Characterization of corneal edema by forward and backward second harmonic generation microscopy

摘要

We used second harmonic generation (SHG) microscopy to image and quantify the structural changes of bovine corneal edema. Forward SHG (FWSHG) and backward SHG (BWSHG) signals were simultaneously collected from normal and edematous bovine corneas to reveal their morphological differences. In SHG imaging, edematous corneas can be characterized by uneven expansion in the lamellar interspacing and increased lamellar thickness in posterior stroma (depth > 200 μm), while the anterior stroma composed of interwoven collagen architecture remained unaffected. Our work demonstrate the capability of SHG imaging in providing morphological information for the investigation of corneal edema biophysics and its potential application in the in vivo evaluation of advancing corneal edema.