Figure 1b. Pulmonary sequestration in a 6-year-old boy with recurrent episodes of right lower lobe pneumonia. (a) Axial CT angiogram obtained at the level of the lung bases shows a consolidation with large vessels centrally (arrows) in the right lower lobe. (b) Axial CT angiogram obtained inferior to a shows that the vessels originate from a large artery (arrow) that crosses inferior to the diaphragm. (c, d) SSD (c) and magnified volume-rendered (d) reformatted images clearly demonstrate a systemic aberrant artery (arrow) that originates from the celiac trunk (arrowhead in d) and supplies the right lower lung. In c, the trachea and lungs are highlighted in blue and the ribs and lungs are partially transparent. AO = aorta. Surgery revealed an intralobar sequestration.