Anatomical Relationship Between Carotid Artery and Hyoid Bone in Stenotic and Non-stenotic Carotids

Study Overview
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Brief Summary
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Ischaemic stroke is attributable to thromboembolism caused by carotid atherosclerotic disease in 18-25% of patients. Guidelines for prevention of stroke (especially carotid endarterectomy) in patients with carotid atherosclerotic plaque are based on the quantification of the degree of stenosis. The hyoid bone, in proximity to the carotid artery, has been implicated in the pathophysiology of carotid artery dissection, atherosclerotic carotid disease, and compressive syndromes. In atherosclerotic carotid disease, pressure on the carotid artery induced by these bone structures has been proposed to play a possible role in plaque formation and rupture, leading to stenosis, occlusion, or artery-to-artery embolism. In a recent ultrasound study, dynamic displacement of the carotid artery with interference of the hyoid bone during swallowing, named as flip-flop phenomenon (FFP) has been associated with carotid artery stenosis and stenosis-related stroke. Another study based on CTA assessment observed no association between hyoid-carotid distance and plaque thickness, stenosis, or progression of thickness/stenosis. In that study, in almost two-third of the patients CTA was performed for stroke/transient ischemic attack work-up, including a vast majority of patients with absence of carotid stenosis (median degree of carotid stenosis was 7%), and plaque-related stroke was not assessed. The objective of this study is to determine the anatomic hyoid-carotid interaction (ie, hyoid-carotid distance, carotid position relative to the hyoid bone, and hyoid morphology) based on CTA and its relation to the degree of carotid stenosis and stenosis-related stroke.

Official Title
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Anatomical Relationship Between Carotid Artery and Hyoid Bone in Stenotic and Non-stenotic Carotids: a Cohort Study of Symptomatic and Asymptomatic Carotid Endarterectomy Patients

Conditions
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Stenoses, Carotid, Stroke

Intervention / Treatment
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* Other: None, pure observational study


Participation Criteria
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Eligibility Criteria
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Patients followed at the University Hospital of Nîmes between November 2016 and March 2020 Age > 18 years Patients who underwent carotid endarterectomy for symptomatic or asymptomatic stenosis

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| stenotic carotid<br>patients with a stenotic carotid | Other: None, pure observational study<br>* None, pure observational study<br>|
| non stenotic carotid<br>patients with non stenotic carotid | Other: None, pure observational study<br>* None, pure observational study<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Distance hyoid-carotid artery | the closest distance between the hyoid bone and the outer vessel wall of the carotid artery(mm) | Base line, Day 0 | 
| Carotid artery portion closest to the hyoid bone | Depending on the level of the carotid bifurcation: common carotid artery [CCA], carotid bifurcation [CB], or internal carotid artery [ICA]) | Base line, Day 0 | 
| Carotid artery position in regard to ipsilateral greater horn of the hyoid | The position of the carotid artery in regard to the ipsilateral greater horn of the hyoid (expressed in angle degree, with 0 to 90° corresponding to the posterolateral carotid position, 90 to 180° to anterolateral, 0 to -90° to posteromedial position, and -90 to-180° to anteromedial carotid position) | Base line, Day 0 | 
| Hyoid bone morphology | Hyoid width (HW), hyoid length (HL), and hyoid circumferential length (HCL) | base line, day 0 | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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computed tomography, carotid, atherosclerotic, plaque, density, stroke