Older drivers' self-reported vision-related night-driving difficulties and night-driving performance

Visual function correlates of self-reported vision-related nighttime driving difficulties

PURPOSE

To investigate the visual function correlates of self-reported vision-related night driving difficulties among drivers.

METHODS

One hundred and seven drivers (age: 46.06 ± 8.24, visual acuity [VA] of 0.2logMAR or better) were included in the study. A standard vision and night driving questionnaire (VND-Q) was administered. VA and contrast sensitivity were measured under photopic and mesopic conditions. Mesopic VA was remeasured after introducing a peripheral glare source into the participants' field of view to enable computation of disability glare index. Regression analyses were used to assess the associations between VND-Q scores, and visual function measures.

RESULTS

The mean VND-Q score was -3.96±1.95 logit (interval scale score: 2.46±1.28). Simple linear regression models for photopic contrast sensitivity, mesopic VA, mesopic contrast sensitivity, and disability index significantly predicted VND-Q score (P<0.05), with mesopic VA and disability glare index accounting for the greatest variation (21 %) in VND-Q scores followed by photopic contrast sensitivity (19 %), and mesopic contrast sensitivity (15 %). A multiple regression model to determine the association between the predictors (photopic contrast sensitivity, mesopic VA, mesopic contrast sensitivity, and disability index) and VND-Q score yielded significant results, F (4, 102) = 8.58, P < 0.001, adj. R2 = 0.2224. Seeing dark-colored cars was the most challenging vision task.

CONCLUSION

Changes in mesopic visual acuity, photopic and mesopic contrast sensitivity, as well as disability glare index are associated with and explain night driving-related visual difficulties. It is recommended to incorporate measurement of these visual functions into assessments related to driving performance.

Safety potential of crash avoidance features, improved headlights, and V2V-enhanced technologies for older drivers

INTRODUCTION

Age-related changes and frailty are among the reasons that older drivers are overrepresented in certain crash types. Vehicle safety features that address these crash types may therefore deliver greater safety benefits for older drivers than for other age groups even though they are designed for the general population.

METHODS

U.S. crash data from 2016-2019 were used to estimate the proportion of crash involvements and fatal and nonfatal driver injuries for older (70 years old and above) and middle-aged (35-54 years old) drivers from crash scenarios to which current crash avoidance features, improved headlights, and forthcoming vehicle-to-vehicle (V2V)-connected intersection-assistance features could be relevant. Risk ratios were then calculated to determine the relative benefits of each technology for older drivers compared with middle-aged drivers.

RESULTS

Combined, these technologies were potentially relevant to 65 % of older driver and 72 % of middle-aged driver fatalities during the study period. Intersection assistance features showed the most promise for older drivers. Such features were potentially relevant to 32 % of older driver crash involvements, 38 % of older driver injuries, and 31 % of older driver fatalities. Intersection assistance features were significantly more likely to be relevant to older driver deaths than middle-aged driver fatalities (RR, 3.52; 95 % CI, 3.33-3.71).

CONCLUSIONS

Vehicle technologies have the potential to substantially reduce or mitigate crashes and the injuries that they cause for everyone, but the potential safety impact of each technology varies by driver age because different age groups are over- or underrepresented in specific crash scenarios.

PRACTICAL APPLICATIONS

With the older driver population growing, these findings underscore the need to bring intersection assistance technologies to the consumer market. At the same time, everyone stands to benefit from currently available crash avoidance features and improved headlights, so their use should be promoted among all drivers.

Effectiveness of SMILE Combined with Micro-Monovision in Presbyopic Patients: A Pilot Study

Binocular summation along all defocus range after a micro-monovision procedure has scarcely been studied. The aim of this pilot study was to evaluate the efficacy of SMILE combined with different levels of micro-monovision in presbyopic patients and to assess the binocular summation effect on contrast sensitivity defocus curves (CSDC) at the 6-month follow-up. Efficacy was assessed on the basis of visual acuity (VA) and stereopsis at far, intermediate, and near distances. Patient-reported outcomes (PROs) and binocular CSDC were also evaluated. Six patients completed the study with a programmed median anisometropia of 0.81 Diopter. The median binocular uncorrected VA was better than 0 logMAR at the three evaluated distances, and stereopsis was not impaired in any patient, achieving a median of ≤119 arcsec at any distance. CSDC increased binocularly after surgery, significantly in the range of -2 to -3 D (p < 0.05). No clinically relevant changes were observed in PROs compared with the preoperative period, and all patients achieved spectacle independence at intermediate/near distance and were likely or very likely to undergo the same surgery. In conclusion, micro-monovision with SMILE could be an effective procedure, with results that might be comparable to other laser correction techniques specifically designed for presbyopia correction.

Research Regarding Different Types of Headlights on Selected Passenger Vehicles when Using Sensor-Related Equipment

Statistical surveys show that the majority of traffic accidents occur due to low visibility, highlighting the need to delve into innovative car lighting technologies. A car driver must not only be able to see but also to be seen. The issue of headlight illumination is vital, especially during the dark hours of the night. Therefore, the focus of this article is determining the range of visibility of dipped (low-beam) headlights under specific experimental conditions. We also designed a methodical guideline aimed at identifying the distance at which dipped headlights illuminate the road while a vehicle is in motion. Research conducted on various classes of road confirmed that the Hyundai i40 is best used on higher-class roads, while the Dacia Sandero is better used on lower-class roads due to the shape and spreading out of its light cone. Furthermore, the pros and cons of the distribution of light cones on several classes of road are presented. Sensor-related equipment was also used to investigate light beam afterglow. In particular, an LX-1108 light meter was applied to determine the obstacle illumination intensity, the properties of which enable recording of low lighting values, and a DJI Mavic AIR 2 unmanned aerial vehicle (UAV; drone) was utilized to record the data related to the location of the examined vehicle, as well as light afterglow at night; relevant data evaluation was carried out using Inkscape software.