Eyeworld

63 EW RESIDENTS January 2015 in this study due to dissatisfaction with IOL implantation, compared to none in the Zhang study. 3,5 This suggests that surgeons should pro- ceed with caution when considering surgical presbyopic treatments and consider preoperative heterophoria testing. Mini-monovision was compared with MFIOL implantation rather than true monovision. The authors suggest that the myopic defocus of –0.50 in the dominant eye and mini-monovision may contribute to the better outcomes in their study when compared to previous reports. A comparison or discussion of mini-monovision versus true monovision is warranted as most other studies of monovision versus multifocal IOL aim for true monovi- sion anisometropia of around 1.5 to 2.00 diopters. 3,5,8,9 Studies of mini-monovision versus oth- er surgical presbyopic treatments are limited. To our knowledge, this study is unique in compar- ing mini-monovision (0.75 D of anisometropia) to a multifocal IOL. Lastly, as we are located in the United States we must comment on the generalizability of this study to the United States market. The current market forces are such that the most utilized multifocal IOL is diffractive rather than the refractive IOL that was evaluated in this study. Thus, comparing pseudophakic monovision to a diffractive MFIOL may be a more generalizable study to patients in the United States. In the January issue of JCRS, Labiris et al demonstrate the out- come differences in patient satis- faction, spectacle dependence, and dysphotopsias when using pseu- dophakic mini-monovision versus MFIOLs. There was previously little in the literature regarding patient satisfaction outcomes when com- paring these two modalities. There is also little in the international literature regarding success with pseudophakic monovision. The authors provide a good therapeutic algorithm for mini-monovision correction in this paper. This study illustrates that both mini-monovision and MFIOLs are acceptable when aiming to address pseudophakic presbyopia; patients in both groups experienced good outcomes for distance vision and visual function. However, the total spectacle independence, compared to 31.4% from the mini-monovision group. Discussion This study presents new and interesting information in the arena of pseudophakic presbyopia correction—more specifically, monovision versus multifocal intraocular lens implantation. There were several limitations in the reviewed paper. The first is regarding the study design and ran- domization process. The randomiza- tion process for this study is interest- ing and may not be feasible in the United States given the additional cost of the advanced technology IOL and the potential for adding bias to the results. A study authored from the U.S. utilized a prospective conve- nience sample given the difference in out-of-pocket costs for a multi- focal IOL. 3,4 There are other similar studies comparing monovision ver- sus multifocal IOL where the patient is randomized and blinded to the type of intraocular lens implanted. 5,6 It is not clear the extent of the in- formed consent process for multifo- cal IOL versus mini-monovision for this study nor is it explicitly stated that the patients were blinded to the type of lens they were receiving. A variety of preoperative testing is currently performed for patients considering pseudophakic monovi- sion and, in addition to routine clinical examination, can include any or all of the following tests: ocular dominance, contact lens trial, traditional cover testing, monovi- sion threshold testing, Mallett dis- parity test, and double Maddox rod testing. The reviewed study utilized all of the aforementioned tests with the exception of the contact lens tri- al. Other studies employ a variety of preoperative assessments, thus small variations in outcomes including patient satisfaction and spectacle independence may be due to slightly dissimilar patient populations. Heterophoria, which could result in less than optimal visual outcomes, was given significant emphasis during the preoperative assessment in the reviewed study when compared to similar stud- ies. As there was no contact lens trial prior to randomization and surgical intervention, perhaps this heterophoria screening was nec- essary to decrease the chances of encountering patients unable to tolerate monovision. Many surgeons routinely initiate a contact lens trial, especially in patients being evalu- ated for monovision laser refractive surgery, 7 or phakic/pseudophakic trial prior to surgical monovision. 8 One prior study utilizes a monovi- sion threshold test to determine the amount of tolerated anisometropia before monofocal IOL implan- tation. 3 Another study excludes patients with exophoria greater than 10 D and strong ocular dominance. 9 In the study by Wilkins et al neither heterophoria testing nor contact lens trial was done. 5 Interestingly, there were several IOL exchanges patients with multifocal lenses experienced better binocular UNVA and higher rates of spectacle inde- pendence while the mini-monovi- sion group had fewer dysphotopsias postoperatively. These conclusions emphasize the importance of the preoperative visit and screening. It is paramount that clinicians thoroughly evaluate each patient's refractive goals and discuss post- operative expectations of spectacle dependence and visual disturbances to ensure successful subjective and objective outcomes. EW References 1. Papadopoulos PA, Papadopoulos AP. Current management of presbyopia. Middle East Afr J Ophthalmol. 2014;21(1):10–17. 2. Bellucci R. Multifocal intraocular lenses. Curr Opin Ophthalmol. 2005;16(1):33–37. 3. Zhang F, Sugar A, Jacobsen G, Collins M. Visual function and patient satisfaction: Comparison between bilateral diffractive multifocal intraocular lenses and monovi- sion pseudophakia. J Cataract Refract Surg. 2011;37(3):446–453. 4. Zhang F, Sugar A, Jacobsen G, Collins M. Visual function and spectacle independence after cataract surgery: Bilateral diffractive multifocal intraocular lenses versus monovi- sion pseudophakia. J Cataract Refract Surg. 2011;37(5):853–858. 5. Wilkins MR, Allan BD, Rubin GS, et al. Ran- domized trial of multifocal intraocular lenses versus monovision after bilateral cataract surgery. Ophthalmology. 2013;120(12): 2449–2455.e1. 6. Ito M, Shimizu K, Niida T, Amano R, Ishikawa H. Binocular function in patients with pseu- dophakic monovision. J Cataract Refract Surg. 2014;40(8):1349–1354. 7. Farid M, Steinert RF. Patient selection for monovision laser refractive surgery. Curr Opin Ophthalmol. 2009;20(4):251–254. 8. Greenbaum S. Monovision pseudophakia. J Cataract Refract Surg. 2002;28(8): 1439–1443. 9.Ito M, Shimizu K. Reading ability with pseudophakic monovision and with refractive multifocal intraocular lenses: comparative study. J Cataract Refract Surg. 2009;35(9):1501–1504. Contact information Aaron: mmendic@emory.edu Jones: jjones2@emory.edu From left to right: Jennifer Kim, MD, Michael Shumski, MD, Maria Aaron, MD, Jeremy Jones, MD, Heather Weissman, MD, Jessica Shantha, MD, and Abdallah Jeroudi, MD. Not pictured: Monica Zhang, MD Source: Emory Eye Center

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