Background: The main objective of this long-term prospective local safety study was to evaluate endoscopic and histologic changes in nasal epithelium after 6-month treatment with triamcinolone acetonide (TAA). We describe here a method to measure quantitatively epithelium thickness. Results were compared with those seen with the use of cetirizine (an antihistamine) and another oral intranasal corticosteroid, beclomethasone dipropionate (BDP).
Methods: Patients were examined by an ENT specialist who first performed an endoscopic evaluation of the nasal cavities, assessing any morphologic abnormalities and the aspect of the mucosa. Biopsies were taken from the inferior turbinate before and after 24 weeks of treatment. Biopsies were immediately fixed in cold acetone (-20 degrees C) and embedded in glycolmethacrylate; sections of 2 microm were cut on an ultramicrotome. Morphometric evaluations were done in a blinded fashion by computerized image analysis to measure an epithelial area over a minimum length of 50 microm. The thickness was ascertained by the ratio of area to length.
Results: 1) For all three treatment groups, the nasal epithelium thickness decreased slightly from pretreatment to the end of treatment. 2) No statistically significant differences between the three treatment groups were found in epithelium thickness. 3) Macroscopically, nasal tissues in all treated groups were normal.
Conclusions: These results clearly indicate that long-term treatment with TAA has no atrophic effect on nasal mucosa.