A Method of Tumescent Anesthesia Based on Facial and Cervical Nerve Block for Face and Neck Liposuction.

OBJECTIVE: Liposuction of the face and neck is a common treatment for fat deposition. If conventional methods are used for tumescent anesthesia, patients will experience pain, affecting their surgery experience. Using general anesthesia for liposuction of the face and neck can increase the cost to the patient and cause various adverse effects. METHODS: The authors selected appropriate parts of the patient's neck, angle of the mandible, and face as needle entry points, and performed nerve block in different directions. Afterward, we performed facial liposuction on these patients and evaluated their level of pain. RESULTS: This study included a total of 20 female participants who underwent facial liposuction after a nerve block. The Visual Analog Scale score of the 20 participants was 0.55 (±0.60). There were no significant adverse reactions during the treatment process, and all patients expressed satisfaction with this treatment. CONCLUSIONS: In this article, the authors present a method of tumescent anesthesia based on facial and cervical nerve block that significantly reduces the pain associated with facial and neck liposuction, eliminating the need for general anesthesia and enhancing the patient's comfort during the procedure.

Application of High-Frequency Ultrasound to Evaluate Forehead Filling Materials.

BACKGROUND: In recent years, soft tissue materials have been applied as forehead fillers. Some filling materials need to be removed or refilled in a timely manner in certain situations; therefore, it is important to develop a method to identify the location and type of filling materials. This study summarizes the imaging findings of different filling materials under high-frequency ultrasound, providing a reference for clinical treatment. METHODS: We screened facial ultrasound images performed at the Plastic Surgery Hospital of the Chinese Academy of Medical Sciences from April 2015 to July 2023 and classified and summarized the types of frontal filling materials and their imaging results. RESULTS: This study included ultrasound imaging results from 114 patients, including 39 with hyaluronic acid (HA) filling, 45 with polyacrylamide hydrogel (PAG) filling, 14 who received autologous fat transplantation, 2 who received prosthesis implantation, 2 who received both HA and PAG filling, and 12 who received silicone oil filling. HA mainly manifests as an anechoic zone on ultrasonography, with images divisible into four types. PAG primarily presents as fine punctate echoes, divisible into five types. Fat transplantation presents as a low-echo area with uneven density, divisible into five types. Finally, the silicone oil-filling material appears as a cloud-like high echo on the forehead, visible throughout the entire skin layer, and unclear imaging in deep tissues. CONCLUSION: High-frequency ultrasound is a safe and reliable method to evaluate the type and position of forehead filling materials, which can be easily applied in clinical practice. LEVEL OF EVIDENCE IV: 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 .

Factors Influencing Bone Resorption after Augmentation Mentoplasty with Implants: A Retrospective Study Using Three-Dimensional Imaging.

BACKGROUND: Augmentation mentoplasty with implants is an extremely rewarding procedure. Bone resorption is almost unavoidable. The high-risk factors for chin bone resorption have not been explored in the past. This study aimed to analyze and evaluate the factors influencing bone resorption after augmentation mentoplasty with implants using three-dimensional imaging. METHODS: We retrospectively analyzed preoperative craniofacial Computed Tomography scan data from 105 patients who underwent mandibular implantation surgery and 108 patients who did not. We also examined the extent to which different factors influenced the occurrence of bone resorption in the chin area. RESULTS: Patients with silicone gel implants are more prone to bone resorption than those with Medpor implants. Patients who experienced bone resorption had thicker mentalis muscles than those who did not experience bone resorption (6.35 ± 1. mm vs. 5.73 ± 1.25 mm, P < 0.05), and thinner cortical bone (3.25 ± 1.65 mm vs. 5.22 ± 2.04 mm, P < 0.05). Additionally, implants placed above the mandibular bone were more likely to induce bone resorption than those placed below it. CONCLUSIONS: This study is the first to systematically reveal the impact of implant type, placement position, mentalis muscle thickness, and cortical bone thickness on bone resorption after chin augmentation surgery. For patients with thicker mentalis muscles and thinner cortical bones, greater attention should be paid to the occurrence of bone resorption. Choosing silicone implants or placing the implants higher on the mandible can help reduce the occurrence of bone resorption. This study can assist clinicians in selecting appropriate treatment methods, thereby reducing post-implantation bone resorption. LEVEL OF EVIDENCE III: 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.

Botulinum Toxin Injection Technique for Reducing the Masseter Size and Enhancing the Jawline.

BACKGROUND: The injection of botulinum toxin into the masseter muscle is an important method for improving hypertrophy. However, some patients may experience adverse reactions, such as sagging of the lower jaw. Therefore, we proposed a method of injecting botulinum toxin into the masseter and platysma muscles that would reduce masseter size and enhance the jawline. OBJECTIVES: The aim of this study was to reduce the masseter size while enhancing the jawline. METHODS: Twenty patients received botulinum toxin injections into the masseter and platysma muscles. Pain levels were evaluated with the visual analog scale. All patients were photographed before and 6 months after treatment. Evaluations were performed based on standardized criteria. The lift index, reduction index, and symmetry index were performed to assess the degree of jawline elevation, masseter size reduction, and jawline symmetry before and after treatment. RESULTS: The mean visual analog scale score of the 20 patients was 2.80 (±1.24). The mean lift index score decreased from 4.93 (±0.34) to 4.53 (±0.37), P < .05. The mean reduction index score decreased from 3.13 (±0.27) to 2.74 (±0.27), P < .05. The mean symmetry index score changed from 0.0393 (±0.0296) to 0.0257 (±0.0246), P < .05. CONCLUSIONS: Botulinum toxin injections into the masseter and platysma muscles through nerve block reduced the masseter size, elevated the jawline, and improved symmetry.

Localization of the Submandibular Glands Using High-Frequency Ultrasound.

BACKGROUND: Injecting botulinum toxin (BTX) into the submandibular glands (SMGs) can treat drooling symptoms in neurological diseases and improve the aesthetics of SMG hypertrophy and ptotic SMGs. OBJECTIVES: This study aimed to define the size and position of the SMGs by high-frequency ultrasound, and to perform statistical analysis to improve the safety and accuracy of BTX injection therapy. METHODS: Neck ultrasonography with high-frequency ultrasound was performed on 214 volunteers. The length, height, and thickness of the SMGs, and the distance between the SMGs and the midline, the anterior border of the sternocleidomastoid, the mandible, and the surface were measured. RESULTS: The SMGs were almond-shaped with a mean [standard deviation] length of 33.7 [4.7] mm, a thickness of 13.3 [2.9] mm, and a height of 27.6 [6.0] mm. The length and height were significantly different between underage and youth groups. The size of the SMGs did not show any notable differences with increasing BMI; however, their depth, and the distance from the mandible, midline, and anterior border of the sternocleidomastoid increased. No significant differences were observed between the affected and healthy sides in patients with microtia, hemifacial microsomia, or cleft lip and palate. CONCLUSIONS: Ultrasound provides more comprehensive information regarding the size and position of the SMGs, which can serve as a reference in BTX therapy and in the diagnosis of SMG diseases involving size alterations.

High-Frequency Ultrasound Imaging Findings of Different Mental Injectable Soft Tissue Fillers.

BACKGROUND: In recent years, the use of mental injectable soft tissue fillers is popular. However, some fillers are difficult to distinguish from pathological tissue, and some non-absorbable fillers need to be removed in time. Therefore, identification of different fillers is important. In this study, we summarized the ultrasonic manifestations of different mental injectable soft tissue fillers to provide references for clinical practice. METHODS: We screened the mental ultrasound images from November 2014 to November 2021 in the Plastic Surgery Hospital of Chinese Academy of Medical Sciences, identified different filling injection materials, and summarized and classified the ultrasonic characteristics of each filling material. RESULTS: A total of 244 cases were included, involving 62 cases of hyaluronic acid, 126 cases of polyacrylamide hydrogel, 19 cases of growth factor, 16 cases of calcium hydroxyapatite, 15 cases of silicone oil and 6 cases of fat. The ultrasonic manifestation of hyaluronic acid was anechoic area, which could be divided into six types according to the distribution characteristics. The ultrasonography of polyacrylamide hydrogel showed fine punctate echo, which could be divided into nine types. The ultrasonographic appearance of growth factor was similar to the echo of the surrounding tissue, and the boundary was not clear. Calcium hydroxyapatite was characterized by uneven hyperechoic area, which was spread in the tissue space, with unclear boundary with surrounding tissues. Sonographic patterns of silicone oil were hyperechoic and cloudy on high-frequency ultrasound. The deep tissue and periosteum layer were not clear. Transplanted fat showed isoechoic area or uneven low-echo area, with clear boundary and peripheral adipose tissue acoustic enhancement. CONCLUSIONS: High-frequency ultrasound is safe and reliable for identification and typing of chin filling injection materials, which can be applied in clinical practice. LEVEL OF EVIDENCE IV: 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 .

Evaluation of the effect of chin prosthesis implantation on mentalis muscles based on three-dimensional imaging technology.

BACKGROUND: Chin prosthesis implantation, a cosmetic procedure to correct chin asymmetry, depression, or retraction, is generally safe and simple. However, its long-term effects on surrounding tissues are a concern. This study aimed to use three-dimensional (3D) scanning to classify the mentalis muscle shapes and assess the impact of prosthesis implantation on these muscles. METHOD: This study evaluated 450 eligible female participants. Using three-dimensional imaging, data on the types, thickness, width, and length of the left and right mentalis muscles were collected and summarized. The impact of chin prosthesis on these muscle dimensions was assessed using analysis of variance, and the effect on muscle type was determined using χ2 test. RESULTS: Chin implant placement affected the mentalis muscles, resulting in increased length, thickness, and width. The subjects' mentalis muscles were categorized into 3 types and divided into 7 subtypes. χ2 test results indicated that implantation influences the classification of these muscles. CONCLUSION: Recognizing how implant placement affects the mentalis muscle can guide the development of treatments to mitigate these changes. Additionally, understanding the muscle's morphology enables more precise treatment approaches for patients.

Analysis of pathogen distribution and antimicrobial resistance at infected sites in plastic surgery.

OBJECTIVE: By analyzing the distribution and drug resistance of common pathogen in different sites in plastic surgery to provide reference for clinicians to choose the best antibacterial treatment plan. METHODS: Pathogens of postoperative infection in plastic surgery from January 2011 to December 2021 were retrospectively analyzed to determine the species and quantity, and to access the trend of each pathogen's detection rate. The antibiotic sensitivity and distribution characteristics of common pathogens were studied in conjunction with the site of infection. RESULTS: A total of 1709 bacterial strains were detected, including 1244 gram-positive bacterial strains and 465 gram-negative bacterial strains. The main pathogen of perineum was Escherichia coli (E. coli) and Pseudomonas aeruginosa (P. aeruginosa), while Staphylococcus aureus (S. aureus) was the most common pathogen in the other infected sites. The detection rate of methicillin-resistant S. aureus (MRSA) and methicillin-resistant coagulase-negative staphylococcus (MRCNS) was on the rise from 2011 to 2021. No S. aureus and coagulase-negative staphylococcus (CoNS) strains were resistant to vancomycin. The sensitive rate of S. aureus from all parts and CoNS from all sites except lower limbs and mandible was higher than 80% to linezolid. The resistance rate of S. aureus and CoNS in all parts to penicillin, clindamycin, and erythromycin was high. The susceptibility rate of CoNS in lower mandible was high to gentamicin. CONCLUSIONS: Staphylococcus aureus was the primary pathogen of gram-positive bacteria in all site of plastic surgery except perineum, followed by CoNS. The distribution and drug resistance of pathogen in different infection sites were different. We should formulate more accurate and reasonable antibacterial programs according to drug resistance results of various parts to reduce the emergence of resistant strains and effectively prevent and control infection.

Application of high-frequency ultrasound in detection and identification of nasal filling injection materials.

OBJECTIVE: To access and determine the ultrasound images of different nasal filling injection materials. METHODS: From November 2014 to November 2021, facial ultrasound images of Plastic Surgery Hospital of Chinese Academy of Medical Science were analyzed and judged. RESULTS: A total of 337 cases were enrolled, including 203 cases of hyaluronic acid, 102 cases of polyacrylamide hydrogel, 16 cases of calcium hydroxyapatite-based fillers, 10 cases of silicone oil, and 6 cases of growth factor. According to ultrasound images, hyaluronic acid is characterized by anechoic area with a clear boundary, which seems like a capsule, and the internal echo is uniform, there is no obvious blood flow signal in it. It is possible to see a stratified appearance if hyaluronic acid diffused into surrounding tissues, and it is mainly exhibited as hypoechoic area, with anechoic or hypoechoic areas in it. Polyacrylamide hydrogel showed irregular flocculent hypoechoic or fine punctured hypoechoic under ultrasound, which could aggregate into cystic hypoechoic area or disperse in tissue space, and echo floating or dislocation flow could be seen under probe pressure. Under ultrasound, calcium hydroxyapatite-based filler is characterized by heterogeneous hyperechoic or hypoechoic area, which spreads in the tissue space with unclear boundary with surrounding tissue, and no obvious liquid flow could be observed. Silicone oil is commonly found in the dermis, it is characterized by cloud-like high echo, the deep tissue is not clear. Growth factor is characterized by heterogeneous echo, which is similar to the echo of peripheral tissue, and the boundary is not clear. Plenty of blood flow signals suggest infection. If the image is characterized with posterior echogenic shadow, it suggests calcification. CONCLUSIONS: High-frequency ultrasound can identify the types of nasal filling injection materials and can guide the selection of clinical treatment plan according to the classification of imaging features.