Ultrasonographic Detection of Extracranial Vertebral Artery Compression in Bow Hunter’s Brain Ischemia Caused by Neck Rotation

303 partum cerebral venous thrombosis [1–3, 7]. Although the puerperal state is considered to be a risk factor in and of itself [3, 7] hematological abnormalities, such as the antiphospholipid syndrome, deficiencies of antithrombin III and proteins S and C and factor V Leiden mutations, are occasionally encountered [5, 6, 8] and need to be ruled out, as was done in our patient. Much more uncommon are dissections of the cervico-cephalic arteries in the postpartum period following uncomplicated deliveries, with only 12 cases reported so far [1–5, 7, 8]. Although our patient initially had a neck ache on the side of her carotid dissection, it subsequently decreased and pain on the side of her jugular thrombosis remained her dominant complaint. In fact, the presence of a small cerebellar infarct led to the diagnosis of multiple cervical arterial dissections. The ‘string-of-beads’ pattern angiographically noted in both carotid arteries (fig. 3a, b) in our patient was consistent with medial fibroplasia, the most common pathological pattern in fibromuscular dysplasia [10]. The many dissections encountered in the vertebral arteries, although less typical, were also highly suggestive: pseudo-aneurysms of the right vertebral (fig. 4) and carotid (fig. 3a) arteries are the hallmark of medial dissections, and the tubular narrowing of the proximal left vertebral artery (fig. 5) and both distal vertebral arteries is consistent with medial hyperplasia, the second most common pathological finding in fibromuscular dysplasia [9]. The patient received long-term warfarin, which is the recommended standard therapy both for arterial dissections of the cervicocephalic arteries and for cerebral venous thrombosis. In conclusion, although arterial emboli and cerebral venous thrombosis are the most common causes of stroke in the puerperium [1–3, 5, 7, 8], the presence of cervicalgia or an unexplained acute infarct on MRI should alert physicians to the possibility of cervico-cephalic arterial dissection.