Abstract
Purpose :
A clinical vision examination typically involves the assessment of high contrast visual acuity (HCVA) under photopic light levels; however, this does not necessarily reflect visual function under lighting conditions typical of night time driving. This study examines the associations between non-standard measures of visual function, including mesopic and glare-based measures, and self-reported vision-related night driving difficulties.
Methods :
The recently validated Vision and Night Driving Questionnaire (VND-Q) (Kimlin et al 2016) was used to quantify the driving difficulties of 72 licensed drivers (65.1 ± 8.7 years, 67% female) who identified themselves as having visual problems in low luminance or glare conditions when driving at night. Visual function measures included photopic (100cd/m2), mesopic (0.38cd/m2), high (90%) and low (10%) contrast visual acuity (VA), photopic and mesopic Pelli-Robson contrast sensitivity (CS), the Berkeley Glare Test and the Aston Halometer. The associations between measures of visual function and VND-Q scores were evaluated using regression analyses. Analyses were performed for the full sample of 72 participants and a subset of 29 participants who reported considerable night driving difficulties, yet had good photopic HCVA (better than 0.1logMAR).
Results :
For the full sample (n=72), the Aston Halometer was most strongly associated with VND-Q scores, where greater self-reported difficulties were associated with a larger glare halo area (p=0.001). Reduced high and low contrast photopic VA were also associated with greater self-reported difficulties (p=0.002; 0.011). For the subset of participants (n=29), mesopic CS was the only vision measure significantly related to self-reported VND-Q scores (p=0.004).
Conclusions :
The findings provide evidence that glare-based and low luminance measures should be incorporated into the vision assessment of patients reporting vision-related difficulties when driving at night, in addition to standard clinical testing.
This is an abstract that was submitted for the 2018 ARVO Annual Meeting, held in Honolulu, Hawaii, April 29 - May 3, 2018.