en Radiation Biology Radiation Biology تحقيق بديع Original Research <div style="text-align: justify;"><span style="font-size:10pt"><span style="text-justify:newspaper"><span style="text-kashida-space:50%"><span style="line-height:119%"><span style="font-family:Calibri"><span style="color:black"><span lang="en-US" style="font-size:9.0pt"><span style="font-family:Calibri"><span style="color:#1f497d"><span style="font-style:italic"><span style="font-weight:bold"><span style="language:en-US">Background:</span></span></span></span></span></span> <span lang="en-US" style="font-size:9.0pt"><span style="font-family:Calibri"><span style="language:en-US">This study investigated the relationship between extracranial internal carotid artery (EICA) and extracranial carotid artery (ECA) tortuosity and clinical prognosis in acute anterior circulation ischemic stroke (AIS). </span></span></span><span lang="en-US" style="font-size:9.0pt"><span style="font-family:Calibri"><span style="color:#1f497d"><span style="font-style:italic"><span style="font-weight:bold"><span style="language:en-US">Materials and Methods: </span></span></span></span></span></span><span lang="en-US" style="font-size:9.0pt"><span style="font-family:Calibri"><span style="language:en-US">We retrospectively analyzed 201 patients with anterior circulation AIS who underwent head and neck CT angiography (CTA) between January&ndash;December 2023.CTA was performed using a Discovery CT750 HD scanner (GE Medical Systems), with scanning extending from the aortic arch to the skull vertex. Iopromide contrast agent (37g iodine/100ml) was administered intravenously. Images were reconstructed at 0.63-mm slice thickness using multiplanar reformation (MPR) and 3D volume rendering (VR). </span></span></span><span lang="en-US" style="font-size:9.0pt"><span style="font-family:Calibri"><span style="color:#1f497d"><span style="font-style:italic"><span style="font-weight:bold"><span style="language:en-US">Results: </span></span></span></span></span></span><span lang="en-US" style="font-size:9.0pt"><span style="font-family:Calibri"><span style="language:en-US">Tortuosity Index (TI) of EICA and ECA were independent predictors of poor 90-day prognosis (modified Rankin Scale [mRS] &ge;3) in multivariate regression (Model I: EICA OR=1.038, P=0.007.ECA OR=1.052, P=0.015). ROC analysis showed ECA-TI&ge;12.5 predicted poor prognosis with higher specificity (AUC=0.623,sensitivity 55.6%,specificity 68.3%) than EICA-TI &ge;14.5 (AUC=0.601,sensitivity 61.9%,specificity60.7%). </span></span></span><span lang="en-US" style="font-size:9.0pt"><span style="font-family:Calibri"><span style="color:#1f497d"><span style="font-style:italic"><span style="font-weight:bold"><span style="language:en-US">Conclusions: </span></span></span></span></span></span><span lang="en-US" style="font-size:9.0pt"><span style="font-family:Calibri"><span style="language:en-US">Increased EICA/ECA tortuosity independently correlates with poor AIS outcomes, with ECA-TI being a superior prognostic indicator.</span></span></span></span></span></span></span></span></span></div> Carotid arteries, stroke prognosis, intracranial arteriosclerosis, x-ray computed, risk factors. 1057 1063 http://ijrr.com/browse.php?a_code=A-10-1-1435&slc_lang=en&sid=1 Y. Wang 7900319475328460032582 7900319475328460032582 No Department of Neurology, Jingxian Hospital, Xuancheng, Anhui 242500, China W. Cui ssamsca2001@163.com 7900319475328460032583 7900319475328460032583 Yes Department of Neurology, Shahe Hospital Changping District, Beijing 102206, China