Comparison of biopolymer scaffolds for the fabrication of skin substitutes in a porcine wound model

This study compared three acellular scaffolds as templates for the fabrication of skin substitutes. A collagen-glycosaminoglycan (C-GAG), a biodegradable polyurethane foam (PUR) and a hybrid combination (PUR/C-GAG) were investigated. Scaffolds were prepared for cell inoculation. Fibroblasts and keratinocytes were serially inoculated onto the scaffolds and co-cultured for 14 days before transplantation. Three pigs each received four full-thickness 8 cm × 8 cm surgical wounds, into which a biodegradable temporising matrix (BTM) was implanted. Surface seals were removed after integration (28 days), and three laboratory-generated skin analogues and a control split-thickness skin graft (STSG) were applied for 16 weeks. Punch biopsies confirmed engraftment and re-epithelialisation. Biophysical wound parameters were also measured and analysed. All wounds showed greater than 80% epithelialisation by day 14 post-transplantation. The control STSG displayed 44% contraction over the 16 weeks, and the test scaffolds, C-GAG 64%, Hybrid 66.7% and PUR 67.8%. Immunohistochemistry confirmed positive epidermal keratins and basement membrane components (Integrin alpha-6, collagens IV and VII). Collagen deposition and fibre organisation indicated the degree of fibrosis and scar produced for each graft. All scaffold substitutes re-epithelialised by 4 weeks. The percentage of original wound area for the Hybrid and PUR was significantly different than the STSG and C-GAG, indicating the importance of scaffold retainment within the first 3 months post-transplant. The PUR/C-GAG scaffolds reduced the polymer pore size, assisting cell retention and reducing the contraction of in vitro collagen. Further investigation is required to ensure reproducibility and scale-up feasibility.     

Management of the Long Nose: Review of Techniques for Nasal Tip Supporting Structures

The long nose with a “plunging” tip is a deformity that involves an inferiorly rotated nasal tip, leading to an increase in the length of the nose. The anatomic basis of the long nose with a plunging tip may be divided into two types. Type 1 presents a normal alar–cartilage complex inferiorly displaced by a long nasal septum and long upper lateral cartilages. Type 2 is caused by a dislocation of the alar cartilages downward from the aponeurotic attachments to the septal angle. During the study period, the authors identified 60 patients with long noses and plunging tips. For 22 patients with type 1 long noses, the high septal incision technique was used in 12 cases and the step technique in 10 cases. The invagination procedure alone was used for 22 of 38 patients with type 2 plunging noses. Also, an extension graft with the invagination procedure was used for 6 patients, and a columellar strut graft was used for 10 patients. A high septal incision increased tip rotation without significantly changing the amount of tip projection. However, the step procedure, the invagination technique alone, septal extension graft with the invagination technique, and columellar strut grafts increased nasal tip rotation and projection. During the study period, 38 patients were identified as having a smiling deformity, which was improved using the authors’ modification procedure. On the basis of the results, the authors recommend that the appropriate treatment for each patient with a long nose and a plunging tip must be determined by preoperative and intraoperative examination findings with the patient at rest and while smiling.     

自体耳软骨+鼻假体行短鼻延长鼻尖整形的影响

目的 评价在短鼻患者的延长鼻尖整形手术中鼻假体+自体耳软骨的应用效果。方法 选择西安美莱医学美容医院2017年4月-2020年3月短鼻延长鼻尖整形患者80例,采用随机数字表法分成A组和B组,各40例。A组使用鼻假体,B组使用鼻假体和自体耳软骨,比较两组手术成功率、切口愈合时间、满意度、并发症。结果 A组手术成功率、总满意度低于B组（P＜0.05）;A组切口愈合时间长于B组（P＜0.05）;A组并发症总发生率高于B组（P＜0.05）。结论 短鼻患者延长鼻尖整形术中应用自体耳软骨+鼻假体可提高手术成功率、缩短切口愈合时间、减少并发症发生,而且还会提高患者对于整形手术的满意度。     

Secondary Rhinoplasty of the Asian Nose: Correction of the Contracted Nose

The contracted nose is a unique entity that follows primary rhinoplasty in the Asian patient. The proposed reasons for this complication are capsular contraction from a silicone nasal implant, pressure necrosis of the lower lateral cartilage resulting from the nasal implant, and infection after alloplastic implantation. The two principal anatomic constituents that must be addressed at the time of secondary rhinoplasty are the lower lateral cartilages and the skin envelope. The lower lateral cartilages should be derotated, projected, and transfixed with an extended spreader graft. Additional onlay grafting may be required to provide greater nasal tip derotation and projection. A transcolumellar incision situated at the columellar-labial angle permits undermining of the upper lip skin to release tension on the incision. If the nasal tip retraction is severe, then the skin envelope may be insufficient to provide coverage to the new cartilaginous framework. In this case, a paramedian forehead flap is recommended to provide adequate tissue coverage. Correction of alar–columellar disparity should be undertaken with composite grafting only after 6 months have transpired to gauge the ultimate relation between the alae and columella. Infection that arises after correction of the contracted nose can be devastating. It should be treated aggressively, but tailored to the severity of the infection. Wound tension along the columella may predispose to skin necrosis and consequent cartilage exposure, which should be managed in turn with prostaglandin emollients to accelerate wound healing and to prevent infection.     

Differential expression of matrix metalloproteinase-1 in vitro corresponds to tissue morphogenesis and quality assurance of cultured skin substitutes

OBJECTIVE: To determine if matrix metalloproteinase-1 (MMP-1) was involved in the premature degradation of the dermal component in cultured skin substitutes (CSS) prepared with cells from burn patients. METHODS AND RESULTS: CSS 645 and 647 were prepared from clinical human fibroblasts (HF) and keratinocytes (HK) that demonstrated premature degradation of collagen-glycosaminoglycan sponges in vitro. The control CSS were prepared from clinical HF and HK, CSS 648, and a pre-clinical cell strain, CSS 644 that did not degrade the sponges. Surface electrical capacitance measures surface hydration and was significantly higher for CSS 647 from days 9 through 14. MTT (3-[4,5-dimethylthiazol-2-yl]- diphenyltetrazolium bromide) conversion, an indicator of cellular viability was significantly lower for the 6-mm punch biopsies from CSS 645 and 647 at day 15 as compared to control CSS. MMP-1 protein levels measured by ELISA were significantly higher in medium from HF 645 and 647 than controls on the day of CSS inoculation. At day 14 of incubation, the mean MMP-1 concentration was significantly elevated in the medium from CSS 645 and 647 versus the controls, CSS 644 and 648. Western blots, and casein zymography demonstrated the presence of the latent and active forms of MMP-1 in the HF and CSS media, respectively. CONCLUSION: MMP-1 was significantly higher in the media from two of the four HF strains and CSS after a 24 h incubation period. Elevated MMP-1 coincided with premature degradation of the dermal substitute in vitro, and reduced numbers of CSS that met quality assurance standards for clinical transplantation.     

Combination of a new composite biocampatible skin graft on the neodermis of artificial skin in an animal model

Introduction: There have been very limited and inconsistent attempts at combining the cultured epidermal autograft (CEA) with the neodermis of artificial skin (Integra). The reasons for this remain unknown. The basement membrane proteins of conventional CEA sheets are easily damaged by the dispase treatment during the harvesting of the CEA from the culture flask. The damage of the basement membrane proteins may affect the anchorage of CEA onto the neodermis of Integra. A new Composite Biocompatible Skin Graft (CBSG) was recently developed. Methods: Composite biocompatible skin graft consists of autologous keratinocytes cultivated on a pliable hyaluronate‐derived membrane (Laserskin) which has been pre‐seeded with allogenic dermal fibroblasts. Basement membrane proteins of CBSG are protected from the dispase treatment because the keratinocytes are directly seeded onto Laserskin. The engraftment of CBSG was evaluated on 20 wounds of 10 rats. Integra was grafted on two freshly excised full‐thickness wounds (3 cm in diameter) in the dorsum of each animal. A polypropylene ring was applied to each wound to prevent the migration of epithelium from the edges. Composite Biocompatible Skin Graft was used to cover the neodermis of Integra after the silicone membrane was removed 14?21 days postgrafting. Results: Fourteen (70%) of 20 skin biopsies taken at day 21 from the centre of the grafted wounds revealed regenerated epithelium. Conclusion: A feasible delivery system of cultured keratinocytes onto the neodermis of Integra is demonstrated in this animal ­experiment.     

鼻尖突出不足合并鼻指数过大的鼻型特点及联合治疗

目的 应用人体测量学以比例关系描述特定鼻型,探讨鼻尖突出不足合并鼻指数过大的鼻型特点及治疗方法,为鼻整形定量研究提供思路.方法 2010年3月至2011年10月,测量27例鼻尖低平、鼻翼肥大的青年女性鼻形态并计算指数值.患者均行隆鼻、鼻尖抬高并前延、鼻翼缩小三项鼻整形术.结果 随访3～12个月,效果满意.术后鼻指数、鼻宽深指数、鼻尖突出度均在正常范围内,其中部分患者比例值达到美学范围.结论 外鼻形态测量比例值能较客观、准确地描述某种鼻型.我国汉族青年女性,鼻指数大于82.05％,鼻尖突出度小于37.50％,可归类为鼻尖突出不足合并鼻指数过大鼻型,此类鼻型应用三项手术综合治疗,协调各亚单位比例,可塑造和谐美观的鼻型.     

Endoscopic-Assisted Correction of the Deviated Nose

The approach to nasal bone classic corrective rhinoplasty is an almost-blind technique, where the results depends on feeling by the surgeon's hand. To overcome these drawbacks, endoscopic-assisted corrective rhinoplasty and septoplasty were performed for 16 cases of deviated noses between January 1995 and May 1997. The average follow-up period was 18 months. All patients were evaluated by symmetrical nasal pyramid, recurrence of the bony deflection, and septal deviation. The postoperative courses were satisfactory in most cases, with few complications. Compared with 28 cases of classic rhinoplasty, the patient satisfaction rate was high (87.5% in endoscopic-assisted rhinoplasty, 71.4% in classic rhinoplasty), and the complication and revision rate was low (0% in endoscopic assisted rhinoplasty, 14.3 and 7.1% in classic rhinoplasty). But extra time (about 40 min) and greater expense were required for endoscopic-assisted rhinoplasty. It appeared to us that endoscopic control during corrective rhinoplasty and septoplasty is a big step toward obtaining better results in bony and cartilage resection with extreme precision under monitor control and magnification. This technique is not an open approach but permits one to see more of the nasal skeleton and bony septum, the cause of the deformity, and the immediate effect of the corrective measures used. The use of an endoscope in corrective rhinoplasty for deviated noses provides an expanded field of vision, direct manipulation of lesions, and better aesthetic and functional results.     

鼻内镜下鼻整形术同期鼻中隔偏曲畸形矫正

目的探讨鼻内镜下同期矫治鼻畸形及鼻中隔偏曲的手术方法与效果。方法鼻内镜下采用Killian切口和与其相连的大翼软骨间切口,显露畸形鼻骨结构及鼻中隔偏曲部位,松解牵拉力量,鼻中隔成形术消除鼻中隔畸形,截骨及复位鼻骨,使其解剖复位,重塑鼻支架。结果本组27例,均获满意效果,无复发和并发症。结论本方法可同时矫正鼻中隔及外鼻畸形,消除致畸原因,重塑外鼻支架,达到了恢复鼻腔通气功能与外鼻美容的双重效果。     

Nasal sarcoidosis : A cosmetic problem

Summary The literature relating to nasal sarcoidosis is reviewed and a case report about a patient with a gross nasal deformity due to sarcoidosis is presented.     

Technique of split skin graft fixation using hypafix: a 15-year review

The technique of graft fixation with Hypafix was introduced in 1986 and has since been adapted for use in all sites to become the standard technique in the management of paediatric burns at the Women's and Children's Hospital Burn Unit. The technique is versatile, safe, simple, reliable and inexpensive, and has proven to be effective in over 700 burn patients, with 18 patients (2%) requiring repeat grafts. The patient's care is continued in a designated Burn Scar Assessment Clinic with a range of 'contact media', including Hypafix, Elastofix, silicone gel and Elastomer products, being applied as necessary.     

Nasal Correction in Binder's Syndrome: The Evolution of a Treatment Plan

Maxillofacial dysplasia, or Binder's Syndrome is a challenge for the surgeon. The evolution of a surgical treatment plan has led to improved facial contour and patient self-image. We studied 27 patients with maxillonasal dysplasia of variable degrees, both on a short- and long-term basis. In some patients, surgical treatment began as early as 3 years of age, while others were treated as teenagers or young adults. Surgical options included cartilaginous onlay grafts to the pyriform area, nasal dorsal grafts (linear or L-strut in design), and columellar strut grafts. Le Fort osteotomies were reserved for those patients with Class III malocclusion (15% in this series). The overall goals were to augment skeletal deficiencies of the midface and begin the soft tissue expansion process as early as possible. From our long-term follow-ups (up to 15 years) it has become apparent that surgical treatment should begin early. This leads to improved self-image by the child's preschool years, taking advantage from their youthful skin elasticity. In the young patient, sequential lengthening procedures of the dorsum and columella are beneficial. Paranasal and midfacial augmentation is reserved until midfacial growth is near complete when the patient is in their midteenage years.