Prospective Controlled Study of Buttock Fat Transfer Using Ultrasound and Photographic Measurements

A Bibliometric Analysis of the Top 100 Papers on Gluteal Augmentation

Background

Gluteoplasty or gluteal augmentation is a popular cosmetic procedure that is used to improve the volume, shape, and contour of the buttocks.

Objectives

This bibliometric analysis aims to characterize emerging research trends and to assess the methodological quality of the highest impact gluteoplasty research.

Methods

The 100 most-cited publications in gluteoplasty were identified on Web of Science, across all available journal years (from Inception to August 2023). Study details, including the citation count, main content focus, and outcome measures, were extracted and tabulated from each publication. Oxford Centre for Evidence Based Medicine level of evidence (LOE) of each study was assessed.

Results

The 100 most-cited publications regarding gluteoplasty were cited by a total of 2375 publications. Citations per publication ranged from 5 to 176 (mean 23.75 ± 25.86), with the highest-cited study being authored by Simonacci, discussing autologous fat grafting (n = 176). Most publications were LOE 5 (n = 55), representative of the large number of case series and reports. The number of publications for LOE 1, 2, 3, and 4 was 1, 9, 13, and 22, respectively. The main content focus was "surgical technique" in 38 publications, followed by "outcomes" (n = 34) and "risk factors/prognosis" (n = 10). Patient-reported outcome measures (PROMs) were used in 20 publications, and 33 publications reported aesthetic outcome measures.

Conclusions

This analysis demonstrates a need for improvement in research methodologies regarding gluteoplasty research. This advancement would be facilitated by robust, high-quality research through randomized control trials and multicenter studies, as well as the further development of validated PROMs for gluteoplasty.

Level of Evidence 2

Danger Zones of the Gluteal Anatomy: Improving the Safety Profile of the Gluteal Fat Grafting

INTRODUCTION

Knowledge of the vascular anatomy is critical to performing safe gluteal surgery. To date, only the course of the main blood vessels within the muscles has been outlined. These findings are based on MRI and CTA images that do not conform to a topographically standardized and normalized probability distribution.

OBJECTIVES

The aim of this study was to develop a three-dimensional mapping of the gluteal zones of high vascular density in relation to anatomical landmarks.

MATERIALS AND METHODS

This single-center retrospective cohort analysis comprised all consecutive patients who underwent cone-beam computed tomography (CBCT) scans between January 2016 and October 2021. The location of blood vessels in the gluteal region was allometrically normalized in relation to anatomical landmarks. Moreover, the caliber and area of the blood vessels were assessed.

RESULTS

CBCT scans of 32 patients with an average age of 64 ± 12 years (range 34-87 years) were included. Fifty-three percent were female. The median [IQR] caliber of the intramuscular gluteal vessels was 1.47 [1.15-1.88] mm, significantly greater than that of the subcutaneous vessels 1.09 [0.72-1.44] mm (p < 0.001). Vascular density was higher intramuscularly, as 4.5% of the area of the muscle was occupied by blood vessels, as opposed to 0.3% in the adipose tissue.

CONCLUSION

The analysis of the CBCT scans showed a higher vascular density and larger vessels intramuscularly. We, therefore, recommend the injection of autologous fat merely to the subcutaneous plane.

LEVEL OF EVIDENCE II

This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

Accurate Plane Fat Grafting in Gluteal Augmentation: An Anatomic Study

BACKGROUND

The safety of gluteal fat grafting is a global concern in plastic surgery.

OBJECTIVE

The goal of this study was to test whether fat grafting to the buttocks with Auto Stop Reach (ASR) technology prevents penetration from the subcutaneous space into the fascia and muscle layers of the buttocks.

METHODS

Fat transfer simulation was performed with blue dye on 8 fresh tissue cadaver buttocks by 3 board-certified plastic surgeons (S.S.K., S.C., B.W.). An open control was utilized to visualize the process in the different anatomic layers, and all of the other procedures were performed blindly, akin to live surgery. After blue dye transfer reached maximum capacity (ranging from 400-800 mL per buttock), dissection of the anatomical layers of the buttocks was performed to determine the plane(s) of injection.

RESULTS

Blue dye fat transfer injection to the buttocks did not penetrate the gluteal fascia or muscle layers from the subcutaneous space while using ASR.

CONCLUSIONS

Auto Stop Reach technology supports the safety of gluteal fat transfer in the subcutaneous space by board-certified plastic surgeons.

LEVEL OF EVIDENCE: 4

A Systematic Review of Electromagnetic Treatments for Body Contouring

BACKGROUND

Energy-based treatments include ultrasound, lasers, cryolipolysis, and radiofrequency. The most recent energy treatment for noninvasive body contouring is electromagnetic treatments-a hot topic in plastic surgery today. A systematic review to assess efficacy and safety has not been published.

METHODS

An electronic search was performed using PubMed to identify the literature describing electromagnetic treatments. Measurements from imaging studies were tabulated and compared.

RESULTS

Fourteen clinical studies were evaluated. Two studies included simultaneous radiofrequency treatments. In 11 studies, the Emsculpt device was used; in 2 studies, the Emsculpt-Neo device was used. One study included a sham group of patients. The usual protocol was 4 treatments given over a 2-week period. No complications were reported. Eight studies included abdominal measurement data obtained using magnetic resonance imaging, computed tomography, or ultrasound. Photographic results were typically modest. Photographs showing more dramatic results also showed unexplained reductions in untreated areas.Measurement variances were high. The mean reduction in fat thickness was 5.5 mm. The mean increment in muscle thickness was 2.2 mm. The mean decrease in muscle separation was 2.9 mm (P = 0.19). Early posttreatment ultrasound images in 1 study showed an echolucent muscle layer, compared with a more echodense layer at the baseline, consistent with tissue swelling after exercise. Almost all studies were authored by medical advisors for the device manufacturer.

DISCUSSION

Measurement data show small reductions in fat thickness, occurring almost immediately after the treatments. Adipocyte removal without tissue swelling would be unique among energy-based treatments. Similarly, muscle hypertrophy is not known to occur acutely after exercise; muscle swelling likely accounts for an early increment in muscle thickness. Any improvement in the diastasis recti is likely fictitious.

CONCLUSIONS

Electromagnetic treatments, either administered alone or in combination with radiofrequency, are safe. However, the evidence for efficacy is tenuous. Measured treatment effects are very small (<5 mm). Conflict of interest and publication bias are major factors in studies evaluating energy-based alternatives. The evidence-based physician may not be satisfied that an equivocal treatment benefit justifies the time and expense for patients.

Study on promoting the regeneration of grafted fat by cell-assisted lipotransfer

Background

Cell-assisted lipotransfer (CAL), a modified adipose-derived stromal/stem cells (ADSCs)-based approach for autologous fat grafting that is an ideal option for soft tissue augmentation, has many shortcomings in terms of retention and adverse effects. The objective of our study was to improve the treatment efficacy of CAL by adding fibroblasts.

Methods

ADSCs and fibroblasts were isolated from human adipose and dermal tissues, with fibroblasts identified by immunofluorescence and ADSCs identified by the multilineage differentiation method. We performed cell proliferation, apoptosis, migration, adipogenic, and hemangioendothelial differentiation experiments, qPCR and Western blotting analysis in co-cultures of fibroblasts and ADSCs. Subsequently, we conducted animal experiments with BALB/c nude mice. Masson's staining, immunofluorescence staining and ultrasound were used to analyze the occurrence of adverse reactions of the grafted fat, and CT and three-dimensional reconstruction were used to accurately evaluate the volume of the grafted fat.

Results

We found that the co-culture of fibroblasts and ADSCs promoted their mutual proliferation, adipogenic differentiation, hemangioendothelial differentiation and proliferation and migration of HUVECs. Fibroblasts inhibit the apoptosis of ADSCs. Moreover, in animal experiments, the autografted adipose group combined with ADSCs and fibroblasts had the least occurrence of oily cysts, and fat had the best form of survival.

Conclusions

We enhanced adipocyte regeneration and angiogenesis in ADSCs and fibroblast cells after adding fibroblasts to conventional CAL autologous fat grafts. In turn, the volume retention rate of the grafted fat is improved, and the adverse reactions are reduced.

Fat Grafting in Radiation-Induced Soft-Tissue Injury: A Narrative Review of the Clinical Evidence and Implications for Future Studies

SUMMARY

Radiation-induced changes in skin and soft tissue result in significant cosmetic and functional impairment with subsequent decrease in quality of life. Fat grafting has emerged as a therapy for radiation-induced soft-tissue injury, and this narrative review aims to evaluate the current clinical evidence regarding its efficacy. A review was conducted to examine the current clinical evidence of fat grafting as a therapy for radiation-induced injury to the skin and soft tissue and to outline the clinical outcomes that can be used to more consistently quantify chronic radiation-induced injury in future clinical studies. The current clinical evidence regarding the efficacy of fat grafting to treat radiation-induced injury of the skin and soft tissue suggests that fat grafting increases skin softness and pliability, induces volume restoration, improves hair growth in areas of alopecia, reduces pain, and improves cosmetic and functional outcomes. However, literature in this field is far from robust and mired by the retrospective nature of the studies, lack of adequate controls, and inherent limitations of small case series and cohorts. A series of actions have been identified to strengthen future clinical data, including the need for physical examination using a validated scale, appropriate imaging, skin biomechanics and microcirculation testing, and histologic analysis. In conclusion, radiation-induced soft-tissue injury is a significant health burden that can lead to severe functional and aesthetic sequelae. Although still in a preliminary research phase, there is promising clinical evidence demonstrating the benefits of fat grafting to treat chronic changes after radiation therapy. Future clinical studies will require larger cohorts, adequate controls, and consistent use of objective measurements.

Photographic Comparison of Malar Projection in 100 Facelift Patients Treated with and without Fat Injection

Facelifts are frequently combined with fat injection to restore volume. However, the efficacy of simultaneous fat grafting has not been objectively evaluated in a large number of patients that includes a control group. This study was undertaken to fill this gap in our knowledge base.

Near-circumferential Lower Body Lift: A Review of 40 Outpatient Procedures

Lower body lift surgery has increased in popularity. A circumferential body lift or belt lipectomy is often recommended to treat skin redundancy. A drawback for this procedure is the midline scar bridging the lower back causing elongation of the gluteal cleft. Autoaugmentation methods have not been shown to provide a net increase in buttock volume.

Gluteal Augmentation With Fat: Retrospective Safety Study and Literature Review

BACKGROUND

Use of gluteal augmentation with fat increased by 3267% from 2002 to 2015, and the rate of death is highest compared with other aesthetic procedures: 1 in 3448 patients dies, compared with 1 in 55,000.

OBJECTIVES

To retrospectively investigate patients who underwent this procedure at Oslo Plastic Surgery Clinic, to review international data to determine factors causing mortality, and to provide guidelines for safety.

METHODS

Patient data were searched for reason for the procedure, assessment of patients, techniques performed, and safety measures used. In 60 cases, a vibration machine was used for fat harvesting. Review of the international literature, with special emphasis on fatal complications, was performed on Medline, Google Scholar, and PubMed.

RESULTS

Mean patient age was 32 years. Mean amount of grafted fat was 422 mL (range, 210-850 mL). Sedation, local and tumescent anesthesia were used in all patients, with mobilization directly after surgery. Mean operation time was 89 minutes. Eighteen patients required a second surgery. Minor complications occurred in 8 patients. Average follow-up was 8 months. Ninety percent of patients were satisfied. Review of international literature showed that the main reason for death in 2015 was fat lung embolism related to muscular and submuscular grafting.

CONCLUSIONS

Gluteal augmentation with fat is one of the most popular procedures, with an internationally high mortality rate. Patient safety is a priority, and preventive measures should improve safety because appropriate patient selection, avoiding muscular and submuscular grafting, avoiding infragluteal incision, moderate grafted volume, and direct postoperative mobilization are essential.

LEVEL OF EVIDENCE: 4

The Expanding Role of Diagnostic Ultrasound in Plastic Surgery

Supplemental Digital Content is available in the text.

Background:

Ultrasound in plastic surgery is quickly finding new applications. Ultrasound surveillance may replace ineffective individual risk stratification and chemoprophylaxis for deep venous thromboses. Abdominal penetration can be a catastrophic complication of liposuction. Preoperative screening for fascial defects may reduce risk. Limiting buttock fat injections to the subcutaneous plane is critical for patient safety, but it is difficult to know one’s injection plane.

Methods:

The author’s use of diagnostic ultrasound was evaluated from May 2017 to May 2018. Ultrasound scans were used routinely to detect deep venous thromboses. Patients undergoing abdominal liposuction and/or abdominoplasty were scanned for possible hernias. Other common applications included the evaluation of breast implants, breast masses, and seroma management. The device was used in surgery in 3 patients to assess the plane of buttock fat injection.

Results:

One thousand ultrasound scans were performed during the 1-year study period. A distal deep venous thrombosis was detected in 2 patients. In both cases, the thrombosis resolved within 1 month, confirmed by follow-up ultrasound scans. A lateral (tangential) fat injection method was shown to safely deposit fat above the gluteus maximus fascia.

Conclusions:

Ultrasound scans are highly accurate, noninvasive, and well-tolerated by patients. Some of these applications are likely to improve patient safety. Early detection of deep venous thromboses is possible. Unnecessary anticoagulation may be avoided. Subclinical abdominal defects may be detected. Ultrasound may be used in the office to evaluate breast implants, masses, and seromas. In surgery, this device confirms the level of buttock fat injection.

Gluteal Augmentation and Enhancement of the Female Silhouette: Analysis and Technique

Dr. Constantino Mendieta demonstrates and details his personal technique for gluteal augmentation. The video demonstration is divided into three parts: Part I, Aesthetic Analysis and Preoperative Marking; Part II, Creating the Female Silhouette with Circumferential Lipoplasty; and Part III, Autogenous Gluteal Augmentation. Artistic concepts for gluteal augmentation and contouring the female silhouette and technical considerations for patient safety are emphasized. This Master Series Video article is the first in a planned series of video vignettes.