Systemic-to-pulmonary vascular malformation of lung visualized by computer-assisted 3-D reconstruction

While a growing number of cases with pulmonary arteriovenous malformation (PAVM) have been reported, detailed analysis has yet to be found on the relation of abnormal vessels with the whole lung vasculature and airways. To gain more insight into the structure-function interrelation of this disease, we attempted to visualize the vessels in and around the arteriovenous malformation, resorting to computer-aided 3-D reconstruction.

The material was the upper lobe of the right lung from a 44-year-old man resected for recurrent haemoptysis. On pre-surgical selective angiography, an arteriovenous communication was suggested to exist between a tributary of the right 3rd intercostal artery and pulmonary vein. Semi-serial sections were prepared from the material and submitted to 3-D reconstruction of blood vessels and airways. In 3-D images, branches of the 3rd intercostal artery proved to be forming a plexus of abnormally dilated, thin-walled vessels in the subepithelial layer of a membranous bronchiole, a situation clearly explaining the mechanism of haemoptysis. There was no capillary bed interventing between the afferent arteries and draining vessels leading to the pulmonary vein.

This presents the first overall visualization of PAVM, allowing comparison of 2-D microscopy with the corresponding 3-D morphology.