Eyeworld

Figure 2. Rotational stability according to Tecnis Toric studies Source: Daniel Black, MBBS, FRANZCO and against-the-rule (0.19 D, SD 0.30, 97.5% with 0.5 D or less of residual postop), proba- bly due to the nomogram. The use of digital marking resulted in significantly less postop astigmatism than ink marking (p=0.02, Figure 1) and ensured that none of the patients had more than 1.0 D of residual astigmatism. The dig- ital marking system effectively reduces the outliers, improving results. Rotational stability Alignment is notoriously import- ant for toric correction, with ev- ery 10 degrees of misalignment equating to a 6% loss of toric correction. Rotational stability is thus a particularly important factor in IOL selection. In terms of rotational sta- bility, these study results with the Tecnis Toric match those of other published Tecnis Toric studies, which show a mean ro- tation ranging from 2.1 degrees after 2 weeks of follow-up to 3.4 degrees after 2 months of follow-up; meanwhile, a mean rotation of less than 3 degrees was reported by the study with the longest follow-up of 2 years (Figure 2). It is possible for each and every surgeon to achieve the same results, but you have to pay attention to detail. Biometry on virgin tear film is the single most important factor, and you have to be consistent and ac- curate with your capsulorhexis, be careful with the alignment of the IOL, and ensure thorough OVD removal. The success of the Tecnis Toric is the result of its opti- cal synergy: Tecnis has been proven to provide long-term correction of both lower order aberrations of sphere and cylin- der; we know that for patient satisfaction we have to correct more higher order aberrations, and Tecnis is the only lens that corrects both chromatic and spherical aberration; and the lens maximizes visual quality through an acrylic material with a low refractive index to minimize dysphotopsias that is glistening-free and allows full light transmission. References 1. Mingo-Botin D, et al. Compari- son of toric intraocular lenses and peripheral corneal relaxing incisions to treat astigmatism during cataract surgery. J Cataract Refract Surg. 2010;36:1700–8. 2. Hirnschall N, et al. Correction of moderate corneal astigmatism during cataract surgery: Toric intraocular lens versus peripheral corneal relax- ing incisions. J Cataract Refract Surg. 2014;40:354–61. continued from page 1 though programming the aspirations of the patient are at least as important. Detailed ocular surface ex- amination pre- and postop are a must, and managing residual refractive error is of paramount importance. Nevertheless, unlike multifocal IOLs, the extended range of vision IOL is more forgiving in terms of residual error. Should postoperative re- fractive surprises occur, the flat defocus curve leaves a margin for some error, and surface ablation to treat residual error is more possible with the ex- tended range of vision IOL than with multifocal IOLs. Moreover, neural adaptation is less of an issue. Personal experience with extended range of vision lenses At Laxmi Eye Institute, sur- geons implanted the Symfony extended range of vision IOL bilaterally in 24 patients, aiming for micro-monovision. Patients' best corrected visual acuity (BCVA) for distance was 20/20 with spherical equivalents between –0.25 and –0.50 D. Uncorrected near visual acuity was N6 and uncorrected inter- mediate visual acuity N8. Compared to a Tecnis monofocal, Symfony provided a mean visual acuity of 20/25 or better through 0.75 D of defo- cus and 20/40 or better through 1.5 D of defocus (Figure 1). The surgeons concluded that Symfony is an excellent alternative for a larger section of the cataract population who have no issues wearing read- ing glasses for small print. 3 Sponsored by Abbott Medical Optics

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