Table 1 of Bhatia, Mol Vis 2016; 22:898-916.

Table 1. Summary of past studies.

Study Authors Sample Size Cells Areas of Retina Measurements Methods Study Findings
Ts’o and Friedman [9] 10 eyes RPE 5 concentric regions around the macula Cell density
Cell area RPE flatmounts were bleached; cells counted manually; cell area determined by dividing the total retinal area by # of cells - RPE cell density decreases in the posterior pole with age
- equatorial RPE cell density increased with age cell area decreased with age in posterior pole, increased in equator and periphery
Dorey et al. [10] 30 eyes PF
RPE Macula
Equatorial Cell density Fixed and embedded eyes; cells counted manually from radial sections - RPE density decreased in posterior pole; not quantified
- No changes with age in equator
Gao and Hollyfield [11] 35 eyes GC**
RPE Fovea
Peripheral Retina Cell Density Tissue was embedded and sectioned; cells counted by one observer - No age related changes in foveal RPE cell density
- Peripheral RPE loss 14 cells/mm2/year
- RPE density=5531 - 14 X age (years), Foveal RPE density 63% higher than periphery
Watzke et al. [7] 20 eyes RPE Fovea
Temporal Posterior pole
Peripheral retina Cell density
Cell area
Form factor Polymegathism RPE flatmounts were bleached; cells counted manually - no age effect on cell density or cell area found in any of the regions
- RPE cells of fovea and temporal posterior pole were more hexagonal in younger eyes
Panda-Jonas et al. [5] 53 eyes PR*
RPE Fovea
Outer-periphery Cell Density 25 biopsy specimens of the retina and RPE; Cells were counted from photographs - Total RPE cell density decreased by 0.3% per year
- fovea (4,220±727 cells/mm2)
- mid-periphery (3,002±460 cells/mm2)
- outer periphery (1,600±411 cells/mm2)
Harman et al. [8] 38 eyes RPE Whole Retina Cell Density Whole-mounted RPE; cells counted by manual tracing - No age effect on cell density found in any regions of retina
Del Priore et al. [6] 22 eyes RPE 4 concentric regions around the fovea Cell Density
# Apoptotic cells RPE flatmounts were TUNEL stained and counted - Total RPE cell density decreased by 0.23% per year
- RPE density (cells/mm2)=4,890×11.3 (age)
- Significant change in the density of RPE cells only seen in Zone 4
- Cell density decreased in the RPE w/increased distance from fovea
- Zone 1 (4980±90 cells/mm2); Zone 2 (4857±75 cells/mm2)’ Zone 3 (4068±207 cells/mm2); Zone 4 (4024±137 cells/mm2)