High resolution computed tomography of the chest in cystic fibrosis (CF): is simplification of scoring systems feasible?

The purpose of this study was to simplify HRCT scoring systems (SS) for CF by selecting representative HRCT parameters. Forty-two consecutive patients with CF underwent baseline and follow-up chest HRCT. Three radiologists evaluated 84 HRCTs employing five SS. "Simplified" HRCT SS were formed by selection of parameters exhibiting statistically significant relations with FEV1. Pulmonary function tests (PFTs) and nutrition (IBW%) were recorded. Regression analysis, Pearson correlation and T-test were used for statistical analysis. Three HRCT parameters were selected for the formation of "simplified" HRCT SS (severity of bronchiectasis, bronchial wall thickening, atelectasis-consolidation) using regression analysis. There was excellent correlation between each "simplified" and corresponding complete score (0.892 < r < 0.0967, p < 0.0001) or the remaining four complete scores (0.786 < r < 0.961, p < 0.0001). Strong correlation was found among the five "simplified" scores (0.803 < r < 0.997, p < 0.0001). Comparing baseline complete and "simplified" scores with corresponding follow-up ones, significant worsening was observed (p < 0.0001). PFTs and IBW% did not change significantly. HRCT scores correlated moderately with FVC and FEV1, but there was no correlation with FEF25-75 and IBW%. "Simplified" HRCT SS are as reliable as the complete ones and detect progression of lung disease earlier than clinical parameters. They are easy to use and could be adopted in clinical practice.