Vascular Complications After Radiotherapy in Head and Neck Free Flap Reconstruction: Clinical Outcome Related to Vascular Biology

A comparative analysis of free fibula flap donor leg and recipient vessel selection in composite oromandibular defect reconstructions

BACKGROUND

The free fibula flap (FFF) is acknowledged as the primary choice for reconstructing composite oromandibular defects (COMDs), yet the impact of donor leg selection remains inadequately explored. This study aims to investigate the correlation between flap failure and the choice of donor leg and recipient vessel side.

MATERIALS AND METHODS

In a retrospective analysis spanning 2011 to 2020, FFFs for COMD were examined using electronic records. Patient data, comorbidities, radiation history, FFF details, and intraoperative variables were considered. Laterality was categorized into "Cis" and "Trans" groups, further subclassified based on blood supply. Analyses involved logistic regression, bivariate analysis, and propensity score matching.

RESULTS

A total of 155 subjects with intraoral mucosal defects repaired only by the skin paddle of FFF were included. Cases were categorized into "Cis" (n = 65; 42%) and "Trans" (n = 90; 58%) groups based on COMD side and donor leg selection. No significant baseline differences emerged. Logistic regression found no laterality impact on total FFF failure. Initially, gender correlated with flap failure, but adjustment diminished the association. Partial skin paddle necrosis correlated with diabetes, not laterality. Propensity score matching revealed no significant differences between right and left legs in laterality or total flap failure risk. Subgroup analysis found no differences in parameters or flap failure rates within "Cis" and "Trans" groups.

CONCLUSION

Donor leg selection in COMD reconstruction with FFFs does not exhibit specificity. Furthermore, despite potential limitations in vessel anastomosis due to pedicle length or trauma history, recipient vessel side selection does not evidently affect flap failure.

Evaluation of Ischemic Time and Complications in Free Jejunum Transfer

BACKGROUND

In free jejunum transfer, knowing the ischemic tolerance time of the jejunum is crucial. It helps determine the need for reharvesting if an unexpected situation prolongs the ischemic time. The current ischemic tolerance time in humans is unknown. We investigated the relationship between ischemic time and postoperative complications in head and neck cancer patients who underwent free jejunum transfer.

METHODS

The study included 76 patients with available medical records out of 103 patients who underwent free jejunum transfer between 2009 and 2023. The association between the surgical procedure, including ischemic time, and patient's background, and flap engraftment, stenosis of the intestinal anastomosis, the swallowing function, and other complications was investigated.

RESULTS

The ischemic time for jejunal flaps ranged from 1 h 24 min to 6 h, with a mean of 197 ± 55.5 min. In 72 patients, the jejunum was successfully engrafted, but vascular occlusion occurred in another four patients. In three of these patients, jejunal necrosis occurred, and there was no specific trend in ischemic time. Stenosis of the intestinal anastomosis occurred in 17 cases (22%), with ischemic time (≥3 h) and age (≥75 years) being significant factors for stenosis (ischemic time: 30% vs. 10%, p = 0.048, age: 50% vs. 15%, p < 0.01). No significant correlations were observed with other complications or the swallowing function.

CONCLUSION

There was no specific trend between ischemic time and jejunal survival rate, indicating that an ischemic time within 6 h may not have affected engraftment. Although we have recently performed intestinal anastomosis prior to vascular anastomosis, the choice of surgical technique should be adapted to the patient's age and background.

Effect of Preoperative Neck Radiotherapy on the Reconstruction of Head and Neck Defects With the Supraclavicular Artery Island Flap

Purpose: The supraclavicular artery island (SAI) flap is commonly used in the reconstruction of head and neck defects. However, the safety of SAI flaps for neck irradiated patient needs to be verified. To investigate the safety of using the SAI flap for patients who have undergone neck radiotherapy, as well as the risk factors for flap complications. Materials and Methods: Sixty-one patients (16 irradiated and 45 nonirradiated) with SAI flap-reconstructed head and neck defects were included, and relevant data were collected retrospectively. The gender, age, body mass index, presence of diabetes mellitus, preoperative albumin level, and flap size between irradiated and nonirradiated patients had no significant difference. Results: No significant difference was observed in the incidence of complications (total, mild, or severe) between the radiotherapy and nonradiotherapy groups. In univariate analysis, preoperative radiotherapy was not associated with postoperative complications of the SAI flap procedure (P = 1.00), while a low preoperative albumin level was a significant risk factor for postoperative complications (P < .05). Conclusions: Our data suggest that preoperative radiotherapy does not increase the risk of SAI flap postoperative complications compared with surgical reconstruction alone.

The Use of Fibrinolytic Agents in the Salvage of Free Flaps: A Systematic Review

BACKGROUND

Microvascular thrombosis following free tissue transfer presents a complex challenge for surgeons and carries the potential risk of flap failure. The application of fibrinolytic agents represents a robust therapeutic option. The aim of this systematic review is to provide a comprehensive overview of the clinical use of fibrinolytic drugs in the rescue of compromised free flaps.

METHODS

A systematic literature search for clinical studies detailing the utilization of fibrinolytic agents for salvaging free flaps was conducted using the PubMed and Web of Science databases. The inclusion criteria encompassed English-language publications that specifically addressed the clinical application of fibrinolytic agents for free-flap salvage.

RESULTS

A total of 331 articles were screened after excluding duplicates, with 56 meeting the inclusion criteria. Among these, 21 were clinical trials (evidence level III), and 35 were case studies (evidence level IV/V). In total, 459 flaps underwent treatment with fibrinolytic agents.

CONCLUSION

The application of fibrinolytic agents appears to be a valuable intervention for rescuing compromised free flaps attributable to microvascular compromise. Notably, no prospective randomized trials have been published on this subject, and the evidence within the existing literature is characterized by its limited and heterogeneous nature. Further research is imperative to gather data on the efficacy, dosage, and safety profile of fibrinolytic agents.

The Ischemic Tolerance up to Four Hours of Free Jejunum Flap: A Retrospective Cohort Study

BACKGROUND

 While free jejunum transfer (FJT) following total pharyngo-laryngo-esophagectomy (TPLE) is a reliable reconstruction technique, the jejunum flap is viewed as more susceptible to ischemia than a standard free flap. Animal studies have indicated that the jejunum can tolerate ischemia for as little as 2 to 3 hours. Clinical studies also reported increased complications after the FJT with more than 3 hours of ischemia. Traditionally, our institution has carried out FJT with an initial intestinal anastomosis, followed by a vascular anastomosis, which often results in extended jejunal ischemia time. In this study, we retrospectively examined the actual tolerance of the jejunum to ischemia, considering perioperative complications and postoperative dysphagia.

METHODS

 We retrospectively studied 402 consecutive cases involving TPLE + FJT. Patients were divided into five groups based on jejunum ischemia time (∼119 minutes, 120∼149 minutes, 150∼179 minutes, 180∼209 minutes, 210 minutes∼), with each variable and result item compared between the groups. Univariate and multivariate analyses were conducted to identify independent factors influencing the four results: three perioperative complications (pedicle thrombosis, anastomotic leak, surgical site infection) and dysphagia at 6 months postoperatively.

RESULTS

 The mean jejunal ischemia time was 164.6 ± 28.4 (90-259) minutes. When comparing groups divided by jejunal ischemia time, we found no significant differences in overall outcomes or complications. Our multivariate analyses indicated that jejunal ischemia time did not impact the three perioperative complications and postoperative dysphagia.

CONCLUSION

 In TPLE + FJT, a jejunal ischemia time of up to 4 hours had no effect on perioperative complications or postoperative dysphagia. The TPLE + FJT technique, involving a jejunal anastomosis first followed by vascular anastomosis, benefits from an easier jejunal anastomosis but suffers from a longer jejunal ischemia time. However, we found that ischemia time does not pose significant problems, although we have not evaluated the effects of jejunal ischemia extending beyond 4 hours.

Early outcomes of osteofascial versus osteocutaneous fibula free flap mandibular reconstruction

BACKGROUND

This study compares early outcomes of osteofascial fibula free flap (OF-FFF) with donor-site primary closure and osteocutaneous (OC) FFF with donor-site skin grafting in segmental mandibular reconstruction.

METHODS

A retrospective chart review of FFF mandibular reconstruction patients (2006-2022) divided into OF-FFF and OC-FFF groups. Clinical data, operative parameters, and early postoperative outcomes (≤ 90 days) were analyzed.

RESULTS

The study included 67 patients (39 OF-FFF, 28 OC-FFF). OF-FFF had significantly lower donor-site complications (12.8% vs. 53.6%, p < 0.001) and revision surgeries (7.7% vs. 35.7%, p = 0.004) compared to OC-FFF. Recipient-site (28.2% vs. 25%, p = 0.77) and flap (15.4% vs. 17.9%, p > 0.99) complications were comparable.

CONCLUSIONS

OF-FFF mandibular reconstruction with donor-site primary closure is a safe and reliable technique associated with superior donor-site and comparable flap and recipient-site outcomes to OC-FFF, thus may be considered as a viable alternative to OC-FFF for selected patients.

The Perfect Timing-Immediate versus Delayed Microvascular Reconstruction of the Mandible

In this retrospective study, the clinical and economic implications of microvascular reconstruction of the mandible were assessed, comparing immediate versus delayed surgical approaches. Utilizing data from two German university departments for oral and maxillofacial surgery, the study included patients who underwent mandibular reconstruction following continuity resection. The data assessed included demographic information, reconstruction details, medical history, dental rehabilitation status, and flap survival rates. In total, 177 cases (131 male and 46 females; mean age: 59 years) of bony free flap reconstruction (72 immediate and 105 delayed) were included. Most patients received adjuvant treatment (81% with radiotherapy and 51% combined radiochemotherapy), primarily for tumor resection. Flap survival was not significantly influenced by the timing of reconstruction, radiotherapy status, or the mean interval (14.5 months) between resection and reconstruction. However, immediate reconstruction had consumed significantly fewer resources. The rate of implant-supported masticatory rehabilitation was only 18% overall. This study suggests that immediate jaw reconstruction is economically advantageous without impacting flap survival rates. It emphasizes patient welfare as paramount over financial aspects in clinical decisions. Furthermore, this study highlights the need for improved pathways for masticatory rehabilitation, as evidenced by only 18% of patients with implant-supported dentures, to enhance quality of life and social integration.

Safety and reliability of the internal jugular vein for venous anastomoses in head and neck oncological reconstruction: A retrospective study

This study aimed to assess the efficacy of utilizing the internal jugular vein (IJV) as the primary recipient site for venous anastomoses in head and neck oncological reconstruction. Patients who underwent a free flap reconstruction of the head and neck were retrospectively included. Venous anastomoses were preferentially performed less than 1 cm from the IJV, either end-to-side (EtS) on the IJV, or end-to-end (EtE) on the origin of the thyrolingofacial venous (TLF) trunk. When the pedicle length was insufficient to reach the IJV, anastomoses were performed EtE to a size-matched cervical vein. Of the 246 venous anastomoses, 216 (87.8%) were performed less than 1 cm from the IJV, including 150 EtS on the IJV (61.0%), and 66 EtE on the TLF trunk (26.8%). Thirty veins (12.1%) were anastomosed EtE on other cervical veins more than 1 cm from the IJV. Two venous thromboses occurred (0.9%) and were successfully managed after revision surgery. There was no evidence of an increased thrombosis rate in high-risk or pre-irradiated patients. These findings suggest that the internal jugular vein is safe and reliable as a first-choice recipient vessel for free flap transfers in head and neck oncological reconstruction.

The impact of post-mastectomy radiation timing on overall outcomes of autologous free-flap breast reconstruction

BACKGROUND

The optimal timing of post-mastectomy radiation therapy (PMRT) in autologous breast reconstruction is controversial. Our study compares overall reconstructive outcomes in patients who received post-mastectomy radiation therapy either before or after the autologous flap.

METHODS

A single-center retrospective review was performed for patients who underwent free flap breast reconstruction and post-mastectomy radiation from January 2004 through January 2021. Demographic, intraoperative, and post-operative variables were recorded.

RESULTS

A total of 452 free flaps were identified, and 82 underwent PMRT. 59.8% were radiated with an expander prior to free flap surgery (PreFlap), and 40.2% flaps underwent PMRT (PostFlap). PostFlap patients were significantly younger (43.0 vs. 47.9 years, p = .016). There were no significant differences in free flap outcomes between the two cohorts including thrombosis, venous congestion, flap loss, takebacks, fat necrosis, seroma, or infection. Mastectomy skin flap necrosis was significantly higher in the PostFlap cohort (9.1% vs. 0%, p = .032), but nipple necrosis rates did not differ. There were no significant differences in number or need for revision surgeries, fat necrosis, or fat grafting between groups. However, there were significantly more total reconstructive complications, including infection and wound breakdown, experienced by the PreFlap cohort (46.9% vs. 24.2%, p = .038).

CONCLUSIONS

Timing of PMRT did not impact free flap outcomes, but those who had the expander radiated experienced significantly more complications overall. For the 34.7% of patients in the preFlap group who planned for autologous reconstruction form initial consultation, radiation after the flap may have improved their overall outcomes. As added complications cause delays in cancer therapy and final reconstruction, our results suggest that PMRT of the flap when possible may improve the overall experience for breast cancer patients.

Risk Factors for Flap Loss: Analysis of Donor and Recipient Vessel Morphology in Patients Undergoing Microvascular Head and Neck Reconstructions

In microvascular head and neck reconstruction, various factors such as diabetes, alcohol consumption, and preoperative radiation hold a risk for flap loss. The primary objective of this study was to examine the vessel morphology of both recipient and donor vessels and to identify predictors for changes in the diameters of H.E.-stained specimens associated with flap loss in a prospective setting. Artery and vein samples (N = 191) were collected from patients (N = 100), with sampling from the recipient vessels in the neck area and the donor vessels prior to anastomosis. External vessel diameter transverse (ED), inner vessel diameter transverse (ID), thickness vessel intima (TI), thickness vessel media (TM), thickness vessel wall (TVW), and intima-media ratio (IMR) for the recipient (R) and transplant site (T) in arteries (A) and veins (V) were evaluated using H.E. staining. Flap loss (3%) was associated with increased ARED (p = 0.004) and ARID (p = 0.004). Preoperative radiotherapy led to a significant reduction in the outer diameter of the recipient vein in the neck (p = 0.018). Alcohol consumption (p = 0.05), previous thrombosis (p = 0.007), and diabetes (p = 0.002) were associated with an increase in the total thickness of venous recipient veins in the neck. Diabetes was also found to be associated with dilation of the venous media in the neck vessels (p = 0.007). The presence of cardiovascular disease (CVD) was associated with reduced intimal thickness (p = 0.016) and increased total venous vessel wall thickness (p = 0.017) at the transplant site. Revision surgeries were linked to increased internal and external diameters of the graft artery (p = 0.04 and p = 0.003, respectively), while patients with flap loss showed significantly increased artery diameters (p = 0.004). At the transplant site, alcohol influenced the enlargement of arm artery diameters (p = 0.03) and the intima-media ratio in the radial forearm flap (p = 0.013). In the anterolateral thigh, CVD significantly increased the intimal thickness and the intima-media ratio of the graft artery (p = 0.01 and p = 0.02, respectively). Patients with myocardial infarction displayed increased thickness in the A. thyroidea and artery media (p = 0.003). Facial arteries exhibited larger total vessel diameters in patients with CVD (p = 0.03), while facial arteries in patients with previous thrombosis had larger diameters and thicker media (p = 0.01). The presence of diabetes was associated with a reduced intima-media ratio (p < 0.001). Although the presence of diabetes, irradiation, and cardiovascular disease causes changes in vessel thickness in connecting vessels, these alterations did not adversely affect the overall success of the flap.

A Systematic Review of Microsurgical Pedicle Lengthening in Free Tissue Transfer

INTRODUCTION

Traumatic injuries that require free tissue flaps for reconstruction may require vascular pedicle extension between the flap and recipient vessels to form a clear anastomosis. Currently, a variety of techniques are used, each with their own potential benefits and harms. In addition, reports in the literature conflict on the reliability of pedicle extensions of vessels in free flap (FF) surgery. The objective of this study is to systematically assess the available literature about outcomes of pedicle extensions in FF reconstruction.

METHODS

A comprehensive search was performed for relevant studies published up to January 2020. Study quality was assessed using the Cochrane Collaboration risk of bias assessment tool and a set of predetermined parameters was extracted by 2 investigators independently for further analysis. The literature review yielded 49 studies investigating pedicled extension of FF. Studies meeting inclusion criteria underwent data extraction focusing on demographics, conduit type, microsurgical technique, and postoperative outcomes.

RESULTS

The search yielded 22 retrospective studies totaling 855 procedures from 2007 to 2018 in which 159 complications (17.1%) were reported in patients aged between 39 and 78 years. Overall heterogeneity of articles included in this study was high. Free flap failure and thrombosis were the 2 most prevalent major complications noted: vein graft extension technique had the highest rate of flap failure (11%) in comparison with the arterial graft (9%) and arteriovenous loops (8%). Arteriovenous loops had a rate of thrombosis of 5% versus 6% in arterial grafts and 8% in venous grafts. Bone flaps maintained the highest overall complication rates per tissue type at 21%. The overall success rate of pedicle extensions in FFs was 91%. Arteriovenous loop extension resulted in a 63% decrease in the odds of vascular thrombosis and a 27% decrease in the odds of FF failure when compared with venous graft extensions (P < 0.05). Arterial graft extension resulted in a 25% decrease in the odds of venous thrombosis and a 19% decrease in the odds of FF failure when compared with venous graft extensions (P < 0.05).

CONCLUSIONS

This systematic review strongly suggests that pedicle extensions of the FF in a high-risk complex setting are a practical and effective option. There may be a benefit to using arterial versus venous conduits, although further examination is warranted given the small number of reconstructions reported in the literature.

Free Flaps for Skin and Soft Tissue Reconstruction in the Elderly Patient: Indication or Contraindication

BACKGROUND

Increased lifespan and the improvement of medical treatment have given rise to research in reconstructive procedures in elderly patients. Higher postoperative complication rates, longer rehabilitation, and surgical difficulties remain a problem in the elderly. We asked whether a free flap in elderly patients is an indication or a contraindication and performed a retrospective, monocentric study.

METHODS

Patients were divided into two groups (YOUNG 0-59 years; OLD > 60 years). The endpoint was the survival of flaps and their dependence on patient- and surgery-specific parameters using multivariate analysis.

RESULTS

A total of 110 patients (OLD n = 59) underwent 129 flaps. The chance of flap loss increased as soon as two flaps were performed in one surgery. Anterior lateral thigh flaps had the highest chance for flap survival. Compared with the lower extremity, the head/neck/trunk group had a significantly increased chance of flap loss. There was a significant increase in the odds of flap loss in linear relation to the administration of erythrocyte concentrates.

CONCLUSION

The results confirm that free flap surgery can be indicated as a safe method for the elderly. Perioperative parameters such as two flaps in one surgery and transfusion regimens must be considered as risk factors for flap loss.

Preoperative anemia: Predictor of free flap reconstruction complications in head and neck cancer

Free flap reconstruction has been the mainstay among reconstruction surgeries for head and neck cancer. Intraoperative and postoperative hemoglobin (Hb) levels were both possible risk factors of flap failure and had been discussed widely. However, few investigations of preoperative Hb were seen in the previous study with its effect to flap condition remain uncertain and no conclusions in the literature. Patients who underwent free flap reconstruction after head and neck surgery in our institution between May 2014 and May 2019 were enrolled. The postoperative flap condition was observed carefully, and re-exploration was performed if necessary. We then retrospectively collected patient data with several intraoperative and postoperative indices. A total of 598 patients were enrolled in our study. The total major flap complication rate was 10.6%, with an overall success rate of 89.4%. They were predominantly male (95%), and most of them underwent free flap reconstruction for the first time (91%). A total of 81 (13%) patients received radiotherapy before reconstruction. Among all factors, the preoperative Hb level and free flap type showed significance in univariate and multivariate analyses. A previous history of radiotherapy, body mass index, nutrition status, or poorly controlled diabetes mellitus showed no significant results in either univariate or multivariate analysis. Our study showed that a lower preoperative Hb level affects free flap survival. Meanwhile, preoperative radiotherapy history has no significant influence in either univariate or multivariate analysis.

Surgical and demographic predictors of free flap salvage after takeback: A systematic review

BACKGROUND

Microsurgical free tissue transfer (FTT) is a widely employed surgical modality utilized for reconstruction of a broad range of defects, including head and neck, extremity, and breast. Flap survival is reported to be 90%-95%. When FTT fails, salvage procedures aim at establishing reperfusion while limiting ischemia time-with salvage rates between 22% and 67%. There are limited data-driven predictors of successful salvage present in the literature. This systematic review aims to identify predictors of flap salvage.

METHODS

A systematic literature review was conducted per PRISMA guidelines. Articles included in the final analysis were limited to those investigating FTT salvage procedures and included factors impacting outcomes. Cohort and case series (>5 flaps) studies up until March 2021 were included. Chi-square tests and linear regression modeling was completed for analysis.

RESULTS

The patient-specific factors significantly associated with salvage included the absence of hypercoagulability (p < .00001) and no previous salvage attempts (p < .00001). Case-specific factors significantly associated with salvage included trunk/breast flaps (p < .00001), fasciocutaneous/osteocutaneous flaps (p = .006), venous compromise (p < .00001), and shorter time from index procedure to salvage attempt (R = .746). Radiation in the head and neck population was significantly associated with flap salvage failure.

CONCLUSIONS

Given the complexity and challenges surrounding free flap salvage procedures, the goal of this manuscript was to present data helping guide surgical decision-making. Based on our findings, patients without documented hypercoagulability, no previous salvage attempts, fasciocutaneous/osteocutaneous flaps, trunk/breast flaps, and a shorter time interval post-index operation are the best candidates for a salvage attempt.

How do i salvage that flap?; An evidence-based primer on salvage techniques for head & neck microvascular free flaps

Interventional strategies for dealing with microvascular free flap failure are varied among institutions and even individual surgeons. This systematic review aims to identify the published methods for salvaging a failing free flap and provide surgeons with a comprehensive toolset for successful intervention. A title and abstract search of the PubMed, Embase, and Web of Science databases was performed. 1694 abstracts were screened by three reviewers according to Prisma guidelines. 62 full text articles meeting inclusion criteria detailed techniques which were separated into the categories of thrombectomy, thrombolysis, leech therapy, vascular fistula, and an "other" category outlining techniques which did not fit into the prior framework. Assessment of the efficacy of individual salvage techniques is limited due to limited empirical data, however, the approach to successful salvage should be based on timely identification of flap compromise, followed by the implementation of one or several of the aforementioned techniques.

Risk factors associated with postoperative complications following free flap reconstruction of head and neck defects

BACKGROUND

Free flap reconstruction of head and neck defects is routinely performed with a high success rate nowadays. However, postoperative complications are still commonly observed. The aim of this study is to investigate risk factors correlated with postoperative complications following free flap reconstruction of head and neck defects.

METHODS

A retrospective study of all patients undergoing free flap reconstruction of head and neck defects between January 2018 and January 2020 at Sun Yat-sen Memorial Hospita, Guangzhou, China was performed. Preoperative, intraoperative, and postoperative data were collected retrospectively. The primary outcome variables were postoperative complications, which were divided into medical and surgical complications. All patients were grouped by either complications or no complications. Univariate and multivariate logistic regression models were used to identify risk factors predicting complications.

RESULTS

850 patients underwent free flap reconstruction of head and neck defects during the study period (Male: 65.29%; Mean [SD] age: 54.90 [13.78] years). Postoperative complications developed in 125 (14.71%) patients, among which, 101 (11.88%) patients developed surgical complications, 29 (3.41%) patients developed medical complications and 5 (0.59%) patients developed both surgical and medical complications. Total flap necrosis was observed in 11 (1.29%) patients. After multivariate analysis, several risk factors incluing postoperative ICU admission, coronary heart disease, post radiotherapy surgery and flap types were identified correlated with postoperative complications.

CONCLUSIONS

Our study identified related variables for a higher risk of postoperative complications development following free flap reconstruction of head and neck defects. Early detection of these risk factors will improve prognosis.

Perfusion of microvascular free flaps in head and neck reconstruction after prior neck dissection and irradiation

Microvascular free flaps are frequently used for head and neck reconstruction after prior neck dissection (ND) and neck irradiation (RTX). The aim of this study was to investigate the influence of ND and RTX on flap perfusion as a critical factor for flap success. Overall, 392 patients reconstructed with a microvascular fasciocutaneous flap (FF) or perforator flap (PF) in the head and neck region between 2011 and 2020 were analysed retrospectively. Flap perfusion measured intraoperatively and postoperatively with the O2C tissue oxygen analysis system was compared between patients who had received neither ND nor RTX (controls), patients who had received ND but no RTX (ND group), and patients who had received both ND and RTX (ND+RTX group). Intraoperative and postoperative flap blood flow was decreased in FFs in ND group patients compared to controls (median 66.3 AU vs 86.0 AU, P = 0.023; median 73.5 AU vs 93.8 AU, P = 0.045, respectively). In the multivariable analysis, these differences showed a tendency to persist (P = 0.052 and P = 0.056). Flap success rates were similar in control patients, ND patients, and ND+RTX patients (98.7%, 94.0%, and 97.6%, respectively). Flap perfusion is not reduced in FFs and PFs in patients who have undergone ND or ND and RTX. This indicates that neck dissection and neck irradiation should not be contraindications for microvascular free flap reconstruction.

Critical Importance of the First Postoperative Days After Head and Neck Free Flap Reconstruction: An Analysis of Timing of Reoperation Using the National Surgical Quality Improvement Program Database

BACKGROUND

Head and neck free flaps remain associated with considerable rates of take-back and prolonged hospital length of stay. However, there have been no studies on a national level benchmarking the timeline and predictors of head and neck free flap take-back.

METHODS

Patients undergoing head and neck free flap reconstruction from the American College of Surgeons National Surgical Quality Improvement Program 2012-2019 database were analyzed to determine the rates of take-back. Timing and rates of unplanned head and neck free flap take-backs were stratified by tissue type and postoperative day (POD) over the first month. Weibull survival models were used to compare rates of take-backs among time intervals. Multivariable logistic regression was used to identify the independent predictors of take-back.

RESULTS

Three thousand nine hundred six head and neck free flaps were analyzed. The mean daily proportion of patients experiencing take-back during PODs 0 to 1 was 0.95%; this dropped significantly to a mean daily proportion of 0.54% during POD 2 (P < 0.01). In addition, there were significant drops in take-back when comparing POD 2 (0.54%) to POD 3 (0.26%) and also when comparing POD 4 (0.20%) with PODs 5 to 30 (0.032% per day) (P < 0.05). The soft tissue and osseous flap populations demonstrated a similar trend in unplanned take-back.

CONCLUSION

This is the first national study to specifically analyze the timing of take-back in the head and neck reconstruction population. These data highlight the importance of flap monitoring during the first 5 PODs, with ERAS pathway optimization aiming for discharge by the end of the first postoperative week.

Superficial Temporal Recipient Vessels for Craniofacial Microvascular Free-Flaps

The selection of recipient vessels for microvascular free-flaps is critical in craniofacial reconstruction. Especially the suitability of the superficial temporal vessels is questioned conflictingly in the literature. The aim of this study was to share our experience with microvascular craniofacial free-flap reconstruction and to evaluate a set of factors that are related to the recipient vessels and to determine how these factors influence flap survival. We conducted a retrospective analysis of 39 free-flaps for craniofacial reconstruction that were performed from 2006 until 2020 and evaluated the indication for microvascular reconstruction, recipient vessels, various factors related to the recipient vessels and complications. The most utilized recipient artery was the facial artery, selected in 20 patients followed by the superficial temporal artery selected in 12 patients. The most commonly used recipient vein was the facial vein used in 16 patients, followed by the superficial temporal vein selected in 10 patients and the external jugular vein in 6 patients. Total flap necrosis occurred in one patient. There was no statistically significant association between the selected recipient vessels and patient comorbidities, major and minor complications, revision of anastomosis or flap loss. The results of our study have demonstrated that the superficial temporal artery and vein show similar results when used for face and scalp reconstruction. Considering their technical and aesthetic advantages they may be the first choice recipient vessels in established free-flap treatment algorithms for craniofacial reconstruction.

Risk Factors for Free Flap Outcomes: A Retrospective Study of 318 Free Flaps for Head and Neck Defect Reconstruction

OBJECTIVES

This study was conducted to identify the risk factors for free flap outcomes in head and neck reconstruction.

METHODS

A retrospective review of 318 free flaps were used for head and neck reconstructions in 317 patients over seven years. The patient characteristics, surgical data, and flap outcomes were recorded. The impact of risk factors related on the outcomes of free flaps were analyzed using single and multivariate analysis.

RESULTS

For single factor analysis, 295 free flaps for the first reconstruction were included. Hypertension and the type of recipient vein are associated with venous thrombosis (P = .018, P = .047). Hypertension, type of free flap, recipient artery, and recipient vein were associated with the incidence of re-exploration (P = .009, P = .011, P = .017, P = .021). Hypertension had an obvious effect on the flap survival (P = .005). For multivariate analysis, hypertension (odds ratio = .166, 95% confidence interval: .043 - .636; P = .009) was a statistically significant risk factor for flap survival. For types of recipient artery and vein, selecting two venous anastomosis (one of IJVS and one of EJVS) had the minimum incidence of venous thrombosis (2.2%), and selecting facial artery, single vein (one of IJVS), and two veins (one of IJVS and one of EJVS) for anastomosis had lower incidence of re-exploration, which were 4.4%, 2.9%, and 6.0%, respectively (P < .05).

CONCLUSIONS

Risk factors as hypertension, type of free flap, recipient artery and vein should be paid more attention in the free flaps for head and neck reconstructions. We believe proper measures will lead to better results in head and neck reconstruction.

Primary radiotherapy and deep inferior epigastric perforator flap reconstruction for patients with breast cancer (PRADA): a multicentre, prospective, non-randomised, feasibility study

BACKGROUND

Radiotherapy before mastectomy and autologous free-flap breast reconstruction can avoid adverse radiation effects on healthy donor tissues and delays to adjuvant radiotherapy. However, evidence for this treatment sequence is sparse. We aimed to explore the feasibility of preoperative radiotherapy followed by skin-sparing mastectomy and deep inferior epigastric perforator (DIEP) flap reconstruction in patients with breast cancer requiring mastectomy.

METHODS

We conducted a prospective, non-randomised, feasibility study at two National Health Service trusts in the UK. Eligible patients were women aged older than 18 years with a laboratory diagnosis of primary breast cancer requiring mastectomy and post-mastectomy radiotherapy, who were suitable for DIEP flap reconstruction. Preoperative radiotherapy started 3-4 weeks after neoadjuvant chemotherapy and was delivered to the breast, plus regional nodes as required, at 40 Gy in 15 fractions (over 3 weeks) or 42·72 Gy in 16 fractions (over 3·2 weeks). Adverse skin radiation toxicity was assessed preoperatively using the Radiation Therapy Oncology Group toxicity grading system. Skin-sparing mastectomy and DIEP flap reconstruction were planned for 2-6 weeks after completion of preoperative radiotherapy. The primary endpoint was the proportion of open breast wounds greater than 1 cm width requiring a dressing at 4 weeks after surgery, assessed in all participants. This study is registered with ClinicalTrials.gov, NCT02771938, and is closed to recruitment.

FINDINGS

Between Jan 25, 2016, and Dec 11, 2017, 33 patients were enrolled. At 4 weeks after surgery, four (12·1%, 95% CI 3·4-28·2) of 33 patients had an open breast wound greater than 1 cm. One (3%) patient had confluent moist desquamation (grade 3). There were no serious treatment-related adverse events and no treatment-related deaths.

INTERPRETATION

Preoperative radiotherapy followed by skin-sparing mastectomy and immediate DIEP flap reconstruction is feasible and technically safe, with rates of breast open wounds similar to those reported with post-mastectomy radiotherapy. A randomised trial comparing preoperative radiotherapy with post-mastectomy radiotherapy is required to precisely determine and compare surgical, oncological, and breast reconstruction outcomes, including quality of life.

FUNDING

Cancer Research UK, National Institute for Health Research.

Using the DASH Questionnaire to Evaluate Donor Site Morbidity of the Serratus Anterior Free Flap in Head and Neck Reconstruction: A Multicenter Study

Objective: To evaluate donor site morbidity of the serratus anterior free flap (SAFF) in head and neck reconstruction. Methods: The Disabilities of the Arm, Shoulder and Hand (DASH) questionnaire (0 no disability to 100 most severe disability) was applied to 20 patients (M: 16; F: 4) who underwent ablative surgery and reconstruction of the head and neck using a SAFF. Applications, as well as the donor site, recipient site and flap-related complications, were evaluated. Results: SAFF was mainly used for tongue (n = 11; 55.0%) and pharyngeal reconstruction after a laryngopharyngectomy (n = 4; 20.0%). The majority of patients presented with stage IV disease (n = 12; 60%) and had undergone previous radiotherapy (n = 14; 70%). Our free flap survival rate was 88.9% and the pectoralis major muscle flap (PMMF) was used in 5 patients as a salvage option to reconstruct pharyngeal defects. The mean/median DASH score was 21.6/19.9 (healthy norm 10.1), indicating only mild to moderate disability. However, free flap failure and the additional harvest of PMMF multiplies donor site morbidity since it was associated with a 3- and 2.6-times higher DASH score (46.0 vs. 15.5; p = 0.039 and 39.9 vs. 15.47; p = 0.081). Conclusions: The SAFF represents a versatile flap for head and neck reconstruction with low donor site morbidity.

Free Flap Outcome in Irradiated Recipient Sites: A Systematic Review and Meta-analysis

The impact of previous radiotherapy on free flap outcome is still a subject of debate. Clinical investigations have come to divergent conclusions and the true effect of radiotherapy (XRT) on flap survival is not definitely known. Most studies investigating the factor often have their methodological limitations such as lack of statistical power as a consequence of the overall low failure rates together with few irradiated cases. This study will attempt to address the question whether previous radiotherapy is associated with a significantly higher incidence of flap failure or not.

Bone Union of Osseous Microvascular Free Tissue Transfer in Mandibular Reconstruction

Objectives

Osseous microvascular free tissue transfer (MFTT) is the gold standard for reconstruction for most segmental mandibulectomy defects. The most common osseous MFTT utilized in reconstruction is the fibular, scapular, and osteocutaneous radial forearm (OCRF) free flap. We evaluated postoperative bone union as well as clinical complications following MFTT and the impact of various patient and reconstructive characteristics, including type of osseous MFTT.

Study Design

Retrospective cohort study.

Setting

Tertiary care academic hospital.

Methods

This study examined patients who underwent osseous MFTT for mandibular defects from January 2017 to January 2019.

Results

An overall 144 osteotomies in 58 patients were evaluated. Of the 144 junctions, 28 (19.4%) showed radiographic nonunion. Patients who underwent preoperative (odds ratio [OR] = 0.30, P = .027) and postoperative (OR = 0.28, P = .003) radiation had a significantly lower bone union score. Time from surgery to postoperative imaging was associated with higher bone union scores (OR = 1.07, P = .024). When bone union scores were compared among types of MFTT, fibular (OR = 5.62, P = .008) and scapular (OR = 4.69, P = .043) MFTT had significantly higher scores than OCRF MFTT. Twelve (20.7%) patients had postoperative complications. There was no statistically significant correlation between clinical complications and various variables, including type of osseous MFTT.

Conclusion

Pre- and postoperative radiation and time from surgery have an impact on bone union. Regarding the type of MFTT, fibular and scapular MFTT appeared to have higher bone union when compared with OCRF. There was no impact of bone union or type of osseous MFTT on clinical complications.

Mandibular resection in patients with head and neck cancer: acute and long-term complications after reconstruction

BACKGROUND

The treatment of head and neck cancer is an intensive multimodal treatment that has a great impact on the individual patient.

AIMS/OBJECTIVES

This study aimed to evaluate acute and long-term complications associated with mandibular resections and reconstructions.

MATERIAL AND METHODS

We retrospectively retrieved data on complications and recurrences among patients that underwent mandibular resections and reconstructions for treating oral cavity cancer (n = 190 patients) and osteoradionecrosis (ORN, n = 72). Reconstructions included composite grafts (n = 177), soft tissue flaps (n = 61), or primary closure without any graft (n = 24).

RESULTS

Forty-two patients that underwent reconstructions with composite grafts displayed serious complications (Clavien-Dindo ≥ IIIa). The complication rates were similar between patients treated for oral cavity cancer and patients treated for ORN. Patients that underwent a primary closure without any graft, had a significantly lower risk of complications compared to patients that underwent the other treatments. After hospitalization, 181 patients (69%) had at least one complication.

CONCLUSIONS

A majority of patients undergoing resection and reconstruction due to oral cancer/ORN suffered from postoperative complications regardless of indication, comorbidity status or reconstruction technique. The risk of Clavien-Dindo grade IIIa-V events was significantly lower for patients treated with primary closure without grafts.

SIGNIFICANCE

The results from this study clarifies the importance of in-depth analyse prior to decision of treatment for patients with head and neck cancer.

Effect of preoperative radiation on free flap outcomes for head and neck reconstruction: An updated systematic review and meta-analysis

BACKGROUND

There is an ongoing debate about whether neoadjuvant radiation therapy is associated with higher rates of postoperative complications after head and neck reconstruction. Herle et al. conducted a systematic review in 2014 of 24 studies, finding higher complication rates in irradiated fields. We sought to perform an exhaustive updated systematic review and meta-analysis.

METHODS

We conducted an updated systematic review of the literature, as outlined in our protocol, which was registered on PROSPERO. Databases included Medline, Embase, Cochrane Central, and Web of Science. There were no limits placed on the date range, place of publication, or origin. Exclusion criteria included patients less than 18 years of age, studies with less than 20 participants (n < 20), case studies, skull base reconstructions, and local tissue rearrangements. The combined results of the studies and relative risks (RR) were calculated.

RESULTS

53 studies were included for analysis, including 5,086 free flaps in an irradiated field, and 9,110 free flaps in a non-irradiated field. Of the 53 studies, 21 studies overlapped with those discussed in Herle et al.'s study, with a total of 32 additional studies. Neoadjuvant radiation was found to be a statistically significant risk factor for postoperative complications (RR 1.579, P < 0.001), total flap failure (RR, 1.565; P < 0.001), and fistula (RR, 1.810; P < 0.001). Our work reaffirmed the findings of the Herle et al.

STUDY

CONCLUSION

Preoperative radiation was associated with a statistically significant increase in the risk of total flap failure, fistula, and total complications but not partial flap failure. These high-morbidity complications must be taken into consideration when determining which patients should receive neoadjuvant radiation therapy.

Recipient vessel selection for multiple free flap transfers in head and neck reconstruction at different periods

BACKGROUND

Treatment decisions can be challenging in patients undergoing multiple oropharyngeal microsurgical reconstructions at different periods by various causes. We, retrospectively, reviewed patients with at least three consecutive free flap reconstructions to determine the optimal strategy for selecting recipient vessels.

METHODS

Then, 36 patients (33 men and 3 women) who underwent at least 3 microsurgical reconstructions with a total of 51 free flap transfers for head and neck defects were included in this report. The most common reason for multiple microsurgical reconstructions was recurrent disease. For reconstructions, recipient vessel candidates on the same side of the head and neck were prioritized; if ipsilateral vessels were unavailable, contralateral recipient vessels, which might necessitate vein grafts, were used.

RESULTS

The most common reconstructions were anterolateral thigh flaps (19 cases). The most commonly used contralateral recipient vessels were the superior thyroid artery, facial artery, and external jugular vein. All vessel anastomoses were performed using the end-to-end method. Postoperative complications occurred at the sites of 26 free flap reconstructions. The overall flap reconstruction success rate in patients with at least three surgeries was 90.2%. The median follow-up duration was 25.8 months. During follow-up, 26 patients survived until the end of follow-up.

CONCLUSIONS

In patients undergoing multiple free flap reconstructions, recipient vessels on the ipsilateral side that have not been subjected to radiation should be selected first. Recipient vessels contralateral to the reconstruction side can then be selected; however, they may require vein grafts. Finally, distant healthy recipient vessels can be selected through vein grafting.

Radiation-Induced Soft Tissue Injuries in Patients With Advanced Mandibular Osteoradionecrosis: A Preliminary Evaluation and Management of Various Soft Tissue Problems Around Radiation-Induced Osteonecrosis Lesions

Objectives

Radiation-induced soft-tissue injuries (STIs) in mandibular osteoradionecrosis (ORN) are not well studied regarding their correlations with nearby bone lesions. The aim of this study is to investigate the severity of radiation-induced STIs in advanced mandibular ORN and its relationship with hard-tissue damage and postoperative outcomes.

Methods

A retrospective study was performed in our institution from January 2017 to December 2019. Aside from demographic factors, the associations between the triad ORN variables (irradiation doses, ORN stages, ORN sizes) and radiation-related STI factors, vascular characteristics, and postoperative functional recovery were assessed. In addition, the severity of STI was also compared with treatment outcomes. Such correlations were established via both univariate and multivariable analyses.

Results

A total number of 47 patients were included. The median follow-up reached 27 months. Nasopharyngeal cancer was the histology type among most patients (n = 21, 44.7%). The median irradiation doses reached 62 Gy (range, 40–110 Gy). For STI, the symptom scoring equaled an average of 5.4 (range from 1 to 12), indicative of the severity of STI problems. During preoperative MRI examinations, signs of hypertrophy or edema (n = 41, 87.2%) were frequently discerned. Most patients (n = 23, 48.9%) also had extensive muscular fibrosis and infection, which required further debridement and scar release. Surprisingly, most STI factors, except cervical fibrosis (p = 0.02), were not in parallel with the ORN levels. Even the intraoperative soft-tissue defect changes could not be extrapolated by the extent of ORN damage (p = 0.096). Regarding the outcomes, a low recurrence rate (n = 3, 6.9%) was reported. In terms of soft tissue-related factors, we found a strong correlation (p = 0.004) between symptom scores and recurrence. In addition, when taking trismus into consideration, both improvements in mouth-opening distance (p < 0.001) and facial contour changes (p = 0.004) were adversely affected. Correlations were also observed between the intraoperative soft-tissue defect changes and complications (p = 0.024), indicative of the importance of STI evaluation and management.

Conclusions

The coexistence of hard- and soft-tissue damage in radiation-induced advanced mandibular ORN patients reminds surgeons of the significance in assessing both aspects. It is necessary to take the same active measures to evaluate and repair both severe STIs and ORN bone lesions.

Flap Failure and Salvage in Head and Neck Reconstruction

With advanced head and neck ablative surgery comes the challenge to find an ideal reconstructive option that will optimize functional and aesthetic outcomes. Contemporary microvascular reconstructive surgery with free tissue transfer has become the standard for complex head and neck reconstruction. With continued refinements in surgical techniques, larger surgical volumes, and technological advancements, free flap success rates have exceeded 95%. Despite these high success rates, postoperative flap loss is a feared complication requiring the surgeon to be aware of potential options for successful salvage. The purpose of this article is to review free flap failure and ways to optimize surgical salvage in the scenario of flap compromise.

Flap demise reversed after central venous access device removal: A case report

Patients undergoing head and neck free flap reconstruction should be evaluated for radiation-induced venous stenosis and presence of central venous port as a potential risk for flap failure.

Controversies in free tissue transfer for head and neck cancer: A review of the literature

BACKGROUND

Microvascular free tissue transfer provides superior functional outcomes when reconstructing head and neck cancer defects. Careful patient selection and surgical planning is necessary to ensure success, as many preoperative, intraoperative, and postoperative patient and technical factors may affect outcome.

AIMS

To provide a concise, yet thorough, review of the current literature regarding free flap patient selection and management for the patient with head and neck.

MATERIALS AND METHODS

PubMed and Cochrane databases were queried for publications pertaining to free tissue transfer management and outcomes.

RESULTS

Malnutrition and tobacco use are modifiable patient factors that negatively impact surgical outcomes. The use of postoperative antiplatelet medications and perioperative antibiotics for greater than 24 hours have not been shown to improve outcomes, although the use of clindamycin alone has been shown to have a higher risk of flap failure. Liberal blood transfusion should be avoided due to higher risk of wound infection and medical complications.

DISCUSSION

There is a wide range of beliefs regarding proper management of patients undergoing free tissue transfer. While there is some data to support these practices, much of the data is conflicting and common practices are often continued out of habit or dogma.

CONCLUSION

Free flap reconstruction remains a highly successful surgery overall despite as many different approaches to patient care as there are free flap surgeons. Close patient monitoring remains a cornerstone of surgical success.

miR-29b Mediates the Chronic Inflammatory Response in Radiotherapy-Induced Vascular Disease

•

Radiotherapy is a powerful treatment strategy in patients with oncological diseases.

•

Radiation-induced vasculopathy can dose dependently increase the risk of ischemic cardiovascular diseases (e.g., myocardial infarction, heart failure, stroke).

•

The microRNA miR-29b is repressed in radiation-induced vasculopathy (human irradiated vs. nonirradiated tissue specimen, as well as in murine and cell culture models of irradiation).

•

Pentraxin-3 and dipeptidyl-peptidase 4 are the main downstream effectors of miR-29b in radiation-induced vasculopathy.

•

miR-29b mimics were able to limit pentraxin-3 and dipeptidyl-peptidase 4 levels in the irradiated vasculature (murine model) and to constrain the burden of vascular inflammation.

As a consequence of the success of present-day cancer treatment, radiotherapy-induced vascular disease is emerging. This disease is caused by chronic inflammatory activation and is likely orchestrated in part by microRNAs. In irradiated versus nonirradiated conduit arteries from patients receiving microvascular free tissue transfer reconstructions, irradiation resulted in down-regulation of miR-29b and up-regulation of miR-146b. miR-29b affected inflammation and adverse wound healing through its targets pentraxin-3 and dipeptidyl-peptidase 4. In vitro and in vivo, we showed that miR-29b overexpression therapy, through inhibition of pentraxin-3 and dipeptidyl-peptidase 4, could dampen the vascular inflammatory response.

Autologous fat transplantation alters gene expression patterns related to inflammation and hypoxia in the irradiated human breast

BACKGROUND

Radiation-induced fibrosis, an adverse effect of breast cancer treatment, is associated with functional and cosmetic impairment as well as surgical complications. Clinical reports suggest improvement following autologous fat transplantation, but the mechanisms underlying this effect are unknown. A global gene expression analysis was undertaken to identify genetic pathways dysregulated by radiation and evaluate the impact of autologous fat transplantation on gene expression.

METHODS

Adipose tissue biopsies were taken synchronously from irradiated and contralateral non-irradiated breasts, before and 1 year after autologous fat transplantation. Whole-genome gene expression analyses were performed, and Hallmark gene set analysis used to explore the effect of radiotherapy and autologous fat transplantation on gene expression.

RESULTS

Forty microarrays were analysed, using bilateral biopsies taken from ten patients before and after autologous fat transplantation. Forty-five pathways were identified among the 3000 most dysregulated transcripts after radiotherapy in irradiated compared with non-irradiated breast (P ≤ 0·023; false discovery rate (FDR) no higher than 0·026). After autologous fat transplantation, 575 of the 3000 genes were again altered. Thirteen pathways (P ≤ 0·013; FDR 0·050 or less) were identified; the top two canonical pathways were interferon-γ response and hypoxia. Correlative immunohistochemistry showed increased macrophage recruitment in irradiated tissues.

CONCLUSION

The present findings contribute to understanding of how autologous fat transplantation can ameliorate radiation-induced fibrosis. This further supports the use of autologous fat transplantation in the treatment of radiation-induced fibrosis. Surgical relevance Clinical studies have indicated that autologous fat transplantation (AFT) stimulates regression of chronic inflammation and fibrosis caused by radiotherapy in skin and subcutaneous fat. However, there is a paucity of biological evidence and the underlying processes are poorly understood. Human data are scarce, whereas experimental studies have focused mainly either on the effect of irradiation or AFT alone. The present results indicate that radiotherapy causes dysregulated gene expression in fibrosis-related pathways in adipose tissues in humans. They also show that AFT can cause a reversal of this, with several dysregulated genes returning to nearly normal expression levels. The study provides biological evidence for the impact of AFT on radiation-induced dysregulated gene expression in humans. It supports the use of AFT in the treatment of radiation-induced fibrosis, associated with severe morbidity and surgical challenges.

Upregulation of Plasminogen Activator Inhibitor-1 in Irradiated Recipient Arteries and Veins from Free Tissue Transfer Reconstruction in Cancer Patients

Background

Clinical studies have shown that radiotherapy can induce vascular disease at the site of exposure but is usually not clinically evident until years after treatment. We have studied irradiated human arteries and veins to better understand the underlying biology in search of future treatments. The aim was to investigate whether radiotherapy contributed to a sustained expression of plasminogen activator inhibitor-1 (PAI-1) in human arteries and veins.

Methods

Irradiated arteries and veins were harvested, together with unirradiated control vessels, from patients undergoing free tissue transfer reconstruction at a median time of 90 weeks [5–650] following radiation exposure. Differential gene expression of PAI-1 was analysed, together with immunohistochemistry (IHC) and immunofluorescence (IF).

Results

PAI-1 gene expression was increased in both arteries (p = 0.012) and veins (p < 0.001) in irradiated compared to unirradiated control vessels. IHC and IF indicated that cells expressing PAI-1 were located in the adventitia of both arteries and veins and colocalized with cells positive for CD68, CD45, and α-SMA in arteries and with CD45 and α-SMA in veins.

Conclusion

The current study shows a sustained upregulation of PAI-1 in both arteries and veins after exposure to ionizing radiation, indicating a chronic inflammation mainly in the adventitia. We believe that the results contribute to further understanding of radiation-induced vascular disease, where targeting PAI-1 may be a potential treatment.

Vascular architecture in free flaps: Analysis of vessel morphology and morphometry in murine free flaps

The aim of this study was to analyze the development of vascular architecture as well as vascular morphometry and morphology of anastomosed microvascular free flaps. Free pectoral skin flaps were raised in 25 rats and anastomosed to the femoral vessels in the groin region. CD31 immunohistology was performed after 3, 7 and 12 d (each 5 animals each) to analyze microvessel density (MVD), microvessel area (MVA) and microvessel size (MVS). Microvascular corrosion casting was performed after 7 and 12 d (5 animals each) to analyze vessel diameter (VD), intervascular distance (IVD), interbranching distance (IBD), and branching angle (BA). Further on, sprout and pillar density as hallmarks of sprouting and intussusceptive angiogenesis were analyzed. Pectoral skin isles from the contralateral side served as controls. A significantly increased MVD was found after 7 and 12 d (p each <0.001). MVA was significantly increased after 3, 7 and 12 d (p each <0.001) and a significantly increased MVS was analyzed after 3 and 7 d (p each <0.001). VD and IVD were significantly increased after 7 and 12 d (p each <0.001). For IBD, a significantly increase was measured after 7 d (p < 0.001). For IBA, sprout and pillar density, no significant differences were found (p each ≥0.05). Significant changes in the vascular architecture of free flaps after successful microvascular anastomosis were seen. Since there was no evidence for sprout and pillar formation within the free flaps, the increased MVD and flap revascularization might be induced by the receiving site.

Genetically modified lentiviruses that preserve microvascular function protect against late radiation damage in normal tissues

Improvements in cancer survival mean that long-term toxicities, which contribute to the morbidity of cancer survivorship, are being increasingly recognized. Late adverse effects (LAEs) in normal tissues after radiotherapy (RT) are characterized by vascular dysfunction and fibrosis causing volume loss and tissue contracture, for example, in the free flaps used for immediate breast reconstruction after mastectomy. We evaluated the efficacy of lentivirally delivered superoxide dismutase 2 (SOD2) overexpression and connective tissue growth factor (CTGF) knockdown by short hairpin RNA in reducing the severity of LAEs in an animal model of free flap LAEs. Vectors were delivered by intra-arterial injection, ex vivo, to target the vascular compartment. LVSOD2 and LVshCTGF monotherapy before irradiation resulted in preservation of flap volume or reduction in skin contracture, respectively. Flaps transduced with combination therapy experienced improvements in both volume loss and skin contracture. Both therapies reduced the fibrotic burden after irradiation. LAEs were associated with impaired vascular perfusion, loss of endothelial permeability, and stromal hypoxia, which were all reversed in the treatment model. Using a tumor recurrence model, we showed that SOD2 overexpression in normal tissues did not compromise the efficacy of RT against tumor cells but appeared to enhance it. LVSOD2 and LVshCTGF combination therapy by targeted, intravascular delivery reduced LAE severities in normal tissues without compromising the efficacy of RT and warrants translational evaluation as a free flap-targeted gene therapy.

The prosthetic rehabilitation of a patient with a lateral postsurgical defect using a 2-piece magnet-retained facial prosthesis: A clinical report

Nonsurgical prosthetic interventions are often proposed after repeated grafts have failed to restore irradiated facial defects. This report describes a facial prosthetic reconstruction following ablative surgery for a sizable facial tumor by using a novel custom-made magnet-bearing substructure, which connected with an exposed part of the mandibular reconstruction plate. The defect involved the entire left lower part of the face and angle of the mentum. This reconstructive technique, together with an added surface texture with hair-like silicone strands, effectively addressed the cosmetic needs of the patient. Magnetic anchorage to an exposed reconstruction plate could be considered an option for retaining facial prostheses. The biomechanical aspects of loading and retention should be addressed before considering this prosthetic option.

Improved Head and Neck Free Flap Outcome-Effects of a Treatment Protocol Adjustment from Pre- to Postoperative Radiotherapy

BACKGROUND

The impact of preoperative radiotherapy on microvascular reconstructive surgery outcome has been a subject of debate. However, data are conflicting and often dependent on local treatment protocols. We have studied the effects of radiotherapy in a unique, single-center setting where a treatment protocol change was undertaken from pre- to postoperative radiotherapy administration for microsurgical head and neck reconstructions.

METHODS

A cohort study was conducted for 200 consecutive head and neck free flap cases, where 100 were operated on before and 100 after the treatment protocol adjustment in 2006. Only direct cancer reconstructions were included. Complication rates of anastomosis-related (flap necrosis) and flap bed-related (infection, fistula, and wound dehiscence) complications were compared between irradiated and nonirradiated patients. A multivariate analysis was performed to correct for treatment period.

RESULTS

One hundred twenty-six patients had received radiotherapy before reconstruction due to cases of cancer recurrence. There were no significant differences in demographic data or risk factors between irradiated and nonirradiated cases. Irradiated cases had a higher rate of both flap loss (9.5% versus 1.4%; P = 0.034) and flap bed-related complications (29% versus 13%; P = 0.014). However, after multivariate analysis, there was only a significant relationship between preoperative irradiation and infection (odds ratio = 2.51; P = 0.033) and fistula formation (odds ratio = 3.13; P = 0.034).

CONCLUSIONS

The current single-center study clearly indicates that preoperative radiotherapy is a risk factor for both infection and fistula formation, most likely related to an impaired flap bed. We suggest postoperative radiotherapy administration whenever possible for oncological reasons, otherwise proper antibiotic cover and meticulous flap insetting to prevent radiation-related infection and fistula formation.

The utility of the musculocutaneous anterolateral thigh flap in pharyngolaryngeal reconstruction in the high-risk patient

BACKGROUND AND OBJECTIVES

Prior radiotherapy leads to increased wound complication rates for microsurgical reconstruction of pharyngolaryngeal (PL) defects. Incorporating vastus lateralis muscle together with anterolateral thigh flap (ALT) skin in defect reconstruction is useful in protecting vital structures and reinforcing irradiated neck skin and suture lines. This study shows the utility of the musculocutaneous ALT (MC ALT) in PL reconstruction in previously irradiated patients.

METHODS

A single-surgeon, retrospective chart review of all patients with defects of the PL region where an MC ALT was used for reconstruction from February 2014 to May 2016. The harvest of the MC ALT is described.

RESULTS

Thirteen consecutive patients underwent reconstruction with a MC ALT flap. All 13 patients had received previous radiotherapy. PL defects included five partial, five subtotal, and three total. There was a 100% flap survival rate with five early recipient site complications including three fistulas, one neck abscess, and one partial muscle necrosis. Three patients (23%) developed strictures requiring dilatation, two of whom had received post-reconstruction radiotherapy.

CONCLUSIONS

The use of the MC ALT for reconstruction of PL defects should be considered to mitigate the negative effects of prior irradiation and provide a back-up plan in instances where complications occur.

Free flap outcome of salvage surgery compared to primary surgery for head and neck defects: A propensity score analysis

OBJECTIVES

To compare free flap outcomes for head and neck defects between primary surgery and salvage surgery and identify factors affecting the outcomes in the two settings.

METHODS

A total of 225 patients (primary group, n=56; salvage group, n=169) were retrospectively identified. The salvage group was previously treated with radiotherapy, chemoradiation, surgery, or any combination of these treatments. Clinical data were retrieved and analyzed between the two groups to compare the incidence and contributing factors of flap-related complications and flap failure. A propensity score analysis with matching T stage, defect, and flap types was also performed for unbiased comparisons.

RESULTS

Flap-related complication rate was 22.2% in all patients. The salvage group showed higher rates of wound dehiscence than the primary group (3.6% in primary vs. 13.0% in salvage; p=0.04). Flap failures occurred in 10 patients (4.4%), including 3 (5.4%) in the primary group and 7 (4.1%) in the salvage group (p=0.71). Multivariate analysis showed no critical factor that influenced the occurrence of flap-related complications or flap failure, including surgery type (primary or salvage). In propensity score analysis, incidences and types of flap-related complications and flap failure were not statistically different between the two groups (primary and salvage).

CONCLUSIONS

Free flap reconstruction is a safe and reliable method to restore the ablative defects in previously irradiated or operated head and neck defects.

Identification of independent risk factors for flap failure: A retrospective analysis of 1530 free flaps for breast, head and neck and extremity reconstruction

Reconstructive microsurgery is a powerful method of treating various complex defects. However, flap loss remains a possibility, leading to additional surgery, hospitalisation and costs. Consequently, it is important to know which factors lead to an increased risk of flap failure, so that measures can be undertaken to reduce this risk. Therefore, we analysed our results over a 20-year period to identify risk factors for flap failure after breast, head and neck and extremity reconstruction. The medical files of all patients treated between 1992 and 2012 were reviewed. Patient characteristics, surgical data and post-operative complications were scored, and independent risk factors for flap loss were identified. Reconstruction with a total of 1530 free flaps was performed in 1247 patients. Partial and total flap loss occurred in 5.5% and 4.4% of all free flaps, respectively. In all flaps, signs of compromised flap circulation were a risk factor for flap failure. More specifically, the risk factors for flap failure in breast reconstruction were previous radiotherapy, venous anastomosis revision, gluteal artery perforator (GAP) flap choice and post-operative bleeding. In head and neck reconstruction, pulmonary co-morbidity and anastomosis to the lingual vein or superficial temporal artery were risk factors, whereas a radial forearm flap reduced the risk. In extremity reconstruction, diabetes, prolonged anaesthesia time and post-operative wound infection were risk factors. Independent pre-, intra- and post-operative risk factors for flap failure after microvascular breast, head and neck and extremity reconstruction were identified. These results may be used to improve patient counselling and to adjust treatment algorithms to further reduce the chance of flap failure.