Primary Objective: To determine the proportion of patients with clinically significant carotid artery stenosis (≥50% stenosis) in head and neck cancer survivors treated with head and neck radiotherapy.~Secondary Objectives:~To measure the intima-media thickness (IMT) of the carotid arteries in head and neck cancer survivors treated with head and neck radiotherapy.~To determine the proportion of patients with carotid intima-media thickness of at least 0.9 mm in head and neck cancer survivors treated with head and neck radiotherapy.~To determine the proportion of patients with carotid plaque of maximum thickness 2 mm or greater in head and neck cancer survivors treated with head and neck radiotherapy.~To determine the proportion of patients identified as having a high risk of cardiovascular events (relative risk 1.50 or greater) based on intima-media thickness measurements in head and neck cancer survivors treated with head and neck radiotherapy.~To describe the risk of significant carotid artery stenosis based on various clinical factors in head and neck cancer survivors treated with head and neck radiotherapy.~To determine the feasibility of carotid ultrasound in head and neck cancer survivors treated with head and neck radiotherapy.~To obtain preliminary data on the acceptability of carotid ultrasound among head and neck cancer survivors treated with head and neck radiotherapy.~To obtain preliminary data on barriers to potential carotid ultrasound screening in head and neck cancer survivors treated with head and neck radiotherapy.~To obtain preliminary data on stroke risk perception among head and neck cancer survivors treated with radiotherapy in head and neck cancer survivors treated with head and neck radiotherapy.
The purpose of this research study is to understand how radiation therapy may affect blood vessels in the neck called the carotid arteries. Investigators want to look at narrowing of the artery or thickening of the walls of the arteries.