Fig. 1
Structural patterns in control, preoperative and postoperative specimens of nasal mucosa (40×). a Normal ciliated pseudostratified epithelium on thin basement membrane (BM); the normal organization of the extracellular matrix with small blood vessels (V) is visible in the connective tissue underneath (a 1 ). b Preoperative mucosa showing the focal thickening of the basement membrane (BM) completely exposed to the external environment; epithelium is partially or completely missing with small residues of epithelial cells (EEC) flaking off. In the connective tissue (b 1 ) numerous inflammatory cells (IC) are immersed in an abundant amorphic substance (arrowheads) with few collagen fibers. c: Re-epithelisation of postoperative mucosa with the initial organization of the pseudostratified columnar epithelium (arrows) above a normal thickness basement membrane (BM). Some apoptotic cells are visible at the surface (arrowheads). Connectival side shows an evident recovery (c 1 ) with reduction of the inflammatory infiltrate and abundant amorphic substance