If a drop of fluorescein is instilled into the conjunctival sac and the cornea is subsequently rubbed through the closed lids, a mosaic-like pattern of polygons appears in the epithelial layer of the cornea. This phenomenon, though certainly seen by many observers, has not been reported before.
The "Furchenbild" (groove pattern) of Fischer appears when a beam of light (preferably from a gas-laser), after having been reflected by the corneal surface, strikes an opaque diffusing screen.
Several arguments point toward an identical origin of both phenomena. If this is true, the fluorescein pattern is of value in explaining the reflectograms.