Can a simple home device stop facial swelling before it starts?

This study is testing whether starting a simple home therapy early can prevent painful facial and neck swelling (lymphedema) in people who have been treated for head and neck cancer. Researchers will use a special imaging scan to spot early signs of swelling and then have one group use a daily compression device at home for a year, while another group receives standard care. They will compare the two groups to see if the early treatment prevents the swelling from developing or getting worse.