Characterization of the normal pulmonary surface and pneumonectomy space by reflected ultrasound

Abstract

Interest has been increasing in the use of transthoracic ultrasound for the study of the pleuropulmonary disease. US imaging depends mainly on the physical interactions between ultrasound waves and the tissues being examined. In the thoracic region, the prescence of the chest wall and the air-containing pulmonary tissues cause various artifacts that strongly influence the resulting images. At the interface between tissues and air, the ultrasound beam is totally reflected and produces simple reverberation, comet-tail artifacts, and ring-down artifacts.We report the findings of transthoracic ultrasound in normal healthy subjects and in those who had undergone pneumonectomy.This experience shows that, in terms of the ultrasound artifacts mentioned above, the postpneumonectomy cavity is not significantly different from the healthy lung.

Keywords: Normal pleuropulmonary; Pneumonectomy space; Transthoracic; Ultrasound artifacts.

Fig. 1

Transthoracic ultrasound scan in healthy subjects (supine position). a) Subcostal scan shows “comet-tail” artifacts (arrows) beyond the diaphragmatic line. b) Parasternal scan in a different subject shows “ring-down” artifacts (arrows).

Fig. 2

Laterobasal US scan in a pneumonectomy patient (examined in the seated position) reveal “ring-down” (white arrow) and reverberation artifacts (yellow arrows).

Fig. 3

Computed tomography of the chest in a pneumonectomy patient reveals pleural effusion in the residual space with mediastinal sliding. The intact lung is shifted toward the residual cavity.

Fig. 4

Posterior US scan in a healthy subject shows simple reverberation (white arrow) and ring-down artifacts (yellow arrow).

Fig. 5

Posterior US scan in a pneumonectomy patient reveals a hyperechoic pleural line (arrow) and one “ring-down”.