Feasibility and benefits of the ewe as a model for vaginal surgery training

Introduction and hypothesis

The objective was to evaluate the ewe as an animal model for teaching and training in vaginal surgery.

Methods

Twenty-nine postgraduate surgeons attended a training course on vaginal prolapse surgery. After a review of human and sheep anatomy, the participants performed transvaginal meshes, vaginal hysterectomy, SSLF (Richter), and OAS repair in ewes and human cadavers. Participants completed questionnaires on the whole course.

Results

Questionnaires showed the significant superiority of ewes over human cadavers for all items evaluated regarding surgical dissections. Only identification of the sacrospinous ligament and the spine were judged to be similar in ewes and human cadavers. Participants noticed that ewe model is appropriate for vaginal prolapse surgery training for resident and for postgraduate surgeons. Two vaginal hysterectomies were also performed. Operating time, surgery, and anatomy were nearly identical to that of humans. The same conclusions were made while performing sacrospinous ligament fixation (Richter) and obstetric anal sphincter injury repair.

Conclusion

This series indicates that the ewe is a useful animal model for teaching vaginal surgery.

     

Bacteriological analysis of meshes removed for complications after surgical management of urinary incontinence or pelvic organ prolapse

The aim of this study is to examine the role of bacterial infection in complications following surgical management of urinary incontinence and genital prolapse using meshes. There were sixteen prostheses removed. Eight were monofilament polypropylene-knitted meshes, one was a silicone-coated polypropylene mesh, another was a collagen-coated polypropylene mesh, four were silicone-coated polyester meshes and two were polyester meshes. The most frequent cause for removal was symptomatic vaginal erosion (62%). Cultures were performed under aerobic, anaerobic and enrichment conditions. Infection was multimicrobial for 31% of meshes. When only one bacteria was found, it was Proteus mirabilis in 25% of cases. Forty-three per cent of bacterial quantifications were under 10³ colony-forming units per millilitre. Bacterial contamination was found in all meshes, quantification was often low, and therefore, its exact role is not yet clear.     

Role of fetal ultrasound and magnetic resonance imaging in the prenatal diagnosis of migration disorders

OBJECTIVES: To evaluate the contribution and limitations of fetal ultrasonography (US) and magnetic resonance imaging (MRI) for the diagnosis and management of migration disorders. METHODS: Over a 5-year period, 14 fetuses with pathological migration disorders, without an infectious context, were taken care of in our centre. All underwent US; nine underwent MRI as well. Sonographic and MRI data were compared with neuropathological data. RESULTS: The diagnosis of gyral disorders was obtained by US in 1/14 cases; other cerebral abnormalities were found suggesting neuronal disorder in the remainder. Cerebral MRI suggested gyral abnormality in eight of the nine cases. CONCLUSIONS: US performance is increasing. MRI appears to be a promising method for the diagnosis of fetal migration disorders, giving better results than US. It may be recommended in cases of abnormal cerebral US findings or familial clinical history. However, interpretation of MRI can be tricky and the resulting diagnosis occurs late within the pregnancy.     

Pituitary hormones inhibit the function and differentiation of fetal Sertoli cells

Although the role of pituitary hormones in fetal Sertoli cell proliferation is well understood, their involvement in fetal Sertoli cell differentiation is poorly documented. In this study, we evaluated rat fetal Sertoli cell function by measuring basal transferrin secretion ex vivo and transferrin and anti-Müllerian hormone (AMH) mRNA levels in vivo. The differentiation state of the Sertoli cells was estimated from the amount of transferrin secreted ex vivo after acute stimulation with FSH. Surprisingly, we found that the amount of transferrin secreted by each Sertoli cell in basal condition and after acute FSH stimulation decreased between 18.5 and 21.5 day post coitum (dpc), which corresponds to the onset of pituitary hormone secretion. All of the Sertoli cell parameters measured (basal and FSH-stimulated transferrin secretion ex vivo, transferrin and AMH mRNA levels in vivo) were higher in 21.5-dpc fetuses that had been decapitated on 16.5 dpc than in control littermates. Furthermore, immunostaining for AMH was strongly increased after decapitation. Taken together, these results suggest that pituitary hormones in the fetus and in the immature or adult rat differently regulate Sertoli cells, which suggests that fetal Sertoli cells have their own particular physiology.     

During exercise non-invasive ventilation in chronic restrictive respiratory failure

BACKGROUND: Exercise intolerance limits chronic restrictive respiratory failure (CRF) patients from participating in daily activities. The specific modalities that could improve exercise tolerance in these patients remain to be established. OBJECTIVE: To investigate exercise endurance and associated physiological responses with non-invasive ventilation (NIV) during exercise in restrictive CRF patients. METHODS: Eighteen patients (63+/-11 years, total lung capacity (TLC)=59+/-16% of predicted value) performed maximal exercise in spontaneous breathing conditions (MWLE) and during two constant workload exercise (CWLE) tests at 75% Pmax, with or without NIV in random order. "NIV Responders" were defined by an increase in CWLE duration of more than 50% when using NIV. RESULTS: For the whole group, CWLE duration when using NIV increased from 5.6+/-4.6 to 9.6+/-8.1 min. Increase in CWLE duration correlated with reduction in heart rate and oxygen desaturation, and dyspnea relief during exercise. NIV responders (n=9) showed more severe lung restriction (TLC: 2.6+/-0.7 versus 3.5+/-1.1L; forced vital capacity: 1.0+/-0.16 versus 1.46+/-0.38 L). At the end of MWLE, responders had a lower Vt (0.60+/-0.09 versus 0.89+/-0.34 L), a higher dead-space ratio (0.51+/-0.06 versus 0.38+/-0.12) and lower oxygen pulse (4.5+/-1.2 versus 7.4+/-3.9 ml/beat). CONCLUSION: In severely restrictive patients, NIV during exercise significantly improved exercise duration and tolerance and increased alveolar ventilation. TRIAL REGISTRATION: The enrollment of the patients started before July 1, 2005.     

Changes in elastin density in different locations of the vaginal wall in women with pelvic organ prolapse

Introduction and hypothesis

The purpose of this study was to analyze the histomorphometric properties of the vaginal wall in women with pelvic organ prolapse (POP).

Methods

In 15 women undergoing surgery for POP, full-thickness biopsies were collected at two different sites of location from the anterior and/or posterior vaginal wall. Properties of the precervical area (POP-Q point C/D) were compared with the most distal portion of the vaginal wall (POP-Q point Ba/Bp) using histological staining and immunohistochemistry. The densities of total collagen fibers, elastic fibers, smooth muscle cells, and blood vessels were determined by combining high-resolution virtual imaging and computer-assisted digital image analysis.

Results

The mean elastin density was significantly decreased in the lamina propria and muscularis layer of the vaginal wall from the most distal portion of the prolapsed vaginal wall compared with the precervical area. This difference was statistically significant in the lamina propria for both anterior (8.4?±?1.2 and 12.1?±?2.0, p?=?0.048) and posterior (6.8?±?0.5 and 10.1?±?1.4, p?=?0.040) locations, and in the muscularis for the anterior (5.2?±?0.4 and 8.4?±?1.2, p?=?0.009) vaginal wall. There were no statistically significant differences in the mean densities of collagen fibers, smooth muscle cells or blood vessels between the two locations.

Conclusions

In this study, we observed changes in elastin density in two different locations of the vaginal wall from women with POP. The histomorphometric properties of the vaginal wall can be variable from one place to another in the same patient. This result supports the existence of most vulnerable locations within the vaginal wall and the potential benefit of site-specific prolapse surgery.     

Vagina, abdominal skin, and aponeurosis: do they have similar biomechanical properties?

Introduction and hypothesis  

Despite minimal fundamental works, there is an increasing use of meshes in urogynecology. The concept is mainly based on experiences with abdominal wall surgery. We aimed to compare the biomechanical properties of vaginal tissue, abdominal aponeurosis, and skin.