[Variations of the microstructure in human limbus by confocal microscopy in vivo]

To demonstrate the variations in the niche of limbal stem cells and the limbal basal epithelial cells in vivo by confocal microscopy.

One hundred and twenty eyes of 120 healthy subjects were enrolled in this study after a routine slit-lamp examination. They were divided into four groups according to the age: group A (0-), group B (20-), group C (40-) and group D (60 - 79). Confocal microscopic examination in vivo was performed and the images of the inferior limbus were recorded. The morphologic features of each group were analyzed and the average size of limbal basal epithelial cells of each group were measured.

The morphologic features of limbus varied among groups. 96.7% (29/30) of group A showed clear Vogt Palisades, while 3.3% (1/30) showed no Vogt Palisades. 96.7% (29/30) of group B also showed clear Vogt Palisades, while 3.3% (1/30) showed no Vogt Palisades.70.0% (21/30) of group C showed clear Vogt Palisades, while 13.3% (4/30) showed atrophic Vogt Palisades and 16.7% (5/30) showed no Vogt Palisades at all. 33.3% (10/30) of group C showed clear Vogt Palisades, while 10.0% (3/30) showed atrophic Vogt Palisades and 56.7% (17/30) showed no Vogt Palisades at all. The average size of limbal basal epithelial cells in each group was (9.89 +/- 1.12), (10.65 +/- 1.45), (10.70 +/- 1.39) and (12.22 +/- 1.42) microm in sequence.

There is variations in the microenvironment of niche in human limbus. Meanwhile, limbal basal epithelial cells showed different quantity and cell size, demonstrating varied proliferative potential.