[Table/Fig-17a]:

Truncus arteriosus. A three-month-old male with breathing difficulty, recurrent chest infection, diagnosed with truncus arteriosus: (a) Diagrammatic representation of vascular anatomy in truncus arteriosus; (b) Plain radiograph shows moderate cardiac enlargement with increased pulmonary arterial markings, especially on right side(open arrow); (c) echocardiography shows a single trunk(open arrow) providing origin to pulmonary artery and aorta; (d-f) Reconstructed outflow CT images shows a single large ascending aorta overriding large septal defect(circle); (e) Reconstructed axial oblique CT view shows pulmonary arteries arising from posterior aspect of aorta (triangle).