View larger version (267K)

Figure 17b. Spiral CT angiography (5-mm collimation, pitch of 1.7, 30% iodinated contrast agent) performed in a 61-year-old patient evaluated for left hilar enlargement. (a-d) Spiral CT angiograms enable recognition of the abnormal juxtahilar route of a left upper lobe pulmonary vein (•) draining into the left inferior pulmonary vein ( in d). (e) Three-dimensional SSD (lateral view, threshold of +150 HU) generated from the same data set provides an overall view of the sub- and retro-hilar route of the abnormal vein (•) and of its normal drainage into the left atrium ().