Several studies have shown a number of histopathological alterations which occur in chronic rhinosinusitis. The nasal mucosa in paranasal sinus has been the primary site of these researches but very little about the bone alterations found in these diseases is known. AIM: Describe the histopathological alterations of the bone structure of the ethmoidal bulla in patients who have chronical rhinosinusitis. STUDY DESIGN: Clinical prospective. MATERIAL AND METHOD: Nineteen patients who had chronic rhinosinusitis were evaluated. Through light microscope, the bone trabeculae of etmoidal bulla were analysed as to the range of osteoid storage, the presence of osteoblasts and osteoclasts on the surface of the trabeculae, reabsorption, apposition lines and fibrosis between the bone trabeculae. The lamina propria was also analysed as to cellular elements, considering that inflammatory cells which release mediators that promote the bone lysis are found on this layer of the mucosa. The bone morphology was analyzed using electronic microscopy. CONCLUSION: Using scanning electronic microscopy, it was possible to observe the edges of the reabsorbed bone trabeculae more clearly. No case was considered normal, but no bone necrosis was observed. Through light microscope were observed: osteoids storage, osteoblasts agroupment, fibrosis and bone remodeling in about 90% of cases. Although the osteoclasts had not been seen, the bone reabsorption was present in 50% of cases. Deeper studies about inflammatory mediators on lamina propria in their actions on subjacent bone can clear up the physiopathology of chronic rhinosinusitis on the cellular level.
histopathology; ethmoidal bulla; chronic rhinosinusitis
