Update in Transvaginal Grafts: The Role of Lightweight Meshes, Biologics, and Hybrid Grafts in Pelvic Organ Prolapse Surgery

Transvaginal mesh/grafts have been popularized over the past 20 years in an attempt to improve the longevity of traditional vaginal pelvic organ prolapse (POP) surgery. Several national bodies have concluded that the proposed benefits of mesh/graft implantation are outweighed by the significant increase in surgery complications related to these products. As a consequence mesh products for vaginal POP surgery have been withdrawn from use in many countries. This article is a narrative review of newer mesh and graft products including lightweight polypropylene mesh products, biological grafts, hybrid grafts, and tissue engineered grafts.

Assessing pelvic organ prolapse recurrence after minimally invasive sacrocolpopexy: does mesh weight matter?

INTRODUCTION AND HYPOTHESIS

There has been a trend toward the use of ultra-lightweight mesh types for minimally invasive sacrocolpopexy. We hypothesized that ultra-lightweight mesh would have a greater proportion of composite anatomical pelvic organ prolapse recurrence than lightweight mesh.

METHODS

Retrospective cohort study of minimally invasive sacrocolpopexies at two academic institutions from 2009 to 2016. Our primary outcome was composite anatomical prolapse recurrence, defined as prolapse beyond the hymen or retreatment with pessary or surgery, compared between ultra-lightweight (≤21 g/m² [range 19-21]) and lightweight (>21 g/m² [range 35-50]) mesh types. We assessed time to prolapse recurrence using Kaplan-Meier and Cox regression.

RESULTS

The cohort consisted of 1,272 laparoscopic (n = 530, 41.7%) and robotic-assisted sacrocolpopexies (n = 742, 58.4%). Lightweight mesh was used in 745 procedures (58.6%) and ultra-lightweight mesh in 527 (41.4%). The lightweight mesh had longer median follow-up than the ultra-lightweight group (344 [IQR 50-670] vs 143 days [IQR 44-379], p < 0.01). There was no difference in composite anatomical prolapse recurrence between lightweight and ultra-lightweight mesh (54 [7.2%] vs 35 [6.6%], p = 0.68). Ultra-lightweight mesh demonstrated a shorter time to prolapse recurrence (p < 0.01), which remained significant on multivariate Cox regression (HR 2.38 [95% CI 1.47-3.87]). The lightweight mesh had significantly more mesh complications (43 [5.8%] vs 7 [1.3%], p < 0.01).

CONCLUSIONS

Ultra-lightweight mesh for minimally invasive sacrocolpopexy was not associated with a higher proportion of composite anatomical prolapse recurrence; however, it was associated with a shorter time to recurrence. Longer follow-up is needed to assess the clinical importance of this finding, particularly given the trade-off of more complications with lightweight mesh.

Mechanical properties of warp-knitted hernia repair mesh with various boundary conditions

In this paper, two most representative hernia repair meshes were prepared with 0.15 mm polypropylene monofilaments via warp knitting technology, and their mechanical properties were tested in various aspects. Meanwhile, a focused investigation of the boundary conditions between the sutures and the mesh was simulated in several directions innovatively. The results revealed that the hernia repair mesh with different structures has different mechanical properties, and the mechanical properties of standard hernia repair mesh were superior to that of lightweight hernia repair mesh. In order to reduce foreign body sensation and postoperative adverse reactions significantly, the lightweight hernia repair mesh may be preferred. At the same time, the mesh should be placed in the proper direction to comply with the anisotropy of abdominal wall during operation. The area where the hernia mesh is in contact with the sutures was vulnerable to damage. The curved or wrinkled area of the hernia repair mesh increases with the increase of load, which may lead to poor tissue growth, a strong inflammatory response, and even the recurrence of the hernia. Therefore, the hernia repair meshes with different structures may require unique suture techniques. And they also should be further treated prior to implantation. This study provides a theoretical basis for development, utilization and improvement of meshes. Further research will focus on the biomechanical properties of the mesh after implantation in vivo studies.

Lower recurrence rate with heavyweight mesh compared to lightweight mesh in laparoscopic totally extra-peritoneal (TEP) repair of groin hernia: a nationwide population-based register study

Purpose

Lightweight meshes (LWM) have shown benefits compared to heavyweight meshes (HWM) in terms of less postoperative pain and stiffness in open inguinal hernia repair. It appears to have similar advantages also in TEP, but concerns exist if it may be associated with higher recurrence rates. The aim of the study was to compare reoperation rate for recurrence of LWM to HWM in laparoscopic totally extra-peritoneal (TEP) repair.

Methods

All groin hernias operated on with TEP between 1 January 2005 and 31 December 2013 at surgical units participating in The Swedish Hernia Register were eligible. Data included clinically important hernia variables. Primary endpoint was reoperation for recurrence. Median follow-up time was 6.1 years (0–11.5) with minimum 2.5 years postoperatively.

Results

In total, 13,839 repairs were included for statistical analysis and 491 were re-operated for recurrence. Multivariate analysis demonstrated significantly increased risk of reoperation for recurrence in LWM 4.0% (HR 1.56, P < 0.001) compared to HWM 3.2%. This was most evident in direct hernias (HR 1.75, P < 0.001) and in hernia repairs with a defect > 3 cm (HR 1.54, P < 0.021). The risk of recurrence with use of LWM in indirect hernias and in hernia repairs with a defect < 1.5 cm was more comparable to HWM.

Conclusions

Lightweight meshes were associated with an increased risk of reoperation for recurrence compared to HWM. While direct hernias and larger hernia defects may benefit from HWM to avoid increased recurrence rates, LWM is recommended to be used in indirect and smaller hernia defects in TEP repair.

Pain and quality of life after inguinal hernia surgery: a multicenter randomized controlled trial comparing lightweight vs heavyweight mesh (Supermesh Study)

Mesh repair has significantly reduced recurrence rate after groin hernia surgery. Recently, attention has shifted to issues such as chronic pain and discomfort, leading to development of lightweight and partially re-absorbable meshes. The aim of the study was to evaluate the effect of lightweight mesh vs heavyweight mesh on post-operative pain, discomfort and quality of life in short and medium term after inguinal hernia surgery. Eight hundred and eight patients with primary inguinal hernia were allocated to anterior repair (Lichtenstein technique) using a lightweight mesh (Ultrapro^®) or a heavyweight mesh (Prolene^®). Primary outcomes were incidence of chronic pain and discomfort at 6-month follow-up. Secondary endpoints were quality of life (QoL), pain and complication at 1 week, 1 and 6 months. At 6 months, 25% of patients reported pain of some intensity; severe pain was reported by 1% of patients in both groups. A statistically significant difference in favour of lightweight mesh was found at multivariable analysis for pain (1 week and 6 months after surgery: p = 0.02 and p = 0.04, respectively) and QoL at 1 month and 6 months (p = 0.05 and p = 0.02, respectively). There was no difference in complication rate and no hernia recurrences were detected. The use of lightweight mesh in anterior Lichtenstein inguinal hernia repair significantly reduced the incidence of pain and favourably affected the perceived quality of life at 6 months after surgery compared to heavyweight mesh.

Standard polypropylene mesh vs lightweight mesh for Lichtenstein repair of primary inguinal hernia: a randomized controlled trial

PURPOSE

The aim of the present clinical study was to compare early and late outcomes after inguinal hernia repair with the heavyweight mesh (HW) and lightweight mesh (LW) during a 3 year follow-up period.

METHODS

226 patients were randomized into LW and HW mesh groups, both of which underwent unilateral primary inguinal hernia repair via the Lichtenstein technique. Wound complications (infection, hematoma, seroma), hernia recurrence, pain and feeling of foreign body in inguinal area were determined in patients. Pain was measured by visual analogue scale.

RESULTS

No statistical difference has been found between LW and HW groups by wound complication (P = 0.80). One case of hernia recurrence has been mentioned in both groups one year after hernioplasty. But there was no detectable difference between the two groups. No significant difference has been found between LW and HW groups by frequency of chronic pain 7 days, 1 and 3 months, 1, 2, and 3 years after surgery. As for the feeling of foreign body in groin it is similar in both groups after 1 and 3 months. Level of feeling of foreign body was significantly lower in LW group 1, 2, and 3 years after surgery, than in HW group (P = 0.03, P = 0.02, P = 0.02, respectively).

CONCLUSION

Our research shows no significant difference in wound complications, hernia recurrence and chronic pain after Lichtenstein hernioplasty, by using of LW and HW meshes. The usage of the LW mesh was associated with less feeling of foreign body than that of the HW mesh, what can be considered as prevalence of LW mesh hernioplasty.