W9 Colour Vision 2

What is the standard normal CAD threshold for red-green and yellow-blue colour vision?

1 for both red-green and yellow-blue colour vision.

Can improved diabetic treatment control improve colour vision thresholds?

Yes, chromatic sensitivity can improve, and even return to normal thresholds with better diabetic control and management compliance.

What pattern of colour vision loss is typical in optic neuritis?

Significant loss in chromatic sensitivity in the affected eye, with losses in both red-green and yellow-blue colour vision.

How can colour vision assessment aid diabetes screening?

It can be used as a pre-screening tool, as prediabetics (high-risk) and diabetics show colour vision loss.

How does the CAD test help differentiate congenital and acquired deficiencies?

The CAD test allows to vary the stimulus size; when the stimulus size is larger the thresholds for acquired deficiency decrease but not for congenital deficiency.

What is a key early-stage use of colour vision testing in clinical environments?

Detecting monocular changes in colour vision as early biomarkers for retinal and systemic diseases.

When the stimulus intensity is at the phosphor limit what does this indicate in a CAD test result?

It indicates that the subject cannot detect even the most saturated stimulus presented on the display, showing severe colour vision loss.

What percentage of high-risk subjects had yellow-blue thresholds above the 2.5 sigma limit in the Kuwait study?

40% of high-risk subjects had yellow-blue thresholds above the 2.5 sigma limit.

Why is normal colour vision considered an indicator of retinal health?

Normal colour vision suggests proper functioning of the retina and optic nerve, suggesting no presence of disease.

Why is it important to have age-mathced colour vision limits?

Because colour vision changes with age; the normal thresholds for a 20y old are different to a 60y old. If you have unusually high thresholds for a 20y old, this may be indicative of early onset of an acquired disease.