Fig. 4
From: Looking beyond the thrombus: essentials of pulmonary artery imaging on CT
Contrast-enhanced axial CT image (a) and a volume rendered image (b) in a patient with patent ductus arteriosus (PDA) depicting the persistent communication between the pulmonary artery and descending aorta (arrow). The flow direction in the post-natal period is aorta to pulmonary artery as the pulmonary pressures decrease. This can lead to pulmonary hypertension, which on CT will present as enlarged pulmonary trunk as seen on the volume rendered image