with these im- plants. Dr. Centurion: 1) Optical biometry or partial coherence interferometry with the IOLMaster; 2) Contour topography to verify the corneal surface; 3) Specular microscopy to verify endothelial integrity and predict corneal resistance, should any com- plication arise; 4) Potential visual acuity; if pos- itive, it is an indicator of macular health, if negative, we further evalu- ate the retinal condition; and 5) Central and peripheral retina evaluation by OCT and indirect oph- thalmoscopy. Dr. De La Peña: What is the role of low-grade corneal astigmatism (≤0.75) when high technology IOLs for presbyopia correction are pre- scribed? Dr. Suárez: In astigmatism <0.50 D, I perform the main corneal inci- sion in the meridian of the highest keratometric value or topographic curvature. For with-the-rule astigma- tism <0.75 D I prefer to implant aspheric IOLs. If it is >0.50 D against-the-rule, I prefer to implant toric IOLs (mono or multifocal). Dr. Carreño: Accumulated expe- rience after implanting a high number of advanced technology multifocal IOLs has shown me that low corneal astigmatism between 0.50 and 0.75 D may negatively in- fluence the patient's visual acuity. That is why I recommend toric mul- tifocal IOLs (AcrySof IQ ReSTOR Toric, Alcon, Fort Worth, Texas) for presbyopia correction in patients with corneal astigmatism ≥0.50 D. This has produced better visual acu- ity results and notoriously more sat- isfied patients. Dr. Centurion: The best thing would be to implant advanced technology IOLs for presbyopia cor- rection in non-astigmatic eyes. How- ever, statistics show that most of the eyes, ±62%, usually show some de- gree of corneal astigmatism requir- ing correction for good quality visual acuity. Toric multifocal IOLs for low- grade astigmatism have improved the chances for good results. I have not achieved consistent results, and I do not like performing corneal incisions for astigmatism correction (LRI, keratotomy). I think that it is not a good procedure be- cause of its low predictability. The femtosecond laser for corneal astig- matism correction may be more reli- able. Dr. De La Peña: How do you modify your surgical technique when implanting advanced technol- ogy IOLs for presbyopia correction? Dr. Suárez: I emphasize prevent- ing residual against-the-rule astigma- tism, especially with multifocal IOLs. Dr. Carreño: Since August 2011 we have been using a femtosecond lased guided by real-time imaging with incorporated OCT (LenSx, Alcon) in multifocal and toric IOL surgery. This technology permits a more precise, safer, and more repro- ducible procedure. This equipment performs a perfect capsulorhexis and corneal incisions; even though they are automated, they can be con- trolled and individualized by the surgeon and determine a better per- formance of these advanced tech- nology IOLs leading to better clinical results. Dr. Centurion: I am even more careful when performing capsulo- tomy; it should be central, continu- ous, and ±5.0-5.5 mm in diameter. The procedure should not have any complications when performed through a 2.2 mm corneal wound and astigmatically neutral. Both eyes should be operated on within 7 days. Dr. De La Peña: Posterior cap- sule opacification (PCO): • Does its incidence or prevalence increase with multifocal IOLs? • What are the specific risks of ad- vanced technology IOLs? • Is posterior capsulotomy per- formed routinely or with any modification? Dr. Suárez: • Its incidence is not higher, but it does induce more disturbances than monofocal IOLs. For that rea- son the incidence of posterior cap- sulotomy is higher with this type of IOL. • We may be more cautious while protecting the posterior capsule during surgery. • Wide, complete, and circular cap- sulotomy Dr. Carreño: I have not observed any significant difference in PCO with the ReSTOR or ReSTOR Toric as compared to the monofocal AcrySof IQ and AcrySof Toric. In my per- sonal practice the frequency of PCO with all these IOLs is under 2%. However, I have noticed a higher rate of posterior Nd-YAG laser capsu- lotomy in patients with multifocal IOLs that can be explained by a higher sensitivity of these IOLs to PCO, compromising visual acuity and leading to an earlier capsulo- tomy than in monofocal IOLs. Re- garding posterior capsulotomy technique, I think that it is safer to perform it slightly external to the lens rings in order to prevent any damage to the central, apodized dif- fractive area that might affect a pa- tient's vision. Dr. Centurion: I think that the rate of PCO is higher with multifocal