An incomplete vascular ring causing respiratory distress.

Kommerell's diverticulum is a rare saccular aneurysmal dilation of the descending aorta. We report a case of a 3.5-year-old boy with the extremely rare combination of Kommerell's diverticulum with a right descending aorta and proximal patent ductus arteriosus aneurysm forming an incomplete vascular ring. To our knowledge, this rare case has not been reported to date.