If they've got impaired function, you might opt not to use contrast.

Not enough pop stars use their comeback to draw attention to how a biotin deficiency can lead to hair-loss, dry eyes and impaired function of the liver.

Mutations of this gene lead to reduced beta cell mass or impaired function.

The level of physical impairment must be significant, such as brain injury or total body impaired function (as in the case of cerebral palsy).

Most of the impaired function returns to normal shortly after the intake of vitamins returns to normal.