Prefabrication of large fasciocutaneous flaps using an isolated arterialised vein as implanted vascular pedicle.

Flap prefabrication represents a new trend in microsurgical tissue transfer. Based on the concept of neovascularisation, in Chinchilla Bastard rabbits (n=40), an isolated venous pedicle dissected from the femoral and saphena magna vein was arterialised by end-to-end anastomosis to the femoral artery at the inguinal ligament. This arterialised venous loop was implanted beneath a random-pattern vascularised abdominal fasciocutaneous flap as large as 8 x 15 cm(2) to investigate the development of neovascularisation at various evaluating times of 4, 8, 12, 16 and 20 days. To prevent neoangiogenesis from occurring between the underlying vascular bed and abdominal flap, a silicone sheet with the corresponding dimension of 8 cm x 15 cm x 0.25 mm was placed and fixed on the abdominal wall. The flap viability and the neovascularisation process in the prefabricated abdominal skin flaps were evaluated by macroscopic observation, blood analysis, selective microangiography and histology. The experimental results showed that newly formed vessels originating from the implanted isolated venous pedicle were evident on the angiograms 4 days after pedicle implantation. In the 8- and 12-day groups, newly formed vessels became larger and some were connected to the originally available vasculature in the abdominal fasciocutaneous flaps. In the 20-day group, entire flaps were perfused by the blood flow supplied from the newly implanted venous pedicles through newly formed vessels and their vascular connections. This study indicated that large flap prefabrication can be created by implantation of an isolated arterialised venous pedicle into a random-pattern vascularised fasciocutaneous flap. Twenty days appears to be the minimal length of time required after arterialised venous pedicle implantation for the maturation of neovascularisation in the prefabricated flap.     

颞浅血管预构扩张皮瓣的临床应用

目的:探讨颞浅血管预构扩张皮瓣在修复面、颈部较大皮肤软组织缺损中的应用及其修复效果。方法:通过将颞浅动、静脉植入颈部皮下,皮下置入扩张器,经过3个月的组织扩张,形成以颞浅动、静脉为蒂的颈部预构扩张皮瓣,转移修复同侧面、颈部的皮肤软组织缺损。结果:2001年至2006年,应用此方法修复10例面、颈部瘢痕挛缩患者的面颊部及颏颈部皮肤软组织缺损,均取得了成功。随访6个月,效果满意。结论:采用颞浅动、静脉颈部预构扩张皮瓣修复面、颈部皮肤软组织缺损是一种可行的方法。     

兔股动脉和静脉预构轴型扩张皮瓣的实验观察

目的 通过兔股动脉、静脉预构轴型扩张皮瓣的微循环血流晕动态变化、光镜下结构的改变及其成活面积,为预构轴型扩张皮瓣的临床应用提供依据.方法 选择新西兰白兔40只,随机分为4组:预构轴型扩张皮瓣组、预构轴型不扩张皮瓣组、单纯预构轴型皮瓣组及无蒂游离皮瓣组,每组4只,前2组股动脉、静脉移位后,预构轴型扩张皮瓣组、预构轴型不扩张皮瓣组分别在肉膜深面置入容量为50 ml长方形皮肤软组织扩张器,预构轴型扩张皮瓣组7 d后开始注水;无蒂游离皮瓣组为对照组,未采取预构及扩张处理.定期对4组皮肤进行微循环血流量检测,并取样进行光镜观察.预构术后52 d,前3组形成以预构股动静脉血管束为蒂的岛状皮瓣,游离皮瓣组则形成无蒂游离皮瓣后均原位缝合,观察其成活面积.结果 预构轴型扩张皮瓣组较其他组微循环血流量增加,成活面积大[(97.54±2.73)%],光镜下改变显著(P<0.05).结论 扩张术能促进预构轴型皮瓣的血管化进程,明显增大预构轴型皮瓣成活面积,增加其移植的安全性.     

Neovascularization and free microsurgical transfer of in vitro cartilage-engineered constructs

Cartilage tissue engineering shows to have tremendous potential for the reconstruction of three-dimensional cartilage defects. To ensure survival, shape, and function, in vitro cartilage-engineered constructs must be revascularized. This article presents an effective method for neovascularization and free microsurgical transfer of these in vitro constructs. Twelve female Chinchilla Bastard rabbits were used. Cartilage-engineered constructs were created by isolating chondrocytes from auricular biopsies, amplifying in monolayer culture, and then seeding them onto polycaprolactone scaffolds. In each prefabricated skin flap, three in vitro cartilage-engineered constructs (2 x 2 x 0.5 cm) and one construct without cells (served as the control) were implanted beneath an 8 x 15 cm random-pattern skin flap, neovascularized by implantation of an arteriovenous vascular pedicle with maximal blood flow. Six weeks later, the neovascularized flaps with embedded cartilage-engineered constructs were completely removed based on the newly implanted vascular pedicle, and then freely retransferred into position using microsurgery. Macroscopic observation, selective microangiography, histology, and immunohistochemistry were performed to determine the construct vitality, neovascularization, and new cartilage formation. The results showed that all neovascularized skin flaps with embedded constructs were successfully free-transferred as free flaps. The implanted constructs were well integrated and protected within the flap. All constructs were well neovascularized and showed histologically stability in both size and form. Immunohistology showed the existence of cartilage-like tissue with extracellular matrix neosynthesis.     

Delayed prefabricated arterial composite venous flaps: an experimental study in rabbits

Prefabrication of composite arteriovenous flaps with implantation of an autologous graft (cartilage) or an alloplastic material (porous polyethylene) was studied in 40 rabbits. Abdominal flaps based on bilateral epigastric pedicles were elevated. An ear cartilage graft or a porous polyethylene implant was inserted under the flap. Two weeks after the operation, 10 flaps with cartilage graft and 10 flaps with porous polyethylene were raised, converted to arteriovenous flaps, and resutured in place in the experimental groups. In the other 20 rabbits of the control groups, the flaps (10 with cartilage graft and 10 with porous polyethylene) were raised and resutured in place as conventional axial flaps. At the end of the second and fourth week postoperatively, samples were obtained from the flap tissues (including a part of the graft or implantation material) and were prepared for histologic examination in all rabbits. The viable areas of all flaps were assessed at the end of fourth week after the second operation. The mean survival rates were 99.4%, 99.7%, 99.5%, and 99.8% in the arteriovenous and control flaps prefabricated with cartilage graft and the arteriovenous and control flaps prefabricated with porous polyethylene respectively. The features of wound healing in the experimental and control groups were similar. The study showed that arteriovenous perfusion can nourish a prefabricated flap containing an implanted material (autologous or alloplastic) and these 2-week delayed composite flaps have a similar survival rate to delayed prefabricated conventional axial flaps.     

Use of free interpositional vein grafts as pedicles for prefabrication of skin flaps

Pedicles created from a long vein graft increase the scope and applications of prefabricated skin flaps. This study reports the survival and pattern of neovascularization of lower abdominal skin flaps in rabbits based on a pedicle formed by interposition of a long vein graft between the divided ipsilateral femoral artery and vein. Flaps were elevated 2–5 weeks after pedicle implantation and the surviving area quantitated and vascular patterns examined 1 week later. Only 8 out of 35 flaps were greater than 50% alive, the most frequent cause of flap failure being pedicle non-patency. If the pedicle remained patent, complete flap survival was possible as early as 2 weeks after implantation. In non-patent pedicles, recanalization or formation of a new vascular network may, given at least 4 weeks, be sufficient to ensure partial flap survival. The findings indicate that implantation of a long, skeletonized vein graft is an unreliable method of prefabrication of abdominal skin flaps in this model. © 1994 Wiley-Liss, Inc.     

Impact of tissue expansion on flap prefabrication: An experimental study in rabbits

This study was designed to determine whether tissue expansion after vascular pedicle implantation would increase the survival area of prefabricated skin flaps. In 20 New Zealand white rabbits, the vascular pedicle consisting of the central artery and vein of the left ear was implanted into the neck. At the time of pedicle implantation a subcutaneous pocket was created measuring 5 × 14 cm beneath the implantation site. Tissue expanders of three different sizes and volumes were implanted in the rabbits of three treatment groups. No tissue expander was implanted in the animals of the control group. All flaps were transposed after 3 weeks to the contralateral ear, and flap survival was assessed 1 week later. The increased area of the flap survival was statistically significant in all three treatment groups compared to the nonexpanded flaps (P = 0.003, P = 0.004, P < 0.0001, respectively). In addition there was a statistically significant larger area of survival using a 100-cc expander measuring 5 × 14 cm (the same size as the elevated flap) compared to 40-cc (3 × 5 cm) or to 60-cc (4 × 8 cm) expanders (P < 0.001, P = 0.004, respectively). The one-way analysis of variance and the t-test were used to show statistical differences. We conclude that the time necessary for neovascularisation of the skin flap could be used to expand the tissue, not only increasing the amount of available tissue, but also enhancing the vascularity. © 1996 Wiley-Liss, Inc.     

血管内皮细胞生长因子和碱性成纤维细胞生长因子加速预构扩张皮瓣成熟的研究

目的　观察以生物蛋白胶局部缓释血管内皮细胞生长因子 (VEGF)和碱性成纤维细胞生长因子(b FGF)应用于兔预构扩张皮瓣对细胞增殖及凋亡、血管化进程 ,以及皮瓣成熟的作用。　方法　将新西兰大耳白兔 5 3只随机分为正常、空白、生物蛋白胶、VEGF直接应用、VEGF胶及 b FGF胶共 6组 ,兔耳中央动静脉束植入预构扩张皮瓣 ,14天后形成 3cm× 5 cm岛状瓣。分别进行皮瓣成活面积、激光多普勒血流量、铅丹灌注、墨汁灌注、PCNA免疫组化和 TUNEL 凋亡检测。　结果　两种生长因子应用组皮瓣成活面积较其它组增加 ,血流灌注量增多 ,新生毛细血管密度加大 ,细胞增殖提高、凋亡减少。　结论　 VEGF和 b FGF均能通过刺激细胞增殖和减少凋亡发生来促进血管新生和预构扩张皮瓣成熟 ,用生物蛋白胶缓释生长因子有独特效果。     

Gene therapy with adenovirus-mediated VEGF enhances skin flap prefabrication

We investigated the feasibility in rats of enhancing skin-flap prefabrication with subdermal injections of adenovirus-encoding vascular endothelial growth factor (Ad-VEGF). The left saphenous vascular pedicle was used as a source for vascular induction. A peninsular abdominal flap (8 x 8 cm) was elevated as distally based, keeping the epigastric vessels intact on both sides. After the vascular pedicle was tacked underneath the abdominal flap, 34 rats were randomly divided into three groups according to treatment protocol. The implantation site around the pedicle was injected with Ad-VEGF in group I (n = 10), with adenovirus-encoding green fluorescent protein (Ad-GFP) in control group I (n = 14), and with saline in control group II (n = 10). All injections were given subdermally at four points around the implanted vessel by an individual blinded to the treatment protocol. The peninsular flap was sutured in its place, and 4 weeks later, an abdominal island flap based solely on the implanted vessels was elevated. The prefabricated island flap was sutured back, and flap viability was evaluated on day 7. Skin specimens were stained with hematoxylin and eosin for histological evaluation. In two rats from each group, microangiography was performed to visualize the vascularity of the prefabricated flaps. There was a significant increase in survival of prefabricated flaps in the Ad-VEGF group compared to the control groups: Ad-VEGF, 88.9 +/- 6.1% vs. Ad-GFP, 65.6 +/- 9.4% (P < 0.05) and saline, 56.0 +/- 3.4% (P < 0.05). Sections from four prefabricated flaps treated with Ad-GFP revealed multiple sites of shiny deposits of green fluorescent protein around the area of local administration 1 day and 3 weeks after gene therapy. Histological examination done under high-power magnification (x400) with a light microscope revealed increased vascularity and mild inflammation surrounding the implanted vessel in all groups. However, we were unable to demonstrate any significant quantitative difference with respect to vascularity and inflammatory infiltrates in prefabricated flaps treated with Ad-VEGF compared with controls. Microangiographic studies showed increased vascularity around the implanted pedicle, which was similar in all groups. However, vascularization was distributed in a larger area in the prefabricated flaps treated with Ad-VEGF. In this study, the authors demonstrated that adenovirus-mediated VEGF gene therapy increased the survival of prefabricated flaps, suggesting that it may allow prefabrication of larger flaps and have the potential to reduce the time required for flap maturation.     

缺血-再灌注损伤对扩张皮瓣转移术后的影响

目的：探讨缺血-再灌注损伤对扩张皮瓣转移术后的影响。方法：以实验兔每侧腹壁浅动脉为中线,于两侧腹部植入50ml软组织扩张器各一只,术后定期注水扩张至80ml为止。分别于扩张皮瓣转移前、转移后1h、24h、72h检测腹壁浅动脉血流速度,切取皮瓣远端组织在200倍光镜下进行白细胞计数,检测皮瓣组织中丙二醛（MDA）、髓过氧化物酶（MPO）含量。结果：扩张皮瓣转移前腹壁浅动脉的血流速度为（13.2±0.78）cm/s,光镜下白细胞计数为（8.33±2.61）个,皮瓣组织内MDA含量为（1.72±0.57）nmol/mgprot,MPO含量为（126.50±20.70）U/g。皮瓣转移术后1h血流速度为（6.22±0.93）cm/s,白细胞计数为（19.08±4.94）个,MDA含量为（4.05±0.67）nmol/mgprot,MPO含量为（349.42±27.27）U/g。皮瓣转移术后24h血流速度为（8.37±0.56）cm/s,白细胞计数为（60.17±6.24）个,MDA含量为（6.68±0.73）nmol/mgprot,MPO含量为（558.08±26.99）U/g。皮瓣转移术后72h血流速度为（17.36±1.06）cm/s,白细胞计数为（34.00±3.79）个,MDA含量为（2.51±0.41）nmol/mgprot,MPO含量为（215.92±25.97）U/g。结论：在扩张皮瓣转移术后发生缺血-再灌注的过程中,皮瓣组织发生再灌注损伤。     

Post-burn head and neck reconstruction using tissue expanders

Tissue expanders have become useful adjuvants in reconstruction after burn. This study reviews experience with of tissue expanders in the treatment of head and neck burns, from April 2002 to February 2007; 82 expanders were used for 72 patients, all of whom underwent reconstruction at least 6 months after complete healing. The only major difference in this study from other techniques was the preoperative approach for selecting flaps and implants. The use is described of tissue expanders to enhance the area and provide suitable tissue for large expanded flaps for reconstruction of the face and neck. This was based on previous laboratory studies demonstrating that large flaps with very narrow pedicles remain well vascularised and can be transposed to cover very large defects. Satisfactory results were achieved after reconstruction in all cases. Tissue expansion, if carefully planned and conducted, is part of the treatment of choice for post-burn reconstruction of the head and neck, allowing an expanded flap suitable for versatile coverage.     

Use of fascial grafts as an interface in flap prefabrication: an experimental study.

An experimental study was conducted to investigate whether a fascial graft can be used as an interface between a vascular pedicle and target tissue to augment tissue survival in a prefabricated flap. Thirty-six male Sprague-Dawley rats were divided into three experimental groups according to the type of the recipient bed prepared for the vascular implantation. The left saphenous vascular pedicle was used as the vascular source. A 9 x 9-cm inferiorly based peninsular abdominal flap was elevated in each animal. In group I, the pedicle was tacked beneath the abdominal flap, in which the epigastric fascial layer was untouched. In group II, a 3 x 5-cm graft of epigastric fascia was harvested from the abdominal flaps under loupe magnification. The graft was sutured back into its original position after a 180-deg rotation. The vascular pedicle was then implanted just beneath the center of the fascial graft. In group III, the same size of epigastric fascia was removed in the same manner as group II, exposing the subcutaneous layer for pedicle implantation. Four weeks later, abdominal flaps were raised as island flaps connected only to the saphenous pedicle and were sutured in place. Flap viability was assessed visually on day 7. Overall, the ultimate flap survival in group I was the largest, with some necrotic areas at the periphery of the flaps. In group II, flap survival was typically centralized over the fascial graft, and crescent-shaped necrosis was noted superiorly. In group III, an almost linear pattern of survival overlying the vascular pedicle was observed. The mean surviving flap area of group I (12.13 +/- 1.615 cm2) was statistically greater than that of group II (8.83 +/- 0.663 cm2, p < 0.001) and group III (6.3 +/- 0.815 cm2; p < 0.001). There was a statistically significant difference between the mean flap survival in groups II and III (p < 0.001). Vascular arborization was examined by microangiography, and specimens were processed for histological staining. In group II, vascularization was distributed in a larger area along the fascial graft in comparison with limited vascularization around the pedicle in group III. In this study it was revealed that the interposition of a fascial graft as an interface between the vascular source and the target tissue seems to increase the size of the prefabricated flap.     

Face resurfacing using a cervicothoracic skin flap prefabricated by lateral thigh fascial flap and tissue expander

Background: Resurfacing of facial massive soft tissue defect is a formidable challenge because of the unique character of the region and the limitation of well‐matched donor site. In this report, we introduce a technique for using the prefabricated cervicothoracic skin flap for facial resurfacing, in an attempt to meet the principle of flap selection in face reconstructive surgery for matching the color and texture, large dimension, and thinner thickness (MLT) of the recipient. Materials: Eleven patients with massive facial scars underwent resurfacing procedures with prefabricated cervicothoracic flaps. The vasculature of the lateral thigh fascial flap, including the descending branch of the lateral femoral circumflex vessels and the surrounding muscle fascia, was used as the vascular carrier, and the pedicles of the fascial flap were anastomosed to either the superior thyroid or facial vessels in flap prefabrication. A tissue expander was placed beneath the fascial flap to enlarge the size and reduce the thickness of the flap. Results: The average size of the harvested fascia flap was 6.5 × 11.7 cm. After a mean interval of 21.5 weeks, the expanders were filled to a mean volume of 1,685 ml. The sizes of the prefabricated skin flaps ranged from 12 × 15 cm to 15 × 32 cm. The prefabricated skin flaps were then transferred to the recipient site as pedicled flaps for facial resurfacing. All facial soft tissue defects were successfully covered by the flaps. The donor sites were primarily closed and healed without complications. Although varied degrees of venous congestion were developed after flap transfers, the marginal necrosis only occurred in two cases. The results in follow‐up showed most resurfaced faces restored natural contour and regained emotional expression. Conclusion: MLT is the principle for flap selection in resurfacing of the massive facial soft tissue defect. Our experience in this series of patients demonstrated that the prefabricated cervicothoracic skin flap could be a reliable alternative tool for resurfacing of massive facial soft tissue defects. © 2009 Wiley‐Liss, Inc. Microsurgery, 2009.     

Free flap transfer bridged by antegrade and retrograde posterior tibial vessel flaps temporally borrowed from the healthy leg

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Prefabrication of combined composite (chimeric) flaps in rats

The purpose of this study was to prefabricate a new combined composite (chimeric) flap that consists of four different tissues. The tissues were prefabricated around two independent pedicles that ultimately join as a single main pedicle. In the inguinal area of 36 rats, the saphenous and the superficial inferior epigastric (SIE) pedicles were dissected and prepared as vascular carriers. A fascial graft and a local muscle flap were wrapped around the saphenous pedicle. The SIE pedicle was then implanted under the abdominal skin to supply a future skin flap. An ear cartilage graft was also inserted under the abdominal skin and adjacent to the implanted SIE pedicle. After allowing 2-, 4-, 6-, and 12-week prefabrication periods in different groups of nine animals, the prefabricated tissues were raised around two pedicles nourished by the femoral pedicle and then transferred. Flap survival was assessed by observation, microangiography and histology. The skin flaps showed survival rates of 52 +/- 17% (mean +/- standard error of the mean), 64 +/- 16%, 86 +/- 11%, and 100 +/- 0% of the total areas in the 2-, 4-, 6-, and 12-week prefabricated flaps respectively. None of the control grafts that were prepared on the contralateral side survived totally. A significant difference was found between the 12- and 2-week (p < 0.008), 12- and 4-week (p < 0.02), and 6- and 2-week (p < 0.05) prefabrication groups. Histologically, fascial and cartilage grafts, and portions of muscle were viable in the 2- and 4-week groups. Also, noticeable necrosis was found in the skin flaps in these groups. The muscle showed mild (at 2, 4, and 6 weeks) and moderate (at 12 weeks) atrophy. After prefabrication for 6 weeks, all tissues demonstrated good survival. This study shows that a combined composite flap can be prefabricated successfully in rats after a 6-week period of prefabrication.     

Vascularization of skin following implantation of an arteriovenous pedicle: implications in flap prefabrication.

In a rat model, a skin flap was fabricated by implantation of a distally ligated arteriovenous pedicle. The femoral artery and vein were implanted as a unit beneath the abdominal skin, a portion of which was later raised as an island flap, based on these vessels. Percentage area of survival, tissue blood flow, and pattern of vascularity were compared in two groups of flaps. In group I, the pedicle to be implanted was dissected with a cuff of surrounding muscle still attached; in group II, the pedicle was skeletonized to the level of adventitia. Flap survival in the two groups was similar (73% vs. 77%), as was skin blood flow (5.4 vs. 5.7 ml/100 g/min). Angiography demonstrated two principal patterns of vascularization: connection between donor and recipient vessels (inoculation), and sprouting and arborization of new vessels. Strengths and limitations of this and other models of flap "prefabrication" are discussed.     

Prefabrication of skin flaps using vein grafts: an experimental study in rabbits.

Prefabrication provides a new method for creating donor sites which are not limited by natural vascular territories. There are several methods for prefabrication, and these include implantation of greater omentum, blood vessels or muscle flaps. Based on the concept that an arterio-venous (A-V) shunt results in sufficient neovascularisation to support a free flap, we used a rabbit model to investigate the characteristics of these flaps. Prefabrication of an abdominal wall donor site was performed using the left epigastric vein in 20 male New Zealand white rabbits. An 8 x 10 cm skin flap was elevated 10 days after prefabrication, either as an island or a free flap. Survival of the skin flaps exceeded 93% and was independent of position of the vascular pedicle, direction of blood flow, or nature of the flap (island or free flap). Angiograms showed a very rich neovascularisation within the prefabricated flap.     

扩张后皮瓣修复面颈部瘢痕挛缩畸形

目的 了解扩张后皮瓣治疗面颈部烧伤后瘢痕挛缩畸形的效果.方法 利用83个皮肤扩张器对38例烧伤后面颈部瘢痕挛缩畸形患者进行治疗.扩张器容量为100～600 mL,扩张时间3～5个月.扩张器置入部位大部分为正常皮肤,但其中10个扩张器置入烧伤后稳定软化的瘢痕下.扩张后行皮瓣转移术.本组有3例患者的扩张器置于斜方肌下部深筋膜层内,行以颈横动脉深支为蒂的远位扩张皮瓣移植.结果 38例患者术后皮瓣均成活,效果满意.其中8例术后发生血肿、感染等并发症,经处理后均未影响治疗效果.30例患者随访3～24个月,皮瓣颜色、质地均佳,外形及功能明显改善.结论 扩张后皮瓣是治疗面颈部烧伤后瘢痕畸形的最佳方法.在局部无正常皮肤的情况下,扩张瘢痕皮肤及远位扩张也是良好的选择.     

扩张后胸三角皮瓣修复面颈部大面积瘢痕

目的:探讨胸三角皮瓣预扩张后,带蒂转移修复面颈部大面积瘢痕的治疗效果。方法:根据面颈部瘢痕范围,采用单侧或双侧胸三角皮瓣预扩张,选用500～600ml扩张器置入胸三角区,经2～4个月快速注水,注水总量可达1200～1800ml,获得足够皮肤后先行扩张皮瓣延迟术,2周后再切除面颈部瘢痕,创面应用扩张后胸三角皮瓣转移覆盖,供区直接拉拢缝合,待转移皮瓣夹管训练时间大于1h后断蒂,利用蒂部皮瓣来修复剩余瘢痕切除松解后的创面。结果:本组19例面颈部大面积瘢痕患者,共计26个胸三角皮瓣,1个皮瓣远端局部血运障碍,余皮瓣术后均成活好,皮瓣色泽、厚度、质地与周围皮肤相近,解决了瘢痕导致的组织畸形,患者及家属对总体效果满意。结论:扩张后胸三角皮瓣是修复面颈部大面积瘢痕的好方法。     

Flap prefabrication and prelamination with tissue-engineered cartilage

In reconstructive surgery, the integration of tissue-engineered cartilage in a prefabricated free flap may make it possible to generate flaps combining a variety of tissue components, to meet the special requirements of particular defects. One aim of the present study was to investigate prefabrication of a microvascular free flap by implanting a vessel loop under a skin flap in a rabbit model. A second aim was to report on the authors' preliminary experiences in prelaminating prefabricated flaps with autologous tissue-engineered cartilage, in terms of matrix development, inflammatory reaction, and host-tissue interaction. The flap was prefabricated by implanting a vessel loop under a random-pattern abdominal skin flap. The tissue-engineered cartilage constructs were made by isolating chondrocytes from auricular biopsies. Following a period of amplification, the cells were seeded onto a non-woven scaffold made of a hyaluronic-acid derivative and cultivated for 2 weeks. One cell-biomaterial construct was placed beneath the prefabicated flap, and two additional constructs were placed subcutaneously and intramuscularly. In addition, a biomaterial sample without cells was placed subcutaneously to provide a control. All implanted specimens were left in position for 6 or 12 weeks. Neovascularization in the prefabricated flap and biomaterial construct was analyzed by angiography. After explantation, the specimens were examined by histologic and immunohistochemical methods. The prefabricated flaps showed a well-developed network of blood vessels between the implanted vessel loop and the original random-pattern blood supply. The tissue-engineered constructs remained stable in size and showed signs of tissue similar to hyaline cartilage, as evidenced by the expression of cartilage-specific collagen type II and proteoglycans. No inflammatory reactions were observed. The physiologic environment of the autologous rabbit model provided favorable conditions for matrix deposition and maturation of the cell-biomaterial constructs. These initial results demonstrated the potential of prefabricating an axial perfused flap, combined with tissue-engineered cartilage, thus creating functionally competent tissue components for reconstructive surgery with minimal donor-site morbidity.