Below is an instruction from Human. Write a response.
    ### Instruction:
    What is (are) Progressive hemifacial atrophy ?
    ### Response:
    Progressive hemifacial atrophy, or Parry-Romberg syndrome, is a condition that causes the breakdown of the skin and soft tissues of half of the face. Symptoms and severity vary from person to person. This condition tends to begin in childhood between the ages of 5 and 15 years, and worsen over the course of 2 to 10 years before stabilizing.
    