The Hudson–Stahli line is a line of iron deposition lying roughly on the border between the middle and lower thirds of the cornea.
It is generally horizontal, with possible mild downward trend in the middle.
The Hudson–Stahli line is not associated with any pathology calling for clinical intervention.
Formation of the line may depend upon the rate of tear secretion.
[2] However, the Hudson–Stahli line can be enhanced in hydroxychloroquine toxicity.