Objective:How to increase the long-term retention rate of autologous fat grafting has been widely discussed.This study aimed to evaluate long-termfat graft retention rates for the most widely used fat processing methods in the area of facial esthetic surgery,including centrifugation,filration,and sedimentation,using three-dimensional (3D) imaging.Data Sources:PubMed,Embase,Wiley/Cochrane Library,and Web of Science databases were comprehensively searched from inception to July 2018 according to the guidelines of the American Society of Plastic Surgeons Fat Graft Task Force Assessment Methodology.Study Selection:Articles were screened using predetermined inclusion and exclusion criteria.Data collected included patient characteristics,follow-up devices,fat grafting techniques,and clinical outcomes.Patient cohorts were pooled,and fat graft retention rates were calculated.Complications were summarized according to different clinical characteristics.Results:Of 77 articles,10 clinical studies met the inclusion criteria and reported quantified measurement outcomes with 3D imaging which provide precise volumetric data with approximately 2％ standard deviation compared to real volumes.Data of 515 patents were included.Fat grafting retention varied from 21％ to 82％.We found filtration and centrifugation techniques could result in better retention outcomes.However,retention varied within each processing technique,with no significant difference among the 3 techniques.Twenty-two complications were reported among 515 patients,including donor-site hematoma (1 case),mild postoperative erythema (2 cases),mild volumetric asymmetries (2 cases),chronic edema (2 cases),overcorrection (2 cases),skin irregularity (6 cases),and headache or dysesthesia (7 cases).Conclusions:Filtration and centrifugation techniques may result in better fat grafting retention outcomes than gravity sedimentation;however,more accurate statistical evidence is needed.Controversies continue to exist with respect to the performance of the different fat-processing techniques in fat graft retention.