ABSTRACT
PURPOSE: To describe corneal and conjunctival epithelial changes in various ocular surface disorders with a new in vivo confocal microscope (Corneal HRT II module) and to compare these results with those obtained by immunohistology on impression cytology specimens. METHODS: In this study, we investigated 36 eyes of 18 patients with ocular surface diseases such as corneal epitheliopathy induced by ocular rosacea (five patients), keratoconjunctivitis sicca related to tear evaporative condition in Meibomian gland dysfunction (eight patients), or tear-deficient dry eye in Sjögren's syndrome (five patients). In vivo confocal microscopy imaging (Heidelberg Retina Tomograph II Rostock Cornea Module) and impression cytology of the cornea and/or conjunctiva were performed. The images were analyzed for epithelial cell morphology at nuclear and cytoplasmic levels, in the cornea and the conjunctiva, number of goblet cells and their possible presence within the corneal epithelium, corneoconjunctival junction at the limbus, and density and presence of inflammatory cells within both epithelia. RESULTS: Images obtained consisted of two-dimensional 400x400 microm optical sections oriented parallel to the surface of the eye and compared with impression cytology. Conjunctival and corneal epithelia showed dramatic changes in ocular surface disease. In keratoconjunctivitis sicca, we found squamous metaplasia, inflammatory cell infiltration, goblet cell depletion, as well as a nuclear snake-like chromatin pattern. In rosacea associated with corneal epitheliopathy, a corneal conjunctivalization (goblet cells together with conjunctival epithelial cells within the corneal epithelium layer) was found. The images provided by this technique are in excellent correlation with the findings using impression cytology. CONCLUSION: The HRT II in vivo confocal microscope facilitates the study of both central and peripheral ocular surface epithelia compared to first-generation confocal microscopy devices. In vivo confocal microscopy, showing corneal and conjunctival epithelial structures in the live eye at the cellular level, is likely to open up a new promising way to investigate ocular surface involvement in complex diseases, providing a new insight on corneal and conjunctival disorders in the future.
Subject(s)
Conjunctiva/pathology , Conjunctival Diseases/pathology , Corneal Diseases/pathology , Epithelium, Corneal/pathology , Microscopy, Confocal , Epithelium , HumansABSTRACT
This article summarizes our current knowledge on two types of retinal diseases: hereditary retinal degeneration and wet aged-related macular degeneration. Our understanding of retinal physiopathology in hereditary retinal degeneration and the successful experimental therapeutic results on animal models call for a new approach to these patients to prepare future clinical trials. Longitudinal follow-up of the functional alteration rhythm based on international standards and by expert centers is an essential prerequisite to including these patients in future clinical trials. Creating international databases that include data on follow-up using electrophysiological, psychophysical and morphological analyses would require standards defining how each of these procedures should be carried out. Furthermore, the relevance and value of the various examinations would then be evaluated in a longitudinal manner. The repeated use of these procedures in the various centers would bring to light any limitations these techniques may have for use in prospective studies. Continuous re-evaluation of these investigative techniques will therefore be necessary, a crucial factor in the preparation of multicenter clinical studies. The inclusion of patients phenotyped at different centers would require that certification procedures be set up for these centers. A great leap forward, clinical trials on new antiangiogenic approaches for the treatment of neovascular AMD are currently underway. The reasons for the switch between the neovascular and atrophic forms of AMD are as yet unknown, but these new approaches are based on the events that occur sequentially during the angiogenic response.