FIGURE 2.

Corneal stromal characterization 3 weeks after liquid nitrogen application. A,B, OCT and FFOCM cross sections of N₂‐injured cornea, respectively. Arrows show the presence of an opaque zone in corneal stroma. C,D, FFOCM images used to determine corneal stromal and total corneal thicknesses with the ImageJ software before (C) and 3 weeks after N₂ application (D). E,F, Corneal and stromal thicknesses were significantly higher (P = .0004) in injured vs control corneas 3 weeks after N₂ application. G,H, Histological analysis with hematoxylin and eosin staining of control and N₂‐injured corneas, respectively. I,J, Immunofluorescence analysis for collagen type III, in control vs N₂‐injured corneas. K,L, IVCM images of normal (K) and N₂‐injured (L) cornea showing the absence of blood vessel in corneal stroma. M,N, FFOCM en face images of normal (M) and N₂‐injured (N) cornea showing the absence of blood vessel in corneal stroma. O‐Q, CD31 negative staining in normal (O) and N₂‐injured (P) cornea. Positive CD31 staining was observed in corneal periphery (Q). Scale bars = 100 μm. Error bars = ±SEM. ***P < .001. FFOCM, full field optical coherence microscopy; IVCM, in vivo confocal microscopy; OCT, optical coherence tomography