CONTRAST SENSITIVITY AND TEAR QUANTITY IN COMMERCIAL BUS DRIVERS

ABSTRACT

The necessity for contrast sensitivity assessment to ensure safety among motorists and road users is ever present. Many road accidents can be credited to poor contrast sensitivity and poor tear quality among commercial bus drivers. The main purpose of this study was to determine the contrast sensitivity and tear quantity in commercial bus drivers in Benin City and compare to the average age related values in healthy individuals. An observational study was carried out on commercial bus drivers in Benin City. The contrast sensitivity and tear quantity of the patients was measured using the Pelli-Robson. The contrast sensitivity and tear quantity of a total of 50 bus drivers from selected motor parks was tested in this observational study. The sample included bus drivers that had been working at the motor park for over a year. The age range of bus drivers in this study was from 33 years to 71 years. The drivers mean age was 50.82 ± 8.6 years. The mean tear volume of the sample was found to be 19.86 μl ± 1.71 and 21.52 μl ± 1.72 for the right and left eye respectively. The mean contrast sensitivity values of the sample was found to be 1.76 log 11 ± 0.06 for the right eye and 1.75 log ± 0.84 for the left eye. The conclusion of this study showed that contrast sensitivity and tear quantity measured in the commercial bus drivers were significantly different from the average values previously obtained and there is a possibility for a relationship between contrast sensitivity and tear quantity. Keywords: Contrast Sensitivity, Tear Quantity, Pelli Robson Contrast Sensitivity Chart, Schirmer's Strip.