Presbyopia correction with multifocal contact lenses: Evaluation of silent reading performance using eye movements analysis

Visual performance and quality of life in myopic adolescents with pupil-optimised multifocal versus single-vision contact lenses

CLINICAL RELEVANCE

Myopia control is a prominent area of global research, with multifocal contact lenses identified as an effective intervention for adolescents.

BACKGROUND

This study aims to evaluate the visual performance and vision-related quality of life (QoL) of myopic adolescents when corrected with pupil-optimised multifocal soft contact lenses (MFSCLs) versus single-vision contact lenses (SVCLs), with each participant serving as their own control.

METHODS

Thirty-five myopic adolescents, habitually wearing SVCLs and fitted with pupil-optimised MFSCL with mid-addition power, were recruited. The assessment included distance visual acuity (DVA), near visual acuity (NVA), maximum reading speed (MRS), reading acuity (RA), contrast sensitivity (CS), and stereoacuity (SA) in photopic conditions for both types of lenses. Vision-related QoL was quantified twice for both lens types using the National Eye Institute Visual Function Questionnaire (NEI VFQ-42), covering 13 vision-specific domains.

RESULTS

Comparisons of visual outcomes between MFSCLs and SVCLs for the same subjects revealed statistically significant differences in DVA (p = 0.010), NVA (p = 0.014), MRS (p = 0.044), and RA (p < 0.001), with SVCLs outperforming in DVA only. No significant difference in CS and SA was observed between the two lens types. According to the NEI VFQ-42, scores for clarity of vision, far vision, glare, and satisfaction with correction were higher with SVCLs, while the score for near vision was higher with MFSCLs. When fitted with MFSCLs, no significant correlations were found between pupil size and age of the patient with any visual examination parameters. However, there was a significant negative correlation between the DVA, NVA and the spherical equivalent of the lens.

CONCLUSION

MFSCLs with mid-add power significantly improve NVA, MRS, and RA, albeit with a reduction in DVA compared to SVCLs. While SVCLs were associated with better clarity of vision, far vision, and satisfaction with correction, MFSCLs offered superior performance in near vision tasks, according to the NEI VFQ-42 scores.

BCLA CLEAR Presbyopia: Management with contact lenses and spectacles

This paper seeks to outline the history, market situation, clinical management and product performance related to the correction of presbyopia with both contact lenses and spectacles. The history of the development of various optical forms of presbyopic correction are reviewed, and an overview is presented of the current market status of contact lenses and spectacles. Clinical considerations in the fitting and aftercare of presbyopic contact lens and spectacle lens wearers are presented, with general recommendations for best practice. Current options for contact lens correction of presbyopia include soft simultaneous, rigid translating and rigid simultaneous designs, in addition to monovision. Spectacle options include single vision lenses, bifocal lenses and a range of progressive addition lenses. The comparative performance of both contact lens and spectacle lens options is presented. With a significant proportion of the global population now being presbyopic, this overview is particularly timely and is designed to act as a guide for researchers, industry and eyecare practitioners alike.

Gaze and behavioural metrics in the refractive correction of presbyopia

PURPOSE

To investigate gaze and behavioural metrics at different viewing distances with multifocal contact lenses (MFCLs), single vision contact lenses (SVCLs) and progressive addition lenses (PALs).

METHODS

Fifteen presbyopic contact lens wearers participated over five separate study visits. At each visit, participants were randomly assigned to wear one of five refractive corrections: habitual PAL spectacles, delefilcon A (Alcon Inc.) MFCLs and three separate pairs of delefilcon A single vision lenses worn as distance, intermediate and near corrections. Participants wore a Pupil Core headset to record eye and head movements while performing three visual tasks: reading, visual search and scene observation. Data were investigated using linear regression and post-hoc testing. Parameters of interest included gaze (fixation duration, head movement) and behavioural (reading speed, reading accuracy, visual search time) metrics.

RESULTS

Reading speed in SVCLs was significantly faster than in MFCLs and PAL spectacles (F = 16.3, p < 0.0001). Refractive correction worn did not influence visual search times (F = 0.16, p = 0.85). Fixation duration was significantly affected by the type of visual task (F = 60.2, p < 0.001), and an interaction effect was observed between viewing distance and refractive correction (F = 4.3, p = 0.002). There was significantly more horizontal and vertical head movement (F = 3.2, p = 0.01 and F = 3.3, p = 0.01, respectively) during visual search tasks when wearing PAL spectacles compared to SVCLs or MFCLs.

CONCLUSION

This work showed that the type of refractive correction affects behavioural metrics such as reading speed and gaze behaviour by affecting horizontal and vertical head movements. The findings of this study suggest that under certain conditions, wearers of MFCLs make fewer head movements compared to PAL spectacles. Gaze behaviour metrics offer a new approach to compare and understand contact lens and spectacle performance, with potential applications including peripheral optical designs for myopia management.