Abstract Number: Esoc2026a1079 When Surgery Causes Chronic Cerebral Hypoperfusion: Iatrogenic Common Carotid Artery Occlusion

Background and aims While atherosclerosis and embolic mechanisms account for the majority of supra-aortic arterial occlusions, traumatic and iatrogenic injuries constitute a rare aetiology. When present, they may lead to chronic cerebral hypoperfusion and delayed ischaemic damage. We present a representative case. Methods Case report. Results 73-year-old woman with surgical history of total thyroidectomy and parathyroidectomy for adenocarcinoma, resulting in iatrogenic intraoperative occlusion of the right CCA with secondary ischaemic injury in the angular region of the right MCA territory. As sequelae, she developed orthostatic baroreflex dysfunction. During neurosonological follow-up, she showed occlusion at the origin of the right CCA with ICA perfusion via retrograde flow from branches of the ECA. ICA flow was hypokinetic (peak systolic velocity < 20 cm/s and pulsatility index 0.4). Brain Tc99m-HMPAO SPECT demonstrated a centroparietal region of hypoperfusion. The patient was subsequently admitted to perform a right subclavian–carotid bypass with prosthetic graft and side-to-side anastomosis, achieving vascular patency with adequate arterial flow. Follow-up brain MRI showed increased T2 and FLAIR signal in the cortex of the right superior temporal gyrus without diffusion restriction, consistent with chronic ischaemic injury. Conclusions This review emphasises that, despite traumatic aetiologies of arterial occlusion are uncommon, they should be considered. In particular, inadvertent ligation of the CCA during surgical procedures is a severe and extremely rare complication associated with a high risk of neurological sequelae, which depends on the ability of collateral circulation to compensate for the affected territory, with up to 40% of patients developing severe sequelae according to the literature. Conflict of interest All authors: nothing to disclose. Figure 1 - belongs to Results Figure 1 - belongs to Conclusions