gms | German Medical Science

The corneal epithelium, which is the most important part of the corneal diffusion barrier, showed differences of permeability to watery, ionic substances as natrium fluorescein (NaF). Diabetic patiens for example showed a significant increase of permeability. The natrium fluorescein penetrates also the area of micro erosiones and pathologic changed cells. But there is some difference of opinion in literature about of the nature of the penetrating process. Most authors means the stainig is due to drop out of cells and pooling of fluorescein in the foot print. Other believe the fluorescein fills the intercellular spaces. To analyze this phenomena and differences in epithelial wound healing after staining with NaF present only confocal slit scanning microscopes and fluophotometer were used.

The Heidelberg Retina Angiograph with the Rostock Cornea Module was used to confocal laser scanning fluorescence microscopy (contact / non contact) of the corneal epithelial micro structures with lateral resolve of 1mm. In the state of contact microscopy there is a exact digital information of the depht of the laser focus plan in the epithelium in a range of 1-5 mm. The autofluorescence measuring also is possible.

The slides of fluorescence and red-free microscopy showes the intercellulare structure with stained nucleus and changes cell surfaces und bouderies in different magnification. The penetration profile of NaF could be measured over a long time with high resolve.

The confocal laser scanning fluorescence microscopy described allowed good visualization of the spatial arrangement of the corneal epithelial cells in autofluorescence and after staining with NaF. Combined with morphometric methods, the 3D-analysis of the state of the cornea yields a quantitative description of wound healing processes and the NaF penetration phenomena in different pathologic changes of the epithelium.