Neurovascular quantitative study of the uterosacral ligament related to nerve-sparing radical hysterectomy

Endometriosis and the Fallopian Tubes: Theories of Origin and Clinical Implications

Endometriosis is a common, oestrogen driven chronic condition, where endometrium-like epithelial and stromal cells exist in ectopic sites. At present, no curative treatments are available and the existing evidence for disease progression is conflicting. The pathogenesis is still unknown and evidently complex, as mechanisms of initiation may depend on the anatomical distribution of endometriotic lesions. However, amongst the numerous theories and plethora of mechanisms, contributions of the fallopian tubes (FT) to endometriosis are rarely discussed. The FT are implicated in all endometriosis associated symptomatology and clinical consequences; they may contribute to the origin of endometriotic tissue, determine the sites for ectopic lesion establishment and act as conduits for the spread of proinflammatory media. Here, we examine the available evidence for the contribution of the human FT to the origin, pathogenesis and symptoms/clinical consequences of endometriosis. We also examine the broader topic linking endometriosis and the FT epithelium to the genesis of ovarian epithelial cancers. Further studies elucidating the distinct functional and phenotypical characteristics of FT mucosa may allow the development of novel treatment strategies for endometriosis that are potentially curative.

Efficacy of nerve‑sparing radical hysterectomy vs. conventional radical hysterectomy in early‑stage cervical cancer: A systematic review and meta‑analysis

The aim of the present study was to compare the oncological outcome of nerve-sparing radical hysterectomy (NSRH) and conventional radical hysterectomy (CRH) for early-stage cervical cancer using a meta-analysis. A systematic review and meta-analysis was conducted, including 4 randomized controlled trials (RCT), 8 case-control and 11 comparative cohort studies comparing the morbidity, pelvic dysfunctions and oncological outcome between the two surgical methods. A total of 23 studies were included in this meta-analysis. The studies reported data of patients affected by cervical cancer; were written in English; included ≥20 patients; and reported data of patients with a comparison of clinical outcomes between NSRH and CRH. Data were extracted and risk of bias was assessed by four independent reviewers. A total of 1,796 patients were included: 884 patients (49.2%) undergoing NSRH and 912 (50.8%) undergoing CRH. The meta-analyses were conducted using Review Manager version 5.3 software, which is designed for conducting Cochrane reviews. As regards perioperative parameters, NSRH was found to be associated with a lower intraoperative blood loss and a shorter length of hospital stay in comparison with CRH. Patients undergoing NSRH experienced lower incidence of urinary, colorectal and sexual dysfunction compared with patients undergoing CRH. However, the resected parametrial width was favorable in patients with CRH, suggesting that NSRH was inferior to CRH in terms of radicality. The 5-year disease-free and overall survival rates were similar between the two groups. In this systematic review and meta-analysis, the collected data to date demonstrated that the nerve-sparing approach guarantees minimized surgical-related pelvic dysfunction, with similar oncological outcomes as CRH. However, further RCTs should be conducted to confirm the superiority and safety of NSRH.

Identification and injury to the inferior hypogastric plexus in nerve-sparing radical hysterectomy

Waterjet dissection of the inferior hypogastric plexus (IHP) resulted in a more rapid return of normal urodynamics than blunt dissection (control group) in patients who received laparoscopic nerve-sparing radical hysterectomy (NSRH) in a randomized controlled study. However, the definite reasons for these results were unknown. This subgroup analysis compared the neural areas and impairment in the IHP uterine branches harvested during NSRH as an alternative to the IHP vesical branches between the waterjet and control groups. This study included samples from 30 eligible patients in each group of the trial NCT03020238. At least one specimen from each side of the IHP uterine branches was resected. The tissues were scanned, images were captured, and the neural component areas were calculated using the image segmentation method. Immunohistochemical staining was used to evaluate neural impairment. The control and waterjet groups had similar areas of whole tissues sent for evaluation. However, the control group had significantly fewer areas (median 272158 versus 200439 μm², p = 0.044) and a lower percentage (median 4.9% versus 3.0%, p = 0.011) of neural tissues. No significant changes in immunohistochemical staining were found between the two groups. For patients with residual urine ≤100 and >100 ml at 14 days after NSRH (42 and 18 patients, respectively), there were significantly different percentages of neural tissues in the resected samples (p < 0.001). Hence, Due to the accurate identification of IHP during NSRH, the waterjet dissection technique achieved better urodynamic results.

Neurovascular and lymphatic vessels distribution in uterine ligaments based on a 3D reconstruction of histological study: to determine the optimal plane for nerve-sparing radical hysterectomy

OBJECTIVE

To present the distribution of neurovascular and lymphatic vessels in uterine ligaments using 3D models based on the pathological staining of serial 2D sections of postoperative specimens.

METHODS

Serial transverse sections of fresh uterine ligaments from a patient with stage IB1 cervical squamous cell carcinoma were studied using the computer-assisted anatomic dissection (CAAD) technique. The sections were stained with hematoxylin and eosin, Weigert elastic fibers, D2-40 and immunostainings (sheep anti-tyrosine hydroxylase and rabbit anti-vasoactive intestinal peptide). The sections were then digitalized, registered and reconstructed three-dimensionally. Then, the 3D models were analyzed and measured.

RESULTS

The 3D models of the neurovascular and lymphatic vessels in uterine ligaments were created, depicting their precise location and distribution. The vessels were primarily located in the upper part of the ligaments model, while the pelvic autonomic nerves were primarily in the lower part; the lymphatic vessels were scattered in the uterine ligaments, without obvious regularity.

CONCLUSION

CAAD is an effective anatomical method to study the precise distribution of neurovascular and lymphatic vessels in uterine ligaments. It can present detailed anatomical information about female pelvic autonomic innervation and the spatial relationship between nerves and vessels and may provide a better understanding of nerve-sparing radical hysterectomy.

The 3D reconstructions of female pelvic autonomic nerves and their related organs based on MRI: a first step towards neuronavigation during nerve-sparing radical hysterectomy

OBJECTIVES

To present in vivo female pelvic autonomous innervation and the relationship between nerves and their related organs by three-dimensional (3D) reconstruction based on magnetic resonance imaging (MRI).

METHODS

Thirty patients with cervical cancer who underwent pelvic MRI and agreed to undergo additional magnetic resonance neurography (MRN) sequences were enrolled in the present study. MRI images from the same patient were acquired using T2-weighted fat saturation (T2W FS) and 3D-STIR-SPACE sequences. Detailed two-dimensional (2D) segmentation and 3D reconstruction of pelvic autonomic nerves (PAN) were performed on the basis of the images of the two sequences using 3D reconstruction software. The 2D segmentation and 3D reconstruction of pelvic organs were based on T2W FS images. The consistency of the 3D models of pelvic autonomous innervation constructed from the two sequences were analysed and compared, the pelvic autonomous innervation was presented, and the relationship between nerves and their related organs was characterised.

RESULTS

The 3D reconstructions of PAN were successfully obtained from 3D-STIR-SPACE and T2W FS sequences in 30 patients and showed high correspondence. T2W FS images also enabled 3D reconstructions of pelvic organs to visualise the 3D distribution of PAN and the positional relationships between nerves and their related organs.

CONCLUSION

The pelvic autonomic nerves and their related organs can be reconstructed on the basis of MRI to present personalised 3D anatomical information and offer individualised guidance during nerve-sparing radical hysterectomy (NSRH).

KEY POINTS

• Nerve-sparing radical hysterectomy is a developing trend in cervical cancer surgery • MRI allows reconstructions of pelvic autonomic nerves and their related organs • The 3D reconstructions provide detailed 3D anatomical information on nerves.

Anatomic relationships of the pelvic autonomic nervous system in female cadavers: clinical applications to pelvic surgery

BACKGROUND

The integrity of the pelvic autonomic nervous system is essential for proper bowel, bladder, and sexual function.

OBJECTIVE

The purpose of this study was to characterize the anatomic path of the pelvic autonomic system and to examine relationships to clinically useful landmarks.

STUDY DESIGN

Detailed dissections were performed in 17 female cadavers. Relationships of the superior hypogastric plexus to aortic bifurcation and midpoint of sacral promontory were examined; the length and width of plexus was documented. Path and width of right and left hypogastric nerves were recorded. The origin and course of the pelvic splanchnic nerves were documented. Individual nerve tissue that contributed to the inferior hypogastric plexus was noted. Relative position of nerves to arteries, viscera, and ligaments was documented. In a subset of specimens, biopsy specimens were obtained to confirm gross findings by histologic analysis. Descriptive statistics were used for data analyses and reporting.

RESULTS

In all specimens, the superior hypogastric plexus was embedded in a connective tissue sheet within the presacral space, just below the peritoneum. In 14 of 17 specimens (82.4%), the plexus formed a median distance of 21.3 mm (range, 9-40 mm) below aortic bifurcation; in the remaining specimens, it formed a median distance of 25.3 mm (range, 20.5-30 mm) above bifurcation. In 58.8% of specimens, the superior hypogastric plexus was positioned to the left of midline. The median length and width of the plexus was 39.5 (range, 11.5-68) mm and 9 (range, 2.5-15) mm, respectively. A right and left hypogastric nerve was identified in all specimens and formed a median distance of 23 mm (range, 5-32 mm) below the promontory. The median width of the hypogastric nerve was 3.5 mm (range, 3-4.5 mm) on the right and 3.5 mm (range, 2-6.5 mm) on the left. The median distance from midportion of uterosacral ligament to the closest nerve branch was 0.5 mm (range, 0-4.5 mm) on right and 0 mm (range, 0-27.5 mm) on left. In all specimens, the inferior hypogastric plexus was formed by contributions from the hypogastric nerves and branches from S3 and S4. In 47.1% of hemipelvises, S2 branches contributed to the plexus. The sacral sympathetic trunk contributed to the plexus in 16 of 34 hemipelvises where this structure was identified. The inferior hypogastric plexus formed 1-3 cm lateral to the rectum and upper third of the vagina. From this plexus, 1-3 discrete branches coursed deep to the ureter toward the bladder. A uterine branch that coursed superficial to the ureter followed the ascending branch of the uterine artery. An S4 branch was found directly attaching to lateral walls of the rectum in 53% of specimens. Pelvic splanchnic nerves merged into the inferior hypogastric plexus on the lower and medial surface of the coccygeus muscle. Histologic analysis confirmed neural tissue in all tissues that were sampled.

CONCLUSION

Anatomic variability and inability to visualize the small caliber fibers that comprise the inferior hypogastric plexus grossly likely underlines the reasons that some postoperative visceral and sexual dysfunction occur in spite of careful dissection and adequate surgical technique. These findings highlight the importance of a discussion with patients about the risks that are associated with interrupting autonomic fibers during the preoperative consent.

Lower urinary tract dysfunction after nerve-sparing radical hysterectomy

INTRODUCTION AND HYPOTHESIS

The aim of this review is to provide a comprehensive overview of the current role of nerve-sparing radical hysterectomy (NSRH) in reducing the incidence of postoperative lower urinary tract dysfunction (LUTD) and in improving quality of life.

METHODS

A detailed online search was performed using the following keywords: nerve sparing, radical hysterectomy, cervical cancer, and all these terms in combination with urinary dysfunction or bladder dysfunction in order to analyze the effect of NSRH on urinary functional outcomes. Articles retrieved were analyzed and assigned a level of evidence (LE) according to the criteria of the Centre for Evidence-Based Medicine in Oxford, UK.

RESULTS

Our review highlights the heterogeneity of conducting and reporting studies in the literature. Autonomic pelvic nerve injuries during the procedure are thought to be the major cause of LUTD. The amount of LUTD depends upon the extent and type of nerve injury. Anatomically based surgical techniques are developed to avoid nerve injury without compromising oncological control. All studies comparing NSRH to standard RH yielded promising results with respect to postoperative LUTD. A recent meta-analysis showed similar cancer control rates between the two techniques. However, controversies remain about the ideal surgical approach for nerve sparing and there is no consensus as to the level and landmarks of dissection to preserve the maximal amount of nerves without compromising oncological outcomes.

CONCLUSIONS

Available evidence suggests that NSRH is safe and associated with lower incidence of LUTD. However, there is no standardized technique for NSRH and controversies remain about its oncological safety. Long-term oncological data from multicenter surgical trials are needed as well as a universally accepted standard to report studies on NSRH.