Parietal pleural plaques: a comparison between autopsy and X-ray findings.

In a series of 402 consecutive autopsies, parietal pleural plaques (PP) were found in 68 individuals above 40 years of age. The frequency of PP was 26.9% in males and 3.1% in females. In 28 cases chest roentgenographs taken shortly before death were available. These films were randomly mixed with chest roentgenographs from 33 subjects who had subsequently died and in whom no PP had been found at autopsy. All films were scrutinized by two experienced readers, ignorant of the case histories and autopsy findings. In less than half the PP cases was this diagnosis suggested from the roentgenological examination. On the other hand, the readers had 13 and 14 cases with positive or uncertain findings in the 33 cases with no PP found at autopsy. There was no correlation between plaque area and plaque thickness (r = 0.037). Plaque thickness influenced the accuracy of roentgenological diagnosis significantly. In this series no oblique views were obtained and the X-rays were of mixed quality.