Bow Hunter's Syndrome: Illustrative Teaching Case with Insights and Lessons

Abstract

A 63-year-old woman with a history of left basal ganglia and paraventricular infarcts, type II diabetes, and hypertension presented with recurrent dizziness when turning her head to the right. These episodes, lasting for eight months, were often accompanied by nausea and vision disturbances but resolved spontaneously. Dynamic digital subtraction angiography (DSA) revealed significant blood flow slowdown in the left vertebral artery (VA) with a 90° right neck turn, showing narrowing in the V3 segment of the left VA. The patient was diagnosed with Bow Hunter's Syndrome (BHS) and underwent atlantoaxial fusion surgery. On day three post-surgery, she developed sudden weakness in the left upper limb, visual field hemianopia, impaired sensation, and slurred speech. Emergency CT and MRI revealed acute infarcts in the basal ganglia and periventricular area. Following antiplatelet therapy and volume expansion, her symptoms improved, and by day seven, her speech and left upper limb strength had partially recovered, though residual symptoms persisted at discharge. One year post-surgery, the dizziness had resolved, but residual symptoms from the infarction remained. Cervical fusion effectively treated the symptoms of BHS; however, surgery should be considered with caution in patients with thromboembolic risk factors.