Photoacoustic Imaging for Measuring Tumors and Normal Tissue in Patients With Head and Neck Cancer

Inclusion Criteria: * No restriction on race or ethnic background * Subject must understand the investigational nature of the study and sign an independent ethics committee/institutional review board approved written informed consent prior to receiving any study related procedure * FOR CANCER PATIENTS IN THE H\&N RADIATION GROUP (PART I): * Biopsy-confirmed diagnosis of head and neck squamous cell carcinoma (HNSCC) getting chemoradiation therapy * Presence of neck nodes or laryngeal tumor superficial enough (within 2-3 cm of skin surface) to allow imaging by photoacoustic ultrasound (PA-US) * FOR ALTENS PATIENTS (PART II): * History of prior radiation therapy with xerostomia requiring ALTENS Exclusion Criteria: * Uncontrolled intercurrent illness including, but not limited to, ongoing or active infection, symptomatic congestive heart failure, unstable angina pectoris, cardiac arrhythmia, or psychiatric illness/social situations that would limit compliance with study requirements * Unwilling or unable to follow protocol requirements or provide consent * Any condition which in the Investigator?s opinion deems the subject an unsuitable candidate to undergo imaging procedure