Figure 3. Temporal and spatial course of photoreceptor loss after light exposure. Hematoxylin and eosin–stained retinal cross-sections of control retinas (lower row) and of the left (dilated) eyes from animals photoexposed under circular (left two columns) or linear (right two columns) bulbs. Images were taken from the mid-dorsal and midventral retina. A-D: animals processed at 0 h, E-H: 7 days, I-L: 1 month, M-P: 3 months, Q: 6 months, R, S: 9 months, T: 12 months after light exposure (ALE) and control animals. U-V represents control animals. Photoreceptor loss is observed in all sections but in D (animals processed 0 h ALE; ventral retina), where the retinal structure is conserved and is similar to control animals. Photoreceptor loss was always more severe in the dorsal retina. During the first 3 months ALE, retinal damage was more drastic in the animals exposed to circular bulbs; however, from this time point onwards, it was similar in all animals (M-P). Six or more months ALE (Q-T), vascular complexes (arrowheads) were observed in the subretinal space, sometimes connected to vessels that ran vertically in the retina and that are surrounded by nonpigmented cells (arrows). The scale bar represents 100 µm.