The effect of multifocal contact lens (MFCL) and combined therapy of MFCL and atropine on the eye-related functions among adult myopes.

Multifocal contact lenses (MFCLs) have shown promising results in slowing myopia progression in children. However, the underlying mechanism for treating myopia with MFCLs is still uncertain; it is assumed that MFCLs reduce hyperopic defocus in the periphery, inhibit accommodation lag, and improve the amplitude of accommodation in myopes. It has been demonstrated that myopic blur induced by the peripheral portions of these lenses can reduce myopia progression in children by 36.4% and axial elongation by 37.9%. However, the effect of MFCL on the ability of the eye to detect the stimulus properties such as contrast, colour, and motion remains unknown, and it is possible that MFCL impact these functions, which may contribute to its effect in slowing myopia progression. It is assumed that both optical and pharmaceutical treatments use two different mechanisms to reduce myopia progression and combining both interventions (known as combined therapy) may provide better myopia control than one treatment alone (monotherapy). The primary objective of this study is to examine the effects of MFCL alone (monotherapy) and its combination with 0.05 % atropine sulfate eye drops (combined therapy) on a range of basic visual functions (contrast sensitivity, colour, and motion detection), pupil size, and image quality. This research is expected to provide a greater understanding of the effect of MFCL on the blur detection mechanism of the eye and associated visual function changes and the potential mechanisms underlying myopia development and progression. To achieve this, the outcome measurements will be taken twice, first with MiSight contact lenses and then with 0.05 % atropine.