Challenge In Reconstructive Surgery Research Articles

Auricular reconstruction with the use of a modified rhomboid flap

Sir, We describe a simple, safe one-stage procedure for reconstruction of marginal helical defects. Auricular reconstruction after trauma, burn or local excision of tumours has been a common challenge in plastic surgery. Apart from functional importance, the ear also has great aesthetic value, because it frames the face and provides symmetry. A common defect on the ear is partial loss of the helical margin with or without a cartilage defect. Keeping general principles in mind, one can consider various surgical options, based on a reconstructive triangle approach. One effective solution is the use of the rhomboid flap [1]. The skin defect over the superior part of the ear can be covered by a superiorly based random pattern post-auricular flap designed on the non-hair bearing area, this has the advantage of having the same skin colour as the original auricular skin (Figs. 1, 2, 3 and 4). Although the dimensions and shape of both defect and flap are precise, they are variables in planning, namely which of four potential flaps should be used, and the axis around which the excisional rhomboid is be drawn. It is possible to manipulate these variables in such a way that closure of the secondary defect makes use of the laxity of the skin present (use of Dufourmental instead of Limberg flap). A further advantage of this flap is that the donor site scarring comes to lie behind the ear and is, therefore, inconspicuous. The anterior edge of the flap can be cut along the retroauricular sulcus. The greater skin mobility on the post-auricular surface, coupled with the fact that ear tolerates being set back closer to the head, increases the role of this flap considerably. There is some loss of the curve of the helical margin, but patients tend to be in an older age group and thus the result can be acceptable. For small defects, a simple transposition flap that is designed as a formal rhomboid flap is a useful option (Figs. 5, 6). In this situation, Fortier-Riberdy et al. gave some useful tips [2]:

Use of Instrumentation in the Correction of Congenital Spinal Deformities

Growth imbalance of the vertebrae leads to three dimensional deformities of the spinal column in congenital spinal deformities. Deformities are often rigid and create serious challenge for reconstructive surgery. In-situ fusions were popular before use of instrumentation in congenital spinal deformities. Combined anterior-posterior fusions of the vertebral column were performed to stop the progression of the curves. Unique problems in congenital spinal deformity like shorter spinal/trunk length and thoracic insufficiency syndrome are worsened due to shortening of the spine in time after conventional fusion treatments. Spine is stiff in congenital spinal deformities and all surgical interventions increase rigidity by reducing the amount of mobile segments. Spinal canal compromises observed in congenital deformities and associated spinal cord anomalies may increase the risk of neurologic injury following surgical manipulation. Aim of the treatment should be to obtain optimal and safe corrections with lesser segment solid fusions, preventing the adding on and crankshaft phenomena with a minimum number of surgical procedures. Modern surgical techniques enabled us to straighten the spines as achieve solid fusions. Now, it is possible to obtain significant level of reconstruction via instrumented fusion on congenital spinal deformities. Modern anesthesiology methods, developments in imaging procedures and neuromonitorization techniques as well as newer implant technologies enable spine surgeons to deal with complicated congenital spinal deformities. We aimed to review the current instrumented treatment modalities for congenital spinal deformities and the difficulties faced during instrumentation of the congenitally deformed spine.

A new alternative for reconstruction of soft triangle defects secondary to burn injury: Superiorly based columellar flap

Nasal reconstruction following severe burn injury remains a challenge in plastic surgery. In burn patients, the external nares and the soft triangle are commonly affected subunits of the nose where local tissue deficit and scar contraction during the recovery period contribute to soft triangle deformity and alar stenosis. These patients usually have associated facial burns with varying severity, which significantly limit the availability of local flaps. Reconstruction with skin grafts often yields unsatisfactory results because of the mismatch in colour and texture in addition to the primary and secondary contraction phenomena. The use of superiorly based columellar flap, which has yielded satisfactory results on a female patient, would be a new and reliable option for reconstruction of the soft triangle deficit with alar stenosis.

Improvement of Skin Quality after Fat Grafting: Clinical Observation and an Animal Study

Restoration of volume and contour defects is a challenge in plastic surgery. Autologous fat tissue transfer is gaining increasing popularity in this field. The aim of this study was to investigate the histologic modifications of the skin after fat tissue grafting on an animal model. Thirty nude mice, divided into three groups, were used in the experiment. All 30 mice received human fat tissue on one side. On the opposite side, 10 mice received nothing (negative control group), 10 mice received cell proliferation medium, and the remaining 10 mice received only subcutaneous tunneling. Eight weeks later, biopsies of the skin and subcutaneous tissue were performed and specimens were analyzed by hematoxylin-phloxin-saffron staining. Dermis thickness was measured. To differentiate human from murine collagen fibers, human and murine collagen type I antibodies were used. The other types of collagen were investigated by immunohistochemistry (immunostaining) using collagen type III, V, and VI antibodies. Fat tissue was found in all animals. Macroscopically, fat tissue presented normal aspects, with abundant peripheral neovascularization. Histologic examination showed abundant extracellular matrix around the injected human fat tissue. This was attributable to increased type I collagen fibers of murine origin as a result of the murine fibroblast stimulation by the grafted human fat tissue. Dermal thickness after fat grafting was significantly greater. This was not attributable to inflammatory reactions, because no modification was detected in our control groups. This study shows that fat tissue grafting stimulates a neosynthesis of collagen fibers at the recipient site and makes the dermis thicker. However, the long-term effects remain undetermined and need further investigation.

Large posterior chest wall defect reconstructed with a de-epithelised trans-thoracic TRAM flap

Extensive posterior chest wall defects, especially those closer to the midline of the trunk, pose surgical challenges in plastic surgery. In these cases, prior to tissue coverage, the status of the pleural cavity and skeletal support need to be addressed to obtain a functional and anatomical reconstruction. We recently operated upon a patient presenting with an aggressive ossifying fibromyxoid tumour located in the lower dorsal paraspinal region on the right side. After ablative surgery and intra-operative radiotherapy, a broad defect in the chest wall of 15 x 10 cm, including the proximal part of five posterior ribs, was presented. It required immediate bony frame reconstruction, which was resolved with a Goretex patch wrapped with a de-epithelised myocutaneous pedicled transverse rectus abdominus myocutaneous (TRAM) flap, transposed through the right hemithorax. The patient was extubated 2 days after surgery and discharged in 10 days. We describe the use of an intra-thoracic TRAM flap to reach the posterior chest wall defects, and we propose its specific indication for reconstruction of extensive posterior chest wall defects when other options are unavailable.

Latissimus dorsi/rib intercostal perforator myo-osseocutaneous free flap reconstruction in composite defects of the scalp: case series and review of literature.

Adequate coverage of complex, composite scalp defects in previously radiated, infected, or otherwise compromised tissue represents a challenge in reconstructive surgery. To provide wound closure with bony protection to the brain, improve cranial contour, and prevent or seal cerebrospinal fluid (CSF) leaks, composite free tissue transfer is a reliable and safe option. We report our experience with the latissimus dorsi/rib intercostal perforator myo-osseocutaneous free flap in the reconstruction of bony and soft tissue defects of the cranium and overlying scalp. The surgical technique, design, and outcomes of the latissimus dorsi/rib intercostal perforator myo-osseocutaneous free flap reconstruction in five patients with cranial defects between 2003 and 2007 were retrospectively evaluated. Patient characteristics, defect size, underlying cause, reconstructive details, and complications were analyzed. All patients (age 43 to 81) had composite defects ranging from 36 to 750 cm2 (mean size 230 cm2) for the bony component and from 16 to 400 cm2 (mean size 170 cm2) for the soft tissue defect. All patients had a history of prior or current infection of the affected area, and two patients had a CSF leak. Defects were due to malignancy and infection (n = 2), infiltrative cutaneous mucormycosis with osteomyelitis (n = 1), and hemorrhagic stroke requiring craniectomy (n = 2), complicated by infection and failed cranioplasty in one patient and continuous CSF leak in the other. The latissimus dorsi composite free flap consisting of skin, muscle, and vascularized rib can successfully cover large complex cranial defects, provide skeletal support, improve contour, and significantly enhance functional outcome with limited donor site morbidity.

Giant naevus, giant excision, eleg(i)ant closure? Reconstructive surgery with Integra Artificial Skin ® to treat giant congenital melanocytic naevi in children

The optimal surgical treatment of giant congenital melanocytic naevi remains a considerable challenge in reconstructive surgery. None of the currently available techniques is universally applicable. The goal of this pilot study was to test Integra Artificial Skin (Integra) in the surgical treatment of giant congenital melanocytic naevi. Between May 2000 and March 2004, Integra was used in 12 children (n=12; aged seven months to 11 years, mean 3.8 years). Giant congenital melanocytic naevi covered 1-12% of the total body surface area (mean 4.2%) located over the trunk in 50%, and over face and extremities in 25% each. In eight children, Integra implantation was primarily successful; in four patients a partial or complete removal and re-implantation was necessary due to complications. The final take rate of Integra ranged from 95-100%, except for one patient with a take rate of 30% (mean 93%). Second stage split-thickness skin grafting yielded take rates from 95-100% (mean 98%). Functional and cosmetic outcome was rated excellent in 58%, good in 25% and fair in 17% (follow-up six months to four years, mean 2.2 years). These results suggest that Integra is a new and valid method to successfully treat giant congenital melanocytic naevi in early childhood in a definitive manner and with high-quality results.

IFATS Collection: Human Adipose-Derived Stem Cells Seeded on a Silk Fibroin-Chitosan Scaffold Enhance Wound Repair in a Murine Soft Tissue Injury Model

Soft tissue loss presents an ongoing challenge in reconstructive surgery. Local stem cell application has recently been suggested as a possible novel therapy. In the present study we evaluated the potential of a silk fibroin-chitosan (SFCS) scaffold serving as a delivery vehicle for human adipose-derived stem cells (ASCs) in a murine soft tissue injury model. Green fluorescent protein (GFP)-labeled ASCs were seeded on SFCS scaffolds at a density of 1 x 10(5) ASCs per cm(2) for 48 hours and then suture-inlaid to a 6-mm, full-thickness skin defect in 6-week-old male athymic mice. Wound healing was tracked for 2 weeks by planimetry. Histology was evaluated at 2 and 4 weeks. Our data show that the extent of wound closure was significantly enhanced in the ASC-SFCS group versus SFCS and no-graft controls at postoperative day 8 (90% +/- 3% closure vs. 75% +/- 11% and 55% +/- 17%, respectively). Microvessel density at wound bed biopsy sites from 2 weeks postoperative was significantly higher in the ASC-SFCS group versus SFCS alone (7.5 +/- 1.1 vs. 5.1 +/- 1.0 vessels per high-power field). Engrafted stem cells were positive for the fibroblastic marker heat shock protein 47, smooth muscle actin, and von Willebrand factor at both 2 and 4 weeks. GFP-positive stem cells were also found to differentiate into epidermal epithelial cells at 4 weeks postoperative. In conclusion, human adipose-derived stem cells seeded on a silk fibroin-chitosan scaffold enhance wound healing and show differentiation into fibrovascular, endothelial, and epithelial components of restored tissue.

Distally based sural fasciomyocutaneous flap: Anatomic study and modified technique for complicated wounds of the lower third leg and weight bearing heel

The reconstruction of the distal third leg and weight-bearing heel, especially when complicated with infection and/or dead space, remains a challenge in reconstructive surgery. The distally based sural neurofasciomyocutaneous flap has been proved a valuable tool in repair of the soft tissue defects of those areas. In this report, we present the results of the anatomical study on vascular communication between the suprafascial sural neurovascular axis and the deep gastrocnemius muscle and a modified technique in clinical applications for reconstruction of the soft tissue defects in the distal lower leg and heel. Six lower limbs of fresh cadavers were injected with red gelatin and dissected. A constant vascular connection with average four musculo-fasciocutaneous perforators with diameter 0.2-0.5 mm was identified in the overlapping area between the suprafascial sural neurovascular axis and the deep gastrocnemius muscle. Based on these findings, a modified distally based sural neurofasciomyocutaneous flap including the distal gastrocnemius muscle component was designed and used for repairs of the soft tissue defects in the distal lower limb and plantar heel pad in six patients. The blood supplies of flaps comprised either the peroneal perforator and adipofascial pedicle or the peroneal perforator only. The average size of the fasciocutaneous flap was 51 cm(2), and the muscle component 17.7 cm(2). All flaps survived uneventfully. Our results suggest that this technical modification could provide wider range for applications of the distally based sural neurofasciomyocutaneous flap in repair of the soft tissue defects of the lower extremity and heel.

Nasal reconstruction: a challenge for plastic surgery.

Surgeons from a number of different specialties are now more commonly performing nasal reconstruction procedures to repair deformities resulting from trauma or tumor resection. Whenever a nasal reconstruction is performed, it is very important that the currently well-established plastic surgical techniques in this area should be correctly applied. Overview of the surgical techniques for nasal reconstruction applied to typical nasal defects, on the basis of a selective review of the literature. Any of the structurally important layers of the nose (skin, cartilaginous framework, inner lining) that are missing must be reconstructed. The current techniques follow the principle of esthetic reconstruction. Thorough patient counseling enables the patient to cope with temporally protracted treatment, to withstand the associated social and psychological stress, and to decide whether to undergo an autologous reconstruction or a prosthetic replacement. The operating surgeon must have a great deal of experience in nasal reconstruction. The surgeon must, therefore, be a specialist with a particular emphasis in this area.

Treatment of upper limb lymphedema with combination of liposuction, myocutaneous flap transfer, and lymph‐fascia grafting: A preliminary study

Treatment of obstructive extremity lymphedema remains a challenge in reconstructive surgery, since none of the varieties of procedures have been demonstrated a reliable resolution for the lymphedema. In this report, we present the preliminary results of treatment of severe upper extremity lymphedema with combined liposuction, latissimus myocutaneous flap transfer, and lymph-fascia grafting in 11 patients. All patients had histories of radical mastectomy, irradiation therapy for breast cancer, and frequent onsets of erysipelas. Postoperative measurements in an average of 26 months follow up showed that significant decrease of circumferences of the arms on all levels at surgery side were achieved. The onsets of erysipelas were also reduced. There was no chronic lymphedema found in the donor leg after harvest of the lymph-fascia graft. The results suggest the strategy of liposuction, latissimus myocutaneous flap transfer, and lymph-fascia grafting may provide a useful method for treatment of the chronic upper extremity lymphedema with severe axillary scar contracture.

Correction of the Title for “Fatal Outcome of Meningococcal Septicemia and Meningitis, Notwithstanding Severe Sequelae: An Alert for Clinical Practitioners and a Challenge for Plastic Surgery”

Correction of the Title for “Fatal Outcome of Meningococcal Septicemia and Meningitis, Notwithstanding Severe Sequelae: An Alert for Clinical Practitioners and a Challenge for Plastic Surgery”

Biocompatibility issues with modern implants in bone - a review for clinical orthopedics.

Skeletal defects may result from traumatic, infectious, congenital or neoplastic processes and are considered to be a challenge for reconstructive surgery. Although the autologous bone graft is still the “gold standard”, there is continuing demand for bone substitutes because of associated disadvantages, such as limited supply and potential donor side morbidity [1]. This is not only true for indications in orthopedic and craniomaxillofacial surgeries, but also in repairing endodontic defects and in dental implantology.Before clinical use all new bone substitute materials have to be validated for their osseoconductive and - depending on the composition of the material also –inductive ability, as well as for their long-term biocompatibility in bone. Serving this purpose various bone healing models to test osteocompatibility and inflammatory potential of a novel material on one hand and, on the other hand, non-healing osseous defects to assess the healing potential of a bone substitute material have been developed. Sometimes the use of more than one implantation site can be helpful to provide a wide range of information about a new material [2].Important markers for biocompatibility and inflammatory responses are the cell types appearing after the implantation of foreign material. There, especially the role of foreign body giant cells (FBGC) is discussed controversial in the pertinent literature, such that it is not clear whether their presence marks an incompatibility of the biomaterial, or whether it belongs to a normal degradation behavior of modern, resorbable biomaterials.This publication is highlighting the different views currently existing about the function of FBGC that appear in response to biomaterials at the implantation sites. A short overview of the general classes of biomaterials, where FBGC may appear as cellular response, is added for clarity, but may not be complete.

Does adipose tissue cultured with collagen matrix and preadipocytes give comparable results to the standard technique in plastic surgery?

Repairing contour defects is a challenge in plastic surgery. Different filling materials have been used with inadequate results and complications. The autologous fat transfer is the standard technique at the moment, but adipose tissue reserves are limited. The aim of our study was to compare in vivo on an animal model, preadipocytes cultured in a collagen scaffold versus adipose tissue transferred by the usual surgical technique. In order to compare adipocytes resulting from the differentiation of preadipocytes with those of purified adipose tissue, we implanted them in 10 nude mice. The preadipocytes were implanted using a collagen scaffold as intermediary and the adipose tissue following the plastic surgery protocol described by SR Coleman. After 8 weeks, tissue fragments were explanted and analysed after staining with HPS, Oil Red O and labelling with human anti-vimentin antibodies. The scaffold seeded with preadipocytes had the macroscopic appearance of adipose tissue with peripheral neovascularisation. The preadipocytes had been transformed into mature adipocytes. Purified adipose tissue also presented peripheral neovascularisation. Numerous mature adipocytes were found. There was an abundant murine extracellular matrix since anti-vimentin labelling was negative. This experimental study showed that adipose tissue engineering is feasible and gives comparable results to fat grafting. It allows a better understanding of the sequence of events following the transfer of adipose tissue. It provides not only volume but also undeniable stimulation, leading to significant thickening of the extracellular matrix.

Fatal Outcome of Meningococcal Septicemia and Meningitis, Notwithstanding Severe Sequelae: An Alert for Clinical Practitioners and a Challenge for Plastic Surgery

Fatal Outcome of Meningococcal Septicemia and Meningitis, Notwithstanding Severe Sequelae: An Alert for Clinical Practitioners and a Challenge for Plastic Surgery

Extracorporeal Shock Wave Enhanced Extended Skin Flap Tissue Survival via Increase of Topical Blood Perfusion and Associated with Suppression of Tissue Pro-Inflammation

Distal skin flap ischemic necrosis is a significant challenge in reconstructive surgery. This study assessed whether extracorporeal shock wave (ESW) treatment rescues compromised flap tissue by enhancing tissue perfusion and is associated with suppression of inflammatory response. This study used the dorsal skin random flap model in a rodent. Thirty-six male Sprague Dawley rats were divided into three groups. Group I, a control group, received no treatment. Group II was administrated 500 impulses of ESW treatment at 0.15 mJ/mm(2) as a single treatment immediately postoperatively. Group III received 500 impulses of ESW at 0.15 mJ/mm(2) applied immediately postoperatively and the day following surgery. Flap blood perfusion was detected by laser Doppler. Flap survival/necrosis area and histological staining of flap ischemia zone was performed on day 7 postoperatively. The tumor necrosis factor alpha, vascular endothelial growth factor, and proliferating cell nuclear antigen expression were evaluated with immunohistochemical staining. Experimental results indicated that the necrotic area of the flaps in Group II was significantly reduced compared with that in the control group (13 +/- 2.6% versus 42 +/- 5.7%, P < 0.01). There was small and insignificant reduction in the necrotic area in Group III compared with the controls. Flap tissue blood perfusion was significantly increased postoperatively in Group II. Histological staining indicated that ESW treatment substantially increased vascular endothelial growth factor and proliferating cell nuclear antigen expressions, reduced leukocyte infiltration, and suppression of tumor necrosis factor alpha expression in flap tissue ischemic zones in Group II compared with that in controls. Optimal dosage of ESW treatment has a positive effect in rescuing ischemic zone of flap by increasing tissue perfusion and is associated with suppressing inflammatory response.

Allotransplants vascularisés de tissus composites digitaux : anatomie chirurgicale du prélèvement et modulations morphologiques en fonction des pertes de substance

Microsurgery and human allotransplantation progress as well as the improvement of immunosuppressive drugs actually allow the development of the composite tissue allotransplantation. One of the latest challenges in plastic surgery is to restore the anatomic and functional structures using similar tissues. Composite tissue allotransplantation will probably reach this goal. Our work is to find new surgical techniques for the reconstruction of the osteotendinous apparatus of the long digits. In this paper, we will demonstrate the surgical technique to harvest the allotransplant and its modulation in the reconstruction of various digital defects.

Überexpression von β1-Integrin in oralen Keratinozyten korreliert mit deren hohen Proliferationskapazität

Large defects of the oral mucosa are still a major challenge in reconstructive surgery. For the development of oral mucosal grafts, successful enrichment of cells with a high proliferative potential is highly desirable. Therefore, the aim of this study was to separate two fractions of oral keratinocytes based on their affinity to collagen type IV. Oral keratinocytes were isolated from oral mucosa and separated into two fractions with different affinities to collagen type IV. Growth curves, Western blot analysis and immunohistochemical staining were used to detect differences between the two cell fractions. The cell fraction (RAC-IV) that adhered to collagen type IV within 20 min showed higher proliferative potential, significantly higher (P < 0.05) expression of integrin beta1 and fewer apoptotic cells. In particular, this fraction included small proliferating cells with the typical polygonal shape of oral keratinocytes, whereas the non-proliferating cells (RAC-IV-D) were irregularly shaped. Immunohistochemical staining showed only some apoptotic RAC-IV cells, whereas RAC-IV-D cells showed a significant increase of M30-positive cells. In addition, Western blotting revealed significantly higher (P < 0.05) expression of integrin beta1 in the RAC-IV fraction than in the RAC-IV-D fraction. Our results show that it is possible to enrich a fraction of highly proliferative oral keratinocytes by means of their high affinity to collagen type IV.

Microsurgical Fibular Flap for Pelvic Ring Reconstruction after Periacetabular Tumor Resection

Reconstruction after resection of tumor about the acetabulum represents a considerable challenge in reconstructive surgery. Between 1999 and 2003, three patients with periacetabular tumors underwent tumor resections (Ennecking type B) and pelvic ring reconstruction with microsurgical fibular flaps. Histological diagnosis showed osteosarcoma, giant cell tumor, and aneurysmoid bone cyst. All patients survived surgery without complications. The follow-up for patients ranged from 14 to 42 months. The average time for bone healing and full weight bearing was 13.6 weeks after surgery. In evaluations of the functional outcome using Enneking scoring system, two reached the score of excellent (>or= 23 points), and one reached the score of good (15 to 22 points). This report shows our experience in use of microsurgical fibular flaps for arthrodesis of the hip after periacetabular tumor resection, which restores the continuity of the pelvic ring with minimal shortening of the limb.

Selective blockade of endothelin-B receptor improves survival of critically perfused musculocutaneous flaps

Insufficient perfusion of distal flap areas, which may lead to partial necrosis, still represents a challenge in reconstructive surgery. In the process of microvascular and endothelial dysfunction, endothelins (ETs) and their receptors may play an important role. Therefore, the aim of the study was to investigate in a chronic in vivo model the effect of various ET-receptor antagonists in critically perfused flap tissue. A random pattern musculocutaneous flap was elevated in the back of 25 C57BL/6 mice and fixed into a dorsal skinfold chamber. Repetitive intravital fluorescence microscopy was performed over a 10-day observation period, assessing arteriolar diameter, arteriolar blood flow (aBF), functional capillary density (FCD), the area of tissue necrosis, and the development of newly formed blood vessels. ET-receptor blockers were administrated intraperitoneally 30 min before induction of ischemia, as well as daily during the subsequent 4-day period, including (1) BQ-123, a specific ET-A-receptor antagonist (ET-A = 1 mg/kg), (2) BQ-788, a selective ET-B-receptor antagonist (ET-B = 1 mg/kg), and (3) PD-142893, a nonselective ET-AB-receptor antagonist (ET-AB = 0.5 mg/kg). Animals receiving saline only served as controls (n = 7). Despite an increase in aBF during the 10-day observation period (day 1 = 1.92 +/- 0.29 nl/s; day 10 = 4.70 +/- 1.64 nl/s), the flaps of saline-treated controls showed a distinct decrease in FCD (94 +/- 12 cm/cm(2)). This perfusion failure resulted in flap necrosis of 52 +/- 3%. Selective blockade of the ET-B receptor caused a further increase in aBF already at day 1 (2.97 +/- 0.42 nl/s), which persisted during the following 10-day observation period (day 10 = 5.74 +/- 0.69 nl/s). Accordingly, adequate FCD could be maintained (day 10 = 215 +/- 8 cm/cm(2); p < 0.05 vs control), resulting in a significant reduction in flap necrosis (day 10 = 25 +/- 4%; p < 0,05). In contrast, neither selective blockade of the ET-A receptor nor nonselective ET-A- and ET-B-receptor blockade were able to significantly affect aBF when compared to controls (day 1 = ET-A = 1.39 +/- 0.10 nl/s; ET-AB = 1.53 +/- 0.80 nl/s; n.s.). Accordingly, flap necrosis after ET-A- and ET-AB-receptor inhibition did not differ from that of controls (day 10 = ET-A: 46 +/- 10%; ET-AB = 51 +/- 7%). Our data show that only selective ET-B-receptor inhibition is capable of maintaining nutritive perfusion and, hence, reducing necrosis in critically perfused flap tissue. Accordingly, administration of ET-B-receptor antagonists may be considered in the treatment of critically perfused flaps.