Computed Tomography Scans as an Objective Measure of Disease Severity in Chronic Rhinosinusitis

Abstract

Objectives: A truly objective method of measuring disease severity in CRS does not exist. We evaluated computed tomography (CT) scans of chronic rhinosinusitis (CRS) patients using a novel 3-D computerized method and compared them to a 2-D objective computerized analysis of a single coronal slice through the osteomeatal complex (OMC), and subjective methods including Lund-Mackay and Zinreich’s modification of Lund-Mackay. Methods: Forty-six adults with symptoms and endoscopy confirmation of CRS underwent CT examination and received a triamcinolone injection, followed by CT scan 4-5 weeks later. Analyze software determined the 3-D total volume of inflammatory mucosal thickening in all sinuses. The triamcinolone injection served as a tool to determine each method’s sensitivity to a treatment intervention. Results: The Lin’s concordance class correlation (CCC) of the OMC method revealed the best correlation to the 3-D volumetric computerized values (0.915), followed by the Zinreich (0.904) and Lund-Mackay methods (0.824). Post-treatment results demonstrated that both the OMC (0.824) and Zinreich’s (0.778) methods had strong agreement with the 3-D volumetric methods and were very sensitive to change, whereas the Lund-Mackay (0.545) only had moderate agreement. Conclusions: Computerized CT analysis provides the most comprehensive, objective, and reproducible method of measuring disease severity and is very sensitive to change induced by treatment intervention. A 2-D coronal image through the OMC provides a valid, user-friendly method of assessing CRS and is representative of CRS severity in all sinuses. Zinreich’s subjective method correlated well overall, but Lund-Mackay lagged behind in disease representation and sensitivity to change.