Eyeworld

Supported by an unrestricted educational grant from Abbott Medical Optics For every patient who will receive a toric or pres- byopia-correcting IOL, it is important to have accurate biometry, with measurements from an immersion A-scan and an optical biometer device. Also, as stated before, corneal topography is import- ant to validate K readings. It is important when implanting toric IOLs to consider the effect of posterior corneal astigmatism and per- haps utilize the Barrett Toric Calculator (ascrs.org). To determine each pa- tient's needs and expectations from surgery, we also perform a mini personality survey. Managing postop error I usually wait at least 6 to 8 weeks before defining post- operative error because the IOL may shift or tilt and the cornea may be healing. Post- operative dry eye can change the refraction by 0.75 D, so it must be treated. In research by Donnenfeld et al., cyclo- sporine 0.05% treatment in eyes receiving multifocal IOLs increased visual quality and decreased signs of dry eye. 4 I tolerate 0.5 D of myo- pia, hyperopia, or astigmatism with a presbyopia-correcting IOL. Errors exceeding 0.5 D must be treated because they increase dysphotopsia, halo, and glare. There are a number of ways to correct postoperative errors. 5 For large IOL-based er- rors, a lens exchange may be necessary. If small astigmatic errors occur, surgeons can per- form limbal relaxing incisions or astigmatic keratotomy at the slit lamp or with a fem- tosecond laser. Surgeons also can perform LASIK or PRK. I usually avoid piggyback IOLs because of risks of glaucoma or bleeding, although these risks are small. 6 Surgeons also should consider that some patients may prefer to wear a slight corrective lens for driving rather than having a second procedure. It is important to discuss all these options and their associated risks with your patients facing a postoperative surprise and together make an informed decision. Conclusion Chair time before surgery will decrease a surgeon's chair time after surgery. Surgeons need to take adequate time for preop assessments, closely examining the cornea, identi- fying other ocular disease, and setting patients' expectations to a reasonable level. If surgeons take this time, fewer postoperative surprises will develop and more patients will be happy with their procedures because their expectations are set and surgeons are more likely to meet them. References 1. Braga-Mele R, et al. Multifocal intraocular lenses: relative indi- cations and contraindications for implantation. J Cataract Refract Surg. 2014;40:313–322. 2. Visser N, et al. Toric intraocular lenses: historical overview, patient selection, IOL calculation, surgical techniques, clinical outcomes, and complications. J Cataract Refract Surg. 2013;39:624–637. 3. Epitropoulos AT, et al. Effect of tear osmolarity on repeatability of keratometry for cataract surgery planning. J Cataract Refract Surg. 2015;41:1672–1677. 4. Donnenfeld ED, et al. Cyclosporine 0.05% to improve visual outcomes after multifocal intraocular lens implantation. J Cataract Refract Surg. 2010;36:1095–1100. 5. Alio JL, et al. Enhancements after cataract surgery. Curr Opin Ophthal- mol. 2015;26:50–55. 6. Iwase T, et al. Elevated intraocular pressure in secondary piggyback in- traocular lens implantation. J Cataract Refract Surg. 2005;31:1821–1823. Dr. Braga-Mele is professor of ophthalmology, University of Toronto, and director of cataract surgery, Kensington Eye Institute, Toronto. She can be contacted at rbragamele@ rogers.com. " Chair time before surgery will decrease a surgeon's chair time after surgery. " –Rosa Braga-Mele, MD, MEd, FRCSC 7

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