A) The main purposes of this study are (i) to develop a related virtual reality (VR) environment in order to judge the nighttime driving ability under mesopic and under glare conditions (ophthalmologically healthy subjects and patients with incipient to intermediate cataract, i.e. opacities of the human lens, will participate in this study), (ii) to validate the above-mentioned VR environment with respect to a related on-road driving scenario under mesopic and glare conditions, (iii) to validate clinical photopic and mesopic contrast vision tests and glare tests with respect to the prediction of nighttime driving ability, (iv) to assess the test retest reliability of clinical photopic and mesopic contrast vision tests B) Background: An intact mesopic vision and a glare sensitivity within a normal range are essential pre-requisites for safe driving at nighttime (DOG \& BVA, 2011). Anderson \& Holiday (1995) have shown that (simulated) opacities of the refractive media (with only minor effects on daytime visual acuity) induce a pronounced impairment of contrast sensitivity under nighttime conditions. Especially under glare conditions by the headlights of traffic on the opposite lane or by stationary street illumination, an impairment of the mesopic vision may cause traffic hazards. The prevalence of impairments of the central visual acuity, the mesopic vision and the glare sensitivity is significantly higher for subjects being involved in nighttime traffic accidents (Lachenmayr, 1998). Furthermore, these impairments occur more frequently in aged drivers and are, among others, related to an increase of age-related media opacities (Aulhorn \& Harms, 1970, Babizhayev, 2003). Due to the demographic change, the relevance of nighttime driving ability is increasing in the next years since more and more aged employees will participate at the motorized traffic at night. The German Fahrerlaubnisverordnung (FEV i.e. driving license regulation) specifies pass/fail criteria with regard to mesopic vision and glare sensitivity. The luminance level during nighttime driving is usually between 0.01 and 1 cd/m\^2, and therefore can be attributed to the level of mesopic vision. However, over the last years, the attempt was made to introduce photopic contrast sensitivity test to diagnose nighttime driving ability (i.e. testing of contrast vision under daytime conditions without time consuming adaptation procedures). Current research aims at investigating the relationship between contrast tests under various luminance conditions (Wilhelm et al, 2013). It is questionable, whether photopic tests are at all reliable predictors with regard to nighttime driving (Gramberg-Danielsen et al., 1984, Hertenstein et al., Graefe´s Archive of Ophthalmology, 2016).
See this in plain English?
AI-rewrites the medical criteria so a patient or caregiver can understand them. Always confirm with the trial site.
Pass/fail rate (i.e. ratio of "no. of subjects passed" by "total no. of participants") with respect to a vision-related driving ability test
Timeframe: From date of "first subject in" to date of "last subject out", i.e. over an 18 months period