Case 335.

History: An 84-year-old female patient presented for routine CT angiography (CTA) of the arteries of the neck following right carotid endarterectomy for 75% stenosis, which had been performed without incident 2 months prior. The patient had also been diagnosed with 72% stenosis of the left carotid artery, although it was asymptomatic and thus endarterectomy was not required. The medical history included arterial hypertension and an incomplete left bundle branch block. CTA was performed according to standard procedure, with the region of interest to initiate the examination being placed within the aortic arch and contrast material injected at 5 mL/sec via a catheter placed in the left antecubital fossa. The catheter was successfully tested, and the contrast material was subsequently injected without incident, with the patient reporting no pain and the automatic pressure sensor showing no anomalies. The scan was automatically launched because the attenuation within the aortic arch reached 800 HU (Figs 1-3).