Objectives: 1) Develop an objective method for quantifying radiologic bone erosion in allergic fungal rhinosinusitis (AFRS); and 2) assess the utility of the new CT scan staging system in differentiating AFRS patient groups. Methods: Patients from two tertiary care rhinology practices with AFRS and available CT scans (1999-2007) were included for review by trained graders. The following novel assessment scale was used: Each paranasal sinus wall with expansion/erosion was scored 1 point, with maximum 3 points possible for each frontal sinus, 2 points for each ethmoid complex, 3 points for each sphenoid sinus, 3 points for each maxillary sinus, and 1 point each for the frontal and sphenoid intersinus septae, yielding maximum of 24 possible points. Results: A total of 111 CT scans were reviewed. Mean score was 7.8 (range, 0-24). Males scored significantly higher than females (mean, 9.3 vs 5.6, P = 0.001). African Americans scored significantly higher than Caucasians (mean, 9.6 vs 5.0, P < 0.001). Conclusions: A scoring system for bone remodeling in AFRS is presented. Males and African-Americans with AFRS demonstrate significantly more bone erosion. Additional analysis of disease course will assess the utility of this staging system in predicting outcomes.