Task-orientated visual satisfaction evaluation could help lens design selection

Using a task-orientated visual satisfaction evaluation has potential to help in lens design selection and predicting wearing success, according to a paper in Journal of Optometry.

Dr Joan Gispets et al., University Vision Centre, Universitat Politècnica de Catalunya, Terrassa, Barcelona, Spain, completed a longitudinal prospective, cross-over, double-masked study on 22 presbyopic patients were randomly and alternatively fitted with two types of multifocal lenses.

The patients followed two 14-day trial periods, after which overall satisfaction was evaluated. The wearing success of the lens was assessed via the percentage of subjects choosing to continue wearing a multifocal lens and by the total number of subjects continuing to wear the lenses six months later. Habitual tasks were identified by observation distance, visual demand level and time allocation.

Visual satisfaction was affected by viewing distance and visual demand level. It decreased when tasks required higher visual demands involving near and far distance vision, compared to intermediate vision or a combination of near and far vision. It was found that the main reason for patient discontinuation of multifocal lenses was due to insufficient quality of vision.

Finally, 78% of the patients included in the study chose to continue wearing the lenses, with 1 patient deciding to wear them daily 6 months after study completion. The investigation suggests that a task-orientated visual satisfaction evaluation could be beneficial towards the design selection of a patient's lens and the determination of wearing success.