Could you define contrast sensitivity and at what stage in the progression of glaucoma it would most likely appear and cause problems driving?

Discrimination: Contrast sensitivity is the ability to discriminate more subtle changes in intensity usually of reading material. It is best highlighted by comparing magazine print with newsprint which has less contrast sensitivity. If you have glaucoma, this function will start to be impacted if you are having vision loss - the more, the greater. It will impact driving mostly at dawn and dusk.