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

In Vivo. 2017 Nov-Dec;31(6):1081-1088. doi: 10.21873/invivo.11173.

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.

Keywords: Confocal microscopy; conjunctival microcysts; open angle glaucoma; three-dimensional analysis; trabeculectomy; transscleral aqueous humor outflow.

MeSH terms

  • Aged
  • Aqueous Humor / diagnostic imaging
  • Conjunctiva / diagnostic imaging*
  • Conjunctiva / physiopathology
  • Conjunctiva / surgery
  • Conjunctival Diseases / diagnostic imaging*
  • Conjunctival Diseases / physiopathology
  • Conjunctival Diseases / surgery
  • Female
  • Glaucoma / diagnostic imaging*
  • Glaucoma / physiopathology
  • Glaucoma / surgery
  • Glaucoma, Open-Angle / diagnostic imaging*
  • Glaucoma, Open-Angle / physiopathology
  • Glaucoma, Open-Angle / surgery
  • Humans
  • Intraocular Pressure
  • Male
  • Microscopy, Confocal / methods
  • Middle Aged
  • Trabeculectomy