EyeWorld India December 2017 Issue

Spoiled for choice with toric presbyopic IOLs by Stefanie Petrou Binder, MD EyeWorld Contributing Writer Toric presbyopic IOLs combine best of modern IOL technologies to correct astigmatism, presbyopia A ccording to the 2016 ASCRS Clinical Survey, 1 the most common proce- dures used among ASCRS members to manage astigmatism in a patient highly motivated to receive a presbyopia-correcting IOL with 0.75 D of cylinder are on-axis incisions, manual limbal relaxing incisions (LRI), astig- matic keratotomy (AK), or femto- second laser AKs and LRIs. At the tipping point of 1.25 D cylinder, however, physicians prefer toric IOLs. Fortunately, surgeons now have several IOL options to meet the needs of presbyopic patients with visually relevant cylinder. According to Sumit “Sam” Garg, MD , Gavin Herbert Eye Institute, University of California, Irvine, California, who spoke at the 2017 ASCRS•ASOA Symposi- um & Congress in a session called “Pairing Astigmatism Patients with the Optimal Technology: What Would You Do?” surgeons have three viable IOLs to choose from that combine presbyopic and astigmatism corrections: the Trulign (Bausch + Lomb, Bridge- water, New Jersey), the Symfony Toric (Johnson & Johnson Vision, Santa Ana, California), and the AcrySof IQ ReSTOR Toric (Alcon, Fort Worth, Texas). Options make choices more complicated “What do more and better options mean for us?” Dr. Garg asked. “It means that things are more complicated. There are more con- siderations and more chair time. Looking at the difference between a standard toric and presbyopia- correcting toric IOL, there are a couple of considerations. For both, you need regular astigma- tism and an optimized ocular surface. Standard toric IOLs gener- ally cause less glare and dyspho- topsia, while you may need to tell patients who are interested in presbyopia-correcting toric IOLs that they can have some glare and dysphotopsia, like with the Symfony and somewhat less with the Trulign. Standard toric lenses are good, reasonable lenses for people with glaucoma, diabetes, and macular pathology, as long as there is still visual potential there. However, in patients with glaucoma with visual field de- fects, active diabetic retinopathy, or macular pathology, you want to steer away from the Symfony or AcrySof IQ ReSTOR platforms, but you could consider the Trulign. It used to be that when we talked to patients about these lenses, toric lenses did not equal multifo- cal or extended depth of focus, but now they do—or they can. I think that’s very exciting for our patients because it opens up a lot more options.” The effects of astigmatism on lens performance is a topic worthy of further exploration. In a recent prospective, comparative, interventional study 2 that investi- gated the impact of induced astig- matism with four different types of multifocal lenses in 80 eyes, including the AcrySof IQ ReSTOR +2.5 D (20 eyes), AcrySof IQ ReSTOR +3.0 D (20 eyes), AcrySof IQ PanOptix (20 eyes), and the Symfony ZRX00 (20 eyes), investi- gators found that the differences in IOLs with regard to the impact of the cylinder sign and axis on visual acuity and patient satisfac- tion were not significant. The PanOptix IOL was most affected by the induced astigmatism with respect to patient dissatisfaction and visual acuity. The highest tolerance to the astigmatic distor- tion and blurriness induced with a –1.50 D cylinder was obtained with the Symfony IOL. The study revealed that the simulated residu- al cylinders after the implantation of the Symfony IOL up to 1.0 D had a very mild and not clinically relevant impact on visual acuity and patient satisfaction. It showed that the extended range of vi- sion IOL had better tolerance to unexpected postoperative residual errors than diffractive bifocal and trifocal IOLs. Dr. Garg said it is the sur- geon’s job to figure out which IOL is right for each patient, in light of the wealth of informa- tion available from this and other studies. “What I am trying to highlight here is that you want to nail your options. The further you get away from being on target, the less happy the patient is. Some lenses are more sensitive than others depending on whether the patient has with- or against-the- rule astigmatism. Against-the-rule tends to be less tolerant and with- the-rule a little more tolerant. We also need to consider posterior corneal astigmatism. With presby- opic correcting lenses in general, we have to nail the astigmatism, and having a toric platform helps us in that regard,” he said. Getting the process right Dr. Garg presented the case of a patient with Symfony toric IOLs bilaterally. The patient’s right eye was dominant, and Dr. Garg planned a Symfony ZXR00 non-toric 15.5 IOL. For the left, non-dominant eye, he planned a Symfony ZXT225 toric 17.0. He aimed for just a touch of myopia, orienting the IOL on the steep corneal axis. The right eye was uncompli- cated, but Dr. Garg’s aberrometry recommended a ZXT150 15.5, to correct a small amount of astig- matism, which he oriented at 20 degrees. The ORA measured roughly 1.1 D at 20 degrees, and he achieved 20/20 uncorrected distance visual acuity and uncor- rected J3 reading. The patient’s left eye was also uncomplicated. Dr. Garg oriented the ZXT225 17.5 at 160 degrees. The patient achieved an uncorrected distance visual acuity of 20/40 and uncor- rected J2 near, but complained of slightly waxy vision. Dr. Garg noted a disconnect between the patient’s uncorrected visual acuity and the manifest refraction and thought it was likely that the near rings were refracting. He chalked it up to ocular surface disease and when he examined the patient again at postoperative week 4, UCVA was 20/60 and J2 at near, “ Presbyopia-correcting IOLs raise the bar for delivering a full range of vision. They add complexity to patient selection and expectations, and require a higher level of surgical precision to achieve exceptional outcomes. ” - Sumit “Sam” Garg, MD EWAP CATARACT/IOL December 2017 63 continued on page 64