We thank Dr Ho for his commentary on our manuscript.
It is correct that both yellow (blue-blocking) and clear intraocular lenses (IOLs) were included in our comparison study, with the majority being the clear type. Because of the general controversy of contrast sensitivity being affected by the yellow-colored blue-blocking IOLs, we performed a sub-analysis to assess if there was a difference between these lens types in our study. Interestingly, the sub-analysis between the clear and yellow IOLs showed a trend that the clear multifocal IOLs had a slightly lower mean deviation (MD) score than the yellow IOLs. This was not reported owing to low power and lack of statistical difference. Extension of this study with larger numbers in both groups of IOLs would be required to draw out this conclusion. We concluded that the multifocality of the IOLs is likely playing a greater role in the contrast sensitivity issue, as supported by previous studies.
- 1. Montes-Mico R., and Alio J.L.: Distance and near contrast sensitivity function after multifocal intraocular lens implantation. J Cataract Refract Surg 2003; 29: pp. 703-711
- 2. Calladine D., Evans J.R., Shah S., and Leyland M.: Multifocal versus monofocal intraocular lenses after cataract extraction. Cochrane Database Syst Rev 2012; 9: pp. CD003169
- 3. Mesci C., Erbil H.H., Olgun A., et al: Differences in contrast sensitivity between monofocal, multifocal and accommodating intraocular lenses: long-term results. Clin Experiment Ophthalmol 2010; 38: pp. 768-777
- 4. Kamlesh , Dadeya S., and Kaushik S.: Contrast sensitivity and depth of focus with aspheric multifocal versus conventional monofocal intraocular lens. Can J Ophthalmol 2001; 36: pp. 197-201
- 5. Montes-Mico R., Espana E., Bueno I., et al: Visual performance with multifocal intraocular lenses: mesopic contrast sensitivity under distance and near conditions. Ophthalmology 2004; 111: pp. 85-96