Figure 1.

Spatial distribution of photoreceptor cell death 24 hours following light exposure in RHO T4R mutant dogs. (A) Grading system used to map the incidence of TUNEL-positive cells in the ONL. (B₁–B₄, C) Schematic color-coded representation of grades of TUNEL-labeling in retinal sections extending from the edge of the optic nerve head to the superior, inferior, nasal, and temporal ora serrata: (B₁–B₄) four RHO T4R dogs exposed to decreasing doses of light by means of a Ganzfeld stimulator; (C) a RHO T4R dog exposed to a series of overlapping fundus photographs. LE, left eye; RE, right eye.