Variabilidad de la medida del mediastino (Pedículo vascular e Índice cardiotorácico) en la radiografía de tórax con la posición y respiración

Objective: to quantify the measurements of the mediastinum, cardiothoracic index and vascular pedicle in the radiographs taken with the patient in the supine position and in expiration, compared with those taken in vertical and in inspiration, and thus propose a standardization of the mediastinal evaluation process.Materials and methods: a prospective inter-observer correlation study, carried out in the diagnostic imaging service of the Hospital de San Jose, in the period between January and December of 2003. The patients selected within the inclusion criteria underwent four radiographs in vertical and decubitus, in inspiration and expiration, and the IC and PV were determined, measurements made independently by two expert radiologists. The degree of correlation between the two observers was evaluated using the Pearson coefficient (p 0.05).Conclusion: the variability in men with the change of position to decubitus in expiration is 0.06 for the IC and 1.35 cm for the PV. In women, the variability is 0.09 for the IC and 1.18 cm for the PV independent of age. It was found that the findings correlate with the scarce publications, but the data obtained in our population sample are lower than those reported in the international literature.Abbreviations: MM, mediastinal measurements; IC, cardiothoracic index; PV, vascular pedicle; DS, standard deviation; VI, vertical inspiration; VE, vertical expiration; DI, decubitus inspiration; DE, decubitus expiration.