Fig 3. Serial epithelial changes at the nasopharyngeal end of the rat ET after ETBD.

A 15x power field view and 50x power field sections are shown in the left and right columns, respectively. The epithelial cells were damaged (arrow) immediately after ETBD. At 1-week post-dilation, the morphology of the epithelial cells had recovered but goblet cells were not seen (black arrowhead). At 4- and 12-weeks post-dilation, the columnar epithelium and goblet cells had fully recovered (asterisk). H&E stain, scale bars represent 50μm.