Morphology of corneal nerves using confocal microscopy.
OBJECTIVE
The aim of the current study was to evaluate the distribution and morphology of corneal nerves as seen by means of white light confocal microscopy.


METHODS
This study analyzed images of corneal nerves that were obtained using the Tomey Confoscan slit scanning confocal microscope (40x/0.75 objective lens). The images were classified according to their location within the cornea. The objective and subjective evaluation of the images involved measuring, grading, or judging a number of parameters from both individual pictures and from each single nerve fiber within any image.


RESULTS
The in vivo observations made in this work are in agreement with those of previous histologic studies. The general scheme of corneal innervation is described as originating from thick and straight stromal nerve trunks that extend lateral and anteriorly and give rise to plexiform arrangements of progressively thinner nerve fibers at several levels within the stroma. From there, nerve fibers perforate Bowman's layer and eventually form a dense neural plexus just beneath the basal epithelial cell layer, which is characterized by tortuous and thin beaded nerve fibers interconnected by numerous nerve elements; nerve fibers from this plexus are known to be responsible for the innervation of the epithelium.


CONCLUSIONS
This study provides convincing evidence of the suitability of confocal microscopy to image corneal nerves, the only drawback being the limited resolution in terms of the differentiation of the ultrastructure of nerve bundles.
Oliveira-Soto
L
L
Department of Optometry and Neurosciences, University of Manchester Institute of Science and Technology, Manchester, United Kingdom.
Efron
N
N
D000328:Adult; D003315:Cornea / Q000294:innervation*; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008297:Male; D018613:Microscopy, Confocal; D009415:Nerve Net / Q000166:cytology; D009882:Ophthalmic Nerve / Q000166:cytology*