Evaluation of postoperative complications of hypospadias using high-frequency ultrasound imaging.

PURPOSE: Various complications following hypospadias surgery present distinct manifestations when examined with ultrasound. Utilizing high-frequency ultrasound, clinicians can promptly identify these complications and initiate appropriate treatment. The aim of this study is to catalogue the ultrasonographic presentations of various postoperative complications following hypospadias surgery, thereby providing a reference for ultrasonographic diagnosis. METHODS: Ultrasonic images of post-hypospadias surgery from October 1, 2015, to June 30, 2023, recorded at the Plastic Surgery Hospital of the Chinese Academy of Medical Sciences, serve as the basis for this investigation. Drawing on patient clinical diagnoses, this study compiles and selects representative ultrasound images of diverse complications. RESULTS: The study encompassed a total of 121 subjects; 26 demonstrated urethral stricture on ultrasonic images, two presented local urethral dilation, six showed intraurethral hair-like structures, 17 revealed intraurethral septum, two exhibited intraurethral fold, one had urethral calculus, one displayed urethral calcification, 12 indicated intraurethral urine accumulation, and two showed urethral diverticulum. CONCLUSION: Ultrasound examination is helpful for postoperative diagnosis following hypospadias, detecting complications such as urethral stricture, urethral hair growth, and urethral diverticulum, which can help doctors choose appropriate clinical treatment strategies.

Three-point Method Nerve Block for Relieving Pain of Microbotox Injection in Middle and Upper Face.

Background: With the popularity of microbotox, pain caused by multiple microdroplets and subcutaneous injection of botulinum toxin is increasing. This study presents a new, refined, three-point nerve block technique that provides effective pain relief during minimally invasive injection therapy targeting the middle and upper face. Methods: Fifty volunteers underwent facial ultrasonography to measure the locations of the supraorbital and infraorbital foramen. Following microdrop Botox injection of the middle and upper face, 100 patients underwent a self-controlled study to analyze whether a three-point nerve block surpasses topical anesthesia for reducing injection pain. The visual analog scale pain score, the time of the three-point method and botulinum toxin injection, and side effects were recorded. Results: Among the volunteers, the location of the supraorbital and infraorbital foramen showed no statistical difference between the left and right sides. For the 100 patients (13 men, 87 women) who underwent the three-point nerve block, the visual analog scale pain scores on the experimental side were significantly lower than those on the control side, except in the frontotemporal region (2.46 ± 0.50, 2.42 ± 0.47, P > 0.05). The duration of the unilateral three-point nerve block was 74.8 ± 5.64 seconds. The total injection time was 189.86 ± 26.79 seconds (range 148-286 s). Conclusions: The three-point method exerted prominent analgesic effects during middle and upper facial treatments, with benefits including a precise block region, high satisfaction, and simple operation technique. Therefore, clinicians can easily master and apply this method.

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 .

Light-Activated BF3·Et2O-Promoted Generation of Singlet Oxygen and Cascade Reaction of Unsaturated Amides.

Herein, BF3·Et2O-promoted O-insertion/spirocyclization/fluorination/ring-expansion of unsaturated amides to synthesis of spiro[benzo[b]-[1,4]dioxepine-3,5'-oxazole] skeletons in the presence of natural light and O2 (3Σg-) was reported. Air was the oxygen source of the 1O2-generation and O-insertion reaction under metal-free and mild conditions. BF3·Et2O played multiple roles, such as Lewis acid, activating reagent, and fluorine source in the reported cascade. A mechanism involving 1O2 generation/activation of double bond/O-insertion/spirocyclization/fluorination/ring expansion was supposed.

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.

The Buried Guide Suture Method: A Novel Technique to Correct Traumatic Facial Dimples.

SUMMARY: Facial dimpling, frequently occurring after blunt trauma, presents as soft-tissue depression, which is particularly apparent during facial expression. The displacement of subcutaneous tissue can be detected and measured by high-frequency ultrasound. Limited surgical methods have been applied in these closed-injury cases. Repositioning the subcutaneous tissue without incisions on unscarred skin is challenging. The authors propose a novel three-dimensional technique to suture and fix the subcutaneous tissue at a distance through a concealed incision. The buried guide suture method was used in the treatment of 22 patients with traumatic facial dimples on the cheek. All patients showed great improvement in their depressed deformity with minor complications. This technique provides an option to correct soft-tissue depression without leaving a visible scar, especially for mimetic rupture caused by blunt trauma.

The Application of High-frequency Ultrasonic Imaging in Identifying Fillers in the Temporal Region.

Background: This study aimed to evaluate the ultrasonic manifestations of diversified corium fillers in the temporal region and to provide clinicians with suggestions for diagnosis and treatment. Methods: The facial ultrasound images of 116 patients, including 110 women and six men, 20-61years of age, were analyzed at the Chinese Academy Medical Sciences and Peking Union Medical College from November 2014 to November 2021. Results: We identified 48 cases of polyacrylamide, 31 cases of fat, 27 cases of hyaluronic acid, seven cases of hydroxyapatite, two cases of silicone oil, and one case of prosthesis. Polyacrylamide mainly showed irregular flocculent hypoechoic or fine punctate hypoechoic in ultrasound; it could be aggregated as a cystic hypoechoic area or diffused in the tissue space, and the probe could be pressurized to see the echo floating or dislocation flow. Fat mainly showed lobulated hypoechoic deposition with some hyperechoic linear intervals. Hyaluronic acid mainly showed an anechoic structure with a clear boundary, uniform internal echo, and no obvious blood flow signal. If diffused in the surrounding tissues, it was mainly characterized by anechoic or low-echo areas in the stratified tissues. Hydroxyapatite mainly showed strongly hyperechoic patch areas with posterior acoustic shadowing artifacts. Silicone oil was mostly found under the epidermis, showing a high echo in the form of clouds and causing unclear displays of deep tissue. Prosthesis showed hypoechoic prosthesis structure. Conclusion: High-frequency ultrasound had a certain significance in the identification of the fillers of the temporal region.

An Exploration of the Anatomy of the Forehead of Asians and Its Relationship With Forehead Lines Based on Ultrasound Imaging.

BACKGROUND: A profound understanding of the various frontal tissues' morphology and their relationship with forehead lines can efficiently guide clinical treatment. OBJECTIVES: The authors explored the relationship between frontal anatomy and frontal lines. METHODS: We measured the thickness and shape of tissues in different regions of the forehead of 241 Asians. Then, we analyzed the relationship between the types of frontalis muscle and frontal lines, as well as the relationship between the frontal anatomical structures and the production of frontal lines. RESULTS: We classified the types of frontalis muscle into 3 categories comprising 10 subtypes. The skin (0.78 mm vs 0.90 mm, P < .05), superficial subcutaneous tissue (0.66 mm vs 0.75 mm, P < .05), and frontalis muscle thickness (0.29 mm vs 0.37 mm, P < .05) of people with obvious dynamic forehead lines were significantly thicker than those of people without significant dynamic forehead lines. However, no significant difference in the deep subcutaneous tissue thickness was found between people with and without static forehead lines (1.36 mm vs 1.34 mm, P < .05). CONCLUSIONS: This study shows the relationship between the frontal structure and frontal lines. Therefore, these results can provide references for treating frontal lines, to a certain extent.

Different Performances of BF3, BCl3, and BBr3 in Hypervalent Iodine-Catalyzed Halogenations.

Herein, hypervalent iodine-catalyzed halogenation of aryl-activated alkenes using BX3 (X = Cl, Br) as the halogen source and activating reagents was reported. Various halogenated 1,3-oxazine/2-oxazoline derivatives were obtained in good-to-high yields. Using BF3 resulted in different substitute sites from BBr3 and BCl3 of the products, indicating different reactive intermediates and reaction pathways. The reaction underwent a "ligand coupling/oxidative addition/intermolecular nucleophilic attack/1,2-aryl migration/reductive elimination/intramolecular nucleophilic attack" cascade when BF3 was applied as the halogen source, while 1,2-aryl migration has "disappeared" when the halogen source was BBr3 or BCl3. Possible catalytic cycles were proposed, and DFT calculations were conducted to demonstrate the differences among BX3 (X = F, Cl, Br) in the hypervalent iodine-catalyzed halogenations.

Surgical Correction of the Deformity After Orbicularis Oculi Muscle Rupture: A Case Report.

Facial contusion may be accompanied by inconspicuous structural damage of the underlying muscular tissue, leading to unnatural expressions. Surgery can be a choice to correct this dynamic deformity. This case report describes a rare case of orbicularis oculi muscle rupture following blunt injury. Cosmetic improvement was achieved with the surgical restoration of the torn muscle. The etiology of this phenomenon is also discussed.

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 .

Catalytic Synthesis of 5-Fluoro-2-oxazolines: Using BF3·Et2O as the Fluorine Source and Activating Reagent.

Hypervalent iodine catalyst-catalyzed nucleophilic fluorination of unsaturated amides using BF3·Et2O as the fluorine source and activating reagent was reported. Various 5-fluoro-2-oxazoline derivatives were synthesized in good to excellent yields (up to 95% isolated yield) within 10 min. The process was efficient and metal-free under mild conditions. A mechanism involving a fluorination/1,2-aryl migration/cyclization cascade was proposed on the basis of previous work and experimental results.

High-Frequency Ultrasound of Facial Filler Materials in the Nasolabial Groove.

BACKGROUND: Various dermal fillers are often used for nasolabial groove filling. High-frequency ultrasonography might be a valuable tool for assessing facial filler materials. METHODS: The facial ultrasound images of plastic surgery hospital of the Chinese Academy of Medical Sciences from November 2014 to November 2021 were analyzed and judged. RESULTS: A total of 94 patients who underwent high-frequency ultrasound with a nasolabial groove filler were included in the study. Hyaluronic acid was detected in 35 cases, polyacrylamide in 34 cases, lipofilling in 10 cases, silicon oil in seven cases, calcium hydroxyapatite in six cases, and silicone implant in two cases. The ultrasonic performance of hyaluronic acid was divided into four types: aggregation, diffusion, mixed pattern, and associated infection; of polyacrylamide was divided into five types: aggregation and inclusion, aggregation and non-inclusion, diffusion, mixed pattern, and associated infection; and of lipofilling was divided into four types: aggregation, diffusion, fat liquefaction necrosis, and cystic change. Echo intensity, echo characteristics, boundary clarity, fluidity, and blood flow signals can be used as the basis for identifying filler materials. CONCLUSION: High-frequency ultrasound has an identification significance for the filling materials in the area of nasolabial groove. 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 .

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.

Visible-light-mediated catalyst-free synthesis of unnatural α-amino acids and peptide macrocycles.

The visible light induced, photocatalysts or photoabsorbing EDA complexes mediated cleavage of pyridinium C-N bond were reported in the past years. Here, we report an ionic compound promote homolytic cleavage of pyridinium C-N bond by exploiting the photonic energy from visible light. This finding is successfully applied in deaminative hydroalkylation of a series of alkenes including naturally occurring dehydroalanine, which provides an efficient way to prepare ß-alkyl substituted unnatural amino acids under mild and photocatalyst-free conditions. Importantly, by using this protocol, the deaminative cyclization of peptide backbone N-terminals is realized. Furthermore, the use of Et3N or PPh3 as reductants and H2O as hydrogen atom source is a practical advantage. We anticipate that our protocol will be useful in peptide synthesis and modern peptide drug discovery.

Visible Light Induced Cu-Catalyzed Asymmetric C(sp3)-H Alkylation.

The asymmetric functionalization of C-H is one of the most attractive strategies in asymmetric synthesis. In the past decades, catalytic enantioselective C(sp3)-H functionalization has been intensively studied and successfully applied in various asymmetric bond formations, whereas asymmetric C(sp3)-H alkylation was not well developed. Photoredox catalysis has recently emerged as an efficient way to synthesize organic compounds under mild conditions. Despite many photoinduced stereoselective reactions that have been achieved, the related enantioselective C(sp3)-C(sp3) coupling is challenging, especially of the photocatalytic asymmetric C(sp3)-H radical alkylation. Here, we report a visible light induced Cu catalyzed asymmetric sp3 C-H alkylation, which is effective for coupling with unbiased primary, secondary, and tertiary alkyl fragments in high enantioselectivities. This reaction would provide a new approach for the synthesis of important molecules such as unnatural α-amino acids and late-stage functionalization of bioactive compounds, and will be useful for modern peptide synthesis and drug discovery.

Visible-light promoted regioselective amination and alkylation of remote C(sp3)-H bonds.

The C-N cross coupling reaction has always been a fundamental task in organic synthesis. However, the direct use of N-H group of aryl amines to generate N-centered radicals which would couple with alkyl radicals to construct C-N bonds is still rare. Here we report a visible light-promoted C-N radical cross coupling for regioselective amination of remote C(sp3)-H bonds. Under visible light irradiation, the N-H groups of aryl amines are converted to N-centered radicals, and are then trapped by alkyl radicals, which are generated from Hofmann-Löffler-Freytag (HLF) type 1,5-hydrogen atom transfer (1,5-HAT). With the same strategy, the regioselective C(sp3)-C(sp3) cross coupling is also realized by using alkyl Hantzsch esters (or nitrile) as radical alkylation reagents. Notably, the α-C(sp3)-H of tertiary amines can be directly alkylated to form the C(sp3)-C(sp3) bonds via C(sp3)-H - C(sp3)-H cross coupling through the same photoredox pathway.

Cu-Catalyzed cyanoalkylation of electron-deficient alkenes with unactivated alkyl bromides.

We here report the photoinduced Cu-catalyzed cyanoalkylation of electron-deficient alkenes by using alkyl bromides as alkylation reagents. In the reactions, 1°, 2°, and 3° unactivated alkyl bromides with various sensitive functional groups were well tolerated with good yields. Notably, terminal and internal alkenes, as well as alkene-containing peptides, were all tolerated well.