The Hudson-Stahli line. III: Observations on morphology, a critical review of aetiology and a unified theory for the formation of iron lines of the corneal epithelium.

Observations as to the morphology, position and orientation of the Hudson-Stahli line are presented, based on the slit-lamp biomicroscopic examination of the eyes of six hundred and forty-four subjects. The origin of the pigments in the Hudson-Stahli zone and other corneal epithelial lines is reviewed, the evidence for either tear film dynamics or epithelial dynamics influencing the typical configuration is discussed and a unified theory for the formation of corneal iron lines is presented.