BACKGROUND: Reopening of an occluded internal carotid artery (ICA) is often seen in dissections but only rarely occurs in atherothrombotic occlusion of the internal carotid artery. CASE DESCRIPTION: A 60-year-old man suffered a minor stroke with dysphasia in March 1995. Color-coded duplex ultrasonography of his neck arteries revealed a left ICA occlusion. He was placed on a regimen of aspirin and followed up clinically and with ultrasonography. At follow-up 18 months later, the patient was asymptomatic. On duplex ultrasonography his left occluded ICA was found to be reopened, with a residual, proximal, high-grade stenosis. However, intra-arterial digital subtraction angiography demonstrated a persistent ICA occlusion and a vas vasorum originating from the carotid bulb and draining into the ICA distal to the occlusion. CONCLUSIONS: The rare collateralization of an occluded ICA by vasa vasorum seems to take several months. It can be a pitfall in the ultrasound diagnosis of carotid artery occlusive disease.
BACKGROUND: Reopening of an occluded internal carotid artery (ICA) is often seen in dissections but only rarely occurs in atherothrombotic occlusion of the internal carotid artery. CASE DESCRIPTION: A 60-year-old man suffered a minor stroke with dysphasia in March 1995. Color-coded duplex ultrasonography of his neck arteries revealed a left ICA occlusion. He was placed on a regimen of aspirin and followed up clinically and with ultrasonography. At follow-up 18 months later, the patient was asymptomatic. On duplex ultrasonography his left occluded ICA was found to be reopened, with a residual, proximal, high-grade stenosis. However, intra-arterial digital subtraction angiography demonstrated a persistent ICA occlusion and a vas vasorum originating from the carotid bulb and draining into the ICA distal to the occlusion. CONCLUSIONS: The rare collateralization of an occluded ICA by vasa vasorum seems to take several months. It can be a pitfall in the ultrasound diagnosis of carotid artery occlusive disease.