In vivo findings of the bulbar/palpebral conjunctiva and presumed meibomian glands by laser scanning confocal microscopy

Objective: To report in vivo laser scanning confocal microscopic findings of the normal human conjunctiva and presumed meibomian glands and to investigate the potential application of this confocal microscope (HRT II Rostock Cornea Module) as a diagnostic device for normal and abnormal ocular surface structures. Method: Four healthy volunteers (51-, 49-, 31-, and 30-year-old men) participated in this study. The temporal bulbar conjunctiva, approximately 5 mm away from the limbus, and the upper tarsus conjunctiva of each patient were examined in vivo by a laser confocal microscope. Also, presumed meibomian glands beneath the tarsal conjunctiva were examined. Results: In all subjects, the in vivo laser confocal microscope obtained similar images. In the superficial epithelial cell layer of the bulbar conjunctiva, numerous bright nuclei were observed. We also observed many Langerhans cells with characteristic dendritic morphology and goblet cells with relatively homogeneous brightness ill the bulbar conjunctiva. Most interestingly, the palpebral conjunctival epithelium with invaginations or crypts was observed. In addition, weblike structures, presumably meibomian glands, were observed beneath the palpebral conjunctival epithelium. Conclusions: These results indicate that in vivo laser confocal microscopy can be used not only to visualize the bulbar conjunctiva but the upper tarsus conjunctiva and possibly subconjunctival meibomian glands. Further investigations of conjunctival and meibomian gland pathologies may further elucidate the potential of this device in clinical ophthalmology.