Anomalous vertebral arteries in Klippel-Feil syndrome with occipitalized atlas: CT angiography.

Klippel-Feil syndrome is an uncommon anomaly that may be asymptomatic. Early clinical signs such as restricted neck motion or short neck can be subtle and incorrectly treated as spasms. High incidence of associated craniovertebral junction (CVJ) anomalies such as occipitalized atlas predisposes them to serious neurologic complications requiring invasive procedures and surgeries. However, these often have anomalous vertebral artery course which is more prone to injury during CVJ procedures, and also sparsely known in radiology literature. We demonstrate the importance of computed tomography angiography in preprocedural planning to avoid catastrophic injury to anomalous vertebral artery at CVJ in such case.