Progressive hemifacial atrophy (PHA; Parry-Romberg Syndrome) Clinical manifestations: Progressive atrophy of the skin and soft tissues of the head and face, with accumulation of craniofacial bone tissue in severe cases; usually occurs unilaterally and does not exceed the midline of the face, but in rare cases can also be seen on both sides of the face; the face A distinctive indentation on the face, clinically called “saber scar”; the lesion area may be accompanied by hyperpigmentation, hair changing from black to white; the motor function of the face is not affected. Criticality of disease: 1 star, mild; 2 stars, moderate; 3 stars, moderate: 1 star, does not affect study, work, life, only cause cosmetic changes. Treatment: Prefer autologous fat transplantation (minimally invasive, good efficacy, often requires 1~3 times), other treatments include: autologous fat fascial flap free transplantation, 3D printed facial prosthesis/autologous bone graft to reconstruct contours, etc. Treatment results: Obvious improvement and good results. Typical case 1: many years of disease with no facial bone involvement; after simple fat grafting, the facial appearance improved significantly, symmetry returned, and skin quality on the affected side improved.