Three-Dimensional Morphological Study on the Effectiveness of Expanded Polytetrafluoroethylene Prosthesis in the Paranasal Augmentation.

BACKGROUND: The paranasal depression is a common facial feature of Oriental populations. One of the most wildly used method to improve it was paranasal augmentation using expanded polytetrafluoroethylene (ePTFE). The effectiveness of it should be tested by three-dimensional morphological measurements. METHODS: Patients who underwent paranasal augmentation using ePTFE between January 2017 and December 2022 were recruited in the study. The preoperative and postoperative clinical variables and three-dimensional measurement of patients were also collected. The satisfaction outcome were assessed. RESULTS: By establishing a coordinate system based on the Frankfurt plane, 16 landmarks including nasal alar crest, subnasal point, upper lip, pogonion, glabella, sub-cheek, orbitale, tragion in left and right side of faces were marked. Five segments, 4 ratios, and 3 angles were measured based on it. The significant increase of segments, ratios, and angles indicated that paranasal augmentation could increase the protrusion of paranasal area, both in absolute value and relative proportion. The significant decrease of other data indicated that the protrusion difference between paranasal base and upper lip, forehead, and chin, respectively, were shortened after surgery. The average size of implant was 6.54 ± 1.02 mm, and the average increase of paranasal height was 4.38 ± 1.04 mm postoperatively. This indicates that two-thirds of its height will ultimately be reflected effectively in the sagittal elevation of the paranasal base. CONCLUSIONS: Paranasal augmentation using ePTFE could effectively increase paranasal height and improve subunits relationships, and the ePTFE prosthesis should be designed and carve considering the 1/3 loss of height after implantation. 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 .

Double Reinforcing Strategy with Perpendicular Plate of Ethmoid in Asian Secondary Unilateral Cleft Rhinoplasty: A Finite Element Analysis.

BACKGROUND: Deviation and asymmetry relapse after secondary unilateral cleft rhinoplasty with septal extension graft is a common yet serious problem especially among Asian patients. Therefore, finding an effective approach to reduce deformity relapse remains a great challenge to plastic surgeons. METHODS: In this study, authors established finite element models to simulate different nasal cartilage-corrected options and different reinforcing strategies in secondary unilateral cleft rhinoplasty. A load of 0.01N was given to the nasal tip to simulate the soft tissue pressure, while two loads of 0.5N were separately given to the anterior and posterior part of the septal extension graft to simulate the rhinoplasty condition. Maximum deformations were evaluated to make stability judgments. RESULTS: The maximum deformation of different cartilage correction models in ascending order was: UCL deformity with septum correction, normal nasal cartilage, UCL nasal deformity, and UCL nasal deformity with lower lateral cartilage correction. When applied L-strut reinforcement graft was harvested from the perpendicular plate of the ethmoid bone, the maximum deformation of the models decreased significantly, and strong fixation of the septum could further enhance this decreasing effect. CONCLUSIONS: Correcting the septum and lower lateral cartilage together could improve the structural stability and symmetry in secondary unilateral cleft rhinoplasty. To keep the corrected septum stable and thus reduce deformity relapse, reinforcing the L-strut with perpendicular plate of ethmoid graft while strongly anchoring the septal cartilage to the anterior nasal spine was proved to be effective in both finite element analysis and clinical observation. 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 .

M-Shaped Auricular Cartilage Grafts for Correcting Short Nose Deformity in Asians: A Retrospective Study.

BACKGROUND: The demand for rhinoplasty in Asia is growing annually, and short nose deformity has been one of the main reasons for the surgery due to its high incidence. There is an urgent need for rhinoplasty suitable for Asians because of their different facial features from Westerners. The M-shaped auricular cartilage rhinoplasty has been developed as a new method for correcting short nose deformity for Asians. This study aimed to evaluate the aesthetic and functional results of M-shaped auricular cartilage rhinoplasty compared to clinically commonly used rhinoplasty methods. METHODS: A total of 45 patients were enrolled and divided into three groups of 15 patients: The first group underwent M-shaped auricular cartilage rhinoplasty, the second group underwent auricular-septal cartilage rhinoplasty, and the third group underwent overlapped auricular cartilage rhinoplasty. All of these patients underwent comprehensive rhinoplasty and had silicone or expanded polytetrafluoroethylene implants in the dorsum of their noses. RESULTS: The patient score improvements on the three patient-reported outcome measures were higher in the M-shaped auricular cartilage rhinoplasty group (1.65/1.79/0.11) compared with the overlapped auricular cartilage rhinoplasty group (1.40/1.51/0.05), and the score improvements in the auricular-septal cartilage rhinoplasty group (2.04/1.98/0.28) were the highest. CONCLUSIONS: This is a retrospective clinical study demonstrating the clinical efficacy of M-shaped auricular cartilage rhinoplasty. Compared with the overlapped auricular cartilage rhinoplasty, the effect of this novel M-shaped method is better. However, when compared to the auricular-septal cartilage rhinoplasty with septal extension and reinforcement using nasal septal cartilage, its effect is slightly worse. 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 .

Correction of Short Nose Using M-shaped Cartilage in Asian Patients: Finite Element Analysis and Recommendations for Surgery.

BACKGROUND: Using M-shaped cartilage grafts is a new method for the correction of short nose deformity with good effect for Asians. Although the basic approach to M-shaped cartilage surgery is well understood, there is a great deal of uncertainty when plastic surgeons perform the procedure, and still a lack of standard guidance on the specific details. METHODS: In this study, the authors used finite element analysis to explore and compare postoperative cartilage stability of different fixing methods, different suturing positions, and different sizes of M-shaped cartilage. The authors applied a 0.01 N load to a 1 cm2 area of the nasal tip to simulate nasal tip palpation and compared the maximum deformations of different groups, which were used to make stability judgments. RESULTS: The maximum deformation of the model was the least when the M-shaped cartilage was fixed medially to the septal cartilage and laterally to the outer crura of the lower lateral cartilage. At the same time, the maximum deformation was the least when the M-shaped cartilage was sutured to the middle of the nasal septal cartilage. Besides, the length of M-shaped cartilage was preferably around 30 mm, while its width was not worthy of being overly concerned. CONCLUSIONS: For optimal postoperative stability of Asian short nose correction, the M-shaped cartilage should be sutured and fixed medially to the middle of the septal cartilage and laterally to the lateral crura of the lower lateral cartilage, and the length of the M-shaped cartilage should be controlled at around 30 mm. 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 .

Rhinoplasty with Simultaneous Autologous Full-Face Fat Transfer for Asian Facial Contouring Balance: A Retrospective Study.

BACKGROUND: The aesthetic facial contouring procedures have gained an increasing popularity in the Asian population. Nevertheless, currently, there are few specific literature assessments and studies on the outcomes of rhinoplasty combined with full-face fat graft contouring. To conduct an objective evaluation of the efficacy of Asian rhinoplasty combined with autologous facial fat transfer in terms of 3-dimensional measurement and patient-reported outcomes. METHODS: Patients who underwent rhinoplasty combined with full-face fat transfer for facial contouring between January 2016 and July 2019 were recruited in the study. The preoperative and postoperative clinical variables and 3-dimensional measurement of patients were also collected. The satisfaction outcome of surgeons and patients was assessed. RESULTS: Twenty patients completed rhinoplasty with full-face fat transfer. The average postoperative follow-up was 10.2 months (range 6-24 months). The nasal length, and the nasal protrusion rate were significantly increased (p < 0.05) after surgery, and the median number of nasolabial angles decreased from 106° to 101°, which was closer to the aesthetic standard of 90°-100°. The topographical projection images of whole face indicated that the volume of frontal, temporal, inner cheek and chin regions were increased obviously. All cases received satisfaction outcome based on surgeons' satisfaction scale, ROE scale, FACE-Q overall facial satisfaction scale, and FACE-Q Rhinoplasty scale. Additionally, no patients had intraoperative or postoperative complications. CONCLUSIONS: Rhinoplasty combined with full-face fat transfer is a reliable and effective method of augmenting and contouring the facial convexity in the Asian populations. 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 .

Organoids and Their Research Progress in Plastic and Reconstructive Surgery.

Organoids are 3D structures generated from stem cells. Their functions and physiological characteristics are similar to those of normal organs. They are used in disease mechanism research, new drug development, organ transplantation and other fields. In recent years, the application of 3D materials in plastic surgery for repairing injuries, filling, tissue reconstruction and regeneration has also been investigated. The PubMed/MEDLINE database was queried to search for animal and human studies published through July of 2022 with search terms related to Organoids, Plastic Surgery, Pluripotent Stem Cells, Bioscaffold, Skin Reconstruction, Bone and Cartilage Regeneration. This review presents stem cells, scaffold materials and methods for the construction of organoids for plastic surgery, and it summarizes their research progress in plastic surgery in recent years.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 .

Morphological Measurement of Asian Osteal Nasal Base for Paranasal Augmentation.

BACKGROUND: Paranasal augmentation has been a popular approach in restoring Asian patients' lateral profile. Irregular surface in the surgical area emphasizes the importance of morphological evidence for the preoperative evaluation and the design of paranasal implants. METHODS: We retrospectively collected craniofacial computer tomography scans of patients in the department of plastic surgery from 2020 to 2022. The imaging data were imported to Mimics (version 20.0; Materialize, Leuven, Belgium) for three-dimensional reconstruction. Measurements of osteal nasal base were performed in 3-matics (version 12.0; Materialize). The severity of paranasal concavity was graded by a senior doctor to study the correlation with measured variables. RESULTS: Fifty-seven patients with a median age of 27 years (IQR: 22-33) were included in the study. For design of paranasal implants, the lengths of both lower and lateral edge were measured for reference. In the regression analysis, the alar base-alveolar process angle was significantly associated with the degrees of paranasal concavity (OR = 1.222, p = 0.00001). CONCLUSIONS: Morphological data of osteal nasal base were measured and presented in the current study. The analysis supported that alar base-alveolar process angle be used for preoperative grading and evaluation to help guiding treatment decisions. 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 .

Autologous Shuffling Lipo-Aspirated Fat Combined Mechanical Stretch in Revision Rhinoplasty for Severe Contractures in Asian Patients.

BACKGROUND: A severely contracted nose is a common occurrence. Intraoperative expansion is not sufficient to soften the severely constricted nasal envelope, which poses challenges in revision rhinoplasty. In recent years, adjuvant therapies, including nasal fat grafting and cell component injection, are applied before revision rhinoplasty to soften the nasal envelope. Herein, autologous shuffling lipo-aspirated fat and manual mechanical stretch were combined as adjuvant therapy before revision rhinoplasty. METHODS: A total of 24 patients with severe nasal contracture were included in this study. Of these, 8 received autologous shuffling lipo-aspirated fat and manual mechanical stretch before revision rhinoplasty (comprehensive therapy), 8 underwent mechanical stretch and revision rhinoplasty, and 8 patients underwent only revision rhinoplasty. The objective and subjective outcome assessment was processed in the follow-up period of 6 months. Nasal length, nasal tip projection, nasofrontal angle, and nasolabial angle were measured, and potential complications were assessed. RESULTS: All 24 patients underwent a successful revision rhinoplasty. In the comprehensive therapy group, no patient had postoperative wound infection and defect of the nasal column mucous. The comprehensive treatment group had the most significant improvement in nasal length and nasal tip projection, and the nasolabial angle was the closest to 90°, which indicated the most effective nasal revision and aesthetic contour. CONCLUSIONS: The adjuvant therapy combines autologous shuffling lipo-aspirated fat and manual mechanical stretch before revision rhinoplasty could effectively improve the surgical outcome and decrease the postoperative complications regarding severe nasal contractures. 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 .

Subcutaneous Face and Neck Lift With Prefabricated Skin Excision: A Practical Technique With Favorable Results in Young and Middle-Aged Chinese Patients.

BACKGROUND: Subcutaneous face and neck lift is a popular procedure in Chinese face and neck rejuvenation. However, there are limited studies focusing on the details and evaluation of this technique. OBJECTIVE: To introduce our subcutaneous face and neck lift technique with prefabricated skin excision, evaluating the efficacy with patient reported FACE-Q Scale. In addition, to investigate on skin excision and patient's satisfaction under different circumstances. MATERIALS AND METHODS: One hundred forty-five consecutive patients were identified who underwent subcutaneous face and neck lift with our technique. Online FACE-Q Scale was assessed for patients' satisfaction 6 months postoperatively. The skin excision and FACE-Q Scale were compared among different subgroups. RESULTS: Fifty-eight patients completed the FACE-Q. Patients demonstrated high satisfaction overall and felt 8.8 years younger than their actual age. Intraoperative skin excision data verified the practicality of the prefabricated technique. There was a constant trend with patients' satisfaction among different age groups. The preliminary comparison between the facial bone reduction group and the general group revealed no significant difference. CONCLUSION: The subcutaneous face and neck lift technique with prefabricated skin excision is an effective technique with favorable results in young and middle-aged Chinese patients. LEVEL OF EVIDENCE: IV. Evidence obtained from a retrospective cohort analytic study.

Four cases of abdominal expander implantation in adult chronic osteomyelitis of lower extremity with soft tissue defect and literature review.

In this study, we intend to explore the clinical efficacy of abdominal expander implantation combined with flap technique in adult chronic osteomyelitis of lower limb with soft tissue defects, and to provide the basis for the promotion of the technique in clinical practice. Four patients diagnosed with chronic osteomyelitis of lower extremity with soft tissue defect were enrolled in this prospective study. Evaluation indicators included state of flap survival, state of abdominal incision, surrounding of abdominal wound scar, satisfaction of the patient, state of flap survival half a year after surgery, whether the 3D prosthesis is successfully implanted and limb movement. Four patients had complete flap survival, two of whom had a small amount of skin graft survival disorder in the vascular pedicle area, which improved after 1 month of dressing change. The expander had an average expansion time of 31.5 days, an average water injection of 525 mL, and an average skin volume taken of 159 cm2 . No incision exudation, incision dehiscence, subcutaneous exudate and other complications occurred. The mean Vancouver Scar Scale score at 3 months after surgery was 3.5 (range from 3 to 6) points. Four patients showed good flap survival at six-month follow-up. 3D printed prosthesis were all successfully implanted. The treatment of adult chronic osteomyelitis of lower extremities with lower abdominal implantable expander combined with flap technique can effectively increase the skin harvesting area, reduce the suture tension of abdominal skin harvesting area and the scar hyperplasia of abdominal skin harvesting area.

Island sternocleidomastoid myocutaneous flap for posterior pharyngeal wall defect repair after anterior cervical spine surgery.

Injuries and tumours of the cervical spine represent therapeutic challenges to the treating surgeon due to the complex anatomical relationships and biomechanical features. The anterior cervical midline (ACM) and anterior cervical retropharyngeal (ACR) approaches are effective and safe surgical approaches for certain cervical spine lesions, such as cervical spine neoplasms, atlantoaxial subluxation, and certain odontoid fractures. Posterior pharyngeal wall defects (PPWDs) is one of the most frequently encountered surgical morbidities after anterior cervical spine surgery (ACSS). However, limited information has been published concerning effective approaches for PPWD reconstruction after ACSS. The manuscript aimed to describe a novel application of the island sternocleidomastoid myocutaneous flap (ISMF) in the management of PPWDs after ACSS, including surgery with the ACM approach and ACR approach. From April 2015 to November 2019, the clinical data of three patients with PPWDs repaired using the ISMF in Peking university third hospital were retrospectively analysed. The observational indexes are as follows: postoperative survival of the flap, wound healing 2 weeks after surgery, eating and pronunciation function 2 months after surgery. The above indexes of these three cases recovered well. Three patients did not have any persistent PPWD after repair with the ISMF and did not require any further surgical procedures related to the cervical spine.

Clinical significance of the secondary pedicle amputation of the repair of distal defects with pedicled axial flap.

We aimed to explore the clinical significance of the secondary pedicle amputation of the repair of distal defects with pedicled axial flap. Five patients who underwent pedicled axial flap transfer to repair a large area of skin and soft tissue defects in our hospital were included in this retrospective study. Detailed information including general data and clinical data, such as preoperative complication, type of primary wound, the distance between the primary wound and the donor site (cm), postoperative complications, and types of axial flap were collected. The patients had good joint movement at 6 months after pedicle amputation. At 48 hours after transplantation, except for the last patient (NO.5), there were no obvious complications such as blood supply disorder, infection, and incision dehiscence of the patients, and the flaps survived well. Just after pedicle amputation, 3 and 6 months after pedicle amputation, the flaps survived well with good local morphology. Forty-eight hours after operation, part of the distal flap in the last patient (NO.5) was necrotic. After 6 months of pedicle amputation, part of the flap was transferred to the distal wound again. At 6 months after pedicle amputation, these patients could accept local scars even though the scar of the last patient was obvious. The secondary pedicle amputation of the repair of distal defects with axial flap could avoid the compression of the vascular pedicle in the subcutaneous tunnel between the donor site and the primary wound, which may ensure the bold supply and increase the survival rate of the flap.

Clinical study on orthopaedic treatment of chronic osteomyelitis with soft tissue defect in adults.

To investigate the clinical application value of different flap transfer and repair techniques in adult patients with chronic osteomyelitis of limbs complicated with soft tissue defects. According to the characteristics and defects of 21 cases, different plastic surgery was applied, including debridement, negative pressure device, and tissue flap to cover wound. Among 21 cases of chronic osteomyelitis complicated with local soft tissue defect, 15 patients were repaired with sural neurotrophic musculocutaneous flap transfer, 2 patients were repaired with medial plantar skin flap transfer, 2 patients were repaired with ilioinguinal skin flap transfer, 1 patient was repaired with z-forming wound, and 1 patient was repaired with soleus muscle flap combined with full-thickness skin graft. All the 21 patients underwent bone cement implantation after dead bone osteotomy. Among them, 19 patients underwent bone cement replacement with 3D prosthesis within 6 months to 1 year after surgery, and 2 patients carried bone cement for a long time. Early intervention, thorough debridement, removal of necrotic or infection, and then selecting the appropriate wound skin flap coverage are important means of guarantee slow osteomyelitis wound healing and for providing a possible way to permanent prosthesis implantation subsequently.

Subcutaneous Face and Neck lift: A Traditional Method With Definite Effects Among Asians.

BACKGROUND: The mainstream facelifts in Western countries always involve the superficial fascia/superficial musculoaponeurotic system treatment. Meanwhile, subcutaneous face and neck lifts are widely applied among Asians. OBJECTIVES: The authors sought to evaluate outcomes of subcutaneous face and neck lift, including patient-reported and 3-dimensional (3D) measurement outcomes, and report on details of surgical procedures. METHODS: Patients who received a subcutaneous face and neck lift from January 2017 to June 2019 were asked to complete FACE-Q scales, and facial information was collected by the Vectra 3D imaging system preoperatively and postoperatively. Volume changes in midface and possible displacement of facial landmarks were measured. The range of dissection and the amount of skin removed were recorded intraoperatively. RESULTS: In total, 119 patients (median age, 46 years, interquartile range, 40-53 years) received a subcutaneous face and neck lift. Among them, 88 patients completed pre- and postoperative FACE-Q scales. Patients' satisfaction with facial subunits improved and wrinkles were significantly relieved (P < 0.001). Nineteen patients (38 midface sides) completed 3D image data collection. Postoperatively, zygomatic volume increased, and nasolabial and lateral cheek volumes decreased (volume change of 2.2 ±â€…1.3 mL). Mouth, nose, and eye displacements were negligible postoperatively. The widths of skin removed at the middle temporal, front of the sideburns, upper helix, earlobe, and retro-auricular were 13.8 ±â€…1.9 mm, 19.6 ±â€…3.1 mm, 27.6 ±â€…3.9 mm, 16.4 ±â€…3.9 mm, and 32.2 ±â€…4.0 mm, respectively. CONCLUSIONS: The authors' subcutaneous face and neck lift was effective in relieving nasolabial sagging, improving wrinkles, and achieving facial rejuvenation.

The Z-plasty contributes to the coalescence of a chronic non-healing wound.

This study aimed to explore the treatment effect of Z-plasty on a non-healing wound. A total of 72 patients diagnosed with a chronic non-healing wound in Peking University Third Hospital from November 2009 to August 2019 were retrospectively analysed. Among them, 27 patients were treated with Z-plasty, and 45 patients were treated with the general method. Detailed patient information was retrieved from medical records, including age, gender, body mass index (BMI), alcohol, smoking, and comorbidities (diabetes mellitus, hypertension, heart disease). Surgical parameters included operation time and intraoperative blood loss. Wound swelling, epidermal blisters, wound edge colour, and skin temperature at 1 day after surgery were assessed to evaluate the blood supply of the wound. Surgical complications included infection, haematoma, dehiscence, and non-healing within 2 weeks postoperatively. Student t test (for continuous data) and Chi-square test (for categorical data) were conducted to determine the statistical difference. We found no significant differences in age, gender, BMI, alcohol, smoking, and comorbidities between the two groups. Z-plasty did not show any advantages in the surgical time, invasive blood loss, hospital days, and hospitalisation expenses. The incidence of abnormal wound edge colour with Z-plasty was significantly lower than that with the general treatment (P < .05), and the Z-plasty enables better healing of the patient's wound (P < .05). Z-plasty promoted better recovery of chronic non-healing wounds than direct suturing.

A Novel Endoscopic Forehead Lift Technique for Patients with Upper Facial Wrinkles: Morphometric Evaluation and Patient-Reported Outcome using FACE-Q Scales.

Chinese patients more frequently complain of forehead wrinkles than eyebrow and upper eyelid ptosis. Besides the commonly used brow-lifting technique, a novel technique to satisfy the demands of Chinese patients is needed. In this article, we introduce our novel endoscopic forehead lift procedure and analyze the morphometric evaluation and patient-reported outcomes. From January 2010 to January 2017, 171 Chinese patients underwent endoscopic forehead lift in which two parallel incisions were made on the frontalis muscle to relieve forehead wrinkles. Biopsy forceps were used to bite off the glabella muscles to relieve wrinkles between the eyebrows. Lifting devices were not used. Morphometric evaluations of eyebrow locations were performed, and the vertical distance of the upper eyebrows was measured post- and preoperatively to evaluate the elevation range. FACE-Q scales were sent to patients who were still being followed-up. A total of 46 patients underwent the morphometric evaluation, which suggested that the eyebrows were elevated effectively. At 12 to 36 months postoperatively, the median post-/preoperative ratio was 118.4, 112.5, and 111.8% in the medial, middle, and lateral eyebrows, respectively. In the same patients, at 37 to 84 months postoperatively, the median post-/preoperative ratio was 116.6, 112.2, and 108.9% in the medial, middle, and lateral eyebrows, respectively. Sixty-five patients completed the FACE-Q scales, demonstrating high satisfaction levels with the forehead and eyebrow, outcome, and decisions, with a median score of 100 for each. Postoperative appraisal revealed that the lines in the forehead and between the eyebrows had a good outcome with scores of 86 and 93, respectively. The median number of years younger that patients thought they appeared was 7. The most frequent self-claimed recovery symptom was temporary forehead skin numbness (83.1%) followed by a receding hairline (46.2%). Our endoscopic forehead lift procedure was effective in relieving forehead and glabella wrinkles and lifting the eyebrows. This was a level of evidence III study.

Morphological Classification of the Zygomatic Regions in Young Chinese Han Males and Females Based on a Simulated Moiré Pattern.

The complex curved contours of the zygomatic regions are difficult to analyze. Therefore, a better evaluation medium must be developed. We aimed to examine and summarize the morphological characteristics of the zygomatic region by using a moiré pattern map and computer algorithm. In this cross-sectional study, we collected three-dimensional images of the facial contours of 251 Han Chinese youth and established a morphological moiré map database. Clustering analysis using a computer algorithm was applied to obtain the zygomatic morphologies for classification. Aesthetic evaluation was performed to summarize the characteristics of the zygomatic types and provide reference for the preoperative morphological design of the midface. Zygomatic regions were morphologically classified into five types. Each type had its typical feature in the moiré pattern map. The moiré stripes in the left zygomatic region formed an "Ω" shape outward and downward in type 1, and they tended to be diagonal like "\\\" in type 2, smoothly curved like ")))" in type 3, vertical like "|||" in type 4, and diagonal like "///" in type 5. The aesthetic evaluation outcome indicated that the integrally flat zygoma (type 4) was more aesthetically pleasing among males, and the integrally prominent zygoma (type 3) was more aesthetically pleasing among females. Five morphological contour types of the zygoma were classified among the Chinese Han males and females based on the simulated moiré pattern. This morphological classification would aid in preparing a guide for clinical diagnosis and surgical planning.

Risk Comparison of Filler Embolism Between Polymethyl Methacrylate (PMMA) and Hyaluronic Acid (HA).

BACKGROUND: The incidence of vascular complications varies among different fillers. The main purpose of this study was to compare the risk of embolism between PMMA (Artecoll) and hyaluronic acid (HA, Restylane) after artery injection. METHODS: Rabbit ears were injected via the central artery with 0.1 ml PMMA (group A), 0.1 ml HA (group B), 0.2 ml PMMA (group C), or 0.2 mL HA (group D), respectively. The formation of transparent emboli was monitored right after injection. Tissue necrosis and histopathological changes were analyzed on day 7. RESULTS: With 0.1 ml injected volume, PMMA was dispersed within a few minutes and only 5% of the injected ears had mild necrosis on day 7, while HA tended to form obvious transparent emboli, an indication of blood vessel clotting, and 60% of injected ears showed necrosis on day 7. With 0.2 ml injected volume, PMMA had a risk of complete blood vessel clotting in between 0.1 ml PMMA group and 0.1 ml HA group, and 30% of injected ears had necrosis; in contrast, 100% of 0.2 ml HA-injected ears showed transparent emboli and necrosis. The necrosis areas were significantly increased in the HA groups compared with PMMA groups at the same injection volumes. HA injection also caused dilation of small blood vessels. CONCLUSION: At the same injection volume, PMMA had less risk of embolism compared with HA. With increased injection volume, there were increased risks of embolism and necrosis for both PMMA and HA. NO LEVEL ASSIGNED: 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 .