Editorial

I n reference to the article of Ganei and his colleagues in this issue of Arch Iran Med, about the correlation of HRCT with cardiopulmonary exercise in mustard gas victims who had near normal spirometry results, the following points are important: Firstly, after development of pulmonary physiology and chest radiology, numerous works have been undertaken regarding the clinico-pathologico-radiologic correlations; however, the results were inconclusive and non-linear, particularly in cases of mild lung involvement. This is perhaps due to the large reserve capacity of the lungs and good compensation for disease process with auto- regulation mechanisms. Although HRCT gives more information about lung parenchyma and small airways, and we have good literature regarding HRCT and lung disease including small airway disease, the major drawbacks of HRCT are radiation exposure and impact on the outcome of most patients if we consider other less damaging diagnostic modalities. The cost and availability of HRCT are other points that may be important in developing countries, which have resource limitations.