Emodin activates autophagy to suppress oxidative stress and pyroptosis via mTOR-ULK1 signaling pathway and promotes multi-territory perforator flap survival.

BACKGROUND: Multi-territory perforator flap reconstruction has been proven effective in treating large skin and soft tissue defects in clinical settings. However, in view of that the multi-territory perforator flap is prone to partial postoperative necrosis, increasing its survival is the key to the success of reconstruction. In this study, we aimed to clarify the effect of emodin on multi-territory perforator flap survival. METHODS: Flap survival was assessed by viability area analysis, infrared laser imaging detector, HE staining, immunohistochemistry, and angiography. Western blotting, immunofluorescence assays, and real-time fluorescent quantitative PCR were performed to detect the indicators of oxidative stress, pyroptosis and autophagy. RESULTS: After emodin treatment, the multi-territory perforator flap showed a significantly increased survival rate, which was shown to be closely related to the inhibition of oxidative stress and pyroptosis and enhanced autophagy. Meanwhile, the use of autophagy inhibitor 3 MA was found to reverse the inhibitory effects of emodin on oxidative stress and pyroptosis and weaken the improving effect of emodin on flap survival, suggesting that autophagy plays a critical role in emodin-treated flaps. Interestingly, our mechanistic investigations revealed that the positive effect of emodin on multi-territory perforator flap was attributed to the mTOR-ULK1 signaling pathway activation. CONCLUSIONS: Emodin can inhibit oxidative stress and pyroptosis by activating autophagy via the mTOR-ULK1 pathway, thereby improving the multi-territory perforator flap survival.

Simultaneous Co-surgeon Deep Inferior Epigastric Perforator (DIEP) Flap Breast Reconstructions: Feasibility and Clinical Outcomes.

BACKGROUND: A co-surgeon model is known to be favorable in microvascular breast reconstruction, but simultaneous co-surgeon deep inferior epigastric perforator (DIEP) flap cases have not been well-studied. The authors hypothesize that performing two simultaneous co-surgeon bilateral DIEP flap reconstructions results in non-inferior clinical outcomes and may improve patient access to care. METHODS: A single-institution, retrospective cohort study was performed utilizing record review to identify all cases of co-surgeon free-flap breast reconstructions over a 38-month period. Patients who underwent simultaneous bilateral DIEP flap breast reconstructions with the same two co-surgeons were identified. The control group consisted of subjects who underwent non-simultaneous reconstruction by the same co-surgeons within the same, preceding, or following month of those in the study group. Primary outcome variables were 90-day postoperative complications, while secondary outcomes were operating time, ischemia time, and length of stay. Descriptive statistics, univariate and multivariable regression analyses were performed. RESULTS: Overall, 137 subjects were identified and 64 met the inclusion criteria (n = 28 study, n = 36 control). There were no statistically significant differences between groups in body mass index, radiation, trainee experience, flap perforator number, immediate/delayed reconstruction, or length of stay. There were also no statistically significant differences in complications, including flap loss, anastomosis revision, take-back to the operating room, or re-admission. Operative time was longer in the simultaneous DIEP group (540.5 vs. 443.5 min, p < 0.01), but ischemia time was shorter in the simultaneous group (64.0 vs. 80.5 min, p < 0.01). CONCLUSIONS: A simultaneous co-surgeon approach to bilateral DIEP flap reconstruction may improve access to care and does not result in a higher complication rate compared with non-simultaneous bilateral DIEP flaps.

Strategically shifting paradigms: the new era of DIEP flaps with minimally invasive mastectomy: a retrospective cross-sectional study.

BACKGROUND: The free deep inferior epigastric artery perforator (DIEP) flap is the gold standard in autologous breast reconstruction. Asian patients often present with a smaller body mass index with relatively insufficient tissue. To restore appropriate symmetry, a larger flap inset ratio must be transferred. Supercharging of the second vein or inclusion of bilateral pedicle is commonly required. Current paradigm shifts in mastectomy has also resulted in more minimally invasive surgeries (MIS) espousing smaller lateral incisions, leading to a significant change in available recipient vessels. This study aimed to demonstrate our experience in changing strategies of DIEP flaps following the evolution of mastectomy techniques. METHODS: Between October 2008 and March 2022, retrospective data was gathered for 278 patients who underwent breast reconstruction surgery utilizing DIEP flaps by a single plastic surgeon. These patients were divided into two distinct groups based on their operation dates, with November 2018 marking a pivotal moment when the first MIS, including endoscopic-assisted and robot-assisted mastectomy, was introduced. RESULTS: A total of 278 patients were included. Bipedicle vessel utilization for flap supercharge saw a significant increase (15.9% vs. 7%, p < 0.001), while the use of the superior inferior epigastric vein (SIEV) decreased (5.1% vs. 17.1%, p = 0.01). Preceding MIS, SIEV was the primary choice for flap supercharge (96.0%, p < 0.001), whereas post-introduction, the contralateral DIEP pedicle gained prominence (75.9%, p < 0.001). There was also an increased utilization of thoracodorsal artery and lateral thoracic artery following MIS. CONCLUSION: These findings underscore the profound impact of MIS on the strategic choices made in DIEP flap-based breast reconstruction. TRIAL REGISTRATION: This study is retrospectively registered on ClinicalTrials.gov (NCT06321549).

MRA for Preoperative Planning and Postoperative Management of Perforator Flap Surgeries: A Review.

Perforator flap magnetic resonance angiography (MRA) has emerged as a widely accepted and preferred modality for perforator flap mapping at several institutions. Autologous perforator flaps are a type of reconstructive microsurgical technique that involves transferring skin and fat from one part of the patient's body to another to replace tissue lost due to trauma, cancer resection, or other reasons. Autologous perforator flaps are based on a specific perforating blood vessel perfusing the transferred tissue. Hence, the surgery relies on the precise identification and mapping of perforating vessels to ensure successful outcomes. With its superior soft tissue contrast and multiplanar imaging capabilities, MRA has shown great potential in providing accurate and detailed visualization of perforator anatomy, size, and course. This review article summarizes the current literature on perforator flap MRA, including its technical considerations, imaging protocols, postprocessing, and reporting, specifically for autologous breast reconstructions. The advantages and limitations of MRA in evaluating perforator flaps are discussed, including its role in preoperative planning, intraoperative guidance, and postoperative assessment. Anatomy, brief surgical technique, specific technical modifications, and reporting of most commonly performed autologous breast flaps are described. Recent advancements in Perforator flap surgery and MRA techniques are discussed. Additionally, we examine the emerging role of artificial intelligence and machine learning in improving the accuracy and efficiency of perforator flap MRA interpretation. LEVEL OF EVIDENCE: 5 TECHNICAL EFFICACY: Stage 5.

Experimental study of slow-released Angiogenin by silicon micro-needle in improving blood support to multiple-territory perforator flaps in rats.

This research aimed to investigate the effect of slow-released angiogenin by silicon micro-needle on angiogenesis in the Choke zone of dorsal multiple-territory perforator flap in rats, as well as its mechanism. Thirty-six adult Sprague-Dawley (SD) rats were randomly divided into control group, model group, and four experimental groups. In model group, slow-release saline through a silicon micro-needle was placed in choke II zone of the flap 7 days before the operation. For rats in four experimental groups, angiogenin was released via micro-needle in the choke I and choke II zones of the cross-zone flap 7 days before and 3 days before flap surgery, respectively. A 12 cm × 3 cm cross-zone perforator flap model was made on the back of all five groups. The flap survival rate in slow-release angiopoietin group was statistically higher than that in model group (P<0.05). Angiogenin in choke zone of the flap was increased in slow-release angiogenin group (P<0.05). In slow-release angiogenin group, the micro-vessel density was increased and the arteriovenous diameter was decreased, while the arteriovenous diameter was increased in model group (P<0.05). The levels of vascular endothelial growth factor A (VEGF-A) and angiotensin 1 (ANG-1) in choke zone were both elevated in slow-release angiogenin group (P<0.05). The expression of CD31 was significantly elevated in flaps of experimental groups (P<0.05). Micro-needle to slow release Angiogenin can increase the drug concentration in the tissues of the choke zone, promote the vascularization of rat dorsal crossover area perforator flap, reduce the possibility of flap ischemic necrosis, and improve the flap survival rate.

Application of antibiotic bone cement combined with lobulated perforator flap based on descending branch of the lateral circumflex femoral artery in treatment of infected traumatic tissue defects of foot.

OBJECTIVE: To evaluate the clinical effectiveness of antibiotic bone cement combined with the lobulated perforator flap based on the descending branch of the lateral circumflex femoral artery (d-LCFA) in the treatment of infected traumatic tissue defects in the foot, in accordance with the Enhanced Recovery after Surgery (ERAS) concept. METHODS: From December 2019 to November 2022, 10 patients with infected traumatic tissue defects of the foot were treated with antibiotic bone cement combined with the d-LCFA lobulated perforator flap. The cohort comprised 6 males and 4 females, aged 21 to 67 years. Initial infection control was achieved through debridement and coverage with antibiotic bone cement, requiring one debridement in nine cases and two debridements in one case. Following infection control, the tissue defects were reconstructed utilizing the d-LCFA lobulated perforator flap, with the donor site closed primarily. The flap area ranged from 12 cm×6 cm to 31 cm×7 cm. Postoperative follow-up included evaluation of flap survival, donor site healing, and ambulatory function of the foot. RESULTS: The follow-up period ranged from 7 to 24 months, averaging 14 months. Infection control was achieved successfully in all cases. The flaps exhibited excellent survival rates and the donor site healed by first intention. Based on the American Orthopaedic Foot and Ankle Society (AOFAS) ankle-hindfoot scale, pain and function were evaluated as excellent in 3 cases, good in 5 cases, and moderate in 2 cases. CONCLUSION: The application of antibiotic bone cement combined with the d-LCFA lobulated perforator flap is an effective treatment for infected traumatic tissue defects of the foot with the advantages of simplicity, high repeatability, and precise curative effects. The application of the d-LCFA lobulated perforator flap in wound repair causes minimal damage to the donor site, shortens hospital stays, lowers medical expenses, and accelerates patient rehabilitation, aligning with the ERAS concept. Therefore, it is a practice worth promoting in clinical use.

The Application of Preoperative Computed Tomography Angiography and Color Ultrasound Assisted Lower Limb Perforator Flap Design in the Repair of Lower Limb Soft Tissue Defects.

Objective: The goal of this study was to explore the application effect of preoperative computed tomography (CT) angiography and color ultrasound-assisted design of lower limb perforator flaps in the repair of lower limb soft tissue defects. Repair of soft tissue defects in the lower limbs is a challenging surgical task, and accurate preoperative location of vascular structures and detailed design of the surgical plan are crucial to the success of the surgery. This study aims to improve the accuracy and effectiveness of lower limb perforator flap repair surgery by introducing CT angiography and color ultrasound technology. Methods: Sixty-four patients who underwent lower limb soft tissue defect repair with perforator flaps were enrolled at our hospital from February 2020 to February 2023. According to their admission time, they were divided into two groups: 32 patients admitted before June 31, 2022, were included in the control group, and preoperative color Doppler ultrasound was used to assist in designing the lower limb perforator flap; 32 patients admitted after June 31, 2022, were included in the study group, and preoperative CT angiography and color Doppler ultrasound were used to assist in designing the lower limb perforator flap. Specifically, we conducted detailed records and analyzes of patients' age distribution, gender ratio, and relevant medical history. This demographic information will help reveal whether there are differences in the effectiveness of preoperative CT angiography and color ultrasound-assisted lower extremity perforator flap design among different patient groups. By considering these key factors, we can more accurately assess the actual utility of new technologies in different patient groups and provide more specific guidance for clinical practice.The therapeutic effects of the two groups of patients were recorded. The differences between the preoperative CT angiography measurements and intraoperative actual measurements of the study group were compared. Clinical indicators, sensory function in the graft area, flap survival rate, flap complication rate, and donor area complication rate were compared between the two groups. The satisfaction of patients in the two groups with the recovery of the surgical area was also compared. Results: The treatment success rate of the study group was higher than that of the control group (P < .05). There was no significant difference in the preoperative CT angiography measurements (shallow branch localization, shallow branch starting diameter, shallow branch length, deep branch starting diameter) and intraoperative actual measurements of the study group (P > .05). The operation time and intraoperative blood loss of the study group were shorter than those of the control group (P < .05), and there was no significant difference in flap harvesting area and length of hospital stay between the two groups (P > .05). There was a difference in sensory function in the graft area between the two groups, with a higher proportion of S4 grade in the study group and better recovery compared to the control group (P < .05). There was no significant difference in satisfaction evaluation between the two groups (P > .05). Conclusion: Preoperative CT angiography and color ultrasound-assisted design of lower limb perforator flaps have shown significant clinical advantages in repairing lower limb soft tissue defects, improving treatment effects and surgical efficiency. In clinical practice, this technology is expected to reduce surgical complexity, shorten surgical time, reduce the risk of intraoperative bleeding, and achieve effective defect repair while maintaining or improving the patient's sensory function.However, there are some limitations to the study, such as the relatively small sample size and single-center nature. Future research can optimize the operation process of this technology, expand the scope of research, and explore its application in the repair of soft tissue defects caused by specific causes. This technology may provide more precise and effective options for personalized treatment, especially for patients who need to preserve more sensory function.

Dihydrocapsaicin suppresses the STING-mediated accumulation of ROS and NLRP3 inflammasome and alleviates apoptosis after ischemia-reperfusion injury of perforator skin flap.

Avascular necrosis frequently occurs as a complication following surgery involving the distal perforator flap. Dihydrocapsaicin (DHC) can protect tissue from ischemia-reperfusion (I/R) injury, but its specific role in multizone perforator flaps remains unclear. In this study, the prospective target of DHC in the context of I/R injury was predicted using network pharmacology analysis. Flap viability was determined through survival area analysis, laser Doppler blood flow, angiograms, and histological examination. The expressions of angiogenesis, apoptosis, NLR family pyrin domain containing 3 (NLRP3) inflammasome, oxidative stress, and molecules related to cyclic guanosine monophosphate (GMP)-adenosine monophosphate synthase (cGAS)-interferon gene stimulant (STING) pathway were assessed using western blotting, immunofluorescence, TUNEL staining, and dihydroethidium (DHE) staining. Our finding revealed that DHC promoted the perforator flap survival, which involves the cGAS-STING pathway, oxidative stress, NLRP3 inflammasome, apoptosis, and angiogenesis. DHC induced oxidative stress resistance and suppressed the NLRP3 inflammasome, preventing apoptosis in vascular endothelial cells. Through regulation of STING pathway, DHC controlled oxidative stress in endothelial cells and NLRP3 levels in ischemic flaps. However, activation of the cGAS-STING pathway led to the accumulation of reactive oxygen species (ROS) and NLRP3 inflammasome, thereby diminishing the protective role of DHC. DHC enhanced the survival of multidomain perforator flaps by suppressing the cGAS-STING pathway, oxidative stress, and the formation of NLRP3 inflammasome. These findings unveil a potentially novel mechanism with clinical significance for promoting the survival of multidomain perforator flaps.

Systematic review of the free thoracodorsal artery perforator flap for head and neck reconstruction.

BACKGROUND: The thoracodorsal artery perforator (TDAP) flap has gained interest as a option for reconstruction of head and neck defects while minimizing donor site morbidity as compared to traditional workhorse flaps. The primary aim of this systematic review is to assess the postoperative outcomes and efficacy of this flap. METHODS: Several databases were screened for relevant citations. The quality of studies and risk of bias were evaluated using the MINORS scoring system. RESULTS: Twenty articles containing 168 patients undergoing at least one TDAP flap reconstruction met the inclusion criteria. There were no incidences of total flap failure and only 10 incidences of partial flap failure (5.95 %). Flap complications and donor site morbidity was low. The average MINORS score of the studies suggested a moderately high amount of bias. CONCLUSIONS: Based on limited quality evidence, this review suggests that TDAP flap is a safe and feasible option for head and neck reconstruction with comparable success rates as other commonly used flaps, with low complication rate and donor site morbidity. Further large-scale studies are warranted.

Indications and versatility of the posterior tibial artery flap in head and neck reconstruction.

Importance Free tissue transfer for reconstruction of the head and neck requires complicated repair of complex anatomy. The posterior tibial flap is a free tissue flap that has viability and versatility to be used for complex reconstructions that is not offered by other free flaps. OBJECTIVE: The posterior tibial artery flap is a perforator flap which is found between the flexor digitorum longus and the soleus. It has been described as both a pedicled flap for lower extremity reconstruction as well as a free flap, including for head and neck reconstruction. Limited data exists on the subject in the English literature. The objective of this study is to present our experience with the flap in the head and neck. DESIGN: Retrospective review of cases from a single institution between October 2019 and May 2023. Primary indications included patients whose defects were felt to be larger than a conventional radial forearm free flap that were not well served by the anterolateral thigh flap, either because of body habitus or room for the associated muscle. SETTING: Tertiary academic hospital system performing free tissue transfer reconstruction of within the head and neck. RESULTS: Fifteen patients underwent posterior tibial artery free flap during the study period. Indications for flap reconstruction included oral cavity, tongue, oropharynx and skin of the scalp and forehead. Flap size ranged from 24cm2 to 143cm2. Only one flap failure was observed. Flap harvest time was universally under forty-six minutes, and as little as thirty-two. CONCLUSION: The posterior tibial artery flap is a useful option in head and neck reconstruction. It provides an intermediary in size and bulk between the radial forearm and the anterolateral thigh flap. Additionally, it provides a straightforward harvest with minimal donor site morbidity.