Mesh shrinkage depends on mesh properties and anchoring device: an experimental long-term study in sheep

Assessment of mesh shrinkage using fibroblast-populated collagen matrices: a proof of concept for in vitro hernia mesh testing

PURPOSE

This study uses free-floating contractile fibroblast-populated collagen matrices (FPCMs) to test the shrinkage of different hernia mesh products. We hope to present this model as a proof of concept for the development of in vitro hernia mesh testing-a novel technology with interesting potential.

METHODS

FPCMs were formed by seeding Human Dermal Fibroblasts into collagen gels. FPCMs were seeded with three different cell densities and cast at a volume of 500 μl into 24-well plates. Five different mesh products were embedded within the collagen constructs. Gels were left to float freely within culture media and contract over 5 days. Photographs were taken daily and the area of the collagen gel and mesh were measured. Media samples were taken at days 2 and 4 for the purposes of measuring MMP-9 release. After 5 days, dehydrated FPCMs were also examined under light and fluorescence microscopy to assess cell morphology.

RESULTS

Two mesh products-the mosquito net and large pore lightweight mesh were found to shrink notably more than others. This pattern persisted across all three cell densities. There were no appreciable differences observed in MMP-9 release between products.

CONCLUSIONS

This study has successfully demonstrated that commercial mesh products can be successfully integrated into free-floating contractile FPCMs. Not only this, but FPCMs are capable of applying a contractile force upon those mesh products-eliciting different levels of contraction between mesh products. Such findings demonstrate this technique as a useful proof of concept for future development of in vitro hernia mesh testing.

Abdominal wall hernia repair: from prosthetic meshes to smart materials

Hernia reconstruction is one of the most frequently practiced surgical procedures worldwide. Plastic surgery plays a pivotal role in reestablishing desired abdominal wall structure and function without the drawbacks traditionally associated with general surgery as excessive tension, postoperative pain, poor repair outcomes, and frequent recurrence. Surgical meshes have been the preferential choice for abdominal wall hernia repair to achieve the physical integrity and equivalent components of musculofascial layers. Despite the relevant progress in recent years, there are still unsolved challenges in surgical mesh design and complication settlement. This review provides a systemic summary of the hernia surgical mesh development deeply related to abdominal wall hernia pathology and classification. Commercial meshes, the first-generation prosthetic materials, and the most commonly used repair materials in the clinic are described in detail, addressing constrain side effects and rational strategies to establish characteristics of ideal hernia repair meshes. The engineered prosthetics are defined as a transit to the biomimetic smart hernia repair scaffolds with specific advantages and disadvantages, including hydrogel scaffolds, electrospinning membranes, and three-dimensional patches. Lastly, this review critically outlines the future research direction for successful hernia repair solutions by combing state-of-the-art techniques and materials.

Prospective cohort study on mesh shrinkage measured with MRI after robot-assisted minimal invasive retrorectus ventral hernia repair using an iron-oxide-loaded polyvinylidene fluoride mesh

BACKGROUND

Mesh-reinforced ventral hernia repair is considered the gold standard treatment for all but the smallest of hernias. Human data on mesh shrinkage in the retrorectus mesh position is lacking. A prospective observational cohort study was performed to measure mesh shrinkage in robot-assisted minimal invasive retrorectus repair of ventral hernias.

METHODS

A cohort of 20 patients underwent a robot-assisted minimal invasive retrorectus repair of their ventral hernia. Magnetic resonance imaging (MRI) imaging was performed one month and thirteen months after implantation of an iron-oxide-impregnated polyvinylidene fluoride (PVDF) mesh to assess the decrease in mesh surface area. Inter-rater reliability among three radiologists regarding measurement of the mesh dimensions was analyzed. Quality of Life scoring was evaluated.

RESULTS

The inter-rater reliability between the radiologists reported as the intra-class correlations proved to be excellent for mesh width (ICC 0.95), length (ICC 0.98) and surface area (ICC 0.99). Between MRI measurements at one month and thirteen months postoperatively, there was a significant increase in mesh surface area (+ 12.0 cm², p = 0.0013) and mesh width (+ 0.8 cm, p < 0.001), while the length of the mesh remained unchanged (-0.1 cm, p = 0.754). Quality of Life Scoring showed a significant improvement in Quality of Life after one month and a further improvement at thirteen months (p < 0.001).

CONCLUSION

There was an excellent inter-rater reliability between three radiologists when measuring width, length, and surface area of an iron-oxide-impregnated PVDF mesh using MRI visualization. Mesh shrinkage was not observed, instead the effective mesh surface area and width of the mesh increased.

Mesh erosion into the rectum after laparoscopic posterior rectopexy: A case report

Introduction

Rectal prolapse typically presents in elderly women with protruding full-thickness rectum from the anus. Rectopexy using mesh is known to be a highly curative treatment for rectal prolapse, however, this procedure carries the risk of severe complication as mesh erosion.

Presentation of case

A 78-year-old woman who had undergone laparoscopic posterior rectopexy 4 years earlier visited the outpatient clinic with a complaint of bloody stool. A colonoscopy and computed tomography revealed that part of the mesh had migrated into the rectal lumen at 8 cm from the anal verge. Based on the above findings, a diagnosis of mesh erosion into the rectum was made. Complete removal of the mesh and tacker with rectal resection was performed. Before rectopexy, the patient had severe fecal incontinence, and her anal sphincter function was decreased, therefore, Permanent colostomy was indicated instead of anastomosis. In the resected specimen, the mesh was folded and placed in the mesenteric fat of the posterior wall of the rectum, with the corner of the edge of the mesh protruding into the inside lumen.

Discussion

Mesh erosion typically occurs when using mesh made of synthetic mesh and non-absorbable threads; it might induce chronic irritation and friction due to mesh shrinkage.

Conclusion

To prevent mesh erosion, it is important to pay attention to the mesh materials used and ensure secure fixation.

•

Mesh erosion into rectum after Laparoscopic posterior rectopexy was reported.

•

Complete removal of the mesh and tacker with rectal resection was needed.

•

Colostomy was made because of existence of severe fecal incontinence, preoperatively.

•

Paying attention to the Shrinkage and secure fixation of synthetic mesh.

The Myopectineal Orifice: A Study of Thai Cadavers

Objective

This study aimed to determine the myopectineal orifice size measured in Thai human cadavers.

Materials and Methods

A total of 30 human cadavers, comprising 55 groins, were assessed. Myopectineal orifices (MPOs) were measured in two dimensions: height from the lower border of the conjoined tendon to the upper border of the pectineal ligament and width from the lateral border of pubic tubercle to the medial border of the iliopsoas muscle.

Results

The mean MPO size is 7.13 + 0.14 cm in width and 6.66 + 0.32 m in height. The mean width and height in male cadavers are 7.16 + 0.14 and 6.84 + 0.27 cm, respectively. The mean width and height in female cadavers are 7.09 + 0.12 and 6.45 + 0.24 cm, respectively. The mean MPO area is 37.26 ± 0.027 cm², compared with the area of mesh graft 10 cm × 15 cm, 150 cm². Although the shrinkage of cadaveric tissue and mesh size were adjusted, which were 39.56 ± 0.029 and 81 cm², respectively, they were found to be sufficient for the mean MPO area. It was found that the mesh size was sufficient for the mean MPO area.

Conclusion

A mesh size of 10 cm × 15 cm is found to be the appropriate size to cover the MPO among Thais.

Safety and efficacy of absorbable and non-absorbable fixation systems for intraperitoneal mesh fixation: an experimental study in swine

PURPOSE

Choice of the best possible fixation system in terms of safety and effectiveness for intraperitoneal mesh placement in hernia surgery remains controversial. The aim of the present study was to compare the performance of four fixation systems in a swine model of intraperitoneal mesh fixation.

METHODS

Fourteen Landrace swine were utilized in the study. The experiment included two stages. Initially, four pieces of mesh (Ventralight ™ ST) sizing 10 × 5 cm were placed and fixed intraperitoneally to reinforce 4 small full thickness abdominal wall defects created with diathermy. These defects were repaired primarily with absorbable suture before mesh implantation. Each mesh was anchored with a different tack device between Absorbatack™, Protack™, Capsure™, or Optifix™. The second stage took place after 60 days and included euthanasia, laparoscopy, and laparotomy via U-shaped incision to obtain the measurements for the outcome parameters. The primary endpoint of the study was to compare the peel strength of the compound tack/mesh from the abdominal wall. Secondary parameters were the extent and quality of visceral adhesions to the mesh, the degree of mesh shrinkage and the histological response around the tacks.

RESULTS

Thirteen out of 14 animals survived the experiment and 10 were included in the final analysis. Capsure™ tacks had higher peel strength when compared to Absorbatack™ (p = 0.028); Protack™ (p = 0.043); and Optifix™ (p = 0.009). No significant differences were noted regarding the extent of visceral adhesions (Friedman's test p value 0.854), the adhesion quality (Friedman's test p value 0.506), or the mesh shrinkage (Friedman's test p value = 0.827). Four out of the ten animals developed no adhesions at all 2 months after implantation.

CONCLUSION

Capsure™ fixation system provided higher peel strength that the other tested devices in our swine model of intraperitoneal mesh fixation. Our findings generate the hypothesis that this type of fixation may be superior in a clinical setting. Clinical trials with long-term follow-up are required to assess the safety and efficacy of mesh fixation systems in hernia surgery.

Association of Mesh and Fixation Options with Reoperation Risk after Laparoscopic Groin Hernia Surgery: A Swedish Hernia Registry Study of 25,190 Totally Extraperitoneal and Transabdominal Preperitoneal Repairs

BACKGROUND

International guidelines concerning mesh and mesh fixation options in laparoscopic totally extraperitoneal (TEP) and transabdominal preperitoneal (TAPP) groin hernia repair are based on studies focusing on either mesh or fixation. We hypothesized that the value of such recommendations is limited by lacking knowledge on how mesh and fixation interact. The current registry-based nationwide cohort study compared different mesh/fixation combinations for relative risks for reoperation after TEP and TAPP groin hernia repair.

STUDY DESIGN

All TEP and TAPP registered in the Swedish Hernia Registry 2005 to 2017 with standard polypropylene (StdPPM) or lightweight (LWM) flat mesh, having tack, fibrin glue, or no fixation, were included. The endpoint was reoperation due to recurrence as of December 31, 2018. Multivariable Cox regression rendered relative risk differences between the exposures, expressed as hazard ratios (HR) with 95% CIs.

RESULTS

Of 25,190 repairs, 924 (3.7%) were later reoperated for recurrence. The lowest, mutually equivalent, reoperation risks were associated with StdPPM without fixation (HR 1), StdPPM with metal tacks (HR 0.8, CI 0.4 to 1.4), StdPPM with fibrin glue (HR 1.1, CI 0.7 to 1.6), and LWM with fibrin glue (HR 1.2, CI 0.97 to 1.6). Except for with fibrin glue, LWM correlated with increased risk, whether affixed with metal (HR 1.7, CI 1.1 to 2.7), or absorbable tacks (HR 2.4, CI 1.8 to 3.1), or deployed without fixation (HR 2.0, CI 1.6 to 2.6).

CONCLUSIONS

With StdPPM, neither mechanical nor glue fixation seemed to improve outcomes. Thus, for this mesh category, we recommend nonfixation. With LWM, we recommend fibrin glue fixation, which was the only LWM alternative on par with nonaffixed StdPPM.

Prospective ultrasonographic follow-up of transvaginal lightweight meshes: a 1-year multicenter study

INTRODUCTION AND HYPOTHESIS

The use of new lightweight meshes in pelvic organ prolapse (POP) surgery may reduce complications related to mesh retraction (chronic pain, dyspareunia, and mesh exposure). The aim of this study was to investigate changes in the area and position of Uphold Lite™ mesh 6 weeks and 12 months after anterior and/or apical prolapse repair.

METHODS

This observational prospective multicenter study included patients who had undergone transvaginal surgery for symptomatic POP-Q stage ≥ II anterior and/or apical compartment prolapse with placement of Uphold Lite mesh. The dimensions and position of the mesh were evaluated at 6 weeks and 12 months by ultrasonography. Correlations between ultrasonographic mesh characteristics and POP recurrence were analyzed.

RESULTS

Fifty evaluable women with an average age of 66.8 years were included. No statistically significant difference in mesh area was found between week 6 and month 12 postoperatively, either at rest (1746.92 vs. 1574.48 mm²; p = 0.15) or on Valsalva (1568.81 vs. 1542.98 mm²; p = 0.65). The ROC-AUC of the distance between the mesh and the bladder neck (M-BN) at 6 weeks for predicting cystocele recurrence at 12 months was 0.764 (95% CI 0.573-0.955) at rest and 0.724 (95% CI 0.533-0.916) on Valsalva. An M-BN distance > 12.5 mm could predict cystocele recurrence at month 12 with a sensitivity of 80% and a specificity of 69%.

CONCLUSIONS

Ultrasonographic measurements of the Uphold Lite™ mesh appear to remain stable between 6 weeks and 12 months postoperatively. M-BN distance correlates with cystocele recurrence. These results appear to confirm the value of ultrasound in mesh evaluation.

[Titanium mesh implants in herniology]

Literature review is devoted to the main implants used in hernia surgery and their disadvantages. Advisability of titanium mesh implants in surgery of anterior abdominal wall hernias is shown.

An easier Lichtenstein hernioplasty

BACKGROUND

The Lichtenstein technique is used worldwide because of its rapid learning curve, good results and low recurrence rates. In this approach, a lateral tie-shaped incision is made on the mesh, involving the spermatic funiculus and thus correcting the deep inguinal ring defect by narrowing it. The lateral tie, however, does not prevent the wrinkling of the upper portion of the mesh that is caused by the arched shape of the inguinal ligament, where the lower edge of the prosthesis is sutured.

OBJECTIVE

To describe a variation of the Lichtenstein technique that is easy to perform, maintains the advantages and prevents wrinkling of the mesh and allows for better mesh accommodation in the inguinal region.

METHODS

The main feature of this approach is to cut the mesh vertically and to make the tie over the spermatic cord by overlapping the two resulting portions without wrinkling them. The final appearance is clearly more anatomical, allowing the mesh to be perfectly adapted for each patient.

RESULTS

We operated on consecutive patients using this approach for more than 5 years. There have been no recurrences or specific mesh complications during follow-up, and the surgical aspect of this technique was clearly more anatomical.

CONCLUSIONS

This method appears to be easier to perform and the surgical aspects of the technique are more anatomical for the patient.

Intraluminal mesh migration causing enteroenteric and enterocutaneous fistula: a case and discussion of the 'mesh problem'

The use of synthetic mesh in the abdominal compartment has recently become a topic of debate as high profile public cases have called into question their safety. Several case reports have demonstrated significant complications due to intra-abdominal mesh. Furthermore, some studies have suggested that the rates of these severe complications are underestimated. We present the case of a patient who developed an enteroenteric and enterocutaenous fistulae, an abdominal wall collection and an intraperitoneal inflammatory mass from intraluminal migration of a synthetic mesh inserted during laparoscopic incisional hernia repair. We discuss the considerations and complications of using synthetic mesh for ventral hernia repair and discuss the scientific evidence behind the increasingly apparent 'mesh problem'.

Prospective cohort study on mesh shrinkage measured with MRI after laparoscopic ventral hernia repair with an intraperitoneal iron oxide-loaded PVDF mesh

BACKGROUND

Current data on shrinkage of intraperitoneal meshes come mainly from animal studies. High-quality human data in prospective studies are scarce.

METHODS

We used the ability to visualize intraperitoneal PVDF meshes enhanced with iron particles (DynaMesh IPOM visible) with magnetic resonance imaging (MRI) to determine the amount of shrinkage between 1 and 13 months postoperatively. All measurements of the width, length, and surface area of the mesh were performed with a standardized methodology independently by four radiologists blinded for the timing of the MRI.

RESULTS

Of the 15 patients undergoing laparoscopic ventral hernia repair, 13 patients received an MRI both at 1 and at 13 months. Evaluation of inter-rater reliability between the radiologists showed intra-class correlations of 0.95 (95% CI 0.92-0.98) for the width, 0.96 (95% CI 0.93-0.98) for the length, and 0.99 (90% CI 0.99-1.00) for the surface area of the mesh. The change between measurement at implantation and 1-month MRI was - 0.7 cm (P = 0.023; - 3.6%) for the width and - 1.9 cm (P = 0.001; - 7.2%) for the length. The change between 1 and 13 months was - 0.06 cm (P = 0.74; shrinkage = 0.3%) for the width, - 0.12 cm (P = 0.56; shrinkage = 0.5%) for the length, and - 4.0 cm² (P = 0.20; shrinkage = 1.0%) for the surface area of the mesh.

CONCLUSION

There is excellent inter-rater reliability between radiologists when measuring width, length, and surface area of visible intraperitoneal PVDF mesh with MRI. There is no significant shrinkage between 1 and 13 months of intraperitoneal PVDF mesh after laparoscopic ventral hernia repair.