Torabi, Radmehr

BACKGROUND Rotational vertebral artery occlusion, or bow hunter’s syndrome (BHS), is a rare but clinically important cause of vertebrobasilar insufficiency. Extrinsic compression of the artery is usually caused by osteophytes, fibrous bands, or lateral disc herniation and typically occurs in the setting of anatomical variations, leading to dynamic compromise of the posterior circulation. Neoplastic causes of BHS are rare. OBSERVATIONS The authors present the case of a 72-year-old man with a left vertebral artery–dominant posterior circulation and isolated small right vertebral artery terminating in the posterior inferior cerebellar artery (PICA). He developed progressively worsening dynamic insufficiency of his right PICA circulation due to compression of the right vertebral artery at C2 from an intradural-extradural dumbbell-shaped lesion. This patient was successfully treated via surgical debulking of the lesion and cervical spine fixation and experienced no neurological deficits postoperatively. LESSONS This neoplastic change represents an exceedingly rare presentation for BHS, which warrants further study on its etiology and treatment. https://thejns.org/doi/10.3171/CASE24415