Background: Although a CT scan is often performed after functional endoscopic sinonasal surgery (FESS) in patients with chronic rhinosinusitis, its role hasn`t been firmly established. The goal of this study is to investigate the correlation between symptoms and CT findings before and after FESS for chronic rhinosinusitis. In addition, the interobserver agreement for both sinonasal aerial volumetry and CT score is assessed.
Methods: Thirty-three patients surgically treated for chronic rhinosinusitis were included in this prospective study. Conventional and modified Lund-Mackay scores and sinonasal volumetry were determined by two radiologists before (M0), at 3 months (M3) and 1 year (M12) after surgery. The symptoms were evaluated by the 22-item SinoNasal Outcome Test (SNOT-22).
Results: Change of SNOT-22 and air volume were significantly correlated between M0 and M12, but not between M0 and M3, for both readers. Compared to other scores, volume had the best intraclass correlation coefficient and reproducibility, according to the Bland-Altman analysis. No correlation was found between SNOT-22 and CT scores before and after surgery, except between M12 and M0 for one reader.
Conclusion: The correlation between CT scan and symptoms is low or absent. The measurement of sinonasal air volume is best correlated with the symptoms after surgery, with the best inter-observer agreement.