Ideal suturing technique for robot-assisted microsurgical anastomoses.

The development of novel robotic devices specifically designed for open microsurgery leads to increasing applications in reconstructive procedures. While initial studies revealed improved precision and surgical ergonomics upon robotic assistance, surgical time was consistently observed to be increased. This study compares two robotic suturing techniques using the Symani Surgical System and RoboticScope in a preclinical setting, to further leverage the benefits of novel robotic devices in microsurgery. Six experienced microsurgeons performed three microvascular anastomoses with a "steady-thread" suturing technique and a "switch-thread" technique on 1.0-mm-diameter artificial silicone vessels. Time for anastomosis and participant's satisfaction with the techniques and robotic setup were recorded. Anastomosis quality and microsurgical skills were assessed using the Anastomosis Lapse Index and Structured Assessment of Microsurgery Skills. Lastly, technical error messages and thread ruptures were quantified. Knot tying was significantly faster and evaluated significantly better by participants using the steady-thread technique (4.11 ± 0.85 vs. 6.40 ± 1.83 min per anastomosis). Moreover, microsurgical skills were rated significantly better using this technique, while both techniques consistently led to high levels of anastomosis quality (2.61 ± 1.21 vs. 3.0 ± 1.29 errors per anastomosis). In contrast, the switch-thread technique was associated with more technical error messages in total (14 vs. 12) and twice as many unintended thread ruptures per anastomosis (1.0 ± 0.88 vs. 0.5 ± 0.69). This study provides evidence for the enhanced performance of a steady-thread suturing technique, which is suggested to be applied upon robot-assisted microsurgical procedures for optimized efficiency.

Psychological well-being as a motive for and result of post-bariatric body contouring procedures.

Objective: This study investigates whether psychological well-being in post-bariatric patients seeking body contouring procedures differs from those who do not seek body contouring procedures, those who have already undergone body contouring procedures, and those who are unsure about body contouring procedures. Methods: An anonymous, nonrandomized, cross-sectional survey study was designed. Psychological well-being of four groups of post-bariatric-patients (undergone body contouring procedures, seeking body contouring procedures, not seeking body contouring procedures, unsure about body contouring procedures) were compared. Results: A total of 345 patients were included in this study. No significant difference between patients seeking body contouring procedures and those not seeking body contouring procedures was found with regard to depressive symptoms, self-esteem, and body image. Patients who had already undergone body contouring procedures scored lower on depressive symptoms (p = 0.035) and reported feeling more attractive (p < 0.001) and less insecure (p = 0.030) than patients who had not yet undergone body contouring procedures but sought it. Satisfaction with the result of the body contouring procedures was associated with lower depression levels (p < 0.001), higher self-esteem (p < 0.001) and a more positive body-image (p < 0.001). Conclusions: Depressive symptoms or low self-esteem are not motivational factors for post-bariatric patients to seek body contouring procedures. Body contouring procedures are associated with improvement in psychological well-being in post-bariatric patients. Patients' satisfaction with the result of the body contouring procedures is significantly associated with positive psychological well-being.

Breast Reconstruction with DIEP Flap: The Learning Curve at a Breast Reconstruction Center and a Single-Surgeon Study.

Although microsurgical breast reconstruction represents a very interesting and rewarding field of plastic surgery, appropriate microsurgical training is not possible in every plastic surgery department. In this retrospective study, we present the learning curve of our plastic surgery department as a whole and of a single microsurgeon assessing breast reconstruction procedures with a deep inferior epigastric artery perforator (DIEP) flap between July 2018 and June 2021. The present study included 115 patients and 161 flaps. Cases were stratified into single DIEP/double DIEP groups and into early and late groups based on the flap order. Surgery times and postoperative complications were analyzed. Regarding the institution, the length of hospital stay was lower in the late group than in the early group (single 7.1 ± 1.8 vs. 6.3 ± 1.5 days, p = 0.019; double 8.5 ± 3.8 vs. 6.6 ± 1.4 days, p = 0.043). Apart from that, no statistically significant differences were found between the start and end of our study. In terms of the single surgeon, there was a significant improvement in the total surgery time (single 296.0 ± 78.7 vs. 227.5 ± 54.7 min, p = 0.018; double 448.0 ± 85.6 vs. 341.2 ± 43.1 min, p = 0.008), flap ischemia time (53.6 ± 15.1 vs. 40.9 ± 9.5 min, p = 0.007) and length of stay among the compared groups. There was no significant difference in flap loss rate or other complications between the early and late groups. Further performance of surgeries seemed to improve the surgeon's skills as well as the overall experience of the medical institution.

The Influence of Obesity on Melanoma and Sentinel Lymph Node Diagnosis: A Retrospective Monocentric Study in 1001 Patients.

(1) Background: While obesity is a known independent risk factor in the development of melanoma, there is no consensus on its influence on melanoma prognosis. (2) Methods: In a monocentric retrospective study, data was collected from patients who underwent sentinel lymph node (SLN) biopsy for stage IB-IIC melanoma between 2013 and 2018. Patients were divided into groups according to their body mass index (BMI). The association between BMI and melanoma features, as well as the risk factors for metastases in SLN were examined. (3) Results: Of the 1001 patients, 336 had normal weight (BMI < 25), 402 were overweight (BMI >= 25 and <30), 173 obese (BMI >= 30 and <35) and 90 extremely obese (BMI >= 35). Overweightness and obesity were associated with higher tumor thicknesses at time of diagnosis. Ulceration was not influenced by the patient's weight. Metastases in sentinel lymph node was almost twice more likely in extremely obese patients than in normal weight patients. Independent risk factors for metastases in SLN in our study were tumor thickness, ulceration, and BMI > 35. (4) Conclusions: This is the first study to show higher metastases rates in high-BMI patients with melanoma, raising important questions regarding the screening and treatment of this specific patient population.

Tolerance Induction in Vascularized Composite Allotransplantation-A Brief Review of Preclinical Models.

Pre-clinical studies are an obligatory tool to develop and translate novel therapeutic strategies into clinical practice. Acute and chronic rejection mediated by the recipient's immune system remains an important limiting factor for the (long-term) survival of vascularized composite allografts (VCA). Furthermore, high intensity immunosuppressive (IS) protocols are needed to mitigate the immediate and long-term effects of rejection. These IS regiments can have significant side-effects such as predisposing transplant recipients to infections, organ dysfunction and malignancies. To overcome these problems, tolerance induction has been proposed as one strategy to reduce the intensity of IS protocols and to thereby mitigate long-term effects of allograft rejection. In this review article, we provide an overview about animal models and strategies that have been used to induce tolerance. The induction of donor-specific tolerance was achieved in preclinical animal models and clinical translation may help improve short and long-term outcomes in VCAs in the future.

Transgenic skin biomechanical properties following first lifesaving epidermal regeneration using combined gene and cell therapy.

BACKGROUND: In 2017, we reported the first life-saving regeneration of virtually an entire epidermis by combined gene and stem cell therapy. Recently, we demonstrated excellent long-term stability of this transgenic epidermis. Skin quality in this experimental approach and its potential application in other conditions were elucidated here regarding long-term outcomes of biomechanical properties. PATIENTS AND METHODS: Analysis of biomechanical properties including skin elasticity, anisotropy and friction was performed on multiple body sites 24, 36 and 60 months following transplantation. Firstly, the sites were matched against and compared to remaining stable non-transgenic areas as well as to a control group of 13 healthy subjects. Parameters for skin elasticity, deformation and friction were assessed non-invasively. RESULTS: Biomechanical properties of the transgenic epidermis showed encouraging results in comparison to both the remaining stable non-transgenic skin as well as healthy controls. Skin elasticity was comparable to the controls. Skin friction showed some decrease in both transgenic and non-transgenic areas as compared to the controls. CONCLUSIONS: The excellent functional outcomes of the transgenic epidermis demonstrate stable long-term results of this novel combined gene and stem cell therapy for epidermal regeneration. Thus, other applications for this technology, such as treatment of specific burns, should be explored.

Robotic-Assisted Microsurgery and Its Future in Plastic Surgery.

Within the last 20 years, robotic-assisted surgeries have been implemented as routine procedures in many surgical fields, except in plastic surgery. Although several case series report promising results, technical and economic aspects have prevented its translation into clinical routine. This review is based on a PubMed and Google Scholar database search, including case reports, case series, clinical and preclinical trials, as well as patents. Past, recent approaches, ongoing patents, as well as eight specific systems for robotic-assisted microsurgery and their potential to be translated into a clinical routine, are described. They may lay the ground for a novel field within plastic surgery. This review provides an overview of the emerging technologies and clinical and preclinical studies and discusses the potential of robotic assistance in the field of plastic surgery.

Free flap breast reconstruction using a novel robotic microscope.

INTRODUCTION: Robotic-assisted surgery (RAS) has evolved over the past decades. Currently, novel robotic systems for microsurgery are being launched onto the European market. This novel microscope (RoboticScope®, BHS, Innsbruck, Austria) is a high-definition camera system, connected to an augmented reality headset, projecting a clear image with high magnification in front of the surgeon's eyes. Motion tracking translates the surgeon's head movements onto the system via a multi-axis robotic arm. We report the first use of the robotic microscope for autologous breast reconstruction in humans. METHODS: In May 2020, ten autologous breast reconstructions were performed by our Team. Five reconstructions (three PAP flaps, one bilateral DIEP flap) were conducted with the robotic microscope and matched to five reconstructions using a conventional microscope. We compared ischaemia times, times for arterial and venous anastomosis, and complications. RESULTS: All procedures were performed successfully and safely. Overall time for anastomosis was 31 min (+/- 7 min) in the robotic group and 25 min (+/- 7 min, p = 0.30) in the control group. Flap ischaemia was 54 min (+/- 8 min) in the robotic group and 52 min (+/- 22 min, p = 0.87) in the control group. No intraoperative complications such as venous thrombosis or arterial embolism occurred. CONCLUSION: Robotic microscopes provide the technology to combine flexibility to choose different angles during pedicle preparation and improve the stationary procedure of vessel anastomosis. Novel robotic systems tailored towards refinement in microsurgery hold great potential for implementation in Plastic Surgery procedures.

A chronic rejection model and potential biomarkers for vascularized composite allotransplantation.

BACKGROUND: Chronic rejection remains the Achilles heel in vascularized composite allotransplantation. Animal models to specifically study chronic rejection in vascularized composite allotransplantation do not exist so far. However, there are established rat models to study chronic rejection in solid organ transplantation such as allogeneic transplantation between the rat strains Lewis and Fischer344. Thus, we initiated this study to investigate the applicability of hindlimb transplantation between these strains to imitate chronic rejection in vascularized composite allotransplantation and identify potential markers. METHODS: Allogeneic hindlimb transplantation were performed between Lewis (recipient) and Fischer344 (donor) rats with either constant immunosuppression or a high dose immunosuppressive bolus only in case of acute skin rejections. Histology, immunohistochemistry, microarray and qPCR analysis were used to detect changes in skin and muscle at postoperative day 100. RESULTS: We were able to demonstrate significant intimal proliferation, infiltration of CD68 and CD4 positive cells, up-regulation of inflammatory cytokines and initiation of muscular fibrosis in the chronic rejection group. Microarray analysis and subsequent qPCR identified CXC ligands 9-11 as potential markers of chronic rejection. CONCLUSIONS: The Fischer344 to Lewis hindlimb transplantation model may represent a new option to study chronic rejection in vascularized composite allotransplantation in an experimental setting. CXC ligands 9-11 deserve further research to investigate their role as chronic rejection markers.

Extracorporeal Perfusion in Vascularized Composite Allotransplantation: Current Concepts and Future Prospects.

Severe injuries of the face and limbs remain a major challenge in today's reconstructive surgery. Vascularized composite allotransplantation (VCA) has emerged as a promising approach to restore these defects. Yet, there are major obstacles preventing VCA from broad clinical application. Two key restrictions are (1) the graft's limited possible ischemia time, keeping the potential donor radius extremely small, and (2) the graft's immunogenicity, making extensive lifelong monitoring and immunosuppressive treatment mandatory. Machine perfusion systems have demonstrated clinical success addressing these issues in solid organ transplantation by extending possible ischemia times and decreasing immunogenicity. Despite many recent promising preclinical trials, machine perfusion has not yet been utilized in clinical VCA. This review presents latest perfusion strategies in clinical solid organ transplantation and experimental VCA in light of the specific requirements by the vascularized composite allograft's unique tissue composition. It discusses optimal settings for temperature, oxygenation, and flow types, as well as perfusion solutions and the most promising additives. Moreover, it highlights the implications for the utility of VCA as therapeutic measure in plastic surgery, if machine perfusion can be successfully introduced in a clinical setting.

Acellular Hypothermic Extracorporeal Perfusion Extends Allowable Ischemia Time in a Porcine Whole Limb Replantation Model.

BACKGROUND: One of the major challenges in traumatic amputation is the need to keep ischemia time brief (4 to 6 hours) to avoid ischemic damage and enable successful replantation. The current inability to meet this challenge often leads to traumatic limb loss, which has a considerable detrimental impact on the quality of life of patients. METHODS: The authors' team built a portable extracorporeal membrane oxygenator device for the perfusion of amputated extremities with oxygenated acellular solution under controlled parameters. The authors amputated forelimbs of Yorkshire pigs, perfused them ex vivo with acellular Perfadex solution for 12 hours at 10°C in their device, and subsequently replanted them into the host animal. The authors used limbs stored on ice slurry for 4 hours before replantation as their control group. RESULTS: Clinical observation and histopathologic evaluation both demonstrated that there was less morbidity and less tissue damage to the cells during preservation and after replantation in the perfusion group compared with the standard of care. Significant differences in blood markers of muscle damage and tissue cytokine levels underscored these findings. CONCLUSIONS: The authors demonstrated the feasibility and superiority of ex vivo hypothermic oxygenated machine perfusion for preservation of amputated limbs over conventional static cold storage and herewith a substantial extension of the allowable ischemia time for replantation after traumatic amputation. This approach could also be applied to the field of transplantation, expanding the potential pool of viable donor vascularized composite allografts.

A Mobile Extracorporeal Extremity Salvage System for Replantation and Transplantation.

BACKGROUND: Traumatic amputation is the second leading cause of limb loss in the United States. The preferred treatment is salvage and replantation of the amputated limb, whenever possible, and allotransplantation is a novel procedure whereby healthy limbs are procured from deceased organ donors and transplanted into the amputee recipient. A major restriction for both procedures is the irrecoverable muscle damage occurring due to ischemia. We investigated the feasibility of using a novel lightweight, mobile perfusion device specifically designed to perfuse amputated porcine limbs with an acellular perfusion solution to delay ischemic muscle damage prior to transplantation or replantation. METHODS: Bilateral hind limbs of Yorkshire pigs were amputated; one of the limbs was preserved by perfusion in the mobile perfusion device, and the other by storage in ice slurry for 12 hours. RESULTS: Five sets of bilateral limbs were preserved as described previously. A defined pressure of 30 mm Hg was reliably maintained in the arterial system without loss of flow. Comparison of the perfusate composition before and after limb passage revealed significant differences. Muscle biopsies showed a consistent progression of clusters of hypoxic cells in the control limbs with time. Similar changes could not be observed in the perfused tissue. CONCLUSIONS: We have designed and built a small, mobile perfusion device that is operational and that more closely mimics the normal physiological environment when compared with the current standard of preservation in ice slurry. This project may have far-reaching implications for the treatment of limb loss through replantation and transplantation.

Pixel Grafting: An Evolution of Mincing for Transplantation of Full-Thickness Wounds.

BACKGROUND: Split-thickness skin grafting is the gold standard for treatment of major skin loss. This technique is limited by donor-site availability in large burn injuries. With micrografting, a technique where split-thickness skin graft is minced into 0.8 × 0.8-mm pieces, the authors have demonstrated an expansion ratio of 1:100 and healing comparable to that achieved with split-thickness skin grafting. METHODS: In this study, the authors explore the regenerative potential of a skin graft by cutting split-thickness skin grafts to pixel size (0.3 × 0.3 mm) grafts. Wound healing was studied in full-thickness wounds in a porcine model by creating an incubator-like microenvironment using polyurethane wound chambers. Multiple wound healing parameters were used to study the outcome of pixel grafting and compare it to micrografting and nontransplanted wounds. RESULTS: The authors' results show that 0.3 × 0.3-mm pixel grafts remain viable and contribute to skin regeneration. The pixel graft-transplanted wounds demonstrated a faster reepithelialization rate, decreased wound contraction, and increased mechanical stability compared with nontransplanted wounds. The reepithelialization rates of the wounds were significantly increased with pixel grafting at day 6 after wounding compared with micrografting. Among the other wound healing parameters, there were no significant differences between wounds transplanted with pixel grafts and micrografts. CONCLUSIONS: Pixel grafting technique would address the most commonly encountered limitations of the split-thickness skin graft with the possibility of an even larger expansion ratio than micrografting. This technique is simple and fast and can be conducted in the operating room or in the clinic.

Facial restoration by transplantation: the Brigham and Women's face transplant experience.

Since 2009, the face transplant team at Brigham and Women's Hospital in Boston has performed 6 successful partial and full facial transplantations on carefully selected patients. The development of these techniques has led to a new era in facial reconstruction which now more correctly can be described as facial restoration. Besides the obvious facts of giving someone with a missing or severely disfigured face a new appearance, facial restoration has led to many other interesting observations in terms of immunologic models, airway functionality, sensory recovery and cerebral cortical functioning. In this article, we present an overview of our experience, and where we are today-also presenting some of the interesting avenues that have opened and will lead us further in the daunting experience of facial allotransplantation.