The Impact of Ocular Diseases on Driving: a Prospective Study
Condition: Macular Degeneration; Glaucoma
MeSH terms: Macular Degeneration
Study type: Observational

Summary: 
      The purpose of the study was (1) to determine thresholds for discriminating speed in
      peripheral fields of patients with dry AMD and (2) to examine the driving skills of licensed
      drivers with early dry AMD using a driving simulator and to investigate how their healthy
      counterparts perform on the same driving tasks. We hypothesized that speed discrimination may
      be better in patients with dry AMD than in healthy control subjects.
    

Detailed description: 
      This observational study has two goals:

        1. to establish if patients affected by dry AMD have a different speed discriminating
           threshold using peripheral vision fields than their healthy counterparts.

        2. to determine if the driving skills of AMD and glaucoma patients differ from healthy
           controls.

      Two tasks will be used: 1) A speed discrimination test. (Glaucoma patient are not asked to
      perform this task as it assesses the peripheral visual fields, which is affected by the
      disease.) 2) A driving simulation session. Participant will undergo both tests on the same
      day, no later than a month after the initial recruitement visit.

      For both diseases, patients will be compared to healthy controls matched for age and gender,
      but also to a younger control group. The latter group was added in order to take into account
      the normal aging impact on driving skills (visual and cognitive).

      Our hypothesis is that AMD patient will show a better speed discriminating threshold than
      matched control and maybe better or equal to the younger control groups. We also hypothesize
      that driving skills involving peripheric speed awareness, such as passing another car, will
      be enhanced in the AMD group when compared to glaucoma patients and age-matched control
      group.
    

Intervention name(s): Speed discrimination test; Driving simulation
Intervention type(s): Other; Behavioral
Intervention description(s): The participant has to stare in the middle of two screens, i.e the reference screen and the test screen. Dots are moving from the center to the edge of the screens at different speeds. The participant is forced to determine if the dots of the test screen are moving faster or slower than the reference screen.
The test is designed in Psychtoolbox3. Data analyses performed using MATLAB. Two-alternative forced choice paradigm.; 25 km simulated car driving session. The participant is seated in the driver compartment of a real car featuring all the actual components (steering wheel, pedals regulating speed and brakes). He is instructed to respect road regulations as well as safety rules and must perform some driving manoeuvres, such has turning at intersections, stopping when necessary, passing another car, etc.
Software Drive 3.0 by Systems Technology Inc., Hawthorne, California, USA. Magnetic head tracker (Flock of Birds, Ascension Technology Corporation, Burlington, Vermont, USA).
A fixed-base driving simulator. 2 driving scenarios: a practice (10 minutes) and a main scenario including rural and urban sections (35 minutes).
Observational model: Other
Time perspective: Prospective
Sampling method: Non-Probability Sample
Study population: 
        Patients (with glaucoma or AMD) were recruited from the Centre Universitaire
        d'Ophtalmologie (CUO), Saint-Sacrement Hospital in Quebec City.

        Participants in control groups are residents of Quebec City.