Radiological Study of Maxillary Sinus using CBCT: Relationship between Mucosal Thickening and Common Anatomic Variants in Chronic Rhinosinusitis.

INTRODUCTION Inflammatory diseases of the maxillary sinus favour the thickening of the sinus mucosa. Therefore, it might be possible to establish a radiological, pathological threshold of mucosal thickening. Furthermore, there is an association between common anatomic variants of the nose and maxillary mucosal thickening. AIM To define the pathological thickening of maxillary sinus mucosa and its association with the presence of common anatomic variants (concha bullosa, Haller's cell and accessory maxillary ostium). MATERIALS AND METHODS From March 2014 to February 2016, Two hundred patients underwent Cone Beam Computed Tomography (CBCT) of the paranasal sinus. We conducted this retrospective study of total 70 patients, 34 patients i.e., a total of 68 meatus-maxillary units (study group - those affected by Chronic Rhinosinusitis (CRS) and another 36 patients i.e., a total of 72 meatus maxillary units (control group - without symptoms of CRS). We assessed the degree of thickening of the sinus mucosa distinguishing between ≥ 2mm or ≤ 2mm, than we analysed the behaviour of the thickness in the study group and in the control group. Chi-Square test was used to compare mucosal thickening between study and control group and the presence of some common anatomic variants or closure of maxillary ostium. RESULTS In the study group we observed a clear association between maxillary mucosal thickening ≥ 2mm and CRS (p<0.01). We however, observed no association between the presence of common anatomic variations and thickening of the maxillary mucosa and between the presence of common anatomic variations and the study group. Instead, using a binary logistic regression, we observed a significant association (p<0.01) between closure of natural ostium of the maxillary sinus and mucosal thickening or between closure of natural ostium and study group. CONCLUSION We believe that a thickening of the maxillary mucosa ≥ 2mm and closure of natural maxillary ostium are statistically associated with CRS. The common anatomical variants do not seem to be associated with this condition.