A Current Review of Synthetic Meshes in Abdominal Wall Reconstruction:

Contemporary Abdominal Wall Reconstruction: Emerging Techniques and Trends

Abdominal wall reconstruction is a common and necessary surgery, two factors that drive innovation. This review article examines recent developments in ventral hernia repair including primary fascial closure, mesh selection between biologic, permanent synthetic, and biosynthetic meshes, component separation, and functional abdominal wall reconstruction from a plastic surgery perspective, exploring the full range of hernia repair's own reconstructive ladder. New materials and techniques are examined to explore the ever-increasing options available to surgeons who work within the sphere of ventral hernia repair and provide updates for evolving trends in the field.

Heavyweight versus non-heavyweight mesh in ventral hernia repair: a systematic review and meta-analysis

PURPOSE

There is considerable variability among surgeons regarding the type of mesh used in ventral hernia repair. There has been an increasing incidence of mesh fractures with lightweight (LW) and mediumweight (MW) meshes. However, HW mesh has been associated with a greater foreign body sensation and chronic pain. This meta-analysis aims to compare the outcomes of HW and non-heavyweight (NHW) meshes in ventral hernia repair.

METHODS

We systematically reviewed the PubMed, Embase, Cochrane, and Scopus databases to identify studies comparing HW with NHW meshes in hernia repair. Outcomes analyzed included hernia recurrence, seroma, hematoma, foreign body sensation, postoperative pain, and wound infection. We performed two subgroup analyses focusing on randomized controlled trials and open retromuscular repairs. Statistical analysis was performed using RevMan 5.4.

RESULTS

We screened 1704 studies. Nine studies were finally included in this meta-analysis and comprised 3001 patients from 4 RCTs and 5 non-randomized. The majority of patients (57.1%) underwent open retromuscular repair. HW mesh was significantly associated with increased in foreign body sensation (OR 3.71; 95% CI 1.40-9.84; p = 0.008), but there was no difference in other outcomes. In RCTs analysis, there was no difference between meshes. In open retromuscular repairs, HW mesh was associated with more seromas (OR 1.48; 95% CI 1.01-2.17; p = 0.05).

CONCLUSION

Our study found that HW mesh was associated with more foreign body sensation. Also, open retromuscular repairs analysis showed that HW was associated with more seromas. Further randomized studies are needed to understand better the role of HW mesh in ventral hernia repair.

Accelerated in vitro oxidative degradation testing of polypropylene surgical mesh

Polypropylene (PP) surgical mesh had reasonable success in repair of hernia and treatment of stress urinary incontinence (SUI); however, their use for the repair of pelvic organ prolapse (POP) resulted in highly variable results with lifelong complications in some patients. One of several factors that could be associated with mesh-related POP complications is changes in the properties of the implanted surgical mesh due to oxidative degradation of PP in vivo. Currently, there are no standardized in vitro bench testing methods available for assessing the susceptibility to oxidative degradation and estimating long-term in vivo stability of surgical mesh. In this work, we adapted a previously reported automated reactive accelerated aging (aRAA) system, which uses elevated temperatures and high concentrations of hydrogen peroxide (H2 O2 ), for accelerated bench-top oxidative degradation testing of PP surgical mesh. Since H2 O2 is highly unstable at elevated temperatures and for prolonged periods, the aRAA system involves a feedback loop based on electrochemical detection methods to maintain consistent H2 O2 concentration in test solutions. Four PP mesh samples with varying mesh knit designs, filament diameter, weight, and % porosity, were selected for testing using aRAA up to 4 weeks and characterized using thermal analysis, Fourier-transform infrared spectroscopy-attenuated total reflectance (FTIR-ATR) and scanning electron microscopy (SEM). Additionally, the oxidation index (OI) values were calculated based on the FTIR-ATR spectra to estimate the oxidative degradation and oxidation reaction kinetics of PP surgical mesh. The OI values and surface damage in the form of surface flaking, peeling, and formation of transverse cracks increased with aRAA aging time. The aRAA test method introduced here could be used to standardize the assessment of long-term stability of surgical mesh and may also be adopted for accelerated oxidative degradation testing of other polymer-based medical devices.

A novel self-gripping long-term resorbable mesh providing temporary support for open primary ventral and incisional hernia

A novel synthetic fully long-term resorbable self-gripping mesh has been recently developed to reinforce soft tissue where weakness exists during ventral hernia repair open procedures. This resorbable mesh is a macroporous, knitted, poly-L-lactide, poly-trimethylene carbonate copolymer monofilament mesh with the ProGrip™ technology, providing grips on one side of the mesh. A new poly-L-lactide, poly-trimethylene copolymer was developed to provide the required features for mechanical support during at least 20 weeks covering the critical healing period, including resistance to fatigue under cyclic loading conditions, as it occurs in patients. The yarns and mesh initial physical and biomechanical properties were characterized. Then, the mesh mechanical strength was evaluated over time. The mechanical properties of the proposed mesh were found to be above the generally recognized threshold value to mechanically support the repair site of a hernia over a 20-week period during in-vitro cyclic loading test. The mesh performance was evaluated in vivo using a published preclinical porcine model of hernia repair at 4-, 12- and 20-weeks post implantation. The burst strength of the hernia repair sites reinforced with the new mesh were higher at 4 & 12 weeks and comparable at 20 weeks to the one of the native abdominal walls. At all time points, the mesh was well tolerated with moderate inflammation and was fast integrated in the abdominal wall at 4 weeks. Particularly, the grips were nicely engulfed in the newly formed connective tissue. They must facilitate the anchoring of the mesh by their extension from the mesh and their mushroom shape. The preclinical data of the self-gripping resorbable mesh suggests that it has all the favorable characteristics for future clinical use during ventral hernia repair open procedures.

Efficient Decellularization of the Full-Thickness Rat-Derived Abdominal Wall to Produce Acellular Biologic Scaffolds for Tissue Reconstruction: Promising Evidence Acquired from In Vitro Results

BACKGROUND

Functional restoration of abdominal wall defects represents one of the fundamental challenges of reconstructive surgery. Synthetic grafts or crosslinked animal-derived biological grafts are characterized by significant adverse reactions, which are mostly observed after their implantation. The aim of this study was to evaluate the efficacy of the decellularization protocol to produce a completely acellular full-thickness abdominal wall scaffold.

METHODS

Full-thickness abdominal wall samples were harvested from Wistar rats and submitted to a three-cycle decellularization process. Histological, biochemical, and DNA quantification analyses were applied to evaluate the effect of the decellularization protocol. Mechanical testing and immunogenicity assessment were also performed.

RESULTS

Histological, biochemical, and DNA analysis results showed efficient decellularization of the abdominal wall samples after the third cycle. Decellularized abdominal wall scaffolds were characterized by good biochemical and mechanical properties.

CONCLUSION

The data presented herein confirm the effective production of a rat-derived full-thickness abdominal wall scaffold. Expanding this approach will allow the exploitation of the capacity of the proposed decellularization protocol in producing acellular abdominal wall scaffolds from larger animal models or human cadaveric donors. In this way, the utility of biological scaffolds with preserved in vivo remodeling properties may be one step closer to its application in clinical studies.

Polypropylene composite hernia mesh with anti-adhesion layer composed of PVA hydrogel and liposomes drug delivery system

Polypropylene (PP) mesh has been widely used in hernia repair as prosthesis material owing to its excellent balanced biocompatibility and mechanical properties. However, abdominal adhesion between the visceral and PP mesh is still a major problem. Therefore, anti-adhesive PP mesh was designed with poly(vinyl alcohol) (PVA) hydrogel and liposomes drug delivery system. First, PVA hydrogel coating was formed on the surface of PP mesh with freezing-thawing processing cycles (FTP). Subsequently, the lyophilized PVA₁₀-c-PP was immersed in rapamycin (RPM)-loaded liposome solution until swelling equilibrated to obtain the anti-adhesion mesh RPM@LPS/PVA₁₀-c-PP. It was demonstrated that the hydrogel coating can stably fix on the surface of PP mesh even after immersed in PBS solution at 37 °C or 40 °C for up to 30 days. In vitro cell tests revealed the excellent cytocompatibility and the potential to inhibit cell adhesion of the modified PP mesh. Moreover, the anti-adhesive effects of the RPM@LPS/PVA₁₀-c-PP mesh was evaluated through in vivo experiments. The RPM@LPS/PVA₁₀-c-PP mesh exhibited less adhesion than original PP mesh throughout the duration of implantation. At 30 days, the adhesion score of RPM@LPS/PVA₁₀-c-PP mesh was 1.37 ± 0.75, however the original PP was 3 ± 0.71. Furthermore, the results of H&E and Masson trichrome staining proved that the RPM@LPS/PVA₁₀-c-PP mesh showed slighter inflammation response and significant looser fibrous tissue surrounded the PP filaments as compared to the native PP. The current findings manifested that this type of RPM@LPS/PVA₁₀-c-PP might be a potential candidate for anti-adhesion treatment. DATA AVAILABILITY: Data will be made available on request.

Comparison of outcomes of ventral hernia repair using different meshes: a systematic review and network meta-analysis

PURPOSE

We conducted a network meta-analysis to evaluate potential differences in patient outcomes when different meshes, especially biological meshes, were used for ventral hernia repair.

METHODS

PubMed, Embase, Cochrane Library, and Clinical Trials.gov databases were searched for studies comparing biological meshes with biological or synthetic meshes for ventral hernia repair. The outcomes were hernia recurrence rate, surgical site infection, and seroma. We performed a two-step network meta-analysis to investigate the outcomes of several biological meshes: non-cross-linked human acellular dermal matrix (NCHADM), non-cross-linked porcine ADM (NCPADM), non-cross-linked bovine ADM (NCBADM), cross-linked porcine ADM (CPADM), and porcine small intestinal submucosa (PSIS).

RESULTS

From 6304 publications, 23 studies involving 2603 patients were finally included. We found no differences between meshes in recurrence at 1-year follow-up and in surgical site infection rate. NCBADM was associated with the lowest recurrence rate and the lowest surgical site infection rate. NCHADM implantation was associated with the lowest rate of seroma. PSIS was associated with a higher risk of seroma than NCHADM (pooled risk ratio 3.89, 95% confidence interval 1.13-13.39) and NCPADM (RR 3.42, 95% CI 1.29-9.06).

CONCLUSIONS

Our network meta-analysis found no differences in recurrence rate or surgical site infection among different biological meshes. The incidence of postoperative seroma was higher with PSIS than with acellular dermal matrices. We observed large heterogeneity in the studies of ventral hernia repair using biological meshes, and, therefore, well-designed randomized clinical trials are needed.

Giant Incisional Hernia Repair Using Open Intraperitoneal Dual Mesh

Aim

Giant incisional herniae are larger than 15 cm and are typically treated with an open approach. Our aim was to highlight the outcomes of treating giant incisional hernia using open intraperitoneal dual mesh.

Methods

Between January 2015 and December 2021, 25 patients with giant incisional hernias, where fascial defects were 15-30 cm, were evaluated retrospectively. Intraperitoneal dual mesh was used in all patients. The patients were evaluated in terms of age, gender, body mass index (BMI), previous abdominal surgeries, defect diameter, anesthesia method, length of hospital stay, drain application, complications, and recurrence.

Results

Eleven of the patients were male and 14 were female. The mean age was 62±13.5 years (29-82 years). The average BMI was 32 kg/m2 (20-52 kg/m2). The mean size of the fascial defect was 22±5.5 cm (15-30). The mean operation time was 90 minutes (70-130 minutes). Six patients had type I and II complications according to the Clavien-Dindo classification, specifically superficial skin infections, skin erosion, subcutaneous bleeding, and temporary ileus due to intestinal adhesion. During the average follow-up period of 36 months (6-70 months), no major complications were observed related to the recurrence and use of dual mesh.

Conclusion

In the treatment of giant incisional hernia, open intraperitoneal dual mesh application should be kept in mind as an effective treatment option with low complication and recurrence rates.

Anterolateral thigh flaps in closing large abdominal wall defect after the resection of mucinous adenocarcinoma: a case report

Background

It is a big challenge to repair a large abdominal wall defect after tumor resection, and en bloc resection with vascularized tissue reconstruction might be an alternative to achieve an improved survival for abdominal wall tumors.

Case presentation

A 45-year-old woman presented with a 1-year history of persistent abdominal pain of the right lower quadrant and a mass with dermal ulceration. An enhanced computed tomography scan and biopsy of the mass were performed to achieve the definite diagnosis of abdominal mucinous adenocarcinoma. After four courses of “FOLFOX” chemotherapy, the tumor grew to 6 × 5 cm during preoperative examination. Thereafter, we removed the tumor and involved tissues and organs and repaired the sizeable abdominal wall defect used by biological meshes and vascularized anterolateral thigh flaps. The patient suffered green drainage of 450 ml in the abdominal cavity and intestinal anastomotic fistula, for which she readmitted and recovered afterward.

Conclusions

Biological mesh combined with vascularized anterolateral thigh flaps could effectively repair the large abdominal wall defect and restore the biological function of the abdominal wall.

Delayed sequential abdominal wall closure in pediatric liver transplantation to overcome "large for size" scenarios

BACKGROUND

Primary abdominal wall closure after pediatric liver transplantation (PLT) is neither always possible nor advisable, given the graft-recipient size discrepancy and its potential large-for-size scenario. Our objective was to report the experience accumulated with delayed sequential closure (DSC) guided by Doppler ultrasound control.

METHODS

Retrospective analysis of DSC performed from 2013 to March 2020.

RESULTS

Twenty-seven DSC (26.5%) were identified out of 102 PLT. Transplant indications and type of grafts were similar among both groups. In patients with DSC, mean weight and GRWR were 9.4 ± 5.5 kg (3.1-26 kg) and 4.7 ± 2.4 (1.9-9.7), significantly lower and higher than the primary closure cohort, respectively. The median time to achieve definitive closure was 6 days (range 3-23 days), and the median number of procedures was 4 (range 2-9). Patients with DSC had longer overall PICU (22.5 ± 16.9 vs. 9.1 ± 9.7 days, p < .05) and hospital stay (33.4 ± 19.1 vs 23, 9 ± 19.8 days (p < .05). These differences are less remarkable if the analysis is performed in a subgroup of patients weighing less than 10 kg. Two patients presented vascular complications (7.4%) within DSC group. No differences were seen when comparing overall, 3-year graft and patient survival (96% and 96% in the DSC group).

CONCLUSIONS

DSC is a simple and safe technique to ensure satisfactory clinical outcomes to overcome "large for size" scenarios in PLT. In addition, we were able to avoid using a permanent biological material for closing the abdomen.

Latest Trends on the Attenuation of Systemic Foreign Body Response and Infectious Complications of Synthetic Hernia Meshes

Throughout the past few years, hernia incidence has remained at a high level worldwide, with more than 20 million people requiring hernia surgery each year. Synthetic hernia meshes play an important role, providing a microenvironment that attracts and harbors host cells and acting as a permanent roadmap for intact abdominal wall reconstruction. Nevertheless, it is still inevitable to cause not-so-trivial complications, especially chronic pain and adhesion. In long-term studies, it was found that the complications are mainly caused by excessive fibrosis from the foreign body reaction (FBR) and infection resulting from bacterial colonization. For a thorough understanding of their complex mechanism and providing a richer background for mesh development, herein, we discuss different clinical mesh products and explore the interactions between their structure and complications. We further explored progress in reducing mesh complications to provide varied strategies that are informative and instructive for mesh modification in different research directions. We hope that this work will spur hernia mesh designers to step up their efforts to develop more practical and accessible meshes by improving the physical structure and chemical properties of meshes to combat the increasing risk of adhesions, infections, and inflammatory reactions. We conclude that further work is needed to solve this pressing problem, especially in the analysis and functionalization of mesh materials, provided of course that the initial performance of the mesh is guaranteed.

Synthetic Mesh in Contaminated Abdominal Wall Surgery: Friend or Foe? A Literature Review

INTRODUCTION

The use of synthetic mesh in contaminated fields is controversial. In the last decade, published data have grown in this matter suggesting favorable outcomes. However, multiple variables and scenarios that influence the results still make difficult to obtain convincing recommendations.

METHODS

We performed a review of relevant available data in English regarding the use of synthetic meshes in contaminated abdominal wall surgery using the Medline database. Articles including patients undergoing ventral hernia in contaminated fields were included for analysis.

RESULTS

Most studies support the use of synthetic meshes for ventral hernia repair in contaminated fields, as they have shown lower recurrence rate and similar wound morbidity. Although no mesh seems ideal in this setting, most surgeons advocate for the use of reduced-in-weight polypropylene mesh. Sublay location of the prosthesis associated with complete fascial closure appears to offer better results in these patients. In addition, current evidence suggests that the use of prophylactic synthetic mesh when performing a stoma or for stoma reversal incisional hernias might be beneficial.

CONCLUSION

A better understanding of surgical site occurrences and its prevention, as well as the introduction of new reduced-in-weight meshes have allowed using synthetic meshes in a contaminated field. Although the use of mesh has indeed shown promising results in these patients, the surgical team should still balance pros and cons at the time of placing synthetics in contaminated fields.

Early Clinical and Patient-Reported Outcomes of a New Hybrid Mesh for Incisional Hernia Repair

INTRODUCTION

Consensus on the safety and efficacy of various types of mesh in reconstructing the abdomen has yet to be reached. Hybrid mesh products have been designed to address the need for a cost-effective mesh leveraging the tensile strength of a synthetic mesh while minimizing the prosthetic footprint within the abdominal wall through resorbable materials. In this study we evaluate early clinical outcomes and health related quality of life (HR-QOL) of a new Hybrid mesh, Synecor^TM, for Ventral Hernia Repair (VHR).

METHODS

Adult (>18 y old) patients undergoing VHR with Synecor^TM mesh by a single surgeon between 2017-2019 with ≥1-y follow-up were identified. We analyzed a composite of postoperative outcomes as well as the incidence of hernia recurrence, readmissions, mortality, and HR-QOL.

RESULTS

Thirty-five patients were included in our analysis with a median follow up of 2.1 y. The median age and BMI were 54.1 y and 33.2 kg/m², respectively. The rate of surgical site occurrences was 37.1%, with only one patient (2.9%) requiring surgical intervention. No patients developed a hernia recurrence. Overall HR-QOL improved significantly (preoperative mean 2.5 [SD 0.7] versus postoperative 3.4 [0.4]; P< 0.01), particularly in regards to pain, functional status, self-esteem and body image (all P < 0.05).

CONCLUSIONS

Abdominal reinforcement with Synecor^TM mesh at the time of VHR results in promising early recurrence rates, an acceptable safety risk profile, and an improvement in overall HR-QOL.

Transcriptome-targeted analysis of human peripheral blood-derived macrophages when cultured on biomaterial meshes

Surgical meshes are commonly used to repair defects and support soft tissues. Macrophages (Mφs) are critical cells in the wound healing process and are involved in the host response upon foreign biomaterials. There are various commercially available permanent and absorbable meshes used by surgeons for surgical interventions. Polypropylene (PP) meshes represent a permanent biomaterial that can elicit both inflammatory and anti-inflammatory responses. In contrast, poly-4-hydroxybutyrate (P4HB) based meshes are absorbable and linked to positive clinical outcomes but have a poorly characterized immune response. This study evaluated the in vitro targeted transcriptomic response of human Mφs seeded for 48 h on PP and P4HB surgical meshes. The in vitro measured response from human Mφs cultured on P4HB exhibited inflammatory and anti-inflammatory gene expression profiles typically associated with wound healing, which aligns with in vivo animal studies from literature. The work herein provides in vitro evidence for the early transcriptomic targeted signature of human Mφs upon two commonly used surgical meshes. The findings suggest a transition from an inflammatory to a non-inflammatory phenotype by P4HB as well as an upregulation of genes annotated under the pathogen response pathway.

Risk factors, outcomes, and complications associated with combined ventral hernia and enterocutaneous fistula single-staged abdominal wall reconstruction

PURPOSE

To compare two cohorts of patients; those with isolated ventral hernias (VH) and those with VH and enterocutaneous fistulas (ECF). Risk factors for surgical complications (including recurrent ECF) and outcomes during single-stage VH with ECF surgical reconstruction were analyzed.

METHODS

A retrospective review was performed from 2008 to 2019. We compared two cohorts of patients with single-stage VH repairs: (1) ventral hernia repair alone (hernia alone), and (2) combined VH repair and ECF repair (hernia plus ECF). Inclusion criteria were patients ≥ 18 years of age with pre-operative VH either with or without an ECF, who underwent open hernia repair and ECF repair in a single-stage operation, with a minimum follow-up of 12 months. Patient risk factors, operative characteristics, outcomes and surgical-site complications were compared using univariate and multivariate analyses.

RESULTS

We included 442 patients (hernia alone = 401; hernia plus ECF = 41) with a median follow-up of 22 months (12-96). Hernia plus ECF patients were more likely to have inflammatory bowel disease (IBD)(OR 4.4, 95% CI 1.1-17.5, p = 0.037), a history of abdominal wound infections (OR 3.4, 95% CI 1.5-7.9, p = 0.004), reoperations (OR 4.9, 95% CI 1.6-15.4, p = 0.006), superficial soft tissue infections (OR 2.5, 95% CI 1.1-6.1, p = 0.044) and hematomas (OR 8.4, 95% CI 1.2-58.8, p = 0.031), compared to hernia alone patients. ECF recurrence was associated with diabetes mellitus (DM) (n = 8, 73% vs. n = 6, 20%; p = 0.003) and surgical-site complications (n = 10, 91% vs. n = 16, 53%; p = 0.048), compared to ECF resolution.

CONCLUSION

Risk factors for developing ECF were IBD and history of abdominal wound infections. Single-staged combined ECF reconstruction was associated with reoperations, soft tissue infections and hematomas. DM and surgical-site complications were associated with ECF recurrence.

The Internal Oblique Muscle Flap with Synthetic Mesh Reinforcement for a Large, Contaminated Abdominal Wall Defect

We report a case of a large mediocaudal abdominal defect in contaminated circumstances with no residual rectus abdominis muscle that was reconstructed using an internal oblique muscle flap with large-pore polypropylene mesh reinforcement. The internal oblique muscle flap can reconstruct the lower abdominal midline without leaving any additional conspicuous scar. Previous studies showed that large-pore polypropylene mesh in contaminated wounds has a minimal difference in terms of infection rate, and less frequent occurrence of hernia, compared even with biological meshes. We believe that this method could be a strong and cosmetically satisfying option for large mediocaudal abdominal wall reconstruction.

Closing Contaminated Fascial Defects With Synthetic Mesh and a Vacuum-Assisted Closure Device

BACKGROUND

The use of synthetic mesh is considered too high risk, and therefore, not an option when closing a contaminated abdominal fascial defect. This study evaluated the clinical outcomes when using synthetic mesh combined with vacuum-assisted closure (VAC) dressing to close these facial defects.

MATERIALS AND METHODS

From 2010 to 2016, a retrospective review was performed, including 34 patients in a single rural trauma center who underwent a damage control laparotomy in the presence of a contaminated or infected field. Definitive abdominal closure with a bridging polypropylene mesh along with the application of a VAC dressing was done in all cases. Data collection included baseline demographics, operative indication, postoperative complications, mortality and length of follow up.

RESULTS

Median age of the patients was 67 y (IQR 40-87 y), with 22 (65%) being male at the time of operation. The median duration of clinical follow-up was 15.15 mo. The observed complications included three fistulas, two hernias, nine draining sinus tracts, and three mesh explanations with an overall complication rate of 41.1%. Although the absolute observed fistula rate was 8.8% (3 cases), the adjusted mesh-related fistulas formation rate after chart review was 0.0%. No mortalities were attributed directly to mesh-related complication.

CONCLUSIONS

This study found no mesh-related fistulas when using a synthetic mesh along with a VAC dressing for abdominal closure in a contaminated field. These results may provide a platform for further study regarding the safety of this technique.

Functional requirements for polymeric implant materials in head and neck surgery

BACKGROUND

The pharyngeal reconstruction is a challenging aspect after pharyngeal tumor resection. The pharyngeal passage has to be restored to enable oral alimentation and speech rehabilitation. Several techniques like local transposition of skin, mucosa and/or muscle, regional flaps and free vascularized flaps have been developed to reconstruct pharyngeal defects following surgery, in order to restore function and aesthetics. The reconstruction of the pharynx by degradable, multifunctional polymeric materials would be a novel therapeutical option in head and neck surgery.

MATERIALS AND METHODS

Samples of an ethylene-oxide sterilized polymer (diameter 10 mm, 200μm thick) were implanted for the reconstruction of a standardized defect of the gastric wall in rats in a prospective study. The stomach is a model for a "worst case" application site to test the stability of the implant material under extreme chemical, enzymatical, bacterial, and mechanical load.

RESULTS

Fundamental parameters investigated in this animal model were a local tight closure between the polymer and surrounding tissues, histological findings of tissue regeneration and systemic responses to inflammation. A tight anastomosis between the polymer and the adjacent stomach wall was found in all animals after polymer implantation (n = 42). Histologically, a regeneration with glandular epithelium was found in the polymer group. No differences in the systemic responses to inflammation were found between the polymer group (n = 42) and the control group (n = 21) with primary wound closure of the defect of the gastric wall.

CONCLUSIONS

A sufficient stability of the polymeric material is a requirement for the pharyngeal reconstruction with implant materials.

Polypropylene Mesh Complications in the Sublay Position After Abdominally Based Breast Reconstruction: Les complications des treillis de polypropylène en sous-couche après une reconstruction mammaire par voie abdominale

Introduction

Abdominal wall morbidity after microsurgical breast reconstruction is an important consideration for patients and surgeons. Previous studies are limited by multiple mesh locations or types. In this study, we evaluate specifically subfascial polypropylene mesh placement to determine a more definitive complication rate and basis for objective comparison.

Methods

A retrospective review was performed for patients undergoing microsurgical breast reconstruction at our institution by 3 surgeons from 2015 to 2018. All patients with sublay placement of polypropylene mesh were included. Patient demographics, medical comorbidities, type of reconstruction, and postoperative abdominal wall complications were recorded.

Results

A total of 114 flaps were performed on 81 patients who met the inclusion criteria. Of these, 48 were deep inferior epigastric artery (DIEP) flaps (42%), 43 were MS-2 TRAM flaps (37.8%), 20 were muscle sparing (MS-1) transverse rectus abdominus muscle (TRAM) flaps (17.5%), and 3 were free TRAM flaps (2.6%). Average follow-up was 392 days (range: 29-1191). Average body mass index was 30.7. No patients developed hernias. Two patients (2.5%) complained of post-operative bulges, neither of which required operative treatment. Two patients experienced superficial abdominal wall infection, one of which required admission and intravenous antibiotics. Ten patients (12.3%) had abdominal incision dehiscence, 3 of which required operative intervention. There were no cases of mesh exposure, contamination, or removal.

Conclusion

Polypropylene mesh is safe and effective, with subfascial placement resulting in low morbidity and low rates of bulge/hernia formation after microsurgical breast reconstruction. Consideration should be given to using polypropylene mesh for fascial repairs after microsurgical breast reconstruction, particularly in high-risk populations.

Outcome after pediatric liver transplantation for staged abdominal wall closure with use of biological mesh-Study with long-term follow-up

Abdominal wall closure after pediatric liver transplantation (pLT) in infants may be hampered by graft-to-recipient size discrepancy. Herein, we describe the use of a porcine dermal collagen acellular graft (PDCG) as a biological mesh (BM) for abdominal wall closure in pLT recipients. Patients <2 years of age, who underwent pLT from 2011 to 2014, were analyzed, divided into definite abdominal wall closure with and without implantation of a BM. Primary end-point was the occurrence of postoperative abdominal wall infection. Secondary end-points included 1- and 5-year patient and graft survival and the development of abdominal wall hernia. In five out of 21 pLT recipients (23.8%), direct abdominal wall closure was achieved, whereas 16 recipients (76.2%) received a BM. BM removal was necessary in one patient (6.3%) due to abdominal wall infection, whereas no abdominal wall infection occurred in the no-BM group. No significant differences between the two groups were observed for 1- and 5-year patient and graft survival. Two late abdominal wall hernias were observed in the BM group vs none in the no-BM group. Definite abdominal wall closure with a BM after pLT is feasible and safe when direct closure cannot be achieved with comparable postoperative patient and graft survival rates.