In vivo confocal microscopy of the bulbar conjunctiva

Abstract

Background: The aim of this work is to develop a
more complete qualitative and quantitative understanding
of the in vivo histology of the human bulbar
conjunctiva.
Methods: Laser scanning confocal microscopy
(LSCM) was used to observe and measure morphological
characteristics of the bulbar conjunctiva of 11
healthy human volunteer subjects.
Results: The superficial epithelial layer of the bulbar
conjunctiva is seen as a mass of small cell nuclei. Cell
borders are sometimes visible. The light grey borders
of basal epithelial cells are clearly visible, but nuclei
can not be seen. The conjunctival stroma is comprised
of a dense meshwork of white fibres, through which traverse blood vessels containing cellular elements. Orifices at the epithelial surface may represent goblet cells that have opened and expelled their contents. Goblet cells are also observed in the deeper epithelial layers, as well as conjunctival microcysts and mature forms of Langerhans cells.
The bulbar conjunctiva has a mean thickness of
32.9 1.1 mm, and a superficial and basal epithelial
cell density of 2212 782 and 2368 741 cells/
mm2, respectively. Overall goblet and mature
Langerhans cell densities are 111 58 and 23 25
cells/mm2, respectively.
Conclusions: LSCM is a powerful technique for
studying the human bulbar conjunctiva in vivo and
quantifying key aspects of cell morphology. The
observations presented here may serve as a useful
marker against which changes in conjunctival morphology
due to disease, surgery, drug therapy or
contact lens wear can be assessed.