Abstract
Purpose :
One issue in the myopic population is aesthetic management of ophthalmic lenses such as thick edges and unsightly rings on the lens periphery. For improving aesthetic, a novel design proposes to thin the lens by steadily decreasing its back surface curvature in the temporal sides. To evaluate its impact, we designed an study where participants had to drive and perform a secondary task.
Methods :
5 women and 4 males ([21-36yo]) with a myopia ranging from -3 to -8.25dp were seated in car simulator. They had to drive along a highway road at a constant speed of 100 km/h to maintain a high level of workload and visual solicitation, and to detect numbers associated with ‘Montréal’ on different road signs displayed on a navigation device 8 times per trial. Driving performance was evaluated by standard deviation of lane position (SDLP), speed variability (SV), success rate in the secondary task, and comfort as evaluated by a simulator sickness questionnaire (SSQ). These were measured and compared between three lens solutions: the driver’s habitual single vision lenses (LH) and non-habitual single vision lenses: a reference lens (LA) and the new lens design (LB).
Results :
SSQ scores were significantly different between the non-habitual lenses (Z(1,8) = -2.082, p < 0.05). Reported symptoms were driven by greater oculomotor symptoms (Z(1,8) = -2.384, p < 0.05) while wearing LB. Drivers also self-reported that they were less willing to wear this lens for driving. SDLP (t(1,8) = -5.894; t(1,8) = -3.921; p < 0.05) and SV (t(1,8) = -3.617; t(1,8) = -2.691; p < 0.05) were both impacted by the GPS tasks. With LB, the driving speed was significantly decreased (t= -5.894; p < 0.05).
Conclusions :
LB new lens design with a thinning in the temporal side gave rise to strong visually induced discomfort. Driving measures revealed also that drivers adopt a more cautious strategy by reducing their speed while performing the secondary task. This is in addition to a significant impact of both non-habitual lenses on driving performance which may be due to the absence of a time adaptation or to the temporal lens design effect. Participants verbally reported difficulties with peripheral vision and specifically in detecting the number displayed on the GPS with LB despite no success rate difference. Our study reveals that the management of lens aesthetic may impair the daily behavior of myopic wearers such as driving behavior and comfort.
This abstract was presented at the 2019 ARVO Annual Meeting, held in Vancouver, Canada, April 28 - May 2, 2019.