Images are from Freedom's CHD Textbook of Angiography Vol. II (1997) p.948.
Based on Edwards Hypothetical Double Arch.
Numbers in lower diagram indicate possible sites of regression. Vascular anomalies occur according to the site of regression.
Normal left arch - 1, 7 regress.
Right arch with mirror-image branching - 2,8 regress.
Left arch with aberrant RSCA - 1, 3 regress.
Right arch with aberrant LSCA - 2,6 regresss.
Figure out other vascular anomalies...similarly:
Double arch - both arches patent
Double arch with atresia of a segement of left arch
Double arch with atresia of a segement of right arch
Left arch with right descending aorta
Left arch with isolation of RSCA
Right arch with left ductus (retroesophageal)
Right arch with isolation of LSCA
Right arch with aberrant left innominate artery
Right arch with isolation of left innominate artery