These findings suggest that HRCT of the chest is most useful in the identification of early lung abnormalities in patients with CF with mild respiratory symptoms, whereas for established disease, CCR is still the first-line imaging technique. The advantage of detecting early changes on CT imaging awaits additional confirmation, at least until early therapeutic interventions affecting significantly the final outcome of the disease are demonstrated. In patients with advanced disease, HRCT may be useful in the evaluation of specific lung changes when more aggressive treatment such as chest surgical interventions is indicated. Given the cost of the procedure and the high radiation dosage compared with CCR, a careful assessment of the cost:benefit ratios of HRCT is strongly recommended in CF.