Cross-linked Porcine Dermal Collagen Research Articles

Porcine dermal collagen mesh (Permacol™) as a bioprosthesis in the ligation of intersphincteric tract (BioLIFT) procedure.

Ligation of intersphincteric tract (LIFT) is a sphincter-saving technique used to treat anal fistulas. Incorporation of a bioprosthesis in LIFT (BioLIFT) aims to improve healing. The use of cross-linked porcine dermal collagen mesh Permacol™ in BioLIFT has never been investigated. The aim of this study was to compare the healing rates and outcome of LIFT and BioLIFT for complex anal fistulas using the Permacol™ biological mesh. A retrospective analysis of all patients having LIFT or BioLIFT for complex fistulas from January 2010 to November 2019 was performed in a tertiary referral centre. Patient data from a prospectively collected database of all patients having LIFT or BioLIFT were analyzed. LIFT and BioLIFT were performed in 48 (82.8%) and 10 (17.2%) patients, respectively. All BioLIFT patients had previous interventions for their fistulas compared to 30 (62.5%) of patients who had LIFT, p = 0.023. The primary healing rate for LIFT was 87.5% (42/48) compared to 80% (8/10) in BioLIFT, (p = 0.42). Eight (13.8%) patients developed complications, 6 (12.5%) in the LIFT group vs 2 (20%) in the BioLIFT group (p = 0.62). On univariate analysis, the number of previous operations was predictive of complications (p = 0.03). BioLIFT was not associated with complication (OR = 1.75, 95% CI: 0.30-10.3, p = 0.54) or primary healing (OR = 0.57, 95% CI: 0.97-3.36, p = 0.54). There was no significant difference in recurrence (LIFT 12.5% vs BioLIFT 0%, p = 0.58). Kaplan-Meier analysis found no difference in time to recurrence between the two groups (p = 0.65). Permacol™ mesh in BioLIFT is feasible and achieves a high primary healing rate of 80%. Prospective evidence is needed to establish the benefits of BioLIFT and determine whether Permacol™ is superior to the non-cross-linked porcine submucosal mesh.

Indications and Outcomes of a Cross-Linked Porcine Dermal Collagen Mesh (Permacol) for Complex Abdominal Wall Reconstruction: A Multicenter Audit.

To reduce the occurrence of complications in the setting of high-risk patients with contaminated operative field, a wide range of biologic meshes has been developed. Yet, few series have reported outcomes after abdominal wall repair (AWR) using such meshes. Permacol is an acellular porcine dermal collagen matrix with a cross-linked pattern. This study reports short- and long-term outcomes after AWR for incisional hernia using Permacol. All consecutive patients undergoing single-stage open AWR using Permacol mesh at eight university hospitals were included. Mortality, complication and hernia recurrence rates were assessed. Independent risk factors for complications and hernia recurrence were identified with logistic regression and Fine and Gray analysis, respectively. Overall, 250 patients underwent single-stage AWR with Permacol. Nearly 80% had a VHWG grade 3 or 4 defect. In-hospital mortality and complication rates were 4.8% (n = 12) and 61.6% (n = 154), respectively. Reintervention for complications was required for 74 patients (29.6%). Mesh explantation rate was 4% (n = 10). Independent risk factors for complications were smoking, defect size and VHWG grade. After a mean follow-up time of 16.8months (± 18.1months), 63 (25.2%) experienced hernia recurrence. One-, 2- and 3-year RFS were 90%, 74% and 57%, respectively. Previous AWR, mesh location and the need for reintervention were independent predictors of hernia recurrence. Single-stage AWR is feasible using Permacol. Mortality and complication rates are high due to patients' comorbidities and the degree of contamination of the operative field. Given the observed recurrence rate, the benefit of biologics remains to be ascertained.

Final results of a European, multicentre, prospective, observational study of Permacol™ collagen paste injection for the treatment of anal fistula.

Permacol™ collagen paste (Permacol™ paste) is an acellular cross-linked porcine dermal collagen matrix suspension for use in soft-tissue repair. The use of Permacol™ paste in the filling of anorectal fistula tract is a new sphincter-preserving method for fistula repair. The MASERATI100 study was a prospective, observational clinical study with the objective to assess the efficacy of Permacol™ collagen paste for anal fistula repair in 100 patients. Patients (n=100) with anal fistula were treated, at 10 European surgical sites, with a sphincter-preserving technique using Permacol™ paste. Fistula healing was assessed at 1, 3, 6 and 12months post-treatment, with the primary end-point being healing at 6months. Faecal continence and patient satisfaction were surveyed at each follow-up; adverse events (AEs) were monitored throughout the follow-up. At 6months postsurgery, 56.7% of patients were healed and the percentage healed was largely maintained, with 53.5% healed at 12months. Regarding AEs, 29.0% of patients had at least one AE, and 16.0% of patients had one or more procedure-related AE. Most AEs reported were minor and similar to those commonly observed after fistula treatment, and the incidence of serious adverse events was low (4.0% of patients). Regardless of treatment outcome, 73.0% of patients were satisfied or very satisfied with the procedure. Permacol™ paste is a promising sphincter-preserving treatment for anal fistulae and has minimal adverse side-effects.

A prospective multicentre observational study of Permacol™ collagen paste for anorectal fistula: preliminary results

Permacol collagen paste (Permacol paste) is a new option for the treatment of anorectal fistula. It functions by filling the fistula tract with an acellular crosslinked porcine dermal collagen matrix suspension. The MASERATI 100 study group was set up to evaluate the clinical outcome of Permacol paste in the treatment of anorectal fistula. This paper reports the results from the initial 30 patients enrolled in the MASERATI 100 prospective, observational clinical trial. Patients (N = 30) with anal fistula presenting to 10 European academic surgical units were treated with a sphincter-preserving technique using Permacol paste. Fistula healing was assessed at 1, 3, 6 and 12 months after treatment, with the primary end-point of fistula healing at 6 months post-surgery. Faecal continence and patient satisfaction were recorded at each follow-up visit and adverse events were monitored throughout the follow-up. Of the 28 patients with data at 6 months post-surgery, 15 (54%) were healed, and the healing rate was maintained at 12 months. Healing after treatment with Permacol paste was similar for intersphincteric to transsphincteric fistulae and primary or recurrent fistulae. Only one patient exhibited an adverse event (perianal abscess) that was possibly related to the treatment. At the last outpatient visit, over 60% of patients were satisfied or very satisfied with the operation. Permacol paste is shown to be effective in treating primary and recurrent cryptoglandular anorectal fistula with minimal unwanted side effects.

Retro-rectus repair of complex incisional hernia leads to low recurrence rate.

To assess the outcome of retro-rectus repair of complex abdominal wall repair (CAWR) in a single institution in relation to the use of biologic and synthetic mesh. A retrospective review was undertaken of complex abdominal wall repairs performed by a single surgical team, assessing the outcome of the retro-rectus repair and factors affecting the outcome. Between 2007 and 2013, 57 (33 male) patients underwent CAWR retro-rectus repair. The material used was assessed as either synthetic or biologic (cross-linked porcine dermal collagen). The Ventral Hernia Working Group grades were similar between groups of patients having a repair with synthetic and biologic mesh. Median follow-up in the synthetic group was 18 months (1-80.5) and 18.4 months (0.5-70.7) in the biologic group. There was no statistical difference in seroma, wound infection or haematoma rates. No fistulae occurred in either group. Overall recurrence was 3.4% and there was no statistical difference between groups. The retro-rectus repair technique is associated with a low rate of recurrence and is now the technique of choice. The choice of material, biologic or synthetic, in Ventral Hernia Working Group grades 1-3 remains controversial.

Role of Permacol Injection in the Treatment of Patients With Fecal Incontinence.

See Article on Page 73-78 Fecal incontinence (FI) is defined as the uncontrolled passage of feces or gas over at least 1-month duration in an individual of at least 4 years of age who had previously achieved control [1,2,3,4]. Incontinence has a negative impact on self-esteem and quality of life (QoL) and may result in significant secondary morbidity, disability, and cost [1]. Prevalence rates vary widely depending on the method used for fecal incontinence examination and the target population examined, but, in general, they range between 1.4% and 18%. In institutionalized patients, however, incontinence may affect up to 50%, which is a frequent reason for transfer to nursing homes [2,3,4,5,6]. The Mature Woman's Health Study, which used Neilson data to survey women aged ≥45 years, indicated that nearly 20% of women have FI at least once per year and that 9.5% have at least 1 episode per month [7]. According to the recommended standard for the treatment of patients with FI specified by the American Society of Colon and Rectal Surgeons Clinical Practice Guideline, medical management is 1C, sphincter repair for external anal sphincter defects is 1B, biofeedback is 1B, and sacral neuromodulation is 1B as well. The recommended standard for injection of bulking agents is 2B, which is lower than other treatment methods [1]. Injection of bulking agents was first used on patients suffering from urinary incontinence, and the first report of such a method being used for anal incontinence was presented in 1993 when Shafik [8] injected polytetrafluoroethylene paste (Teflon, Dupont, Wilmington, DE, USA) into the anus to treat a patient with FI. An ideal bulking agent should be nonirritable, biocompatible, nonimmunogenic and durable. Other elements that must be considered when selecting a bulking agent are ease of implant, migration, inflammation reaction, and more [9]. Of the numerous bulking agents used, the main ones include bovine glutaraldehyde cross-linked collagen (Contigen, Bard Urological, Convington, GA, USA), autologous fat, and carbon-coated zirconium-oxide beads in water-based gel (Durasphere, Boston Scientific Corp., Boston, MA, USA) while dextranomer microspheres in nonanimal stabilized hyaluronic acid gel (Solesta, Oceana Therapeutics Inc., Edison. NJ, USA), porcine dermal collagen (Permacol, Covidien, Gosport, UK), polytetrafluoroethylene paste (Teflon, Dupont, Wilmington, DE, USA), polydimethylsiloxane elastomer in hydrogel carrier (PTQ, Uroplasty BU, Geleen, The Netherlands), synthetic calciumhydroxylapatite ceramic microspheres in an aqueous-based gel carrier (Coaptite, Bioform Medical Inc., San Mateo, CA, USA), and ethylene vinyl alcohol dissolved in dimethyl sulphoxide are also widely used. Newly created or enhanced bulking agents continue to be released into the market [9]. Permacol is cross-linked porcine dermal collagen. It has been designed to resist breakdown by collagenase in the body and maintain a long-standing increase in bulk. The product is biocompatible and once injected is incorporated into host tissue, with associated cellular and microvascular in growth. No evidence has been found for its being associated with irritancy or allergenicity [10,11]. Although the characteristics of Permacol are known, previous research about Permacol injection has shown that the number of patients with recurring symptoms of anal incontinence increases in as little as 6 weeks, which leads one to question the durability of Permacol [12]. In other words, the conditions just after an injection are not maintained, but rather the bulking agent is absorbed by surrounding tissues, often leading to the need for another injection. This research lacks objective data on, for example, anal pressure as it merely assessed patients' conditions centered on an evaluation of QoL. Also, the number of target patients is small while that of tracked and observed patients is even smaller. Six of the 9 research papers on anal manometry presented in this systematic journal review failed to show meaningful changes in the mean resting pressure [13]. Similarly, this research does not show a significant difference from previous research results [14]. Despite the relatively short period of tracking and observation, the QoL showed a meaningful change, which is a result similar to those of other studies done in the past. With the injection of bulking agents, the treatment method normally used in urology clinics has been applied to patients with anal incontinence. The action mechanisms are similar; however, a greater amount of inflating agent is used, and the procedure is less likely to be effective.

Onlay parastomal hernia repair with cross-linked porcine dermal collagen biologic mesh: long-term results.

The optimal technique and mesh type for parastomal hernia repair have yet to be ascertained. Biologic meshes have been advocated in parastomal hernia repair due to purported resistance to infection in contaminated fields. The aim of this study was to evaluate the effectiveness of additionally cross-linked acellular porcine dermal collagen mesh (Permacol) for onlay parastomal hernia repair. A retrospective review of case notes, and abdominal CT scans when available, was performed for consecutive patients who had a parastomal hernia repaired between January 2007 and May 2010. All hernias were repaired with onlay placement of the biologic mesh. Hernias were classified according to the Moreno-Matias classification where CT scans were available. Over a 34-month period, 30 consecutive patients, median age 74 years, 17 female, underwent parastomal hernia repair using onlay biologic mesh. There were 23 paracolostomy and seven paraileostomy hernias. The hernia was primary in 26 patients. Pre-operative CT scans were available in 18 patients (Moreno-Matias Type 1 = 1, Type 2 = 4, Type 3 = 13). There was one perioperative death, and 29 patients were available for follow-up, and median duration of follow-up (either CT or clinical) was 36 months (range 3-79). Twenty-six patients developed recurrence of the parastomal hernia (89.6%), and median time to recurrence was 10 months (range 3-72),with Moreno-Matias Type 1 = 0, Type 2 = 4, Type 3 = 14, unknown = 8. Fifteen out of 26 patients have had repairs of the recurrence using a variety of techniques. Of these, 10 patients have had further recurrence. Onlay repair of parastomal hernia with cross-linked porcine dermal collagen biologic mesh reinforcement has poor long-term outcomes with unacceptably high recurrence rates and should not be performed.

Rectopexy for Rectal Prolapse.

Ventral mesh rectopexy (VMR) is a recognized treatment for posterior compartment pelvic organ prolapse (POP). The aim of this review is to provide a synopsis of the evidence for biological mesh use in VMR, the most widely recognized surgical technique for posterior compartment POP. A systematic search of PubMed was conducted using the search terms "VMR," "ventral mesh rectopexy," or "mesh rectopexy." Six studies were identified. About 268/324 patients underwent ventral rectopexy using biological mesh with a further 6 patients having a combination of synthetic and biological mesh. Recurrence was reported in 20 patients; however, 6 were from studies where data on biological mesh could not be extracted. There are no RCTs in VMR surgery and no studies have directly compared types of biological mesh. Cross-linked porcine dermal collagen is the most commonly used mesh and has not been associated with mesh erosion, infection, or fistulation in this review. The level of evidence available on the use of biological mesh in VMR is of low quality (level 4). Ventral mesh rectopexy has become prevalent for posterior compartment POP. The evidence base for its implementation is not strong and the quality of evidence to inform choice of mesh is poor.

PWE-393 Reconstruction of the pelvic floor after abdominoperineal excision

Introduction Extralevator abdominoperineal excision (ELAPE) involves the en bloc excision of the levator muscles and the rectum and the wider excision can increase morbidity and wound complications tthat will require some form of perineal reconstruction. The aim of this review is to provide an overview of the evidence for the use of biological mesh in the reconstruction of the pelvic floor after abdominoperineal excision. Method A systematic search of PubMed was conducted using the search terms ‘ELAPE’, ‘extralevator abdominoperineal excision of rectum’ or ‘extralevator abdominoperineal resection’ . The search yielded 17 studies for analysis after inclusion and exclusion criteria were applied. Results There were a total of 1055 patients across 17 studies. A biological mesh was used in perineal reconstruction in 463 patients with 206 patients using cross-linked porcine dermal collagen (PermacolTM), 44 using porcine intestinal submucosa (Surgisis©), 136 using human acellular dermal matrix (HADM) and 9 using a combination of PermacolTM and Surgisis©. Two studies did not specify the type of biological mesh used. There were 41 perineal hernias reported but rates were not consistently reported in all studies. The most common complications were perineal wound infection and perineal pain. However, there are no standardised measures for reporting perineal outcomes following ELAPE. There are very few studies comparing the use of biological mesh for perineal reconstruction for ELAPE. Two case series compared biological mesh with myocutaneous flaps and one series compared laparoscopic ELAPE with laparoscopic and open APER. Only one RCT was identified that compared patients undergoing ELAPE with perineal reconstruction using a biological mesh, with patients undergoing a conventional APER with no mesh. There was no significant difference in perineal hernia rates or perineal wound infections between the two groups although there were fewer positive circumferential resection margins in the ELAPE group. Conclusion The literature suggests that perineal closure using a biological mesh produces wound infection and complication rates that are comparable to other methods of reconstruction such as myocutaneous flaps. Biological mesh-assisted perineal reconstruction is a promising technique to improve wound healing but the results from high-quality prospective RCTs are required or national/international collaborative audits using statistical process control as a methodology of assessment of improvement. Disclosure of interest None Declared.

PTU-245 Rectopexy for rectal prolapse

Introduction Ventral mesh rectopexy (VMR) is a recognised treatment for posterior compartment pelvic organ prolapse (POP). A variety of synthetic meshes have been used for a wide range of POP surgery but there have been reports of high rates of pelvis sepsis, as well as concerns regarding mesh erosion, dyspareunia, fistulation and stricturing. It has been postulated that biological mesh may cause fewer complications in comparison to synthetic mesh in certain high-risk circumstances. The aim of this review is to provide a synopsis of the evidence for biologic mesh use in VMR, the most widely recognised surgical technique for posterior compartment POP. Method A systematic search of PubMed was conducted using the search terms ‘VMR’, ‘ventral mesh rectopexy’ or ‘mesh rectopexy’. Inclusion criteria were studies that described a ventral rectopexy using a biological mesh in either an open or laparoscopic technique. Studies were excluded if only synthetic mesh was used or if there was no mention of a mesh. Furthermore, studies on patients under the age of 18 were excluded as well as non-English language studies, technical tips or duplicates series from the same research group. Overall, the search yielded 6 studies for analysis after the exclusion of review articles. Results From 6 case series, 268/324 patients underwent ventral rectopexy using biological mesh with a further 6 patients having a combination of synthetic mesh and biological mesh. Overall, 155 patients underwent VMR using additionally cross-linked porcine dermal collagen (PermacolTM or PelvicolTM) and 89 using porcine intestinal submucosa (Surgisis©). Recurrence was reported in 20 patients; however, 6 of these were from studies where data on biological mesh could not be extracted. One study did not report recurrence. There are no randomised controlled trials in VMR surgery generally and no studies have directly compared types of biologic mesh e.g. cross-linked vs. non-cross-linked. Cross-linked porcine dermal collagen is the most commonly used mesh and has not been associated with mesh erosion, infection or fistulation in this current review. The level of evidence available on the use of biologic mesh in VMR is of low quality (level 4). Conclusion VMR has become prevalent for posterior compartment POP. The evidence base for its implementation is not strong and the quality of evidence to inform choice of mesh is poor. Disclosure of interest None Declared.

PTU-246 Augmentation of a sphincter repair

Introduction Faecal incontinence (FI) affects between 1–10% of adults in varying degrees. Current epidemiological studies have shown that up to 1% of adults have regular episodes of faecal incontinence that adversely impacts their quality of life. A variety of synthetic and biological agents have been used for both overlapping sphincter repair (OSR) and as an anal bulking agent. The aim of this review is to provide an overview of the use of biological materials in the augmentation of the sphincter repair. Method A systematic search of PubMed was conducted using the search terms ‘anal bulking agents’, ‘anal sphincter repair’ or ‘overlapping sphincter repair’. Studies that utilised biological material for either sphincter repair or as a bulking agent were included. Overall, 5 studies were indentified for analysis after inclusion and exclusion criteria were applied. Results There were 3 studies with 127 patients of which 122 underwent anal bulking with a biological agent. 105 patients received a cross-linked porcine dermal collagen in the form of PermacolTM and a further 17 received Glutaraldehyde cross-linked (GAX) collagen, a highly purified bovine dermal collagen. Anorectal physiology was carried out in 27 patients and demonstrated deterioration in maximum resting pressure, and no significant change in maximum squeeze increment. Quality of life scores such as St Mark’s incontinence score, SF-36 and the Cleveland Clinic Florida Incontinence Score (CCFIS) demonstrated an improvement in scores at 6 weeks and 6 months, but this had deteriorated at 12 month follow up. There were no complications reported. 10 patients received a cross-linked porcine dermal collagen (PermacolTM) for OSR and 13 patients received porcine intestinal submucosa (Surgisis©) to carry out an anal encirclement procedure. Improvements in Faecal Incontinence Severity Index (FISI), CCFIS and two subscales of Faecal Incontinence Quality of Life (FIQL) (coping/behaviour and embarrassment) were observed in the group of patients undergoing OSR. Furthermore, the FISI, Wexner score and all components of FIQL score (lifestyle, coping/behaviour, depression and embarrassment) showed an improvement following anal encirclement using biological material. Incontinence episodes decreased to an average of one per week from 8 to 10 preoperatively and no complications were reported. Conclusion Sphincter augmentation with biological material has demonstrated significantimprovement in continence and quality of life scores in the short term compared to traditional repair. Long-term studies are necessary to determine if this effect is sustained. Disclosure of interest None Declared.

Diaphragmatic crural augmentation utilising cross-linked porcine dermal collagen biologic mesh (Permacol) in the repair of large and complex para-oesophageal herniation: a retrospective cohort study.

To evaluate the safety, efficacy and durability of selective integration of porcine dermal collagen (Permacol) biologic mesh for crural re-construction in large or complex para-oesophageal hernia surgery. Surgical repair of para-oesophageal herniation has been associated with high rates of failure. The utilisation of prosthetic mesh is controversial with complications including erosion and fistulation. Long-term outcomes for biologic mesh crural augmentation are unclear. A retrospective analysis of patients who underwent a biologic mesh (Permacol) augmented cruroplasty in the repair of large and/or complex para-oesophageal hernia was performed utilising the prospectively maintained oesophago-gastric database at the Royal Devon and Exeter Hospital between October 2004 and January 2013. This technique was selectively used for patients where the lateral extent of the diaphragmatic-crural defect prevented the fashioning of a sound, tension-free repair with sutures alone, or previous surgery had failed. Successful outcome was defined by resolution of symptoms and structural integrity of the repair. Fifty one procedures were performed on 49 patients (15 male), median age 75 (range 25-91). Post-operative morbidity included 2 (3.9%) oesophageal injuries managed conservatively, and 2 (3.9%) patients who suffered early repair breakdown requiring immediate surgical re-intervention. Four patients (8%) required endoscopic dilatation due to dysphagia, one (2%) in the early post-operative phase. The median follow-up was 36 months (range 6-105). All patients reported initial symptomatic resolution. Two patients (4%) were demonstrated to have breakdown of their repair during the follow-up period, both of whom underwent revision mesh-augmented surgery and are re-incorporated in this series. Late-onset dysphagia in two (4%) patients may be mesh-related, but no other complications were observed and a Kaplan-Meier analysis of this series predicts a symptom-free rate of approximately 94% at 5 years. The selective integration of biologic mesh to augment the crural repair in para-oesophageal hernia with extensive diaphragmatic defects appears to be safe, effective and infers the potential of long-term satisfactory outcomes.

Biopsies of Permacol™ implant in humans after use in abdominal wall repair: histological and immunohistochemical analysis

Permacol™ biological implant is a cross-linked porcine dermal collagen biomaterial that has been successfully used in abdominal wall repair. The purpose of this study is to examine biopsies of the implant after use in abdominal wall hernia repair and demonstrate its histological and immunohistochemical characteristics in vivo. Three male patients, ranging in age from 61 to 76 years, underwent biopsy of the implant and surrounding abdominal wall tissue at 16, 36, and 60 months after implantation. At 16 months, the implant demonstrated excellent tissue integration, cellular and neovascular response, and remodeling. The implant–host tissue interface showed seamless integration with no fibrosis. Tissue ingrowth into the material, new blood vessel formation, and remodeling of the host–tissue interface were observed. At approximately 36 months, organized remodeling of the implant into functional, predominately host tissue was generally seen. At more than 60 months, macroscopic and histological characteristics resembled functional human tissue with immunohistochemical evidence of the residual presence of porcine collagen. Permacol™ implant supports controlled and natural long-term remodeling into normal, functional host tissue.

Thoracic Wall Reconstruction with Acellular Porcine Dermal Collagen Matrix.

Major thoracic wall resections require the implantation of foreign materials for reconstruction and stabilization. Recently, biological collagen matrixes have emerged as an alternative to the routinely used synthetic materials. Retrospectively, we analyzed our initial experience of chest wall reconstruction on large defects using a cross-linked porcine dermal acellular collagen matrix mesh with a thickness of 1.5 mm. Six sarcoma patients with a mean age of 46 (22-66) years underwent chest wall resections. Complete thoracic wall defects (mean area 149 cm2) ranged from 8 × 10 to 15 × 20 cm in size. In the majority of cases, only mobilized subcutaneous tissue and skin were used for soft-tissue coverage of the implanted porcine collagen matrix patches. Implantation and postoperative courses were uneventful in all patients. No local infections or wound healing problems occurred. The collagen material resulted in durable and good to excellent chest wall stability in clinical follow-ups, and on computed tomography scans spanning over 3.5 years. Histological examination showed integration, neovascularization, and long-term persistence of the collagen matrix on late reoperation of one patient. Acellular porcine dermal collagen matrix is a feasible and reliable biological patch material for reconstruction of the thoracic wall. Excellent wound healing and long-term stability are achieved even in large defects or complete sternal replacements.

The use of Permacol for the reconstruction of a complex thoraco-abdominal wall defect from a recurrent leiomyosarcoma

Complex thoraco-abdominal wall defects following tumor resection create a unique reconstructive challenge, which centers on anatomically re-establishing the thoracic and abdominal compartments to prevent visceral herniation. Autologous tissue may not be available or adequate to reconstruct these defects; therefore, the use of alternative options, such as non-autologous material, is often necessary. To our knowledge, very little has been described about the use of biologic mesh for the reconstruction of large thoracic defects. We present a review of the literature and present a novel approach to address a difficult defect with the use of cross-linked porcine dermal collagen (Permacol) to bridge a thoraco-abdominal defect while stabilizing the diaphragm. Level of Evidence: Level V, therapeutic study.

Transthoracic repair of an incarcerated diaphragmatic hernia using hexamethylene diisocyanate cross-linked porcine dermal collagen (Permacol)

It is the general surgeon who commonly repairs paraesophageal hernias nowadays, and they are repaired laparoscopically, making the performance of thoracotomy relatively rare. Whether to use prosthetic materials to repair the hiatus is still under debate, as is the question of which material to use, if any. We report a case of a 38-year-old man who had a large, incarcerated paraesophageal hernia. He had a past history of extensive abdominal surgery for exomphalos, which rendered any abdominal surgical approach a high-risk procedure. We therefore decided to proceed with thoracotomy and repair of the hiatus with hexamethylene diisocyanate (HMDI) cross-linked porcine dermal collagen. He made a good recovery with no complications.

Parastomal hernia repair outcomes in relation to stoma site with diisocyanate cross-linked acellular porcine dermal collagen mesh

Biologic meshes are increasingly used in parastomal hernia repair. This study evaluates the efficacy and safety of diisocyanate cross-linked acellular porcine dermal collagen mesh for parastomal hernia repair, with particular reference to the relationship of the stoma site to the rectus sheath. Hernias were repaired via a lateral approach, with onlay placement of the biologic mesh. A retrospective case note review and analysis of clinical outcomes was performed. The relationship of the stoma to the rectus sheath was determined by abdominal computed tomography (CT) and intraoperative findings. Over a 16-month period, 27 consecutive patients, median age 72 years, underwent parastomal hernia repair utilising onlay biologic mesh to reinforce the external oblique aponeurosis. There were 20 paracolostomy and seven paraileostomy hernias. Eleven stomas passed through the rectus sheath and 16 were lateral to it. Recurrences occurred in 3 of 11 stomas within and 12 of 16 stomas lateral to the rectus sheath (P = 0.022). The median time to recurrence was 10.1 months. The median follow up of patients without recurrence was 16.6 months (range 0.2-39.3). There was one perioperative death. One patient developed a superficial post-operative abscess that was managed conservatively, but there were no complications related to the biologic mesh and no mesh required removal. For parastomal hernias within the rectus sheath, diisocyanate cross-linked porcine dermal collagen mesh onlay repair gives good results and is safe to use. Repair of a parastomal hernia where the stoma is lateral to the rectus sheath has a significantly higher risk of recurrence and is not recommended.

Comparison of collagen scaffold tubes for possible esophagus organ tissue engineering applications: In-situ omental implantation study in an ovine model

BACKGROUND: Esophagus tissue engineering requires optimal scaffolds that can support the implanted cells and integrate with the implanted tissue. METHODS: Four collagen scaffolds were investigated in-situ in an ovine model after 8 weeks of omental implantation to assess their suitability with regards to integration and cellular infiltration for esophagus organ tissue engineering: (a) Acellular bovine pericardial collagen (BPC), (b) Acellular cross-linked (HDMI hexamethylene diisocyanate) porcine dermal collagen (PDC), (c) Porcine porous collagen (PPC) and (d) Bovine tendon dual-layered (type-1) collagen (DLC). RESULTS: BPC demonstrated minimal integration with minimal cellular infiltration. PDC was inert to both integration and cellular infiltration. PPC enabled integration to omental tissue; however, demonstrated minimal cellular infiltration. DLC exhibited both omental integration and cellular infiltration. CONCLUSION: DLC has close to ideal properties for application in esophagus tissue engineering. BPC and PPC could have limited application in esophagus tissue engineering whereas PDC has been found to be unsuitable.

Tie Hard 2- An in-Vitro Comparison of First Throw Tension Holding In Twisted v Straight-First Throws; Using Polyglycolic acid (Dexon S), Polyglactin 910 (Coated Vicryl)

Objective: To compare the first throw tension holding properties of twisted versus straight first throws in two commonly used Oculoplastic braided absorbable sutures.Design: An in-vitro experimental model.Methods: Variable loads were applied to the first double throw of a surgical knot – either in straight-line configuration or twisting the knot using both 6/0 Polyglycolic acid (Dexon S) and 6/0 Polyglactin 910 (Coated Vicryl). Each suture was tested to the point of knot slipping and the critical tension recorded. Two variations of the experiment were undertaken: Experiment 1 – two metal loops were brought together by the test suture, experiment 2 – two strips of tissue (Permacol - cross-linked porcine dermal collagen) were brought together by the test suture.Results: Experiment 1 straight: Polyglycolic acid 12.2g (11-13.5), Polyglactin-910 2.5 g (2.5- no range). Experiment 1 twisted: Polyglycolic acid 13.33 g (10–15), Polyglactin 910 3 g (2–5). Experiment 2 straight: Polyglycolic acid 33g (30-35), Polyglactin 910 25g (25 – no range). Experiment 2 twisted: Polyglycolic acid 35 (30-40), Polyglactin 910 25g (20–30).Conclusions: Twisting the suture adds only a modest increase in first throw knot security. Polyglycolic acid (Dexon S) braided absorbable suture has significantly better first throw knot security when compared with Polyglactin-910 (coated Vicryl). This is an important property when suturing tissues under tension as it minimises slippage before the locking throw is tied.

Parastomal hernia repair using cross-linked porcine dermis: Report of a case

Parastomal hernia is not an uncommon complication after colostomy or ileostomy formation, but it may have serious consequences, such as intestinal obstruction and strangulation. Thus, the surgeon must repair the parastomal hernia using a technique that minimizes the chance of recurrence and complications. This case report describes a novel method of parastomal hernia repair using cross-linked acellular porcine dermal collagen matrix, a new biological material suitable for hernia repair.