Hemifacial atrophy causes one side of the face to become smaller, leading to facial asymmetry. Surgeons often restore facial volume using either autologous fat grafting or free-flap reconstruction. However, it is not fully clear how much facial symmetry improves after surgery when measured objectively using two-dimensional (2D) photographs and three-dimensional (3D) surface scans.

This is a single-center, retrospective observational study of patients with hemifacial atrophy treated between January 2020 and December 2023 at [Plastic Surgery Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College]. We will quantify facial symmetry before surgery and at the first follow-up visit occurring at or beyond 6 months after the initial surgery. Symmetry outcomes will be assessed using standardized 2D photographs for all included patients, and 3D surface scans for a subset of patients. Complications will also be assessed at the first ≥6-month follow-up visit. We will compare changes in symmetry between patients treated with fat grafting and those treated with free-flap reconstruction.

Inclusion Criteria:

Diagnosis of hemifacial atrophy (Parry-Romberg syndrome).

Underwent initial soft-tissue augmentation with either autologous fat grafting or free-flap reconstruction at the study center between January 2020 and December 2023.

Availability of standardized preoperative assessment and postoperative assessment at the first follow-up visit occurring ≥6 months after surgery (2D photographs required).

Exclusion Criteria:

Follow-up <6 months after the initial surgery.

Missing key imaging/photographic data required for outcome assessment.

Any additional facial augmentation or revision procedure performed before the first ≥6-month follow-up visit.

Patients with hemifacial atrophy treated at a single center between January 2020 and December 2023 who underwent initial facial volume restoration using autologous fat grafting or free-flap reconstruction. Outcomes were assessed preoperatively and at the first follow-up visit ≥6 months postoperatively. Three-dimensional surface scan analysis was performed in a subset with available 3D data.