THE X-RAY EXAMINATION OF THE CHEST DURING INSPIRATION IN THE NEWBORN AND DURING INFANCY.

Abstract

Respiratory disease in early infancy attracts increasing interest (Strang, 1963; Karlberg, 1960; Warley and Gairdner, 1962) and radiological examination is being more frequently applied. However, the radiographs present great difficulty in interpretation and the technical difficulties in producing them are by no means confined to the inevitable lack of co-operation. The anatomical features distinctive of the thoracic viscera in infancy are generally recognised, but less attention has been paid to the different formation of the thorax at birth from that of adult life, and the consequent alteration in the mechanism of normal respiration. In the average adult thorax, the angle of the ribs to the thoracic spine is approximately 45 deg. at the level of the 6th rib in the mild-axillary line. In the foetus the ribs are “horizontal”, this term being used by convention when they are at right angles to that part of the thoracic vertebral column with which they are articulated. This foetal formation persists unchanged for the first weeks of post-natal life, after which, at a very variable rate, the adult shape is assumed. Lateral radiographs of the thorax demonstrate the angulation of the ribs relative to the thoracic vertebral column with an accuracy unobtainable in antero-posterior views because of the practical difficulty of avoiding some degree of lordotic or kyphotic distortion (Figs. 1 and 2).