In vivo confocal microscopic features of normal limbus

To describe in vivo confocal microscopy (IVCM) features of the limbus in normal eyes as related to the palisades of Vogt's.

46 eyes of 29 consecutive volunteers were recruited in this observational study. A detailed examination by IVCM was performed in addition to a routine slit-lamp biomicroscopy. Size and density of corneal and limbal epithelial cells were measured and statistically analysed using SPSS version 8.0 software.

Anatomical and morphological features were noted between corneal and limbal cells. Size and density differences reached to significant levels (p<0.05). Different shapes of palisades of Vogt have been described clearly by confocal microscope. Cell-like structures were observed in the peripheral end of the palisades which might represent limbal stem cell crypts.

Laser IVCM can be used to establish the features of the normal limbus. The identified features demonstrate quantitative changes in the basal epithelium between the limbus and the central cornea and morphological differences between pigmented or non-pigmented studied subjects. Further studies should be performed to correlate with histology the possible crypts which were observed in this study.