FIG 1. A, DSA, right CCA injection, unsubtracted AP view. Carotid bifurcation projects over posterior arch of right fourth rib (star). Note medial position of right ICA distal to bifurcation (arrow) and severe degenerative changes at C7–T1.

B, DSA, right CCA injection, unsubtracted lateral view. Because of its intrathoracic location, the carotid bifurcation could not be properly imaged on a lateral view. Standard lateral neck view shows unusual length of ICA and ECA. ICA is kinked at C2–C3. Note fusion of the C2 and C3 vertebral bodies.

C, DSA, left CCA injection, unsubtracted AP view. Left carotid bifurcation projects over posterior arch of the second rib (star). Here also, note medial position of ICA distal to the bifurcation (arrow).

D, DSA, right VA, unsubtracted AP view. See impingement of right VA at C7–T1 level due to severe degenerative changes secondary to the Klippel-Feil anomaly, with lumen narrowing of approximately 50% (arrow).

E, DSA, left subclavian artery, AP subtracted view. VA is also narrowed by C7–T1 degenerative changes, with a lumen narrowing of approximately 70% (arrow).