Novel application method of artificial dermis: one-step grafting procedure of artificial dermis and skin, rat experimental study

BACKGROUND: Currently, to treat skin defects with artificial dermis (AD), two surgical procedures where the artificial dermis grafting and another secondary skin grafting are required. The purpose of this study was to achieve simultaneous grafting of the artificial dermis and the split-skin. To enhance the wound angiogenesis, cultured endothelial cells, fibroblasts and PDWHF (platelet derived wound healing factor) were employed. METHODS: The experiment consists of following two parts: (1) Investigation to obtain faster angiogenesis into the bilayer artificial dermis: full-thickness wounds created on the back of the rats were treated with the artificial dermis (Terudermis, with silicone sheet, TERUMO Co., Japan). Prior to the artificial dermis grafting, following four groups were established; control group (AD alone, n=6), PDWHF group (AD treated with PDWHF, n=6), cultured cells group (AD treated with cultured endothelial cells and fibroblasts, n=6), combination group (AD treated with PDWHF and cultured cells, n=6). (2) Trial of one-stage grafting of the AD and the skin: simultaneous grafting of the artificial dermis and skin was performed using the same rat model. Before making skin defects, split thickness skin were harvested. Then the skin grafting was carried out immediately after the AD grafting. To allow grafting of the skin onto the artificial dermis, the AD without silicone sheet (Terudermis without silicone sheet, TERUMO Co., Japan) were used. Two groups, control group (AD alone, n=3) and treatment group (AD with PDWF and cultures, n=3) were established. RESULTS: (1) When the artificial dermis were treated with PDWHF, cultured endothelial cells and fibroblasts, vascular invasion into the artificial dermis was observed 5 days after the surgery. (2) In the treatment group, the skin grafted immediately after the artificial dermis grafting was completely taken. CONCLUSIONS: The present study revealed that treatment with PDWHF, combined with cultured endothelial cells and fibroblasts, accelerated wound angiogenesis. By this method, one-step grafting procedure of the artificial dermis and the skin is possible.     

Management of wounds with exposed bone structures using an artificial dermis and skin grafting technique

The task of managing an open wound complicated by exposed bony structures underneath is difficult, if not challenging. We have instituted a method of managing the problems in stages using an artificial dermis and skin grafting technique in 17 wounds in 15 individuals from Sept. 2006 to Feb. 2009. While all wounds were noted to assume aberrant healing processes, the majority of involved bony structures were devoid of periosteal covering compounded by various degrees of infection. Of 15 incidents, mechanical trauma was responsible for 10, chemical burns for two and electrical burns for two patients. A chronic non-healing ulcer with exposed bone formed in an old burn scar accounted for the remaining one. The regimen of surgical management consisted of initial debridement, the coverage of the resultant wound with an artificial dermis and a partial-thickness skin grafted over this dermis-like structure grown with granulation tissues. Complete wound healing was attained in 15 out of 17 with outstanding cosmetic and minimal donor-site morbidity. Despite initial failure encountered in two, the morbidities noted were low. It is especially useful in large defects that usually require flaps for coverage.     

人工真皮移植二期手术疗法对肛周化脓性汗腺炎的治疗分析

目的探讨人工真皮移植二期手术对肛周化脓性汗腺炎的治疗效果。方法选择肛周化脓性汗腺炎患者20例。在一期手术中,切除所有病变的皮肤以及表浅皮下脂肪组织,健康深层皮下脂肪组织予以保留。然后将人工真皮移植到保留的深层皮下组织上。2周后行二期手术,将中厚皮片移植到缺损皮肤。对患者移植物的成活、疾病复发以及术后9~28个月的随访表现进行评估。结果 19例患者病灶处的皮肤移植成功,仅有1例患者化脓性汗腺炎复发,这例患者再次手术后,外观恢复良好。结论人工真皮移植二期手术疗法对肛周化脓性汗腺炎具有较好的临床效果。     

Application of artificial dermis prior to full-thickness skin grafting for resurfacing the nose.

Two patients with nasal skin defects resulting from excision of rhinophyma and multiple angiofibromas were treated with artificial dermis followed by full-thickness skin grafts taken from the postauricular region. The secondary skin grafts took completely in both patients, and the postoperative results were excellent. Although a two-stage operation is required, application of artificial dermis prior to full-thickness skin grafting is a reliable method for resurfacing the nose.     

Meshed unexpanded split-thickness skin grafting for reconstruction of penile skin loss

PURPOSE: Sheets of unmeshed, split-thickness skin grafts (STSGs) have been advocated in potent men with penile skin deficiency. Since the survival of sheet grafts is rarely 100% and the appearance of unexpanded 1:1 mesh grafts is quite good, we used this technique. We report our experience with meshed, unexpanded STSGs for all penile resurfacing regardless of erectile function. MATERIALS AND METHODS: Nine consecutive patients with penile skin loss were prospectively treated between March 2001 and January 2003 with meshed STSGs to the penis. The underlying condition was Fournier's gangrene in 4 cases, chronic lymphedema in 2, skin deficiency from prior surgeries in 2 and Crohn's disease in 1. Graft thickness was 0.012 or 0.016 inches and meshing was performed in a 1:1 ratio. Meshed slits were oriented transversely without expansion and the graft juncture was located on the ventral surface in zigzag fashion. Graft take, appearance, and sexual and voiding function were assessed postoperatively. RESULTS: All 9 patients had 100% graft take. At a mean followup of 6 months a satisfactory cosmetic outcome was documented photographically in all except 1 case involving chronic penile manipulation. Erectile function and ejaculation were preserved in potent patients. CONCLUSIONS: Unexpanded meshed STSGs of penile skin loss yielded satisfactory functional and cosmetic outcomes.     

The clinical application effects of artificial dermis scaffold and autologous split-thickness skin composite grafts combined with vacuum-assisted closure in refractory wounds

To investigate the clinical application effects of artificial dermis scaffold and autologous split-thickness skin composite grafts combined with vacuum-assisted closure (V.A.C) in refractory wounds. A retrospective analysis was performed on 70 patients with refractory wounds admitted to the First Affiliated Hospital of Soochow University from June 2019 to December 2021 (44 males and 25 females, with an average age of 49.3 ± 21.4 years). There were 26 patients with chronic ulcers; 3 patients with cancerous wounds; 16 patients with hot crush injuries; and 25 patients with traumatic wounds, including 21 cases of hands, 33 cases of feet, 6 cases of upper limbs, and 10 cases of lower limbs. The patients were divided into an artificial dermis scaffold group (35 patients, including 21 males and 14 females, aged 49.5 ± 21.3 years) and a skin graft group (35 patients, including 23 males and 11 females, aged 49.1 ± 21.5 years). In the artificial dermis scaffold group, after debridement, the artificial dermis scaffold was transplanted for approximately 2 weeks until the wound surface was well vascularized, after which the autologous split-thick skin graft was transplanted. Negative pressure wound therapy was performed throughout the treatment. In the skin grafting group, after debridement, the autologous split-thickness skin graft (aSTSG) was transplanted, and negative pressure wound therapy was performed continuously. The wound healing rate; skin graft survival rate; postoperative wound infection; exudative fluid volume; subcutaneous haematoma; hospitalisation time; hospitalisation cost; Vancouver Scar Scale (VSS) score, used to evaluate the scar of the recipient area at 6 months after the operation; and the sensory disorder grading method, used to evaluate the sensory recovery of the recipient area, were compared between the two groups. All 70 refractory wounds healed. In the artificial dermis scaffold group, the skin graft survival rate was 90% (86%–95%), the hospitalisation time was 38 (29–45) days, the hospitalisation cost was 148 102 (118242–192327) yuan, and the VSS score was 1.9 ± 1.3. There were significant differences in skin graft survival rate (70% [60%–80%]), length of hospital stay (21 [14–28] days), hospitalisation cost (76 201 [39228–135 919] yuan) and VSS score [6.1 ± 3.6] between the skin graft group and the artificial dermis scaffold group (P < .05). The skin graft survival rate, scar hyperplasia and sensory recovery of the recipient area in the artificial dermis scaffold group were better than those in the skin graft group, but the hospitalisation time was relatively longer, and the hospitalisation cost was relatively higher. Wound healing rate, postoperative wound infection, exudate volume, and subcutaneous haematoma of patients in the two groups were similar, and there were no significant differences (P > .05). The artificial dermis scaffold and composite transplantation of autologous aSTSG with V.A.C can promote painless wound healing and improve the skin survival rate, skin colour and lustre, and flexible smooth texture and is conducive to less scar hyperplasia and postoperative functional exercise and recovery. This method provides a reasonable and effective scheme for the treatment of clinical refractory wounds.     

大张表皮片覆盖预防断层皮片供区瘢痕

目的介绍一种用自体大张表皮片即时覆盖断层皮片供区以预防其瘢痕生长的方法。方法用鼓式或电动取皮机切取断层皮片，厚度在0．3～0.5mm之间，用电动取皮机切取大张表皮片，厚度0．07～0．12mm（0．0028in～0．0048in），供皮区一般首选在背部、腰部、臀部或头皮，其次是胸腹和四肢；将表皮片覆盖在断层皮片供区，边缘用纳米银纱布条压紧，外加缝合或钉皮钉固定。表皮片供区和移植区内层均用油纱布，外层纳米银纱布覆盖，以缝线包压法包扎。结果从1999年11月至2003年11月共用于118例的133个整形部位。断层皮片供区移植表皮片后，无瘢痕生长，平坦，光滑，外观接近正常皮肤，但无毛囊和汗腺。表皮片供区短时间内潮红，无瘢痕增生，3个月以后逐渐接近正常皮肤。结论大张表皮片移植覆盖断层皮片供区是一种预防断层皮片供区瘢痕生长的好方法，值得推广和应用。     

去细胞异体真皮、去细胞猪真皮和自体刃厚皮移植在临床中的应用

目的观察去细胞异体真皮或去细胞猪真皮加自体刃厚皮移植在深度烧伤和整形外科中的应用效果。方法采用去细胞异体真皮或我们研制的去细胞猪真皮加自体刃厚皮移植的方法,修复各种创面119例次,比较不同创面的植皮成活率,观察应用不同部位的皮肤覆盖去细胞异体真皮或去细胞猪真皮与植皮成活的关系,并对部分病例进行了组织学观察和随访。结果削痂、切痂和切瘢创面植皮成活率分别为(93．4％±3．1)％、(92．1±4．6)％和(94．5±3．8)％,三者间差异无显著意义;去细胞异体真皮加自体刃厚皮移植与去细胞猪真皮加自体刃厚皮移植,二者植皮成活率差异无显著意义。躯干、四肢自体刃厚皮覆盖的去细胞异体真皮或去细胞猪真皮,植皮成活率分别为(93．1±4．8)％、(89．0±6．2)％,而应用刃厚头皮或自体微粒皮加异体皮覆盖的去细胞异体真皮或去细胞猪真皮,植皮成活率明显下降(P<0．05或0．01)。组织学观察,术后19个月时表皮、真皮形态正常,胶原纤维排列规则,未见胶原纤维明显增生和瘢痕化,无皮肤附件。成活的复合移植皮肤,与邻近正常肤色近似,色素沉着轻,无明显皱缩,触之软,活动度好。结论去细胞异体真皮或去细胞猪真皮加自体刃厚皮移植修复深度烧伤创面或切瘢后创面不失为一种较理想的材料。     

Penetration of antibiotics through omiderm in vitro and on split-thickness skin grafts in burn patients.

Penetration of antibiotic preparations (gentamicin, neomycin, silver sulfadiazine, mupirocin) through Omiderm, a synthetic wound covering, was tested in vitro and in 5 patients with full-thickness burns who had undergone tangential excision and split-thickness skin grafting. All antibiotic preparations tested penetrated both meshed and unmeshed Omiderm. Omiderm did not affect the zones of inhibition of antimicrobial activity as compared with controls.     

Meshgraft urethroplasty using split-thickness skin graft

Meshgraft urethroplasty has become one of the standard operative procedures for the treatment of long and complicated urethral strictures. The original method used meshed foreskin for urethral reconstruction. To extend the application of the method to circumcized patients, a split-thickness skin graft was used to construct a neo-urethra. In a first stage, a split thickness skin graft is harvested from the medical part of the thigh and transplanted alongside the opened urethra. After complete healing of this transplant, the neo-urethra is formed in a second stage 12 weeks later. Since 1980 meshgraft urethroplasty using a split-thickness skin graft has been performed in 34 patients. In all patients excellent anatomic and functional results have been achieved. This technique was found to be most useful in exccedingly long or problematic strictures, e.g. in spinal cord-injured patients.     

Tissue engineered artificial skin composed of dermis and epidermis

Abstract: We made an artificial skin comprised of a stratified layer of keratinocytes and a dermal matrix with a type I collagen containing fibroblasts. In this work, we showed keratinocyte behavior under primary culture, gel contractions varying with concentration of collagen solution, and cell growth plots in the collagen gel. The optimum behavior of dermal equivalent could be obtained using 3.0 mg/ml collagen solution and attached gel culture. The attached gel culture had a jumping effect of growth factor on cell growth at the lag phase. To develop the artificial skin, 1× 10⁵ cells/cm² of keratinocytes were cultured on the dermal equivalent at air-liquid interface. Finally, to overcome the problem that artificial skin of collagen gel was torn easily during suturing of grafting, we prepared histocompatible collagen mesh and attached the mesh to the bottom of the gel. Cultured artificial skins were successfully grafted onto rats.     

大鼠深Ⅱ度烧伤创面保留变性真皮并覆盖自体皮疗效观察

目的为探讨自体皮覆盖变性真皮修复深Ⅱ度烧伤创面的可行性提供实验依据。方法在大鼠背部造成直径3.5cm深Ⅱ度烧伤创面。伤后2—5d行创面浅层削痂保留变性真皮,同时在局部移植大张自体断层皮片。移植前和移植后不同时相点分别切取植皮区全层皮肤,光镜下观察其形态学及胶原纤维变化,并检测其生物力学改变。取移植大鼠同体背部正常皮肤作为对照指标。结果(1)保留的变性真皮为玻璃样变性。(2)大鼠自体皮移植术后7d,皮片与创面融合无法分离,光镜下可见真皮乳头及网状层。术后21d移植部位皮肤厚度、结构、形态与正常组织相似,有萎缩毛囊,胶原纤维条索密度逐渐增大接近融合。(3)鼠皮抗拉强度、最大应变值在术后逐渐增大,至60d时接近正常。结论将自体皮覆盖于变性真皮上用以修复深Ⅱ度烧伤创面,变性真皮能够逐渐复苏,使其结构、形态接近正常。     

Factors affecting success of split-thickness skin grafts in the modern burn unit

BACKGROUND: The use of early tangential excision or excision to fascia of burn wounds has led to the application of split-thickness skin grafts (STSGs) to a variety of graft beds, including dermis, granulation tissue, fat, and fascia. Because insufficient objective data are available on the effect of the graft bed on survival of an STSG, a 2-year review of success rates of STSGs on a variety of graft beds was completed. METHODS: The success rates of all 599 STSGs applied to dermis, granulation tissue, fat, and fascia in 233 consecutive burn patients (mean total body surface area [TBSA] burned, 14.5%) by one surgeon at a regional burn center over a 2-year period were reviewed. Data were analyzed to compare outcomes of STSGs on the graft beds listed and in low-risk versus high-risk groups of patients (TBSA burned < or = 35% and > 35%; age < or = 18 years and > 18 years; age < or = 55 years and > 55 years; and diabetes mellitus). One-way analysis of variance was used to compare results of STSGs on different graft beds, and tests were used to analyze differences in results of STSGs in low-risk versus high-risk groups (p < 0.05, significant). RESULTS: The mean success rate at 14 days for all 599 STSGs applied in the 233 patients was 90 +/- 22%. The success rate of STSG on the various surfaces ranged from 85% (fascia) to 93% (dermis; granulation), but the differences among the four graft beds were not significant. Total body surface area burned (> 35%), older age (> 55 years), and the presence of diabetes mellitus each had a significant impact on the percentage take of STSGs at 14 days after application. CONCLUSION: In the hands of an experienced burn surgeon, the recipient bed has no significant impact on the success rate of STSGs at 14 days postgrafting, except in those patients 18 years or younger, in which the mean STSG success rate was significantly greater on granulation tissue compared with fat. TBSA burned > 35%, age > 55 years, and the presence of diabetes mellitus continue to have an adverse impact on the success rate of STSGs at 14 days.     

Successful reconstruction of full-thickness skin defects in a swine model using simultaneous split-thickness skin grafting and composite collagen microstructured dermal scaffolds

Reconstitution of normal skin anatomy after full-thickness skin loss may be accomplished using a combination of a dermal regeneration template (DRT) and a split thickness skin graft (STSG). However, because of the relatively low rate of cell infiltration and vascularisation of currently available DRTs, reconstruction is almost always performed in a two-step procedure over the course of several weeks, resulting in multiple dressing changes, prolonged immobilisation and increased chance of infection. To mitigate the potential complications of this prolonged process, the collagen-based dermal template DermiSphere™ was developed and tested in a single-step procedure wherein DermiSphere and STSG were implanted simultaneously. When evaluated in a porcine, full thickness, excisional wound model, DermiSphere successfully supported simultaneous split thickness skin graft take and induced functional neodermal tissue deposition. When compared to a market leading product Integra Bilayer Wound Matrix, which was used in a multistep procedure (STSG placed 14 days after product implantation according to the product IFU), DermiSphere induced a similar moderate and transient inflammatory response that produced similar neodermal tissue maturity, thickness and vascularity, despite being implanted in a single surgical procedure leading to wound closure 2 weeks earlier. These data suggest that DermiSphere may be implanted in a single-step procedure with an STSG, which would significantly shorten the time course required for the reconstruction of both dermal and epidermal components of skin after full thickness loss.     

Antecedent thermal injury worsens split-thickness skin graft quality: A clinically relevant porcine model of full-thickness burn,excision and grafting

Current standard of care for full-thickness burn is excision followed by autologous split-thickness skin graft placement. Skin grafts are also frequently used to cover surgical wounds not amenable to linear closure. While all grafts have potential to contract, clinical observation suggests that antecedent thermal injury worsens contraction and impairs functional and aesthetic outcomes. This study evaluates the impact of antecedent full-thickness burn on split-thickness skin graft scar outcomes and the potential mediating factors. Full-thickness contact burns (100 °C, 30 s) were created on the backs of anesthetized female Yorkshire Pigs. After seven days, burn eschar was tangentially excised and covered with 12/1000th inch (300 μm) split-thickness skin graft. For comparison, unburned wounds were created by sharp excision to fat before graft application. From 7 to 120 days post-grafting, planimetric measurements, digital imaging and biopsies for histology, immunohistochemistry and gene expression were obtained. At 120 days post-grafting, the Observer Scar Assessment Scale, colorimetry, contour analysis and optical graft height assessments were performed. Twenty-nine porcine wounds were analyzed. All measured metrics of clinical skin quality were significantly worse (p < 0.05) in burn injured wounds. Histological analysis supported objective clinical findings with marked scar-like collagen proliferation within the dermis, increased vascular density, and prolonged and increased cellular infiltration. Observed differences in contracture also correlated with earlier and more prominent myofibroblast differentiation as demonstrated by α-SMA staining. Antecedent thermal injury worsens split-thickness skin graft quality, likely by multiple mechanisms including burn-related inflammation, microscopically inadequate excision, and dysregulation of tissue remodeling. A valid, reliable, clinically relevant model of full-thickness burn, excision and skin replacement therapy has been demonstrated. Future research to enhance quality of skin replacement therapies should be directed toward modulation of inflammation and assessments for complete excision.     

Management of chronic perineal sinuses by wide excision and split-thickness skin grafting

Nine patients who had chronic perineal sinuses following proctectomy for inflammatory bowel disease underwent wide excision of the sinus and split-thickness skin grafting. All patients had persistent pain and discharge. All but one had undergone multiple surgical procedures previously. Fibrous tissue was excised from the sinus tract and the wound was grafted either immediately (six patients) or at a later date (three patients). Five patients had complete healing of the wound initially while four required further procedures. Eight patients have been followed up for an average of 4.6 years (range from 5 months to 12 years). Complete healing was achieved in seven patients; all are free of pain and can work or are unrestricted in their daily activities. One patient is improved but still requires analgesia and is disabled by the persistent pelvic pain.