Snowman (Figure-8) Sign

An ‘increasing interest in abnormal venous return’ seems to have prompted H.A. Snellen and F.H. Albers’ (University Hospital, Leiden) to report their experience with five cases in 1952. Four of their five cases had ‘total abnormal pulmonary venous drainage (via ‘left vena cava’ and left innominate vein into the superior vena cava on the right side)’ with a characteristic roentgenographic configuration that they termed the figure-8 (Figure 1). In the discussion of their second case they said, ‘On both sides of the upper mediastinum a large rounded shadow was seen to bulge into the lung fields; the right shadow was more prominent than the left … With the heart shadow they formed a figure-8 shaped mass.’ ¹ Their diagnoses were confirmed with angiocardiography that showed the top of the figure-8 to be composed of the draining veins with the bottom portion formed by the heart. They noted that many earlier articles had discussed similar cases but emphasized that the conventional chest roentgenogram could make the diagnosis with near complete certainty. The figure-8 sign is often referred to now as the snowman sign (Figure 2). Figure 1 Anteroposterior view of chest with ‘saccular bulging of both sides of the upper mediastinum.’ Reprinted from Snellen and Albers’. The clinical diagnosis of anomalous pulmonary venous drainage. Circulotion, 1952. 6, 801–816. with permission of the American Heart Association https://s3-euw1-ap-pe-df-pch-content-public-p.s3.eu-west-1.amazonaws.com/9781003076568/34c29fd5-5662-4e8f-b58c-badd7fa5d724/content/fig82_1_B.jpg"/> Figure 2 A snowman https://s3-euw1-ap-pe-df-pch-content-public-p.s3.eu-west-1.amazonaws.com/9781003076568/34c29fd5-5662-4e8f-b58c-badd7fa5d724/content/fig82_2_B.jpg"/>