Three-dimensional Laser Scanning Confocal Analysis of Conjunctival Microcysts in Glaucomatous Patients Before and After Trabeculectomy

Abstract

Background/Aim: In glaucoma, conjunctival epithelial microcysts (CEM) have been extensively investigated by means of laser scanning confocal microscopy. In the present case series, we examined eight glaucomatous patients undergoing trabeculectomy to obtain a 3-dimensional (3-D) characterization of CEM. Materials and Methods: Image acquisition was performed in z-scan automatic volume mode by Heidelberg Retina Tomograph III/Rostock Cornea Module and a series of 40 images of 300×300 μm (384×384 pixels) to a maximum depth of 40 μm were acquired throughout the upper bulbar conjunctiva before (at the site planned for surgery) and eight weeks after trabeculectomy. The 3-D volume tissue reconstruction with maximal size of 300×300×40 μm was obtained. Results: In the enface view, CEM appeared as empty, optically clear, round or oval shaped sub-epithelial structures. The 3-D spatial reconstruction showed microcysts as oval-shaped and optically clear elements, which were close, but clearly separated from the epithelium. CEM were embedded in the extra-cellular spaces and located about 10 μm below the epithelial surface. After trabeculectomy, CEM increased density and area especially along the horizontal axis. Conclusion: The 3-D in vivo confocal reconstruction of CEM permits for better clarification of their microscopic anatomy and patho-physiological significance, confirming their involvement in AH flow through the bleb-wall after filtration surgery for glaucoma.