Does blue-violet filtering affect contrast sensitivity?

The effects of blue-violet filtering (BVF) lenses on visual performances and more specifically on contrast sensitivity (CS) are still debated in the literature. BVF can affect positively the CS by reducing intraocular scattering, but also cause a reduction in light intensity, which contributes to the formation of the retinal image. The influence of BVF on CS is attributed to a balance among these effects. In this contribution, two different studies carried out with both blue-violet filtering ophthalmic and contact lenses are presented. Results showed a significant negative correlation between change in CS with BVF lenses with respect to clear lenses and the baseline CS with clear lenses. In the choice of a BVF, practitioners should consider that BVF is expected to produce a CS worsening in subjects showing a relatively high initial CS. On the contrary, subjects showing a relatively low initial CS are expected to show a CS improvement.