A Case of Intrathoracic Carotid Bifurcation Without Klippel-Feil Syndrome

Intrathoracic carotid bifurcation is a rare vascular anomaly, with only 8 cases reported. This vascular anomaly was recently correlated with Klippel-Feil syndrome, a rare congenital disorder involving fusion of the cervical vertebrae.

A 70-year-old deaf mute man was admitted to our department because of right hemiparesis and right sensory disturbance. He displayed no abnormalities associated with Klippel-Feil syndrome. Diffusion-weighted imaging revealed acute multiple infarcts in bilateral hemispheres. Computed tomography angiography showed that the left common carotid artery bifurcated at the T2 vertebral level. No significant stenosis was seen in the carotid arteries. Transesophageal echocardiography confirmed a complicated atheromatous lesion at the aortic arch.

This case was diagnosed with aortogenic brain embolism, incidentally accompanied by left intrathoracic carotid bifurcation without Klippel-Feil syndrome.

Intrathoracic carotid bifurcation can occur in cases without Klippel-Feil syndrome. The knowledge of this anatomic variation is important in evaluating vascular lesions of the carotid arteries in patients with stroke.