| The study tries to assess visual performance of RGP multifocals, soft bifocals, and RGP monovision under mesopic conditions. 32 subjects between the ages of 42 and 65 years participated in this study. All subjects participated in a screening for their visual adaptive system using the dark adaptometer. Low (10%) and high (90%) contrast acuities were recorded using the Bailey-Lovie chart. Measurements of contrast sensitivity using the Vistech 6500 system and glare sensitivity using the Brightness Acuity Tester were made. Pupil size was measured under low and high luminance levels. Near visual task performance was also assessed. An index of visual performance based on contrast sensitivity established RGP multifocals to have the best visual performance at an index of 0.985, soft bifocals with an index of 0.659, and monovision with an index of 0.595. The results of our study conclude that RGP multifocals perform best under mesopic light levels. Overall, our results show that all our subjects wearing RGP multifocals, soft bifocals, monovision have good contrast sensitivity, satisfactory low and high contrast acuity and reduced glare sensitivity. |
