Fate of mesoangioblasts in a vaginal birth injury model: influence of the route of administration

Currently cell therapy is considered as an experimental strategy to assist the healing process following simulated vaginal birth injury in rats, boosting the functional and morphologic recovery of pelvic floor muscles and nerves. However, the optimal administration route and dose still need to be determined. Mesangioblasts theoretically have the advantage that they can differentiate in skeletal and smooth muscle. We investigated the fate of mesoangioblasts transduced with luciferase and green fluorescent protein reporter genes (rMABseGFP/fLUC) using bioluminescence, immunofluorescence and RT-PCR in rats undergoing simulated birth injury. rMABseGFP/fLUC were injected locally, intravenously and intra-arterially (common iliacs and aorta). Intra-arterial delivery resulted in the highest amount of rMABseGFP/fLUC in the pelvic organs region and in a more homogeneous distribution over all relevant pelvic organs. Sham controls showed that the presence of the injury is important for recruitment of intra-arterially injected rMABseGFP/fLUC. Injection through the aorta or bilaterally in the common iliac arteries resulted in comparable numbers of rMABseGFP/fLUC in the pelvic organs, yet aortic injection was faster and gave less complications

Short term post-operative morphing of sacrocolpopexy mesh measured by magnetic resonance imaging

Sacrocolpopexy (SC) involves suspension of the vaginal vault or cervix to the sacrum using a mesh. Following insertion, the meshes have been observed to have undergone dimensional changes.status: publishe

Transvaginal Mesh Insertion in the Ovine Model

This protocol describes mesh insertion into the rectovaginal septum in sheep using a single vaginal incision technique, with and without the trocar-guided insertion of anchoring arms. Parous sheep underwent the dissection of the rectovaginal septum, followed by the insertion of an implant with or without four anchoring arms, both designed to fit the ovine anatomy. The anchoring arms were put in place using a trocar and an "outside-in" technique. The cranial arms were passed through the obturator, gracilis, and adductor magnus muscles. The caudal arms were fixed near the sacrotuberous ligament, through the coccygeus muscles. This technique allows for the mimicking of surgical procedures performed in women suffering from pelvic organ prolapse. The anatomical spaces and elements are easily identified. The most critical part of the procedure is the insertion of the cranial trocar, which can easily penetrate the peritoneal cavity or the surrounding pelvic organs. This can be avoided by a more extensive retroperitoneal dissection and by guiding the trocar more laterally. This approach is designed only for experimental testing of novel implants in large animal models, as trocar-guided insertion is currently not used clinically.status: publishe

In vivo evidence of significant levator-ani muscle stretch on MR images of a live childbirth

Vaginal childbirth is believed to be a significant risk factor for the development of pelvic floor dysfunction later in life. Previous studies have explored the use of medical imaging and simulations of childbirth to determine the stretch in the levator ani muscle. Bamberg et al, 2012, have recorded MR images of a live childbirth of a 24 year old woman giving birth vaginally for the second time, using a 1.0 Tesla open high-field scanner. Our objective was to determine the stretch ratios in the levator muscle using these MR images of live childbirth.status: publishe

Simulated vaginal delivery causes transients vaginal smooth muscle hypersensitivity and urethral sphincter dysfunction

BACKGROUND: Although pelvic floor dysfunction (PFD) has a multifactorial etiology, pregnancy and childbirth are considered crucial events predisposing to urinary incontinence as well as pelvic organ prolapse, which are highly prevalent. Rats are the most frequently used animal model and pudendal nerve crush (PNC) and vaginal distension (VD) are often used to mimic vaginal delivery. OBJECTIVE: To document the time course of events after simulated vaginal delivery (SVD) on the urethral sphincter and the vaginal smooth muscle layer. MATERIALS AND METHODS: Virgin female Sprague-Dawley rats were subjected to SVD (PNC + VD) or sham surgery and evaluated at 7, 14, 21, and 42 days after the injury. Urethral function was determined in vivo by microultrasound during cystometry and vaginal smooth muscle layer was harvested for in vitro pharmacologic investigation by isometric tension recording. Furthermore, vaginal and urethral samples were investigated by immunohistochemistry and real-time quantitative polymerase chain reaction. RESULTS: Microultrasound showed no bursting of the urethral sphincter in the SVD group at 7 days with a functional recovery starting at 14 days, and normal bursting at 21 and 42 days. Vaginal smooth muscle showed higher sensitivity to carbachol at 14 and 21 days after injury; however, at 42 days, its sensitivity decreased when compared with sham. CONCLUSION: SVD induces urethral dysfunction and a shift in vaginal smooth muscle contractile responses to carbachol.status: publishe

Long-term outcomes of a randomized controlled trial comparing trans-obturator vaginal mesh with native tissue repair in the treatment of anterior vaginal wall prolapse

International audienceIntroduction and hypothesis: The aim of this study was to report the long-term subjective and objective outcomes after transvaginal mesh (TVM) or native tissue repair.Methods: Prospective, randomized, multicenter study conducted between April 2005 and December 2009 comparing anterior colporrhaphy with trans-obturator vaginal mesh (Pelvitex/Ugytex®, Sofradim, Trevoux, France) for the treatment of anterior vaginal wall prolapse. The primary endpoint was functional recurrence rate 5-8 years after surgery. Secondary endpoints consisted of anatomical results, mesh-related morbidity and patient satisfaction measured through validated questionnaires.Results: Of the 147 women originally included, 75 (51%) were successfully re-contacted a median of 7 years after the initial surgery. The primary outcome, subjective recurrence of prolapse, was similar between the TVM and the anterior colporrhaphy groups (31 vs 34% respectively). Anatomical recurrence was less likely in the TVM group (67 vs 24%, p = 0.004). Mesh exposure occurred in 4 of the 39 patients (13%) during follow-up, 2 of which had a surgical reintervention. Reintervention for prolapse took place in 7 patients (9%).Conclusion: Seven-year follow-up showed similar functional outcomes for mesh and native tissue repair in anterior vaginal wall prolapse. TVM did not reduce repeat surgery in the long term; it did, however, reduce anatomical recurrence. Mesh exposure rates were relatively high, but no difference in outcome of pain or dyspareunia was noted

In vivo documentation of shape and position changes of MRI-visible mesh placed in rectovaginal septum

Large deformations in synthetic meshes used in pelvic organ prolapse surgery may lead to suboptimal support for the underlying tissue, graft-related complications as well as recurrence. Our aim was to quantify in vivo longitudinal changes in mesh shape and geometry in a large animal model. We compare two commonly used mesh shapes, armed and flat, that are differently affixed. The secondary outcomes were active and passive biomechanical properties.status: publishe

Ultrasound visualization of sacrocolpopexy polyvinylidene fluoride meshes containing paramagnetic Fe particles compared with polypropylene mesh

INTRODUCTION AND HYPOTHESIS: Paramagnetic Fe particles can be added during synthetic mesh production to allow visibility on magnetic resonance imaging. Our aim was to evaluate whether transperineal ultrasound (TPUS) allows visualization, measurement, and characterization of polyvinylidene fluoride (PVDF mesh) containing Fe particles compared with regular polypropylene (PP) meshes used for sacrocolpopexy. METHODS: Women up to 1.5 years after laparoscopic sacrocolpopexy who were implanted with a PP or PVDF mesh underwent clinical examination and 2D, 3D, and 4D TPUS. Acquired volumes were analyzed offline for mesh position at rest and maximal Valsalva and for mesh dimensions and characteristics, with the operator blinded to group assignment. The two groups were compared. RESULTS: There were 17 women in the PP and 25 in the PVDF mesh group, without differences in baseline demographics. None had significant prolapse, recurrence, symptoms, or complications. On TPUS, mesh was visible in all patients both caudally (perineal) and cranially but was more echogenic in the PVDF mesh group. Mesh length from distal to proximal that was visible on TPUS was longer for PVDF mesh, for both anterior and posterior vaginal arms (all P < 0.05), and for mesh above the vaginal apex (P = 0.002). The inferior aspects of the mesh showed areas of double mesh layers, suggesting folding in 80% of women in both groups, without symptoms. CONCLUSIONS: PVDF mesh permits clearer visualization and is seen over a longer stretch on TPUS, with longer visible mesh arms. The latter can be due to differences in operative technique, presence of microparticles, implant textile structure, or patient characteristics.status: publishe

Exo-anal imaging of the anal sphincter: a comparison between introital and transperineal image acquisition

INTRODUCTION AND HYPOTHESIS: Three-dimensional exoanal ultrasound imaging of the anal sphincter may be obtained transperineally with a convex probe, or at the introitus with a transvaginal probe. We hypothesised that introital acquisition would yield better quality and more reproducible evaluation. METHODS: We acquired three 3D volumes of the anal sphincter (one transperineal transverse with a 4- to 8-MHz convex probe and two introital with a 5- to 9-MHz probe in transverse and mid-sagittal view) in 20 representative women attending the gynaecology clinic. Each 3D dataset was anonymised and hence blinded for clinical data and for acquisition method. Images were analysed off-line by two expert specifically trained ultrasonographers in a random order to assess image quality, sphincter integrity and sphincteric measurements. We assessed the intra- and interrater agreement by the Cohen's kappa (κ) and by the intraclass correlation coefficient for categorical and continuous variables respectively. RESULTS: The mid-sagittal introital acquisition had most inconclusive images owing to unsatisfactory quality, on which raters agreed (К = 0.80). Subsequently, agreement in the anal sphincter evaluation between transverse introital and transperineal acquisitions was compared. Agreement on internal anal sphincter gap was excellent for both transverse introital (К = 0.87) and transperineal acquisition (К = 0.93). Agreement on external anal sphincter discontinuity was excellent for the transperineal acquisition (К = 0.87) and good for the transverse introital acquisition (К = 0.73). Intra- and interrater agreement of external and internal anal sphincteric measurements were best for transperineal acquisitions. CONCLUSIONS: In our hands, transperineal acquisition with a 4- to 8-MHz probe performed better than introital acquisition with a 5- to 9-MHz probe in the assessment of the anal sphincter complex.status: publishe