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Visual Performance of Center-Distance Multifocal Contact Lenses Fit Using a Myopia Control Paradigm

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Visual Performance of Center-Distance Multifocal Contact Lenses Fit Using a Myopia Control Paradigm VISUAL PERFORMANCE OF CENTER-DISTANCE MULTIFOCAL CONTACT LENSES FIT USING A MYOPIA CONTROL PARADIGM By Hannah R. Gregory, BS A thesis submitted to the Graduate Program, University of Houston College of Optometry In partial fulfillment of the requirements for the degree of MASTER OF SCIENCES In PHYSIOLOGICAL OPTICS & VISION SCIENCE Chair of Committee: Eric R. Ritchey, OD, PhD Co-chair of Committee: David A. Berntsen, OD, PhD Committee Member: Han Cheng, PhD, OD University of Houston May 2021 Acknowledgments I would like to thank my advisor, Dr. Eric Ritchey, for his many hours of teaching and directing me throughout this entire process. His passion for teaching and research is evident in all that he does. He welcomed me into his new lab when it first began and made sure I understood what it really meant to be a researcher, explaining how it is relevant to the optometric world, especially in the field of myopia progression. My research project would not be where it is without all of his help. He always made himself available when I needed help, especially when aiming for deadlines throughout this process. His guidance truly pushed me to become the professional I am today. I am also so thankful for the support of his wife, Dr. Moriah Chandler, and his children. I would also like to thank my co-advisor, Dr. David Berntsen, for his support and help throughout my schooling. He also spent countless hours, aiding in analyzing data and explaining it in a way that I could understand to utilize in my project. His dedication to the field of myopia management is inspiring and has made me want to pursue this throughout my career. Even with him being so busy, Dr. Berntsen always made time to help when I needed it. I would also like to thank his wife, Monique, and his children for being present throughout the process. I would like to extend my gratitude to Dr. Cheng for being part of my thesis committee. She has been a constant light and encouragement through the process of me writing my thesis. I appreciate her assisting in reviewing my thesis and helping to make me the best clinician that I can be. Her dedication to the students she works with is comforting, especially in a difficult program. I would like to also thank Dr. Frishman for her assistance in the graduate program. She always made sure that I was confident in the program and ensured that we had the funding necessary to continue in the dual program. She is a constant source of motivation with her ii dedication to research. Furthermore, I would like to thank the NIH/NEI for providing grant support (T35-EY007088 and P30-EY07551). Finally, I would like to thank my parents and siblings for their support throughout my academic career. My parents have always been a source of motivation and confidence, even in the most trying times. Both my brother and sister have been a source of comfort and challenge, especially with all of us being in the medical field. My family has been my stability throughout my entire schooling, and I could not imagine being here without them. iii Abstract Purpose: Multifocal contact lenses (MFCLs) are increasingly being prescribed for non- presbyopic patients (e.g., myopia control, digital eye strain, etc.). It is important to understand how these contact lenses affect visual performance. MFCLs and single vision contact lenses (SVCLs) were evaluated under several illuminations and contrast levels. Methods: Twenty-five non-presbyopic adults with -1.00 D astigmatism or less and spherical equivalent refraction (SER) between -0.75 DS and -6.00 DS at the corneal plane were enrolled and fitted binocularly in three contact lens designs using a myopia control paradigm. Two lenses were center-distance MFCLs (Biofinity “D” +2.50 add, NaturalVue Multifocal) and one was a spherical SVCL (Biofinity). Subjects were masked to the lens type. High-(HC) and low-contrast (LC) logMAR visual acuity (VA) was measured at distance in photopic, mesopic, and mesopic with glare lighting. Photopic high-contrast acuity and reading speed were measured at near. Data were analyzed using repeated-measures analyses of variance (RM-ANOVA) with adjusted post- hoc t-tests, when appropriate. Results: The mean (± SD) age and SER were 24.1 ± 1.5 years and OD: –3.38 ± 1.53 DS (range – 1.00 to –5.00 DS), OS –3.29 ± 1.66 DS (range –0.75 to –5.75 DS), respectively. HC and LCVA depended on lighting and lens type (lens x contrast x lighting interaction; P = .015). HC was always better than low (all P < .05). The acuity loss in photopic HCVA between SVCLs and MFCLs was statistically significant, approximately 1.5 to 2 letters (P = .017). Mesopic, HCVA with MFCLs was 4 to 5 letters worse than SVCLs (P < .001). All lenses performed better in photopic lighting (all P < .001). Photopic, LCVA with both MFCLs was 5-6 letters worse than iv SVCLs. For mesopic LCVA without glare, loss was just over 2 lines for MFCLs compared to SVCLs. Reductions in LCVA between photopic and mesopic lighting differed by lens types (SVCL versus MFCLs; P < .0001). In mesopic lighting, the addition of glare reduced VA by about 3 letters (0.065 logMAR; P < .00001); VA reduction did not depend on lens design (SVCL vs MFCLs; P = .17). Reading performance in words per minute (WPM) was worse with MFCLs (Biofinity MFCL 144 ± 22 WPM, NaturalVue multifocal 144 ± 28 WPM) than with SVCLs (156 ±23 WPM; P = .019) regardless of letter size (P = .13). No difference in visual acuity between the MFCLs was detected (all P > 0.05). Conclusion: Compared to the SVCL, both MFCL designs resulted in reductions in distance VA under photopic low-contrast and mesopic, high- and low-contrast conditions. Additional reductions in VA were observed with glare, but these reductions did not differ between lens designs. High-contrast VA does not fully describe the effect of MFCL optics on visual acuity. Additional work is needed to better ascertain visual performance with multifocal lens designs. v Table of Contents Page Acknowledgments ..................................................................................................................................... ii Abstract ........................................................................................................................................................ iv Table of Contents ...................................................................................................................................... vi List of Figures ........................................................................................................................................... vii List of Tables ........................................................................................................................................... viii Chapter 1: Introduction ........................................................................................................................... 1 1.1 Digital Eye Strain .................................................................................................................................................... 2 1.2 Significance of Myopia ......................................................................................................................................... 3 1.3 Visually-Guided Ocular Growth and Myopia .............................................................................................. 5 1.4 Multifocal Contact Lenses and Myopia Control ......................................................................................... 6 1.5 Visual Performance of Multifocal Contact Lenses .................................................................................... 8 1.6 Reading Performance ......................................................................................................................................... 11 1.7 Glare Affecting Visual Performance ............................................................................................................. 13 1.8 Pupil Size .................................................................................................................................................................. 14 1.9 Specific Aims ........................................................................................................................................................... 16 Chapter 2: Visual Performance of Center-Distance Multifocal Contact Lenses Fit Using a Myopia Control Paradigm .................................................................................................................... 17 2.1 Introduction ............................................................................................................................................................ 17 2.2 Methods ..................................................................................................................................................................... 19 2.3 Results ........................................................................................................................................................................ 25 2.4 Discussion ................................................................................................................................................................. 31 Chapter 3: Conclusions ......................................................................................................................... 37 References ...............................................................................................................................................
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