Pulmonary infarction: sonographic appearance with pathologic correlation

Peripheral pulmonary lesions are detectable by ultrasound, the aim of this study was to compare sonograms of pulmonary infarctions with their pathological reports.

A total of 26 lung infarcts in 15 non-fixed autopsy lungs of patients showing necroscopically pulmonary embolism were examined sonographically in a water-bath no later than 5 h after autopsy with a 5- or 7.5-MHz sector scanner. Five of these patients were suspected of pulmonary embolism and underwent sonographic examinations shortly before their death.

Ultrasound showed mainly wedge-shaped (n = 18), hypoechoic areas. Their location, form and size corresponded exactly with pathological findings. Fresh infarcts were homogeneous and more hypoechoic. Older infarcts were well demarcated and showed a hyperechoic reflex in the center corresponding to the bronchiole; this was a sign of segmental involvement. In two cases it was possible to differentiate thromboembolically congested afferent blood vessel directed to the hilus. Ultrasound images from five living patients were similar to the image of the autopsy lung.

In accordance with clinical studies these observations suggest that transthoracic sonography can be an efficient technique in the detection of pulmonary infarction, as well in an early reperfusionable stage as in distinguished infarct formation.