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EW San Diego 2015 3 by Brad Black, MD Correcting astigmatism with the AcrySof IQ Toric IOL W hile discussing current "state of the art" cataract surgery with patients, one is constantly reminded of how highly sophisticated and advanced the procedure has become. The evolution of cataract surgery over the last 2 decades has been quite dramatic, and nowhere is it more evident than with the develop- ment and use of the toric intraocular lens to correct astigmatism at the time of cataract surgery. It is up to us as surgeons to ex- plain all that is available to patients, educate them as to their "opportuni- ties," and allow them to make an in- formed decision as to what direction they would like to take. The technol- ogy explosion that has occurred has allowed us to greatly improve our outcomes and offer so much more to our patients. There is no question that we have truly raised the bar with our ability to offer femtosecond laser-assisted cataract surgery, new measuring instrumentation and technology, more sophisticated IOL calculation formulas, recently de- veloped surgical planning software, improved intraoperative aberrome- try, etc. As an original investigator of the AcrySof IQ Toric IOL (Alcon, Fort Worth, Texas), I became particularly enamored with the technology very early on. I was very familiar with acrylic material, and the AcrySof platform was the perfect starting point for a toric intraocular lens. As all surgeons know, the material is particularly bioinert and very "friendly" to the capsule. There is a tackiness that stabilizes the implant within the bag, minimizing any ro- tation postoperatively. There is very little fibrosis and contraction of the capsule and nearly perfect centra- tion. As compared to the previous toric IOL, the AcrySof IQ Toric is a quantum leap improvement. In a landmark study of 6,000 patients, 1 Warren Hill, MD, evaluat- ed preoperative keratometry read- ings and demonstrated that nearly one third to one half of all cataract patients would benefit from a toric lens. Initially, we were limited to fully correcting astigmatism of up to 2 diopters only while utilizing 3 different powers of toricity. Recent- ly, however, an expanded range of toric powers has enabled us to treat virtually 99% of all patients with astigmatism, based on Dr. Hill's study. We can now correct up to 4 D of cylinder in half diopter incre- ments, making this an extremely valuable resource for surgeons and their patients. Surgically, implantation of the AcrySof IQ Toric lens requires very little modification to one's tech- nique. Traditionally, the limbus is marked preoperatively at the 3, 6, and 9 o'clock positions with the patient sitting upright using var- ious instruments that have been designed specifically for this. This can be done either by the surgeon or a nurse in the preoperative area. These marks are then used intraop- eratively to orient the toric IOL onto the intended axis when the patient is in the supine position accounting for any cyclorotation that may have occurred. The recently developed Verion System (Alcon) has helped improve this entire process and made it much more accurate, in my opinion. By utilizing an overlay visible in the mi- croscope ocular that highlights the intended axis, the surgeon simply rotates the toric IOL, removes any remaining viscoelastic material, and makes any final adjustments for an extremely accurate alignment. The system does not require any preop- erative marking because it utilizes a high definition image taken preoper- atively that identifies limbal vessels and iris structures that are then used intraoperatively to identify the exact orientation for the toric implant. Axis power and orientation can be confirmed with intraoperative aber- rometry as well, further refining our outcomes. This system has been ex- tremely useful and beneficial in our surgical facility. The Verion System has helped improve our efficiency in the OR while offering a very high degree of accuracy and eliminating the need to mark the limbus both pre- and intraoperatively. I feel it is very important when discussing surgery with patients to explain that the toric IOL of- fers much more than just "going without glasses." I feel it is opti- cally superior and makes so much more sense to correct astigmatism internally rather than at the spec- tacle plane. For those who "want to wear glasses" postoperatively, their spectacles are clear except for the bifocal, less expensive, thinner, and lighter weight. Further, there certainly is less dependency on the spectacles and the capability of wearing non-prescription sunglasses. We often use a modified or partial monovision to minimize the need for readers in these patients as well. Toric IOLs are quite useful in patients who have known ocular pathology. The goal with cataract surgery is to maximize the image at the fovea so that even patients with some ocular pathologies can benefit from this lens. Importantly, the surgeon must manage expectations in these situations preoperatively as well as postoperatively. We have found the AcrySof IQ Toric to be extremely beneficial for our patients. Some of our happiest patients are those who come in for their day 1 postoperative visit and realize that in a matter of 15 min- utes we have corrected a problem that they have had since they were born. This can be very dramatic for patients as well as their family and is often a "life changing" experience. Reference 1. Provided courtesy of Warren Hill, MD. www.doctor-hill.com/iol-main/astigmatism_ chart.htm. Accessed March 18, 2015. Dr. Black is in private practice in Jeffersonville, Ind. He can be contacted at drbradblack@aol. com. " The evolution of cataract surgery over the last 2 decades has been quite dramatic, and nowhere is it more evident than with the development and use of the toric intraocular lens to correct astigmatism at the time of cataract surgery " Brad Black, MD Prevalence of corneal astigmatism in patients undergoing cataract surgery

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