Influence of coloured stimulus on the mesopic pupillary diameter

Abstract

Abstract Purpose To know and quantify the effects of the coloured stimulus in the mesopic pupilar diameter. Methods 132 binoculars measures were analyzed in 5 people of ages ranging between 24 and 31 years old, within mesopic conditions and a time of adaptation to the darkness of 15 minutes. The pupilometer utilized was the Power Refractor II from PlusOptix. The interfered filters of 450, 510 and 600 nm were from EDMUND Optics trademark, were placed in front of a photographic flash Metz (60CT‐1) with a circular opening of 7 mm of diameter. The patients maintained the fixation on the infrared sensor of pupilometer placed to 1 meter of distance whereas the flash was placed to 2 meters of distance, both instruments in line with the midpoint of the eyes of the patient. Results There have not been significant differences between both eyes. The average of the maximum values of the mesopic pupilar diameter was of 5,93± 0,13mm in a without filter condition; 6,10±0,03mm for the filter of 450nm; 6,03±0,08mm for the filter 510nm; and 5,84±0,03mm for the filter of 600nm. The average of the change to mesopic pupilar stimulation without filter was of 2,61±0,53mm; with 600 filter, it was of 2,06±0,51mm; with 510 filter, it was of 2,21±0,41mm and with 450 filter it was of 2,12±0,32mm. These results point out a greater reaction to mesopic pupilar with the filter of 510nm and minor reaction with filter of 600nm. The stimulus of wavelength of 510nm in mesopic condition is the one that provides major pupilar contraction, whereas, in contrast, the stimulus of 600nm is the one that provides less reaction to pupilar. Conclusion The mesopic pupilar diameter varies in regarding with wavelength of the stimulus.