Atelectatic Bronchiectasis in Childhood

The occasional occurrence in radiograms of the chest of triangular shadows, situated behind the heart-shadow on the left or across the cardio- phrenic angle on the right, has attracted the attention of radiologists for many years. It is, however, only since the introduction of lipiodol for diagnostic purposes that the frequent association of these shadows with bronchiectasis has been recognized. Many of the earlier writers on the subject regarded the triangular shadow as being diagnostic of a mediastinal effusion, as described by Dieulafoy', but almost consistently negative results on needling and the absence of fluid when open operation was adopted (Sergent and Bordet2) led to the realization that effusion could only rarely be held responsible. Rist, Jacob, Troeme, and Soulas3' 4 recognized the presence of bronchiectasis in a number of classical cases which they described, and considered that the shadow was due to the formation of a secondary ' adhesive mediastinal pleurisy ' over the bronchiectatic area, associated with pneumonic infiltration within it. A similar interpretation has been accepted by the majority of French clinicians who have described cases. In England and America the triangular shadow is generally regarded as being due to collapse of the lower lobe, or of an accessory lobe, of the lung, though this view does not of course exclude the possibility of pneumonic consolidation or fibrosis within it, nor of thickening of the pleura with which it is covered.