Radiation-induced bilateral common carotid artery occlusion

A 71-year-old female with a history of 10-year postoperative radiation therapy for laryngeal carcinoma was admitted to our hospital due to acute dysarthria and weakness in her left extremities. Brain diffusion-weighted imaging (DWI) revealed multiple hyperintense foci in the right hemisphere, suggestive of watershed cerebral infarction. There were no significant findings in the intracranial arteries except for severe local stenosis at the left V4 segment on head computed tomography angiography (CTA) (A). Neck CTA demonstrated complete occlusion of the origin of bilateral common carotid artery (CCA) and left vertebral artery (VA), but bilateral internal carotid arteries (ICA), left external carotid artery (ECA), and intracranial segment of VA were visualized through abundant collaterals formed by the branches of thyrocervical and costocervical trunk and vertebrocarotid muscular branches that anastomosed with the bilateral CCA terminals and left V3 segment (B/cover). Moreover, the bilateral subclavian artery showed mild to moderate stenosis and the right ECA depicted occlusion, whereas the right VA was patent. Cross-sectional CTA images confirmed occlusion of three extracranial arteries (C, D). Given the high risk of revascularization, medical therapy was recommended. Nine days after dual antithrombotic therapy and butylphthalide combined with edaravone, the patient was discharged with mild improvement in her muscle weakness. The patient's consent was obtained to publish the case. Radiotherapy, a common treatment modality for head and neck cancer, may result in carotid artery stenosis or occlusion as a late life-threatening complication.1Zheng Z.Z. Zhao Qin Wei J.L. et al.Medical prevention and treatment of radiation-induced carotid injury.Biomed Pharmacother. 2020; 131110664Crossref Scopus (9) Google Scholar Bilateral common carotid artery occlusion (BCCAO) is a rare condition with an incidence of less than 1% in all stroke patients, which has been associated with hypertension, diabetes mellitus, smoking, dyslipidemia, and vasculitis.2Lai S.L. Chen Y.C. Weng H.H. et al.Bilateral common carotid artery occlusion-a case report and literature review.J Neurol Sci. 2005; 238: 101-104Abstract Full Text Full Text PDF Scopus (23) Google Scholar,3Wan Y. Chen H.C. Lee C.Y. et al.Acute visual loss as the first ocular symptom in a Sjögren's syndrome patient with bilateral common carotid artery occlusion: a case report.BMC Ophthalmology. 2021; 21: 409Crossref Scopus (0) Google Scholar Vertebrocarotid collaterals due to BCCAO may provide blood keeping the internal carotid arteries patent distal to the occlusion.4Oguzkurt L. Kizilkilic O. Tercan F. et al.Vertebrocarotid collateral in extracranial carotid artery occlusions: digital subtraction angiography findings.Eur J Radiol. 2005; 53: 168-174Abstract Full Text Full Text PDF PubMed Scopus (0) Google Scholar This case highlights the rarity of BCCAO induced by radiotherapy, presenting with a minor stroke. None.