Effect of kilovoltage on detectability of pulmonary nodules in a chest phantom

A partial chest phantom was constructed to examine the effect of kilovoltage on the detectability of pulmonary nodules. Four different energies were studied: 100, 150, 200, and 300 kVp. Nodule detectability improved with increasing energies up to 200 kVp, but improvement was relatively small and was accompanied by an almost equal rise in the number of false positive readings. Patient exposures were least at 200 kVp. There seems to be no advantage in a 300 kVp technique, since nodule detectability decreased and patient exposures increased at this energy.