Real-time mapping of the subepithelial nerve plexus by in vivo confocal laser scanning microscopy

Aim To produce two-dimensional reconstruction maps of the subepithelial nerve plexus (SEP) in living cornea by in vivo laser scanning confocal microscopy in real time. Methods In vivo confocal laser scanning microscopy (Heidelberg Retinal Tomograph II in conjunction with the Rostock Cornea Module) was performed on normal eyes (n=6) and eyes after laser-assisted in situ keratomileusis (LASIK) (n-4). Source data (frame rate 30 Hz) were used to create large-scale maps of the scanned area in Automatic Real Time composite mode. The algorithm aligns single live images onto the previously mapped composite image using landmark feature-based image processing. Results Real-time mapping of the SEP was performed on a large-scale area up to 3.2x3.2 mm (3072x3072 pixels) in healthy subjects and in post-LASIK patients. Two-dimensional structures of the SEP were imaged in all 10 eyes. Mapping quality as well as acquisition time were dependent on subject compliance and examiner experience. Conclusion The described method permits real-time in vivo mapping of the SEP, thus providing the necessary basis for statistically robust conclusions concerning morphometric plexus alterations.