establishment-robust-reproducible-model-radiation-induced-skin-muscle

Establishment of a Robust and Reproducible Model of Radiation-Induced Skin and Muscle Fibrosis

Radiation-induced skin fibrosis (RISF) can result from a plethora of scenarios including cancer therapy, accidental exposure, or acts of terrorism. ...

University of Pittsburgh

Combination of tissue expansion and perforator flaps broadened the reconstructive options in burn cases with wide scar contractures. We report a case of total aesthetic subunit reconstruction of the anterior abdominal skin using a pre-expanded pedicled anterolateral thigh (ALT) perforator flap in a patient with postburn contractures. Seventeen-year-old girl had a history of scalding burn to the anterior abdomen, resulting in tight contractures inhibiting her mobility. After an expansion period of 6 months, the flap of 27 × 30 cm was elevated at the suprafascial plane and tunneled to the anterior abdomen. The flap was used to resurface the defect from xyphoid process down to the mons pubis and bilaterally at linea semilunaris. Postoperative course was uneventful. A good quality aesthetic and functional reconstruction was achieved at the 10-year follow-up. Pre-expanded pedicled ALT flaps may be considered as an option in extensive scarring requiring large amounts of tissue.

Total aesthetic subunit reconstruction of the burned anterior abdomen using pre-expanded pedicled anterolateral thigh flap-A case report.

Burn contractures of the anterior neck result in severe functional and aesthetic deformities. The release of wide contractures leads to defects that cannot be closed with local flaps. In these cases, tissue expansion of local tissues may be a solution. However, when local tissues are also burned or inadequate, microsurgical free tissue transfer may be necessary. In order to increase the surface are of the transferred flap, pre-expansion of the donor site can be combined with the procedure. Five patients with burn contractures of the anterior neck were treated using pre-expanded free anterolateral thigh (ALT) perforator flaps. The anterolateral thigh was dissected on top of the fascia lata in an avascular plane. The borders of the dissection were kept 2 cm lateral to the pre-identified perforators. A 1000cc rectangular tissue expander was placed. The time of expansion ranged from 4-11 months with a final over expanded volume of 1200cc. The defect sizes ranged from 10 × 21 cm to 20 × 27 cm. There were either one or two perforators included in the flaps. All flaps survived completely with good functional and aesthetic outcomes. Donor areas were closed primarily in one patient and with various amounts of skin grafts in five patients. Overall, pre-expansion decreased the amount of total skin grafted area in the donor site. Pre-expanded ALT perforator flap can be a good option in extensive burns with wide contractures where the regional donor areas are also affected. This technique has several advantages: 1) large flaps can be safely harvested, 2) the expanded skin thins out making it more aesthetically appropriate to resurface superficial defects, 3) expansion period of the thigh is well tolerated by the patients, 4) two teams can work simultaneously, decreasing the operating time, 5) the donor area can be closed either primarily or with minimal skin graft application, and 6) there is no functional loss in the donor area and the donor scar stays under the clothes.

Reconstruction of burn contractures of the anterior neck with pre-expanded free anterolateral thigh flaps.

Surgeons have preferential ways of performing venous anastomosis in head and neck microsurgery. However, controversies exist regarding the superiority of each method. This study aims to determine the effects of these variables on the rates of thrombosis and flap failure, and propose an algorithm to be used as a facilitator in the decision-making process. A total of 208 microsurgical reconstructions on 199 patients from a single surgeon's data were evaluated. Selection of recipient vein (superficial vs. deep), style of anastomosis (end-to-end vs. end-to-side), number of outflows (one vs. two) and technique of anastomosis (hand-sewn vs. coupler) were compared. Selection was done according to the pre- and intraoperative plan, as well as, surgeon's clinical judgement. Outcomes were determined as rates of venous thrombosis and flap failure. Five patients (2.4%) had venous problems, leading to two partial and three total flap failures. Selection of the recipient vein, style and number of outflows did not affect the outcomes, whereas coupler use decreased the rates of venous thrombosis and flap failure (p=0.008). Although it is difficult to set dogmatic criteria to achieve consistent outcomes, coupler use in this study prevented flap failure. An algorithmic approach was proposed with the results of the data and literature to increase the success in microsurgical anastomosis. Surgeons should use algorithms and sound judgement with adherence to microsurgical principles to obtain the best results for each patient.

Analysis of Selection of Recipient Vein, Number of Outflows, Style and Technique in Head and Neck Venous Anastomosis and a Proposed Algorithm.

Reconstruction of breast burns are challenging, as it includes both functional and aesthetic components. Transverse myocutaneous gracilis (TMG) flap has been used for postmastectomy breast reconstruction in the absence of abdominal donor site availability. Use of this flap for the breast burns is limited. A 32-year-old female sustained 54% second and third degree burns resulting with bilateral total breast loss. Anterior and posterior thorax, upper and mid abdomen, neck, shoulders, and bilateral upper extremities were also involved. Inner medial thighs had an ample amount of tissue and had never been used as donor sites. The left TMG (28 × 12 cm, 1,413 g) was used for right, and the right TMG (30 × 14 cm, 1,635 g) was used for the left breast, 3 months apart. The contracture on the chest wall was completely excised. Venous anastomosis to the venae commitantes was performed using a 2.5 mm coupler, followed by an end-to-end arterial anastomosis to the internal mammary artery. Flaps were inset in a fashion so that the inferior part became the inframammary fold, and the anterior and posterior wings were joined in the upper pole, creating a conical shape. Minimal wound dehiscence in the postoperative course healed with dressing changes and both flaps survived completely. Nipple reconstruction and areolar tattooing was performed. The patient was very happy with the outcome at seventh year follow-up. TMG may be a valuable option even in bilateral cases of microsurgical autologous free tissue transfer for total aesthetic reconstruction of postburn breast loss.

Total aesthetic reconstruction of postburn bilateral breast loss using transverse myocutaneous gracilis free flaps: A case report and literature review.

Injury to the facial nerve can occur after different etiologies and range from simple transection of the branches to varying degrees of segmental loss. Management depends on the extent of injury and options include primary repair for simple transections and using autografts, allografts, or conduits for larger gaps. Tissue engineering plays an important role to create artificial materials that are able to mimic the nerve itself without extra morbidity in the patients. The use of neurotrophic factors or stem cells inside the conduits or around the repair site is being increasingly studied to enhance neural recovery to a greater extent. Preclinical studies remain the hallmark for development of these novel approaches and translation into clinical practice. This review will focus on preclinical models of repair after facial nerve injury to help researchers establish an appropriate model to quantify recovery and analyze functional outcomes. Different bioengineered materials, including conduits and nerve grafts, will be discussed based on the experimental animals that were used and the defects introduced. Future directions to extend the applications of processed nerve allografts, bioengineered conduits, and cues inside the conduits to induce neural recovery after facial nerve injury will be highlighted. Impact statement Recovery after facial nerve injury is a complex process, which involves different management options such as primary repair or the use of nerve grafts or conduits. Various tissue-engineered approaches are increasingly studied on preclinical models with limited, but promising, translation to the clinical setting. Herein, preclinical models focusing on different recovery methods after facial nerve injury are comprehensively reviewed based on the experimental animals used. The review provides key insights into current developments and future directions on this highly relevant topic to help researchers further expand the field of tissue engineering and facial nerve recovery.

Facial Nerve Repair: Bioengineering Approaches in Preclinical Models.

Complication rates after spinal surgery are high, in part because of surgical advancements that have made procedures available to a broader range of medically complicated patients. The high rates of infection, hematoma, and dehiscence resulting in open wounds after spinal surgery often warrant plastic surgery involvement. In this study, we aim to examine the effects of preoperative and operative risk factors on complication rates, reoperation rates, and hospital length of stay after flap reconstruction of spinal defects.

Flap Closure of Spinal Defects in High-Risk Patients: A 10-Year Institutional Experience.

Large midline sacral defects are reconstructive challenges. Superior gluteal artery perforator (SGAP) flap provides enough tissue and versatility to cover large defects; however, a single flap may be insufficient. We present a technique to cover large defects using single SGAP flaps.

A Single Superior Gluteal Artery Perforator Flap in Reconstruction of Large Midline Sacral Defects: A Method for Practical Harvest and Safe Closure.

Lateral circumflex femoral artery (LCFA) system is one of the most versatile donor sites in the body. We present our experience with pedicled flaps from the LCFA system, including different components for a wide variety of etiologies and locations. Twenty-three consecutive pedicled flaps were performed on 22 patients (10 females and 12 males; age 4-71 years) between 2007 and 2015 by a single surgeon. Flap size, type, and composition were tailored according to the requirements of the defects, including (1) location; (2) surface area; (3) depth; (4) number of defects; (5) presence of exposed critical structures; (6) presence of exposed foreign bodies; (7) prior use of other options; (8) history of radiation; and (9) other comorbidities. Defect locations were 10 abdominal wall (including groin and pubis), 9 ischio-gluteo-trochanteric and 4 perineal. Defect sizes ranged from 6 × 6 to 30 × 35 cm. Maximum depth of wounds ranged between 7 and 18 cm. The flap sizes ranged from 9 × 6 to 38 × 20 cm. Two flaps were fasciocutaneous perforator, 4 were myocutaneous with "muscle sparing" vastus lateralis, 10 were myocutaneous with "segmental" vastus lateralis, 5 were myocutaneous "tri-muscle," 1 was "tri-muscle," and 1 was rectus femoris only. Donor sites were closed primarily in 20 cases and with split thickness skin grafting in 3 cases. All flaps survived completely without any partial loss or congestion. Pedicled flaps from the LCFA system can be tailored individually for a wide variety of etiologies and locations. Muscles can be harvested and used as "muscle sparing," "segmental," and "tri-muscle" to accommodate the requirements of the defects.

Individually tailored approach to reconstruction of complex defects using versatility of the lateral circumflex femoral artery system-based pedicled flaps.

 Venous thromboembolism (VTE) is a serious complication, particularly in cancer patients undergoing free flap reconstruction. Subcutaneous enoxaparin is the conventional prophylaxis for VTE prevention, and serum anti-factor Xa (afXa) levels are being increasingly used to monitor enoxaparin activity. In this study, free flap patients receiving standard enoxaparin prophylaxis were prospectively followed to investigate postoperative afXa levels and 90-day VTE and bleeding-related complications.

Standard Fixed Enoxaparin Dosing for Venous Thromboembolism Prophylaxis Leads to Low Peak Anti-Factor Xa Levels in Both Head and Neck and Breast Free Flap Patients.

Article	Year
Total aesthetic subunit reconstruction of the burned anterior abdomen using pre-expanded pedicled anterolateral thigh flap-A case report. Microsurgery\| PubMed ID: 31621940	2019
Reconstruction of burn contractures of the anterior neck with pre-expanded free anterolateral thigh flaps. Injury\| PubMed ID: 32122624	2020
Analysis of Selection of Recipient Vein, Number of Outflows, Style and Technique in Head and Neck Venous Anastomosis and a Proposed Algorithm. Journal of plastic, reconstructive & aesthetic surgery : JPRAS\| PubMed ID: 32571686	2020
Total aesthetic reconstruction of postburn bilateral breast loss using transverse myocutaneous gracilis free flaps: A case report and literature review. Microsurgery\| PubMed ID: 32749747	2020
Facial Nerve Repair: Bioengineering Approaches in Preclinical Models. Tissue engineering. Part B, Reviews\| PubMed ID: 33632013	2022
Flap Closure of Spinal Defects in High-Risk Patients: A 10-Year Institutional Experience. Annals of plastic surgery\| PubMed ID: 33883433	2021
A Single Superior Gluteal Artery Perforator Flap in Reconstruction of Large Midline Sacral Defects: A Method for Practical Harvest and Safe Closure. Annals of plastic surgery\| PubMed ID: 34139742	2022
Individually tailored approach to reconstruction of complex defects using versatility of the lateral circumflex femoral artery system-based pedicled flaps. Journal of plastic, reconstructive & aesthetic surgery : JPRAS\| PubMed ID: 34645586	2022
Standard Fixed Enoxaparin Dosing for Venous Thromboembolism Prophylaxis Leads to Low Peak Anti-Factor Xa Levels in Both Head and Neck and Breast Free Flap Patients. Journal of reconstructive microsurgery\| PubMed ID: 35714620	2022

Fuat Baris Bengur

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