LATE-BREAKING ABSTRACT: A new, easy to use computed tomography based scoring system for sinus disease in cystic fibrosis: Validated with acceptable inter- and intra-rater reliability

Background: There is no CF specific CT based scoring system for sinus disease in CF. Aim/Objective: We propose a scoring system to quantify severity of CF related sinus disease. Design/Methods: After IRB approval, we validated a scoring system in 197 patients with CF ages 8-30 years (mean 17±6.3) and 120 aged matched non CF controls. CT were blindly interpreted by a pulmonologist, otolaryngologist, and a neuro-radiologist twice. Parameters:maxillary opacification and nasal cavity obstruction scored on an ordinal level (0-3) with 0=normal, 1=mild ( 66%), while nasal wall displacement, Uncinate process absent/demineralized, and Mucocelewere scored as 1=yes, 0=no. Intra-rater and inter-rater reliabilitywas measured using criteria derived from Landis& Koch (1997):0.0-0.2= poor, 0.21-0.4=fair, 0.4-0.6=moderate, 0.61-0.8=strong, and 0.81-1.0=excellent agreement. Results: Intra-Rater Reliability: In CF cohort, reliability for the 10 CT categories across the three raters ranged 33%-100%. Two (6.6%) were moderate and 27 (90%) were strong to excellent reliabilities. In control group, 2 (6.6%) were strong and 28 (93.3%) were excellent. Inter-Rater Reliability: in CF cohort, 10 CT categories across the three raters ranged from 10%-92%. Strong-excellent reliability (≥60%) were noted in 11 (36.3%), moderate in 7 (23.3%), fair in 11 (36.3%) and poor in 1 (3%). In control group, 4 (13.3%) were moderate, 2 (6.6%) strong and remaining 24 (80%) excellent. Conclusion: A new easy to use CT based scoring system for CF sinus disease was validated with acceptable inter- and intra-rater reliability.