Eyeworld

by Kendall E. Donaldson, MD, MS Succeeding with accommodating IOLs Accommodative IOLs extend presbyopia correction options to a broader range of patients O phthalmologists can turn to an increasingly broad array of intraocular lenses (IOLs) to correct presby- opia, and accommodative IOLs offer opportunities for patients who may not be suitable candidates for multifocal IOLs. Case report A 66-year-old attorney complained of blurred vision and was highly motivated to have presbyopia correc- tion. A very athletic, active person, he had worn monovision contact lenses previously. His best corrected visual acuity was 20/40 (dominant) and 20/30, and his intraocular pres- sures were normal. Counseling presbyopia-correcting IOL patients To set reasonable expectations, take care to advise patients about the potential for: • Glare/halos (multifocals) • Light dependency at near (some multifocals) • Limitations in intermediate vision (some multifocals) or near vision (accommodating) • One eye will be stronger for distance and one stronger for near, if monovision or mini-monovision is planned; emphasize using both eyes together He played golf and tennis, enjoyed going out at night, and was not willing to tolerate glare or halo. We wanted to ensure the technology we chose fit his lifestyle long term. We implanted the Crystalens in his non-dominant eye, selecting a slightly myopic target, and he is very pleased. He wears reading glasses at his desk at work but is completely spectacle independent on weekends. Accommodative technology Accommodating technology is par- ticularly useful for several groups of patients who might not be appro- priate candidates for other presby- opia-correcting IOLs. For example, guttata can affect vision in patients with mild Fuchs' dystrophy even if they do not have corneal edema. It can also be useful in patients with anterior basement membrane disease if irregular astigmatism is not severe or in those with mild macular pathology where the potential acui- ty meter or potential acuity pinhole shows good visual potential. Some questions remain with accommodative IOLs. For example, OCT has shown that the optic of ac- commodative IOLs most likely shifts forward approximately 1 D, and we do not achieve full accommodation. We also need to consider where the lens will sit and how predictable it is. We began using the Trulign toric IOL approximately one year ago, combining accommodation with astigmatism correction, which has continued from page 132 Correcting the problem To correct postoperative residual astigmatism, I measure the manifest refraction. Next, I measure the IOL axis and know its toricity. We plug this information into astigmatism- fix.com. I rotate the IOL if astigmatism can be neutralized and the spherical equivalent is near target. I mark the current and ideal axis, loosen the IOL with viscoelastic, rotate the IOL, and remove the viscoelastic. Laser vision correction is recom- mended when the spherical equiv- alent is not at target, astigmatism is not neutralizable, or the IOL cannot be rotated easily. Significant residual astigmatism is uncommon, but we need to know how to prevent it and establish a plan to correct it if necessary. This will become increasingly important when we use toric multifocal IOLs, which are very sensitive to residual astigmatism. Dr. Berdahl is assistant professor of ophthalmology, University of South Dakota, and in practice at Vance Thompson Vision in Sioux Falls, S.D. He can be contacted at 605-361-3937 or john.berdahl@vancethompsonvision. com. 134 Crossing the finish line: Launching your premium technology practice Misalignment % loss Abolute loss T3 (1.03 D) T9 (4.11 D) 0 degrees 0% 0 D 0 D 5 degrees 17.5% 0.18 D 0.71 D 10 degrees 35% 0.36 D 1.43 D 15 degrees 50% 0.51 D 2.05 D 30 degrees 100% 1.03 D 4.11 D Figure 2. Vision loss as a result of IOL misalignment Kendall E. Donaldson, MD, MS

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