12 April, 2021

Driver eyesight – the dangers of poor vision

Sadly, it happens all too often but when we hear about motor vehicle accidents on the road, we typically question whether speed, drugs or alcohol were a factor in the accident. Driver eyesight is typically overlooked. According to Optometry Australia’s 2020 Vision Index report, one in five middle aged Australians (35-54) find it difficult to read road signs while driving during the day while a further 22% state they squint to see better while driving at night.

Good eyesight is essential for safe driving. Our vision helps us see and respond to the environment including other vehicles, signs, signals, pedestrians and hazards.

Vision requirements for safe driving
Visual functions that contribute to good vision which are important for safe driving include:

Visual acuity
Visual acuity relates to the clarity or sharpness of your eyesight, measured by your ability to identify letters or numbers on a standardised eye chart from a specific viewing distance.

You need to be able to meet the visual standards, with or without corrective lenses as set out by your state or territory authorities.

Visual fields
A visual fields test is conducted to detect blind spots in the peripheral vision which can be an indicator of an eye disease or neurological disorder. During a visual fields test, your optometrist will assess your horizontal and vertical range. If vision loss is significant, you may not meet the national eyesight driving standards.

Contrast sensitivity
Contrast sensitivity refers to the ability to distinguish an object against a background even when it is not clearly outlined or prominent. Reduced contrast sensitivity is common with ageing and can be a symptom of cataracts, glaucoma or diabetic retinopathy. It can make it difficult to see in low light such as night time driving.

Eye movements
Eye movements enable your eyes to fixate and track objects by stabilising images on the retina, allowing clear vision despite your own movements and those of objects around you. Eye movement can be impacted by conditions such as stroke and brain injury which can result in impaired vision.

Depth perception
Depth perception is the ability to perceive your surrounds in three dimensions (3D) and to judge the distance of objects. When driving, depth perception allows you to judge distances between objects. It relies on the brain receiving information from both eyes. People relying on vision from only one eye will need to rely on other visual cues to gauge depth and their depth perception is generally less accurate.

What should I do if I have vision concerns?
Whether you notice sudden changes to your vision or they creep up on you gradually, it’s important to speak with your optometrist who can conduct a thorough assessment of your visual health. Driving while vision impaired poses a risk to you and those around you.

Your optometrist may prescribe corrective lenses to help you while driving or offer other solutions such as eye exercises to help improve your vision.

For those over the age of 40, it’s recommended to have an eye test every two years while those over the age of 75 should get tested yearly. Regular eye exams are important in maintaining good eye health and for the early detection of eye disease.

If you have concerns about your vision please make an appointment with your local EyeQ optometrist.