Understanding the anatomy of the Denonvilliers fascia: review article / Compreendendo a anatomia da fáscia de Denonvilliers: artigo de revisão

Abstract The postoperative outcome of rectal cancer has been improved after the introduction of the principles of total mesorectal excision (TME). Total mesorectal excision includes resection of the diseased rectum and mesorectum with non-violated mesorectal fascia (en bloc resection). Dissection along themesorectal fascia through the principle of the "holy plane" minimizes injury of the autonomic nerves and increases the chance of preserving them. It is important to stick to the TME principle to avoid perforating the tumor; violating the mesorectal fascia, thus resulting in positive circumferential resection margin (CRM); or causing injury to the autonomic nerves, especially if the tumor is located anteriorly. Therefore, identifying the anterior plane of dissection during TME is important because it is related with the autonomic nerves (Denonvilliers fascia). Although there are many articles about the Denonvilliers fascia (DVF) or the anterior dissection plane, unfortunately, there is no consensus on its embryological origin, histology, and gross anatomy. In the present review article, I aim to delineate and describe the anatomy of the DVF inmore details based on a review of the literature, in order to provide insight for colorectal surgeons to better understand this anatomical feature and to provide the best care to their patients.

Resumo O resultado pós-operatório do câncer retal foi melhorado após a introdução dos princípios da excisão total do mesorreto (TME, na sigla em inglês). A excisão total do mesorreto inclui a ressecção do reto e do mesorreto afetados com fáscia mesorretal não violada (ressecção em bloco). A dissecção ao longo da fáscia mesorretal pelo princípio do "plano sagrado" minimiza a lesão dos nervos autônomos e aumenta a chance de preservá-los. É importante seguir o princípio da TME para evitar: a perfuração do tumor; a violação da fáscia mesorretal, resultando em margem de ressecção circunferencial (CRM) positiva; ou a lesão aos nervos autônomos, especialmente se o tumor estiver localizado anteriormente. Portanto, a identificação do plano anterior de dissecção durante a TME é importante, pois está relacionada comos nervos autonômicos (fáscia de Denonvilliers). Embora existammuitos artigos sobre a fáscia de Denonvilliers (DVF, na sigla em inglês) ou o plano de dissecção anterior, infelizmente não há consenso sobre sua origem embriológica, histologia e anatomia macroscópica. No presente artigo de revisão, retendo delinear e descrever a anatomia da DVF em mais detalhes com base em uma revisão da literatura, a fim de fornecer subsídios para os cirurgiões colorretais entenderemmelhor esta característica anatômica e fornecer o melhor cuidado para seus pacientes.

Chinese consensus on Denonvilliers' fascia preserving total mesorectal excision (iTME) (2021 version) / 中华胃肠外科杂志

In 1982, total mesorectal excision(TME) was proposed by Professor R. J. Heald, which was a milestone-style for rectal cancer surgery. The concept of TME has reduced the local recurrence rate of mid-low rectal cancer (MLRC) significantly, thus becomes the gold standard for MLRC surgery. However, the incidence of urogenital dysfunction after TME remains high, among which urinary dysfunction reaches 30%-60%, and sexual dysfunction reaches 50%-70%. In recent years, studies have shown that the removal of Denonvilliers' fascia (DVF) during TME is an important cause of postoperative urination and sexual dysfunction. Therefore, DVF preserving total mesorectal excision (iTME) has been recognized by more and more surgical experts. On the basis of existing literature and clinical practice, we organize experts to discuss and vote, put forward recommendations for several issues of iTME, and finally formulate this expert consensus. The formulation of this consensus aims to increase surgeons' awareness of the value and functional protection of DVF during TME surgery, clarify the indications and contraindications of iTME, and standardize the procedure of iTME, so as to reduce postoperative urination and sexual dysfunction and improve the quality of life of patients with MLRC. The level of evidence and recommendation of this consensus is determined by Grading Recommendations, Assessment, Development and Evaluation (GRADE), and the consensus content is determined through expert voting and Delphi method.

Value of high resolution magnetic resonance imaging for preoperative evaluation of Denonvilliers fascia in patients with rectal cancer / 中华胃肠外科杂志

Objective: Total mesorectal excision (TME) is the gold standard for surgical treatment of mid-low rectal cancer, but the postoperative incidence of urination and sexual dysfunction is relatively high. Preserving the Denonvilliers fascia (DF) during TME can reduce the postoperative incidence of urination and sexual dysfunction. In this study, high resolution magnetic resonance imaging (MRI) was used to observe the imaging performance and display of DF, so as to determine the value of this technique in preoperative evaluation of the preservation of DF. Methods: A descriptive cohort study was carried out. Clinical data of patients with rectal cancer who underwent TME and received preoperative high-resolution MRI at department of Gastrointestinal Surgery, the Third Affiliated Hospital of Sun Yat-sen University from August 2015 to June 2017 were retrospectively analyzed. The characteristics of DF were examined, and the shortest distance (d) between the anterior edge of tumor and DF was measured on high-resolution MRI. The distance d was compared between patients with stage T1-T2 and those with stage T3. Receiver operating characteristic (ROC) analysis was used to determine the predictive value of d for stage T1-T2 disease. Results: Thirty-two patients were enrolled in the study, including 27 males and 5 females with mean age of (62.9±8.9) years. DF was visualized in 96.9% (31/32) of cases on the T2WI sequence. The mean distance d in patients with stage T1-T2 disease (n=23) was (6.73±2.65) mm, and in those with stage T3 disease (n=9) was (1.30±1.15) mm (t=5.893, P<0.001). A cutoff of d >3 mm yielded specificity and positive predictive value for diagnosing stage T1-T2 disease of both 100%, sensitivity of 95.7% and negative predictive value of 90%. The optimum threshold of d was >3.05 mm, and Youden index was 0.957. Conclusions: High-resolution MRI can show the DF and accurately evaluate the relationship of DF with tumor in rectal cancer patients. Analysis on d value can provide an objective basis for the safe preservation of DF.

Robotic versus laparoscopic total mesorectal excision with partial preservation of Denonvilliers fascia: a comparative study of short-term efficacy and urinary and erectile function / 中华胃肠外科杂志

Objective: Postoperative sexual and urinary dysfunctions are common in rectal cancer patients. This study was conducted to compare the short-term efficacy and the impact of surgery on urinary and erectile functions between laparoscopy and robotic-assisted total mesorectal excision (TME) with partial preservation of Denonvilliers fascia. Methods: A retrospective cohort study was carried out. Clinical data of 276 patients with low rectal cancer who underwent TME with partial preservation of Denonvilliers fascia in our department between January 2016 and March 2019, including 143 in robotic group and 133 in laparoscopic group, were analyzed. All the patients were positioned by rigid rectoscope, and the distance between the tumor and the anal verge was ≤7 cm. The urinary and erectile functions were followed up at postoperative 12-month and evaluated by IPSS score (0-7 points as mild symptoms, 8-19 points as moderate symptoms, 20-35 points as severe symptoms; the excellent rate was defined as the rate of mild symptoms) and IIEF-5 score (score ≥ 22 as no dysfunction, 12-21 as mild, 8-11 as moderate, and 5-7 as severe) respectively. Results: There were no significant differences in operation ways between the two groups (P>0.05). The operation time of the robotic group was longer than that of the laparoscopic group [(312.5±75.4) minutes vs. (273.9±65.6) minutes, t=4.514, P<0.001]. However, in patients with higher body mass index (BMI ≥25 kg/m(2)), there was no significant difference in operation time between the two groups [(309.3±78.5) minutes vs. (276.1±75.3) minutes, t=1.751, P=0.085]. The time to postoperative flatus [(1.3±0.4) days vs. (1.5±1.0) days, t=-2.037, P=0.046], defecation [1 (1-5) days vs. 1 (1-12) days, Z=-2.209, P=0.008] and liquid diet [(1.0±0.1) days vs. (1.2±0.1) days, t=3.195, P=0.002] in the robotic group were all shorter than those in the laparoscopic group. While postoperative length of hospital stay in the robotic group was longer than that in the laparoscopic group [(8.5±5.5) days vs. (7.2±3.3) days, t=2.419, P=0.016]. There were no significant differences between the two groups in intraoperative blood loss, conversion rate, morbidity of postoperative complications, positive rate of distal resection margin, positive rate of circumferential resection margin, and the number of resected lymph nodes (all P>0.05). At postoperative 12 months, none of the robotic group nor the laparoscopic group had severe urinary dysfunction, and the overall excellent rate of urinary function reached 97.6% (83/85) and 98.4% (61/62) respectively. The rate of normal and mild erectile dysfunction in the robotic group and the laparoscopic group were 92.2% (47/51) and 92.6% (38/41) respectively (P>0.05). There was no significant difference between the two groups was found regarding the urinary and erectile function (both P>0.05). Conclusions: Compared with laparoscopic, the robotic TME with partial preservation of Denonvilliers fascia has no significant differences in surgical safety and short-term efficacy. They have similar advantages in the protection of urinary and erectile function. Meanwhile the robotic surgery presents faster postoperative recovery of gastrointestinal function.

Anatomy research on Denonvilliers fascia and its significance in nerve-preservation rectal cancer surgery / 中华胃肠外科杂志

Urinary and sexual dysfunctions due to intraoperative pelvic autonomic nerve injury have become the most common complications of rectal cancer surgery, seriously affecting postoperative quality of life. How to protect the nerve and urogenital function while ensuring radical resection for rectal cancer has become the focus of research. We previously carried out a series of systematic studies on Denonvilliers fascia, an important anatomical structure closely related to protection of pelvic autonomic nerve, and demonstrated the importance of Denonvilliers fascia in preservation of intraoperative pelvic autonomic nerve and protection of postoperative urogenital function from aspects of anatomy, physiology, tissue, operation practice and so on. Meanwhile, based on the interim results of our multicenter randomized controlled study, we confirmed that total mesorectal excision with preservation of Denonvilliers fascia (innovative TME, iTME) could effectively reduce the incidence of postoperative urinary and sexual dysfunctions in male patients with mid-low rectal cancer, without sacrificing oncologic outcome. In this article, combined with our research results, we review the literature on anatomy research progress of Denonvilliers fascia to demonstrate the significance and research prospect of Denonvilliers fascia in the pelvic autonomic nerve preservation surgery for rectal cancer.

Technique of dissection in the pre-rectal space of laparoscopic total mesorectal excision / 中华消化外科杂志

The development of laparoscopic total mesorectal excision (TME) has been promoting the better understanding of the anatomy in pre-rectal space for surgeons.If the dissection in pre-rectal space was inappropriate and entered into wrong anatomic planes,it would be easier to cause the proper fascia of rectum incomplete and damage the neurovascular bundies,and reduce the radical surgery outcome and induce urinary and sexual dysfunction,finally,affect the prognosis in patients.For surgical approach in pre-rectal space,the author proposed:Based on the related literatures,transecting the Denonvilliers' fascia (DVF) when it's definitely thickened after cutting the peritoneum 0.5 cm anterior to peri-toneal reflection,entering and dissecting in the space between DVF and the proper fascia of rectum,and forming a typical Three-line feature,including the cutting line of peritoneal reflection,the proximal and distal cutting lines of DVF,which can serve as the mark line and mark plane of the entrance to pre-rectal space.Not only this approach can keep the proper completeness of rectal fascia,but also it maximally reserves the DVF.Here,this article discussed the embryonic origins and anatomic characters of DVF,the structures of neurovascular bundles,dissection in the pre-rectal space,surgical approach and clinical outcomes between DVF and laparoscopic TME.

Nerves and fasciae in and around the paracolpium or paravaginal tissue: an immunohistochemical study using elderly donated cadavers / 대한해부학회지

The paracolpium or paravaginal tissue is surrounded by the vaginal wall, the pubocervical fascia and the rectovaginal septum (Denonvilliers' fascia). To clarify the configuration of nerves and fasciae in and around the paracolpium, we examined histological sections of 10 elderly cadavers. The paracolpium contained the distal part of the pelvic autonomic nerve plexus and its branches: the cavernous nerve, the nerves to the urethra and the nerves to the internal anal sphincter (NIAS). The NIAS ran postero-inferiorly along the superior fascia of the levator ani muscle to reach the longitudinal muscle layer of the rectum. In two nulliparous and one multiparous women, the pubocervical fascia and the rectovaginal septum were distinct and connected with the superior fascia of the levator at the tendinous arch of the pelvic fasciae. In these three cadavers, the pelvic plexus and its distal branches were distributed almost evenly in the paracolpium and sandwiched by the pubocervical and Denonvilliers' fasciae. By contrast, in five multiparous women, these nerves were divided into the anterosuperior group (bladder detrusor nerves) and the postero-inferior group (NIAS, cavernous and urethral nerves) by the well-developed venous plexus in combination with the fragmented or unclear fasciae. Although the small number of specimens was a major limitation of this study, we hypothesized that, in combination with destruction of the basic fascial architecture due to vaginal delivery and aging, the pelvic plexus is likely to change from a sheet-like configuration to several bundles.

Anatomic characteristics of the Denonvilliers fascias and its application in rectal surgery / 中华消化外科杂志

Denonvilliers fascia locating between the front of the rectum and urogenital organs is an important barrier separating the urogenital organs and the rectum.It has great significance in the clinical treatment of rectal tumors and genitourinary system tumors.However,controversial on the embryological origins and anatomic characteristics of the Denonvilliers fascias still exist.In this article,the embryonic origin,anatomical structure,adjacent structures and clinical applications of the Denonvilliers fascias were introduced.

Anatomic Basis of Sharp Pelvic Dissection for Total Mesorectal Excision with Pelvic Autonomic Nerve Preservation for Rectal Cancer

Optimal goals of rectal cancer surgical treatment should include appropriate local control, higher survival rates, scrupulous operation procedures and good quality of life with maintained sexual and voiding function through the conservation of anal sphincter. Complete surgical removal of rectal cancer mass and adjacent lymph nodes in en-bloc package decreases the risk of local recurrence. Furthermore heightened awareness of better surgical techniques has created much interest in the anatomy involved in total mesorectal excision (TME), with particular focus on the fascial planes, nerve plexuses and their relationship to the surgical planes of excision. Total mesorectal excision focuses on several technical components and the quality of operated specimen. Sharp anatomic pelvic dissection along the visceral pelvic fascia must avoid any breach from the mesorectum haboring metastatic tumor deposits and lymph nodes. Also any coning down or blunt dissection should not be allowed. The rectal cancer mass and its surrounding mesorectum must be removed as one complete unit. Circumferential and distal resection margin must be also adequately obtained. Such sharp pelvic dissection instead of blunt dissection requires precised knowledge of the pelvic anatomy. Studying the hemisected cadevaric pelvis shows a clear relationship between the fascia and rectum. Also pelvic autonomic nerves can be saved to preserve the patient's sexual and voiding functions. Therefore the clincial importances of anatomical structures must be emphasized at each step of surgery. Upon such understanding of techniques, TME was performed in rectal cancer patients routinely and was able to obtain fair oncologic results and improved quality of life regarding sexual and voiding functions.