Many score methods have been created to measure paranasal sinus abnormalities seen under CT scan. Currently, the Lund-Mackay staging system is widely accepted. However, its results may be affected by the development in children. AIM: To assess the precision and accuracy of a new tomography score, called "opacification-development ratio". It translates the percentage of sinus area that is opaque. MATERIALS AND METHODS: A cross-sectional study was prospectively conducted in patients ranging from 0-18 years of age who underwent CT scan assessment of rhinosinusitis. Two independent radiologists examined each scan twice, using both the Lund system and the ratio herein proposed. RESULTS: The opacification-development ratio reached substantial intra and inter-examiner agreement, similar to the Lund system (Kappa > 0.60). Considering the Lund system as the gold standard, the most accurate cut-off point was approximately 15 (sensitivity and specificity approach 90%). There was a strong linear correlation between the two methods (r > 90). CONCLUSIONS: opacification-development ratio is precise and correlates with the Lund system. A cut-off point set at 15 could be used to call a test positive.
pediatrics; radiology; sinusitis; tomography
