Absence of the Left Common Carotid Artery with Internal and External Carotid Arteries Lacking Separate Origins: A Rare Case Report and Review of the Literature

Absence of the Left Common Carotid Artery with Internal and External Carotid Arteries Lacking Separate Origins: A Rare Case Report and Review of the Literature | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Case Report Absence of the Left Common Carotid Artery with Internal and External Carotid Arteries Lacking Separate Origins: A Rare Case Report and Review of the Literature Jinguang Zhou, Yongfeng Zhao, Yunxia huang, Ping Zhou This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-9263858/v1 This work is licensed under a CC BY 4.0 License Status: Under Revision Version 1 posted 14 You are reading this latest preprint version Abstract Background Absence of the common carotid artery is a rare vascular anomaly. Patients are typically asymptomatic unless accompanied by other vascular abnormalities. This condition is usually associated with independent origins of the internal and external carotid arteries, whereas cases without separate origins are particularly rare, with fewer than ten reported in the literature. Case presentation A 24-year-old man was incidentally found to have absence of the left common carotid artery during imaging evaluation for scoliosis. Ultrasonography and computed tomography angiography demonstrated absence of the left common carotid and brachiocephalic arteries, with the left internal and external carotid arteries lacking separate origins. Extensive collateral circulation was observed via the deep cervical, occipital, and vertebral arteries, accompanied by retrograde flow in the left external carotid and superior thyroid arteries. The patient was asymptomatic and did not require vascular intervention. Conclusions Ultrasonography is the first-line diagnostic modality, while computed tomography angiography with three-dimensional reconstruction provides complementary and comprehensive anatomical assessment. Accurate recognition of such vascular anomalies is crucial, as it can reduce the risk of iatrogenic injury associated with atypical vascular pathways and facilitate evaluation of potential cerebrovascular complications. Clinical trial number Not applicable Absence of the common carotid artery Collateral circulation Computed tomography angiography Ultrasound Embryology. Figures Figure 1 Figure 2 Background Absence of the common carotid artery (ACCA) is an extremely rare vascular anomaly. From its first description in 1784 to 2019, only 87 cases were reported 1 . A recent review expanded the total number of documented cases to 122 2 . ACCA is typically associated with independent origins of the external and internal carotid arteries, whereas cases lacking separate origins are extremely rare, with fewer than ten reported previously 3–9 . This anatomical variation is usually asymptomatic and is most often detected incidentally during autopsy or imaging performed for unrelated clinical conditions, with no apparent sex predilection 10 . Here, we report a rare case involving absence of the left common carotid artery (CCA) and brachiocephalic artery (BA), combined with left internal carotid artery (ICA) and left external carotid artery (ECA) without independent origins. Case presentation A 24-year-old male presented to our hospital for further evaluation of scoliosis. He had no significant past medical history or family history, and his general condition was stable with stable vital signs. Neck ultrasonography ( Fig. 1 ) revealed absence of the left CCA. The left ICA and ECA demonstrated normal course and intact lumens, with multiple collateral vessels observed at the carotid bifurcation. Color Doppler flow imaging showed retrograde flow in the left ECA, with only minimal antegrade flow detectable during late diastole, and a reversed flow waveform in the left superior thyroid artery. Further evaluation with computed tomography angiography ( Fig. 2 ) of the head and neck demonstrated absence of the left CCA and BA. The aortic arch gave rise sequentially to the right CCA, right subclavian artery (RSA), and left subclavian artery (LSA). The bifurcation of the left carotid artery was located at the level of the C4 vertebral body, with abundant collateral vessels observed around the bifurcation. The left deep cervical artery was dilated and formed a tortuous anastomotic network with the occipital arteries and vertebral arteries at the level of the C2 vertebral body. The intracranial arteries demonstrated normal configuration and course, with no evidence of significant stenosis, dilation, aneurysm, or other vascular malformations. Despite the absence of the left CCA and BA, the patient remained asymptomatic and required no specific intervention. However, after discussion, the patient chose to defer surgical correction of scoliosis. A–B: gray-scale ultrasonography in longitudinal and transverse views demonstrating absence of the left common carotid artery, with visualization of a normal carotid bifurcation region, internal jugular vein, and vagus nerve. C–F: Color Doppler imaging showing flow patterns in the internal carotid artery, external carotid artery, and superior thyroid artery. Reversed flow is observed in the external carotid artery and superior thyroid artery, whereas the internal carotid artery demonstrates preserved antegrade low-resistance flow. Abbreviations: VN, vagus nerve; IJV, internal jugular vein; STA, superior thyroid artery. A: Absence of the brachiocephalic artery, with the aortic arch giving rise sequentially from right to left to the RCCA, RSA, and LSA. B: Absence of the LCCA, with the left ICA and ECA lacking separate origins. C: Marked dilation of the left DCA compared with the contralateral side. D: Extensive collateral vessels forming a tortuous anastomotic network around the left carotid bifurcation. Abbreviations: DCA, deep cervical artery. Discussion and conclusion ACCA is an extremely rare anatomical anomaly. The first case was reported by Malacarne in 1784 11 . Up to 2019, only 87 cases had been documented 1 , and a recent review expanded the total number to 122 2 . This anomaly shows no significant lateral or sex predilection 12 . Patients are typically asymptomatic unless associated vascular abnormalities are present. Various vascular abnormalities have been reported to be associated with ACCA, including, but not limited to, cervical aortic arch, double aortic arch, right-sided aortic arch, interrupted aortic arch, intracranial aneurysms, internal carotid artery aneurysms, aberrant right subclavian artery, cerebral venous sinus thrombosis, persistent trigeminal artery, and persistent proatlantal intersegmental artery 4,8,9,13–18 . Wood retrospectively reviewed 17,500 patients over a 15-year period and identified three cases, corresponding to an estimated incidence of approximately 0.017% 19 . Given its typically asymptomatic presentation, ACCA is most often detected incidentally during diagnostic or therapeutic procedures, making its true prevalence difficult to ascertain. In the typical anatomy, the aortic arch gives rise sequentially from right to left to the BA, left CCA, and LSA. This classic three-branch configuration is observed in approximately 87.5% of individuals 20 . ACCA is most commonly accompanied by independent origins of the internal and external carotid arteries. In a review of 87 cases, Vasovic reported that four-branch aortic arches were more frequently observed in patients with left ACCA, with the left ICA and ECA often originating directly from the aortic arch. Conversely, three-branch aortic arches were more common in patients with right ACCA, in which the right ICA and ECA frequently originated directly from the BA. Interestingly, in the present case, both the BA and left CCA were absent, and the left ICA and ECA were present without separate origins. Although the aortic arch gave rise to three branches, it did not conform to the typical three-branch pattern, instead giving rise sequentially to the right CCA, RSA, and LSA. This anomaly may be related to developmental abnormalities of the aortic arch system during the embryonic period. During early embryogenesis, the aortic arches and their branches develop from the ventral and dorsal aortae, together with the six paired pharyngeal aortic arteries situated between them 21 . The dorsal aortic segment between the third and fourth pharyngeal aortic arteries, known as the ductus caroticus. normally regresses by the sixth week of development or when the embryo measures 12–14 mm 22 . The CCA develops from the aortic sac and the proximal segment of the third aortic arch, with the distal portion of the third arch continuing as the proximal ICA 21 . The ECA form by migration of the ventral pharyngeal arteries from the aortic sac to the third arch 23 . The aortic sac is the first portion of the aorta to develop. It later forms a right and a left horn. The right horn forms the BA, while the left horn, together with the stem of the aortic sac, forms part of the aortic arch proximal to the BA 24 . Incomplete development or regression of the right horn may result in absence of the BA, leading to the RSA and right CCA arising directly from the aortic arch 25 . Degeneration of the third aortic arch with persistence of the ductus caroticus 26 , or degeneration of the fourth arch together with persistence of the third arch and ductus caroticus 27 , has been proposed to result in the ICA and ECA arising independently; the latter scenario is often associated with a cervical aortic arch. Another hypothesis suggests that when the origin of the ECA is sufficiently distal from the caudal end of the third arch, the CCA may fail to develop 28 . However, in the present case, ACCA was not attributable to independent origins of the ICA and ECA. Instead, it appears to result from a lack of connection between the aortic and cervical arterial systems. Kwak suggested that this may be due to abnormal regression of the aortic sac or the proximal third aortic arch, which preserves the carotid bifurcation but prevents the formation of a complete CCA 3 . The occipital artery maintains communication between the external carotid artery system and the vertebral artery via the posterior anastomotic radicular branches 29 . The deep cervical artery, originating from the costocervical trunk, serves as a major anastomotic pathway to the vertebral artery at the C2–C4 levels 30 . Additionally, the external carotid artery can form a stable collateral connection with the deep cervical artery through the deep branch of the occipital artery. Consequently, the occipital–deep cervical–vertebral arterial network functions as a compensatory pathway in cases of carotid developmental anomalies or occlusive lesions, enhancing blood flow to maintain posterior circulation and intracranial perfusion. This extensive collateral system likely accounts for the absence of clinical symptoms in the present patient. Color Doppler ultrasonography is the first-line modality for the diagnosis of ACCA, providing clues to CCA absence or carotid bifurcation anomalies 31–33 . The presence of an absent CCA does not significantly affect the spectral Doppler waveform characteristics of the ICA and ECA, which typically demonstrate low-resistance and high-resistance flow patterns, respectively 31 . computed tomography angiography combined with multiplanar and three-dimensional reconstructions allows precise evaluation of the cervical vascular anatomy, variant arterial origins, and intracranial vasculature, offering a more comprehensive imaging assessment 19 . Such vascular variations can lead to hemodynamic alterations, including increased blood flow and changes in flow direction, resulting in additional hemodynamic stress and potentially increasing the risk of cerebrovascular events. Patients with these anomalies are generally considered to have a higher risk of adverse events 1 . In a review of 63 cases of CCA absence, Hopper reported that more than 50% of patients experienced cerebrovascular-related symptoms 34 . For asymptomatic individuals, there is currently no recommendation for intervention or surgical correction of this developmental anomaly. We report a rare case of left ACCA without separate origins of the left ICA and ECA. This anatomical variant is typically asymptomatic. However, accurate recognition of such vascular anomalies is clinically important, as it can guide endovascular procedures involving the aorta and cerebral vessels, reduce the risk of iatrogenic injury due to atypical vascular routes, and assist in assessing the risk of concomitant cerebrovascular diseases. Abbreviations ACCA, absence of the common carotid artery; CCA, common carotid artery; ICA, internal carotid artery; ECA, external carotid artery; BA, brachiocephalic artery; RSA, right subclavian artery; LSA, left subclavian artery. Declarations Ethics approval and consent to participate This study was approved by the Ethics Committee of The Third Xiangya Hospital of Central South University (Approval No. 251088). Written informed consent was obtained from the patient for participation in this study. Consent for publication Written informed consent was obtained from the patient for publication of the clinical data and accompanying images. Availability of data and materials The datasets used and/or analysed during the current study are available from the corresponding author on reasonable request. Competing interests The authors declare no conflict of interest. Funding This work was supported by National Natural Science Foundation of China [81871367]. The funding assisted in the collection of clinical data and publication fees. Authors' contributions J. Zhou performed data analyses and wrote the manuscript. Y. Huang participated in data collection and patient follow-up. Y. Zhao conducted the clinical diagnosis and data collection. P. Zhou critically revised the manuscript. All authors read and approved the final manuscript. Acknowledgements None. References Vasović L, Trandafilović M, Vlajković S. Congenital Aplasia of the Common Carotid Artery: A Comprehensive Review. Biomed Res Int . 2019;2019:9896138. doi:10.1155/2019/9896138 Ramputi L, Mazzaccaro D, Tissir K, et al. Anatomical variations of origin of the internal carotid artery: Report of two cases and systematic review of the literature. Vascular . Oct 2025;33(5):1191-1199. doi:10.1177/17085381241283095 Kwak Y, Choi MK, Kim KH, Cho JH. Rare Case of Absent Common Carotid Artery Likely Associated with Intracranial Aneurysm Development. J Stroke Cerebrovasc Dis . Jun 2019;28(6):e77-e80. doi:10.1016/j.jstrokecerebrovasdis.2019.01.017 Cao YH, Zhang GY, Cheng SQ, Han JL, Zhao G. Proatlantal intersegmental artery with absence of the common carotid artery. Clin Neurol Neurosurg . Apr 2011;113(3):245-6. doi:10.1016/j.clineuro.2010.10.016 Quinones G, Srinivasan A. Absence of the right common carotid artery: a rare case without separate origins of the internal and external carotid arteries. Clin Imaging . May-Jun 2017;43:184-187. doi:10.1016/j.clinimag.2017.03.009 Kobayashi D, Natarajan G, Joshi A, Aggarwal S. Congenital absence of bilateral common carotid arteries. Ann Thorac Surg . Feb 2013;95(2):719. doi:10.1016/j.athoracsur.2012.06.052 Kunishio K, Yamamoto Y, Sunami N, Asari S. Agenesis of the left internal carotid artery, common carotid artery, and main trunk of the external carotid artery associated with multiple cerebral aneurysms. Surg Neurol . Feb 1987;27(2):177-81. doi:10.1016/0090-3019(87)90292-8 Chen L, Liu JM, Zhou D. Congenital absence of the right common carotid artery, internal carotid artery and external carotid artery associated with anterior communicating artery aneurysm: a rare case. Neurol Sci . Dec 2008;29(6):485-7. doi:10.1007/s10072-008-1030-2 Xie T, Zhang XB, Li QP, Zhu W, Zhou H, Gu Y. Hemifacial spasm patient with ipsilateral total absence of common carotid artery, vertebral artery and aneurysm of the contralateral internal carotid artery. Surg Radiol Anat . Aug 2010;32(7):707-10. doi:10.1007/s00276-010-0660-2 Maybody M, Uszynski M, Morton E, Vitek JJ. Absence of the common carotid artery: a rare vascular anomaly. AJNR Am J Neuroradiol . Apr 2003;24(4):711-3. Malacarne V. Osserczioni sopra alcone arterie del corpo umano nello stratto preternaturale. Osservature Chir (Torino) . 1784;2:119. Lie TA. Congenital Anomalies of the Carotid Arteries . Excerpta Medica Foundation; 1968. Guha S, Grover V, Aiyer P, Dhull J. A unique case of right cervical aortic arch with anomalous left common carotid artery and absent right common carotid artery. Ann Med Surg (Lond) . Aug 2016;9:58-60. doi:10.1016/j.amsu.2016.06.013 Goyal S, Sinha AK. A rare case of absent left common carotid artery with bovine origin of the left external carotid artery. J Neurointerv Surg . May 2017;9(5):e20. doi:10.1136/neurintsurg-2016-012540.rep Yang SK, Zhang A, Hazany S, Huang J, Hathout GM. MR angiographic findings of aberrant right subclavian artery with agenesis of the left common carotid artery and anomalous origin of the vertebral arteries. Clin Imaging . Apr 2022;84:31-35. doi:10.1016/j.clinimag.2022.01.001 Rossitti S, Raininko R. Absence of the common carotid artery in a patient with a persistent trigeminal artery variant. Clin Radiol . Jan 2001;56(1):79-81. doi:10.1053/crad.1999.0276 Onbas O, Olgun H, Ceviz N, Ors R, Okur A. Interrupted aortic arch associated with absence of left common carotid artery: imaging with MDCT. Cardiovasc Intervent Radiol . May-Jun 2006;29(3):429-31. doi:10.1007/s00270-004-0291-2 Roberts LK, Gerald B. Absence of both common carotid arteries. AJR Am J Roentgenol . May 1978;130(5):981-2. doi:10.2214/ajr.130.5.981 Wood EA, Malgor RD, Labropoulos N. Diagnosing common carotid artery agenesis using duplex ultrasound. Vasc Endovascular Surg . Nov 2011;45(8):727-32. doi:10.1177/1538574411418013 Lale P, Toprak U, Yagiz G, Kaya T, Uyank S. Variations in the Branching Pattern of the Aortic Arch Detected with Computerized Tomography Angiography. 2014; Hanneman K, Newman B, Chan F. Congenital Variants and Anomalies of the Aortic Arch. Radiographics . Jan-Feb 2017;37(1):32-51. doi:10.1148/rg.2017160033 Dungan DH, Heiserman JE. The carotid artery: embryology, normal anatomy, and physiology. Neuroimaging Clin N Am . Nov 1996;6(4):789-99. Monaco EA, 3rd, Jankowitz BT, Tyler-Kabara EC, Horowitz MB. Incidental discovery of an absent right common carotid artery demonstrated by digital subtraction angiography and magnetic resonance angiography. Klin Neuroradiol . Aug 2009;19(3):227-9. doi:10.1007/s00062-009-9011-2 Rosen RDB, B. Embryology, aortic arch. StatPearls [Internet] . StatPearls Publishing; 2023. Omotoso BR, Harrichandparsad R, Lazarus L. A rare variation of five major vessels arising from the aortic arch with an absence of brachiocephalic trunk. Surg Radiol Anat . Jun 19 2025;47(1):161. doi:10.1007/s00276-025-03674-0 Pérez-García C, Pérez-Higueras A, Cabezudo García P. Left common carotid artery agenesis with bovine origin of the left internal carotid artery. Surg Radiol Anat . Oct 2018;40(10):1177-1180. doi:10.1007/s00276-018-2070-9 Moncada R, Shannon M, Miller R, White H, Friedman J, Shuford WH. The cervical aortic arch. American Journal of Roentgenology Radium Therapy & Nuclear Medicine . 1975;116(3):591-601. Boyd JD. Absence of the Right Common Carotid Artery. J Anat . Jul 1934;68(Pt 4):551-7. Lasjaunias P, Théron J, Moret J. The occipital artery. Anatomy--normal arteriographic aspects--embryological significance. Neuroradiology . Mar 29 1978;15(1):31-7. doi:10.1007/bf00327443 Geibprasert S, Pongpech S, Armstrong D, Krings T. Dangerous extracranial-intracranial anastomoses and supply to the cranial nerves: vessels the neurointerventionalist needs to know. AJNR Am J Neuroradiol . Sep 2009;30(8):1459-68. doi:10.3174/ajnr.A1500 Woodruff WW, 3rd, Strunsky VP, Brown NJ. Separate origins of the left internal and external carotid arteries directly from the aortic arch: duplex sonographic findings. J Ultrasound Med . Nov 1995;14(11):867-9. doi:10.7863/jum.1995.14.11.867 Yim SJ, Ryu JH, Baik JS, Kim JY, Park JH, Han SW. Common carotid artery agenesis: duplex ultrasonographic findings. J Clin Neurol . Sep 2009;5(3):149-50. doi:10.3988/jcn.2009.5.3.149 Ulger FE, Ulger A, Colak M. Absence of the right common carotid artery: Doppler ultrasonographic and MR angiographic findings. Vascular . Oct 2014;22(5):364-7. doi:10.1177/1708538113516316 Hopper W, Row H, West C, Reslan O. Systematic review of clinical literature for absent common carotid artery. J Vasc Surg Cases Innov Tech . Feb 2026;12(1):102039. doi:10.1016/j.jvscit.2025.102039 Additional Declarations No competing interests reported. Cite Share Download PDF Status: Under Revision Version 1 posted Editorial decision: Revision requested 28 Apr, 2026 Reviews received at journal 27 Apr, 2026 Reviews received at journal 27 Apr, 2026 Reviewers agreed at journal 27 Apr, 2026 Reviewers agreed at journal 27 Apr, 2026 Reviewers agreed at journal 27 Apr, 2026 Reviews received at journal 25 Apr, 2026 Reviewers agreed at journal 25 Apr, 2026 Reviewers agreed at journal 23 Apr, 2026 Reviewers invited by journal 23 Apr, 2026 Editor invited by journal 07 Apr, 2026 Editor assigned by journal 03 Apr, 2026 Submission checks completed at journal 03 Apr, 2026 First submitted to journal 30 Mar, 2026 You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. 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Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-9263858","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Case Report","associatedPublications":[],"authors":[{"id":630912104,"identity":"437df271-9f1a-4c5f-a849-3a6c6a10397f","order_by":0,"name":"Jinguang Zhou","email":"","orcid":"","institution":"The Third Xiangya Hospital of Central South University","correspondingAuthor":false,"prefix":"","firstName":"Jinguang","middleName":"","lastName":"Zhou","suffix":""},{"id":630912105,"identity":"41165c50-bbd5-4955-9354-4b30064d1c9d","order_by":1,"name":"Yongfeng Zhao","email":"","orcid":"","institution":"The Third Xiangya Hospital of Central South University","correspondingAuthor":false,"prefix":"","firstName":"Yongfeng","middleName":"","lastName":"Zhao","suffix":""},{"id":630912106,"identity":"f842befe-b0e7-462e-b016-a1c2e3d008af","order_by":2,"name":"Yunxia huang","email":"","orcid":"","institution":"The Third Xiangya Hospital of Central South University","correspondingAuthor":false,"prefix":"","firstName":"Yunxia","middleName":"","lastName":"huang","suffix":""},{"id":630912107,"identity":"1b2d6ee1-64a3-44cf-85e1-e57d70c46d27","order_by":3,"name":"Ping Zhou","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAA8klEQVRIiWNgGAWjYDACCRBhwMDAxszYcOBjA4jH2HiAKC187M0HH85sAPGBeglrAQI5nmPJxrwNED5eLfKzm49JFxTcsWuTyDGTtt1hU6fbfhhoS41NNC4tjHOOpUnPMHiWDNaSeyZNwuxMIlDLsbTcBhxamEEqeQwOJ7OBtbQdljA7ANTC2HAYpxY2FC2WIC3nH+LXwgPVYscG8j4jSMsNArZISKQlW88wOJzABgrk3rY0yW03gLYk4PGL/Izkg7cL/hy2l28GRsfPNht+s/PpDx98qLHBqQUcBECciKogAY9ymBZ7AmpGwSgYBaNgJAMAU7Vdki6pi6wAAAAASUVORK5CYII=","orcid":"","institution":"The Third Xiangya Hospital of Central South University","correspondingAuthor":true,"prefix":"","firstName":"Ping","middleName":"","lastName":"Zhou","suffix":""}],"badges":[],"createdAt":"2026-03-30 07:54:32","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-9263858/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-9263858/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":108725787,"identity":"21e86bd4-2877-4c9e-9efa-b470f42a84d6","added_by":"auto","created_at":"2026-05-07 16:58:26","extension":"png","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":5118567,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003eUltrasonography of the neck vessels.\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eA–B: gray-scale ultrasonography in longitudinal and transverse views demonstrating absence of the left common carotid artery, with visualization of a normal carotid bifurcation region, internal jugular vein, and vagus nerve. C–F: Color Doppler imaging showing flow patterns in the internal carotid artery, external carotid artery, and superior thyroid artery. Reversed flow is observed in the external carotid artery and superior thyroid artery, whereas the internal carotid artery demonstrates preserved antegrade low-resistance flow. Abbreviations: VN, vagus nerve; IJV, internal jugular vein; STA, superior thyroid artery.\u003c/p\u003e","description":"","filename":"Figure1.Ultrasonographyoftheneckvessels..png","url":"https://assets-eu.researchsquare.com/files/rs-9263858/v1/d617fe9c18c5c38e88b860d6.png"},{"id":108806476,"identity":"e26d9fee-6aa3-4a0b-ae5d-8b5d83268474","added_by":"auto","created_at":"2026-05-08 15:28:40","extension":"png","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":6164395,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003eComputed tomography angiography of the cervical and aortic arch vessels.\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eA: Absence of the brachiocephalic artery, with the aortic arch giving rise sequentially from right to left to the RCCA, RSA, and LSA. B: Absence of the LCCA, with the left ICA and ECA lacking separate origins. C: Marked dilation of the left DCA compared with the contralateral side. D: Extensive collateral vessels forming a tortuous anastomotic network around the left carotid bifurcation. Abbreviations: DCA, deep cervical artery.\u003c/p\u003e","description":"","filename":"Figure2.Computedtomographyangiographyofthecervicalandaorticarchvessels..png","url":"https://assets-eu.researchsquare.com/files/rs-9263858/v1/6b6740934ed5c6b3e462a24b.png"},{"id":108810046,"identity":"e6ae6dc0-77ff-4ab6-a7f4-026eac65c0a8","added_by":"auto","created_at":"2026-05-08 15:57:12","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":16838945,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-9263858/v1/42680a85-94bf-43f2-9964-f15d1c742e02.pdf"}],"financialInterests":"No competing interests reported.","formattedTitle":"Absence of the Left Common Carotid Artery with Internal and External Carotid Arteries Lacking Separate Origins: A Rare Case Report and Review of the Literature","fulltext":[{"header":"Background","content":"\u003cp\u003eAbsence of the common carotid artery (ACCA) is an extremely rare vascular anomaly. From its first description in 1784 to 2019, only 87 cases were reported\u003csup\u003e1\u003c/sup\u003e. A recent review expanded the total number of documented cases to 122\u003csup\u003e2\u003c/sup\u003e. ACCA is typically associated with independent origins of the external and internal carotid arteries, whereas cases lacking separate origins are extremely rare, with fewer than ten reported previously\u003csup\u003e3\u0026ndash;9\u003c/sup\u003e. This anatomical variation is usually asymptomatic and is most often detected incidentally during autopsy or imaging performed for unrelated clinical conditions, with no apparent sex predilection\u003csup\u003e10\u003c/sup\u003e. Here, we report a rare case involving absence of the left common carotid artery (CCA) and brachiocephalic artery (BA), combined with left internal carotid artery (ICA) and left external carotid artery (ECA) without independent origins.\u003c/p\u003e"},{"header":"Case presentation","content":"\u003cp\u003eA 24-year-old male presented to our hospital for further evaluation of scoliosis. He had no significant past medical history or family history, and his general condition was stable with stable vital signs.\u003c/p\u003e \u003cp\u003eNeck ultrasonography \u003cb\u003e(\u003c/b\u003eFig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003e\u003cb\u003e)\u003c/b\u003e revealed absence of the left CCA. The left ICA and ECA demonstrated normal course and intact lumens, with multiple collateral vessels observed at the carotid bifurcation. Color Doppler flow imaging showed retrograde flow in the left ECA, with only minimal antegrade flow detectable during late diastole, and a reversed flow waveform in the left superior thyroid artery. Further evaluation with computed tomography angiography \u003cb\u003e(\u003c/b\u003eFig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003e\u003cb\u003e)\u003c/b\u003e of the head and neck demonstrated absence of the left CCA and BA. The aortic arch gave rise sequentially to the right CCA, right subclavian artery (RSA), and left subclavian artery (LSA). The bifurcation of the left carotid artery was located at the level of the C4 vertebral body, with abundant collateral vessels observed around the bifurcation. The left deep cervical artery was dilated and formed a tortuous anastomotic network with the occipital arteries and vertebral arteries at the level of the C2 vertebral body. The intracranial arteries demonstrated normal configuration and course, with no evidence of significant stenosis, dilation, aneurysm, or other vascular malformations.\u003c/p\u003e \u003cp\u003eDespite the absence of the left CCA and BA, the patient remained asymptomatic and required no specific intervention. However, after discussion, the patient chose to defer surgical correction of scoliosis.\u003c/p\u003e \u003cp\u003eA\u0026ndash;B: gray-scale ultrasonography in longitudinal and transverse views demonstrating absence of the left common carotid artery, with visualization of a normal carotid bifurcation region, internal jugular vein, and vagus nerve. C\u0026ndash;F: Color Doppler imaging showing flow patterns in the internal carotid artery, external carotid artery, and superior thyroid artery. Reversed flow is observed in the external carotid artery and superior thyroid artery, whereas the internal carotid artery demonstrates preserved antegrade low-resistance flow. Abbreviations: VN, vagus nerve; IJV, internal jugular vein; STA, superior thyroid artery.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003eA: Absence of the brachiocephalic artery, with the aortic arch giving rise sequentially from right to left to the RCCA, RSA, and LSA. B: Absence of the LCCA, with the left ICA and ECA lacking separate origins. C: Marked dilation of the left DCA compared with the contralateral side. D: Extensive collateral vessels forming a tortuous anastomotic network around the left carotid bifurcation. Abbreviations: DCA, deep cervical artery.\u003c/p\u003e "},{"header":"Discussion and conclusion","content":"\u003cdiv id=\"Sec3\" class=\"Section2\"\u003e\u003cp\u003eACCA is an extremely rare anatomical anomaly. The first case was reported by Malacarne in 1784\u003csup\u003e11\u003c/sup\u003e. Up to 2019, only 87 cases had been documented \u003csup\u003e1\u003c/sup\u003e, and a recent review expanded the total number to 122\u003csup\u003e2\u003c/sup\u003e. This anomaly shows no significant lateral or sex predilection\u003csup\u003e12\u003c/sup\u003e. Patients are typically asymptomatic unless associated vascular abnormalities are present.\u003c/p\u003e \u003cp\u003eVarious vascular abnormalities have been reported to be associated with ACCA, including, but not limited to, cervical aortic arch, double aortic arch, right-sided aortic arch, interrupted aortic arch, intracranial aneurysms, internal carotid artery aneurysms, aberrant right subclavian artery, cerebral venous sinus thrombosis, persistent trigeminal artery, and persistent proatlantal intersegmental artery\u003csup\u003e4,8,9,13\u0026ndash;18\u003c/sup\u003e. Wood retrospectively reviewed 17,500 patients over a 15-year period and identified three cases, corresponding to an estimated incidence of approximately 0.017%\u003csup\u003e19\u003c/sup\u003e. Given its typically asymptomatic presentation, ACCA is most often detected incidentally during diagnostic or therapeutic procedures, making its true prevalence difficult to ascertain.\u003c/p\u003e \u003cp\u003eIn the typical anatomy, the aortic arch gives rise sequentially from right to left to the BA, left CCA, and LSA. This classic three-branch configuration is observed in approximately 87.5% of individuals\u003csup\u003e20\u003c/sup\u003e. ACCA is most commonly accompanied by independent origins of the internal and external carotid arteries. In a review of 87 cases, Vasovic reported that four-branch aortic arches were more frequently observed in patients with left ACCA, with the left ICA and ECA often originating directly from the aortic arch. Conversely, three-branch aortic arches were more common in patients with right ACCA, in which the right ICA and ECA frequently originated directly from the BA. Interestingly, in the present case, both the BA and left CCA were absent, and the left ICA and ECA were present without separate origins. Although the aortic arch gave rise to three branches, it did not conform to the typical three-branch pattern, instead giving rise sequentially to the right CCA, RSA, and LSA.\u003c/p\u003e \u003cp\u003eThis anomaly may be related to developmental abnormalities of the aortic arch system during the embryonic period. During early embryogenesis, the aortic arches and their branches develop from the ventral and dorsal aortae, together with the six paired pharyngeal aortic arteries situated between them\u003csup\u003e21\u003c/sup\u003e. The dorsal aortic segment between the third and fourth pharyngeal aortic arteries, known as the ductus caroticus. normally regresses by the sixth week of development or when the embryo measures 12\u0026ndash;14 mm \u003csup\u003e22\u003c/sup\u003e. The CCA develops from the aortic sac and the proximal segment of the third aortic arch, with the distal portion of the third arch continuing as the proximal ICA\u003csup\u003e21\u003c/sup\u003e. The ECA form by migration of the ventral pharyngeal arteries from the aortic sac to the third arch\u003csup\u003e23\u003c/sup\u003e. The aortic sac is the first portion of the aorta to develop. It later forms a right and a left horn. The right horn forms the BA, while the left horn, together with the stem of the aortic sac, forms part of the aortic arch proximal to the BA\u003csup\u003e24\u003c/sup\u003e. Incomplete development or regression of the right horn may result in absence of the BA, leading to the RSA and right CCA arising directly from the aortic arch \u003csup\u003e25\u003c/sup\u003e. Degeneration of the third aortic arch with persistence of the ductus caroticus\u003csup\u003e26\u003c/sup\u003e, or degeneration of the fourth arch together with persistence of the third arch and ductus caroticus\u003csup\u003e27\u003c/sup\u003e, has been proposed to result in the ICA and ECA arising independently; the latter scenario is often associated with a cervical aortic arch. Another hypothesis suggests that when the origin of the ECA is sufficiently distal from the caudal end of the third arch, the CCA may fail to develop\u003csup\u003e28\u003c/sup\u003e. However, in the present case, ACCA was not attributable to independent origins of the ICA and ECA. Instead, it appears to result from a lack of connection between the aortic and cervical arterial systems. Kwak suggested that this may be due to abnormal regression of the aortic sac or the proximal third aortic arch, which preserves the carotid bifurcation but prevents the formation of a complete CCA\u003csup\u003e3\u003c/sup\u003e.\u003c/p\u003e \u003cp\u003eThe occipital artery maintains communication between the external carotid artery system and the vertebral artery via the posterior anastomotic radicular branches \u003csup\u003e29\u003c/sup\u003e. The deep cervical artery, originating from the costocervical trunk, serves as a major anastomotic pathway to the vertebral artery at the C2\u0026ndash;C4 levels \u003csup\u003e30\u003c/sup\u003e. Additionally, the external carotid artery can form a stable collateral connection with the deep cervical artery through the deep branch of the occipital artery. Consequently, the occipital\u0026ndash;deep cervical\u0026ndash;vertebral arterial network functions as a compensatory pathway in cases of carotid developmental anomalies or occlusive lesions, enhancing blood flow to maintain posterior circulation and intracranial perfusion. This extensive collateral system likely accounts for the absence of clinical symptoms in the present patient.\u003c/p\u003e \u003cp\u003eColor Doppler ultrasonography is the first-line modality for the diagnosis of ACCA, providing clues to CCA absence or carotid bifurcation anomalies\u003csup\u003e31\u0026ndash;33\u003c/sup\u003e. The presence of an absent CCA does not significantly affect the spectral Doppler waveform characteristics of the ICA and ECA, which typically demonstrate low-resistance and high-resistance flow patterns, respectively\u003csup\u003e31\u003c/sup\u003e. computed tomography angiography combined with multiplanar and three-dimensional reconstructions allows precise evaluation of the cervical vascular anatomy, variant arterial origins, and intracranial vasculature, offering a more comprehensive imaging assessment\u003csup\u003e19\u003c/sup\u003e.\u003c/p\u003e \u003cp\u003eSuch vascular variations can lead to hemodynamic alterations, including increased blood flow and changes in flow direction, resulting in additional hemodynamic stress and potentially increasing the risk of cerebrovascular events. Patients with these anomalies are generally considered to have a higher risk of adverse events\u003csup\u003e1\u003c/sup\u003e. In a review of 63 cases of CCA absence, Hopper reported that more than 50% of patients experienced cerebrovascular-related symptoms\u003csup\u003e34\u003c/sup\u003e. For asymptomatic individuals, there is currently no recommendation for intervention or surgical correction of this developmental anomaly.\u003c/p\u003e \u003cp\u003eWe report a rare case of left ACCA without separate origins of the left ICA and ECA. This anatomical variant is typically asymptomatic. However, accurate recognition of such vascular anomalies is clinically important, as it can guide endovascular procedures involving the aorta and cerebral vessels, reduce the risk of iatrogenic injury due to atypical vascular routes, and assist in assessing the risk of concomitant cerebrovascular diseases.\u003c/p\u003e \u003c/div\u003e"},{"header":"Abbreviations","content":"\u003cp\u003eACCA, absence of the common carotid artery; CCA, common carotid artery; ICA, internal carotid artery; ECA, external carotid artery; BA, brachiocephalic artery; RSA, right subclavian artery; LSA, left subclavian artery.\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003e\u003cstrong\u003eEthics approval and consent to participate\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThis study was approved by the Ethics Committee of The Third Xiangya Hospital of Central South University (Approval No. 251088). Written informed consent was obtained from the patient for participation in this study.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConsent for publication\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eWritten informed consent was obtained from the patient for publication of the clinical data and accompanying images.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAvailability of data and materials\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe datasets used and/or analysed during the current study are available from the corresponding author on reasonable request.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eCompeting interests\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe authors declare no conflict of interest.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eFunding\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThis work was supported by National Natural Science Foundation of China [81871367]. The funding assisted in the collection of clinical data and publication fees.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAuthors\u0026apos; contributions\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eJ. Zhou performed data analyses and wrote the manuscript. Y. Huang participated in data collection and patient follow-up. Y. Zhao conducted the clinical diagnosis and data collection. P. Zhou critically revised the manuscript. All authors read and approved the final manuscript.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAcknowledgements\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eNone.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\n\u003cli\u003eVasović L, Trandafilović M, Vlajković S. Congenital Aplasia of the Common Carotid Artery: A Comprehensive Review. \u003cem\u003eBiomed Res Int\u003c/em\u003e. 2019;2019:9896138. doi:10.1155/2019/9896138\u003c/li\u003e\n\u003cli\u003eRamputi L, Mazzaccaro D, Tissir K, et al. 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Absence of the Right Common Carotid Artery. \u003cem\u003eJ Anat\u003c/em\u003e. Jul 1934;68(Pt 4):551-7.\u003c/li\u003e\n\u003cli\u003eLasjaunias P, Th\u0026eacute;ron J, Moret J. The occipital artery. Anatomy--normal arteriographic aspects--embryological significance. \u003cem\u003eNeuroradiology\u003c/em\u003e. Mar 29 1978;15(1):31-7. doi:10.1007/bf00327443\u003c/li\u003e\n\u003cli\u003eGeibprasert S, Pongpech S, Armstrong D, Krings T. Dangerous extracranial-intracranial anastomoses and supply to the cranial nerves: vessels the neurointerventionalist needs to know. \u003cem\u003eAJNR Am J Neuroradiol\u003c/em\u003e. Sep 2009;30(8):1459-68. doi:10.3174/ajnr.A1500\u003c/li\u003e\n\u003cli\u003eWoodruff WW, 3rd, Strunsky VP, Brown NJ. Separate origins of the left internal and external carotid arteries directly from the aortic arch: duplex sonographic findings. \u003cem\u003eJ Ultrasound Med\u003c/em\u003e. Nov 1995;14(11):867-9. doi:10.7863/jum.1995.14.11.867\u003c/li\u003e\n\u003cli\u003eYim SJ, Ryu JH, Baik JS, Kim JY, Park JH, Han SW. Common carotid artery agenesis: duplex ultrasonographic findings. \u003cem\u003eJ Clin Neurol\u003c/em\u003e. Sep 2009;5(3):149-50. doi:10.3988/jcn.2009.5.3.149\u003c/li\u003e\n\u003cli\u003eUlger FE, Ulger A, Colak M. Absence of the right common carotid artery: Doppler ultrasonographic and MR angiographic findings. \u003cem\u003eVascular\u003c/em\u003e. Oct 2014;22(5):364-7. doi:10.1177/1708538113516316\u003c/li\u003e\n\u003cli\u003eHopper W, Row H, West C, Reslan O. Systematic review of clinical literature for absent common carotid artery. \u003cem\u003eJ Vasc Surg Cases Innov Tech\u003c/em\u003e. Feb 2026;12(1):102039. doi:10.1016/j.jvscit.2025.102039\u003c/li\u003e\n\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":false,"highlight":"","institution":"","isAcceptedByJournal":false,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"bmc-cardiovascular-disorders","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"bcar","sideBox":"Learn more about [BMC Cardiovascular Disorders](http://bmccardiovascdisord.biomedcentral.com/)","snPcode":"","submissionUrl":"https://www.editorialmanager.com/bcar/default.aspx","title":"BMC Cardiovascular Disorders","twitterHandle":"BMC_series","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"em","reportingPortfolio":"BMC Series","inReviewEnabled":true,"inReviewRevisionsEnabled":true},"keywords":"Absence of the common carotid artery, Collateral circulation, Computed tomography angiography, Ultrasound, Embryology.","lastPublishedDoi":"10.21203/rs.3.rs-9263858/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-9263858/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003ch2\u003eBackground\u003c/h2\u003e \u003cp\u003eAbsence of the common carotid artery is a rare vascular anomaly. Patients are typically asymptomatic unless accompanied by other vascular abnormalities. This condition is usually associated with independent origins of the internal and external carotid arteries, whereas cases without separate origins are particularly rare, with fewer than ten reported in the literature.\u003c/p\u003e\u003ch2\u003eCase presentation\u003c/h2\u003e \u003cp\u003eA 24-year-old man was incidentally found to have absence of the left common carotid artery during imaging evaluation for scoliosis. Ultrasonography and computed tomography angiography demonstrated absence of the left common carotid and brachiocephalic arteries, with the left internal and external carotid arteries lacking separate origins. Extensive collateral circulation was observed via the deep cervical, occipital, and vertebral arteries, accompanied by retrograde flow in the left external carotid and superior thyroid arteries. The patient was asymptomatic and did not require vascular intervention.\u003c/p\u003e\u003ch2\u003eConclusions\u003c/h2\u003e \u003cp\u003eUltrasonography is the first-line diagnostic modality, while computed tomography angiography with three-dimensional reconstruction provides complementary and comprehensive anatomical assessment. Accurate recognition of such vascular anomalies is crucial, as it can reduce the risk of iatrogenic injury associated with atypical vascular pathways and facilitate evaluation of potential cerebrovascular complications.\u003c/p\u003e\u003ch2\u003eClinical trial number\u003c/h2\u003e \u003cp\u003eNot applicable\u003c/p\u003e","manuscriptTitle":"Absence of the Left Common Carotid Artery with Internal and External Carotid Arteries Lacking Separate Origins: A Rare Case Report and Review of the Literature","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2026-05-07 16:58:22","doi":"10.21203/rs.3.rs-9263858/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"decision","content":"Revision requested","date":"2026-04-28T09:06:35+00:00","index":"","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2026-04-27T20:30:33+00:00","index":"hide","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2026-04-27T14:28:56+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"53794344922086979937864507202181220052","date":"2026-04-27T14:26:06+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"73570351516057792210928032840671846378","date":"2026-04-27T12:49:15+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"140823217953991862686069753717632399938","date":"2026-04-27T11:35:49+00:00","index":"hide","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2026-04-26T01:38:30+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"33665762145778211042819196733529911516","date":"2026-04-25T12:39:51+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"133877217926731664149441545168945309581","date":"2026-04-23T05:17:19+00:00","index":"hide","fulltext":""},{"type":"reviewersInvited","content":"","date":"2026-04-23T05:01:31+00:00","index":"","fulltext":""},{"type":"editorInvited","content":"","date":"2026-04-07T13:34:20+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2026-04-03T11:13:29+00:00","index":"","fulltext":""},{"type":"checksComplete","content":"","date":"2026-04-03T11:13:09+00:00","index":"","fulltext":""},{"type":"submitted","content":"BMC Cardiovascular Disorders","date":"2026-03-30T07:47:55+00:00","index":"","fulltext":""}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"bmc-cardiovascular-disorders","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"bcar","sideBox":"Learn more about [BMC Cardiovascular Disorders](http://bmccardiovascdisord.biomedcentral.com/)","snPcode":"","submissionUrl":"https://www.editorialmanager.com/bcar/default.aspx","title":"BMC Cardiovascular Disorders","twitterHandle":"BMC_series","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"em","reportingPortfolio":"BMC Series","inReviewEnabled":true,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"b7c00154-48c6-4a85-9936-4c7b51625433","owner":[],"postedDate":"May 7th, 2026","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"in-revision","subjectAreas":[],"tags":[],"updatedAt":"2026-05-07T16:58:22+00:00","versionOfRecord":[],"versionCreatedAt":"2026-05-07 16:58:22","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-9263858","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-9263858","identity":"rs-9263858","version":["v1"]},"buildId":"XKTyCvWXoU3ODBz1xrDgd","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}