Monochromacy

What it means

Complete color blindness, a complete inability to distinguish colors. Affected persons cannot perceive colors, but only shades of gray.

Rod monochromacy is the condition of having only rods in the retina. A rod monochromat is truly unable to see any color and can see only shades of gray.

Rare diseases that can present with this1

The range is how often this sign appears among people diagnosed with each disease — it is not a probability of having any of them. Many of these signs also occur in common, non-rare conditions. A sign on this page is a conversation to have with a clinician, not a conclusion.

Part of the broader category

Also called: Complete achromatopsia · Total colorblindness