Figure 5.
H&E-stained section showing laser induced tissue damage. Higher magnification of rectangular area showing four zones identified in Figure 4A (A). Bar =250μ. TFZ showed intact architectural and cellular structures; the only morphologic abnormality was dark, shrunken, spindyloid to oval nuclei. Interstitium was normal and composed of compact collagen (B) The CNZ showed coagulation necrosis with retention of cellular outlines but loss of cytoplasmic and nuclear detail. Epithelial sloughing was evident. The interstitium on the left is normal; the interstitium on the right contains a dilated vein and loosely woven collagen due to plasma leakage from thermally damaged vessels (C). The primary changes in the MZ were edema (plasma leakage) of the interstitium, and uniformly dark shrunken nuclei. The MZ adjacent to the CNZ had sloughed epithelial cells and red blood cells in the lumens of glands. (D) The UZ is characterized by normal glandular and cellular architecture with open-faced nuclei (E). I = interstitium. Bar = 50μ (B–E).