从盆腔筋膜的外科解剖来理解直肠全系膜切除术的层次

目的探讨直肠系膜与盆腔筋膜和神经的关系，以明确直肠全系膜切除术合理的切除平面。方法对24具尸体的盆腔进行解剖。结果直肠周围的层次是连续的，可以分为2段3层，2段指耻骨联合至坐骨棘和坐骨棘至骶岬；3层分别为脏筋膜、膀胱腹下筋膜和壁筋膜。在膀胱腹下筋膜与脏筋膜之间存在盆丛及其膀胱、子宫神经分支，而在脏、壁筋膜之间存在腹下神经和盆内脏神经。结论直肠全系膜切除术的层次在直肠后方为脏、壁筋膜之间，而在直肠侧方实际上位于脏筋膜和膀胱腹下筋膜之间。侧后方的腹下神经、侧前方的盆丛及其分支是正确层次的标记。     

直肠系膜两个无血管层次的解剖特征

目的：探讨全直肠系膜切除的解剖学基础,明确全直肠系膜切除的切除平面。方法：对23具尸体的盆腔进行解剖,观察直肠系膜与周围筋膜、神经的关系。结果：在直肠的侧后方存在两个无血管层次．即直肠周围脂肪与脏筋膜之间的层次及脏层筋膜与壁层筋膜之间的层次。各层次内存在不同的组织结构,在直肠与脏筋膜间存在着直肠侧韧带．在脏、壁层筋膜间存在着腹下神经和盆内脏神经。结论：全直肠系膜切除的切除范围应包括脏层筋膜在内,解剖层次应为脏、壁层筋膜间层次;术中通过观察两个无血管层次中的结构可以判定是否进入了正确的全直肠系膜切除的切除层次。     

从妇科解剖的角度来理解直肠癌手术

目的统一肛肠外科和妇科重要的解剖学术语,进而阐明与直肠癌手术相关的妇科解剖。方法对32具尸体的盆腔进行解剖。结果外科解剖把盆腔筋膜由外向内、由背侧向腹侧依次为壁筋膜、膀胱腹下筋膜和脏筋膜。在膀胱腹下筋膜与脏筋膜之间存在盆丛及其出膀胱、子宫的神经分支,而在侧后方脏、壁筋膜之间存在腹下神经和盆内脏神经。结论妇科解剖所述膀胱子宫韧带深层、直肠子宫韧带或子宫骶骨韧带以及输尿管系膜实际上都是外科解剖中的盆脏筋膜的一部分。膀胱子宫韧带浅层是膀胱腹下筋膜。     

基于膜解剖的低位直肠癌侧方淋巴结“两间隙”清扫术安全性研究

目的 通过尸体解剖分析基于膜解剖的 “两间隙”侧方淋巴结清扫术的解剖学理论,探讨对低位直肠癌病人行“两间隙”清扫的安全性和可行性。方法 解剖观察24具来源于上海交通大学医学院解剖教研室的成人尸体标本,对与侧方淋巴结清扫术相关的筋膜和间隙进行记录和描述。回顾性分析同济大学附属杨浦医院2018年7月至2020年3月行3D腹腔镜下直肠全系膜切除+“两间隙”侧方淋巴结清扫术的14例低位直肠癌病人的临床资料。结果 所有24具尸体均可以明确解剖出直肠固有筋膜、尿生殖筋膜、膀胱腹下筋膜和闭孔筋膜（壁筋膜）,并在直肠侧方从内至外依次排列。直肠固有筋膜表现为覆盖在直肠及其周围脂肪表面的最内侧薄层筋膜。尿生殖筋膜是位于直肠侧后方的盆腔最为致密的筋膜,其中20例（83.3%）腹下神经位于尿生殖筋膜内;4例（16.7%）腹下神经位于尿生殖筋膜的深面。膀胱腹下筋膜是由脐动脉、膀胱下动脉和膀胱壁组成的“三角形”筋膜。临床实践表明,14例病人均在3D腹腔镜下完成侧方淋巴结清扫。侧方淋巴结清扫术时间为（175±27） min,术中出血量为（50±18）mL,2例病人出现并发症,淋巴漏和下肢疼痛各1例,术后住院时间（11±2） d。3例（21.4%）病人病理学检查证实为侧方淋巴结转移,其中1例为单纯性髂内淋巴结转移,平均侧方淋巴结检出数目（8.4±1.3）枚。结论 “三筋膜”（尿生殖筋膜、膀胱腹下筋膜和闭孔筋膜）构成了侧方淋巴结清扫术的两间隙（膀胱旁间隙和Latzko直肠旁间隙）。基于膜解剖的低位直肠癌侧方淋巴结“两间隙”清扫术依据膜解剖标记完成,层面容易辨识,血管、神经定位明确,初步的手术经验证实临床切实可行,不但可以提高手术的安全性,而且可以保证手术的根治性,值得进一步积累病例验证。     

Laparoscopic total mesorectal excision for low rectal cancer

Background

Laparoscopic total mesorectal excision for rectal cancer is coming out of age with recent publications highlighting its safety, feasibility, sound oncological outcomes, and improved quality of life. Nevertheless, laparoscopic proctectomy remains a challenging procedure. An embedded didactic video demonstrates a step-by-step laparoscopic total mesorectal excision with coloanal anastomosis for a low rectal cancer.

Methods

A five-trocar technique is shown. The key steps demonstrated are: high division of the inferior mesenteric artery, medial-to-lateral mobilization of the descending colon, high division of the inferior mesenteric vein, take-down of the splenic flexure, total mesorectal excision with division of the rectum at the pelvic floor, and side-to-end coloanal anastomosis. Principles of a good anastomosis and potential pitfalls are described, including protection of the ureter and pelvic autonomic nerves.

Results

A series of ten consecutive patients operated for low rectal cancer with total mesorectal excision is reported. Median (range) operative time and estimated blood loss were 274 (135?C360) minutes and 25 (10?C50)?ml. Median tumor height from the anal verge was 7 (4?C10)?cm. Reconstruction included three coloanal J-pouch and seven side-to-end anastomosis. Nine anastomoses were performed by using a double-stapled technique. One patient with an intersphincteric dissection required a handsewn anastomosis. A diverting ileostomy protected all coloanal anastomosis. Median length of stay was 3 (range, 2?C7) days. One of ten patients was readmitted for a small bowel obstruction. The embedded video demonstrates a total mesorectal excision down to the pelvic floor in a patient who had a T2 cancer 6?cm from the anal verge with prior open cholecystectomy and hysterectomy.

Conclusions

Laparoscopic total mesorectal excision is a safe and effective procedure. Patient selection and advanced laparoscopic skills are paramount. It is hoped that this didactic video will contribute to a wider and safer practice of laparoscopic total mesorectal excision for low rectal cancer.     

腹腔镜直肠癌根治术的相关解剖要点分析

目的根据直肠癌根治术全直肠系膜切除（total mesorectal excision,TME）的要求,从肿瘤根治和膀胱功能、性功能保护的角度探讨腹腔镜直肠癌根治术关键步骤的解剖学要点。方法2006年11月～2008年8月施行32例腹腔镜直肠癌根治术,从Toldt间隙的分离、肠系膜下动脉的处理、侧腹膜的解剖、骶前间隙和骶直肠筋膜的分离、直肠侧韧带的分离及直肠前方间隙的分离6个关键性步骤对TME手术的相关解剖进行观察和描述。结果Toldt间隙和骶前间隙是一个相互延续的筋膜间隙,走行于该间隙的腹下神经与直肠固有筋膜关系密切。骶直肠筋膜是盆壁筋膜和直肠固有筋膜在盆底部的融合,是TME手术盆腔分离的重要标志。在精囊腺平面以下,直肠前方和前侧方的解剖层面最为致密,适度的牵拉暴露和锐性分离有利于寻找正确解剖间隙和保护神经丛。结论紧贴直肠固有筋膜分离并保持该筋膜的完整是直肠癌根治手术中贯彻TME概念并保护膀胱功能和性功能的基本策略。     

The male rectourethralis and deep transverse perineal muscles and their relationship to adjacent structures examined with successive slices of celloidin-embedded pelvic viscera

Background

The precise relationship of the structures dorsal to the membranous urethra, including the rectourethralis muscle, the rhabdosphincter, the deep transverse perineal muscle (DTPM), the perineal body, and Denonvillier's fascia, remains controversial.

Objective

Our aim was to reexamine the detailed anatomy of the rectourethralis muscle and the deep transverse perineal muscle and their relationship with adjacent structures.

Design, setting, and participants

The pelvic viscera, including bladder, prostate, and rectum, were obtained from 20 formalin-fixed adult male cadavers.

Measurements

The pelvic viscera were embedded in celloidin and then cut into successive slices with an immersing-alcohol microtome. All slices were explored with anatomic microscopy.

Results and limitations

The longitudinal muscle of the anterior rectal wall was divided into anterior and posterior bundles at the junction of the rectum and anal canal. The intermediate fibers of the anterior bundle ended at the perineal body. The lateral fibers of the anterior bundle terminated at the posterior connective tissue of the bulbus penis. The DTPM occupied the space between the rhabdosphincter, rectum, and the bilateral levator ani muscle. Denonvillier's fascia terminated at the junction of the prostate and rhabdosphincter. Numerous slender nerves coming from the neurovascular bundle perforated the DTPM.

Conclusions

The anterior bundle of the longitudinal muscle of the rectum inserts into the bulbus penis forming the rectourethralis muscle and ends at the perineal body forming the rectoperinealis muscle. The anterior bundle and DTPM together may contribute to the rectal angle of the anterior rectal wall, and they support the posterior border of the rhabdosphincter.     

Quality of surgery for rectal carcinoma: comparison between open and laparoscopic approaches

Background

Macroscopic evaluation of a tumor specimen is an independent prognostic factor of oncologic outcome after total mesorectal excision (TME) for rectal cancer. This study aimed to assess macroscopic quality of specimens acquired after laparoscopic versus open TME in patients with low rectal cancer.

Patients and methods

Seventy-two patients with low rectal cancer underwent TME either by open (n = 39) or laparoscopic (n = 33) approach. In all specimens, the cut edge of the peritoneal reflection at the anterior mid-rectum, the Denonvillier's fascia, the visceral fascia covering the mesorectum both posteriorly and laterally, and the bowel wall below the mesorectum were macroscopically assessed.

Results

Colorectal anastomoses were located significantly lower in the laparoscopic than in the open group (P < .001). The Denonvillier's fascia was violated in 7 patients after open surgery (P = .01). A significantly more complete TME with intact visceral pelvic fascia was performed after laparoscopy compared with open surgery (P = .025).

Conclusions

Laparoscopy offers a macroscopically more complete specimen after TME for rectal cancer than the open approach because it offers a better view in the pelvis.     

直肠侧韧带的解剖与临床意义

目的 研究直肠侧韧带的临床解剖及其与直肠癌手术的关系.方法 对23具尸体的盆腔进行解剖.结果 23具尸体均存在直肠侧韧带,其中8具尸体的单侧(6具左侧,2具右侧)、2具尸体的双侧存在直肠中动脉.23例尸体的直肠侧韧带中,直肠神经支是恒定存在的.结论 在直肠与脏筋膜之间存在直肠侧韧带,直肠癌手术中应在脏筋膜与盆丛之间完成直肠侧方的游离.     

直肠全系膜切除术中安全平面的解剖学观察

目的 明确直肠固有筋膜与周围结构的关系,寻找无血管、神经的间隙,为直肠全系膜切除术中＂安全平面＂的选择提供解剖学依据.方法 选择26例10%甲醛固定的成年男性盆腔标本进行研究,20例沿正中切开行局部解剖观察,6例行断层解剖观察.结果 直肠固有筋膜腹侧与Denonvilliers筋膜相邻,共同构成直肠膀胱隔,两者之间为无血管、神经的潜在间隙.直肠固有筋膜背侧与骶前筋膜水平走行,构成无血管、神经的骶前间隙,此间隙解剖变异较大,16例（80%）标本筋膜间隙明显,内有板层状直肠骶骨韧带走行（分层型） 4例（20%）无筋膜间隙,由肌肉样组织填充或骶前筋膜融合、增厚（融合型）.直肠固有筋膜外侧与盆腔壁层筋膜构成直肠外侧间隙,间隙内可见直肠侧韧带和盆腔神经丛,依据神经丛与直肠固有筋膜的关系分为紧密融合型（17例,85%）和疏松连接型（3例,15%）.结论 直肠腹侧的＂安全平面＂介于直肠固有筋膜与Denonvilliers筋膜之间,后外侧位于直肠固有筋膜与壁层筋膜之间.     

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目的通过研究直肠系膜的形态学特点和范围来认识直肠系膜全切除(TME)的理论依据。方法上海交通大学医学院附属瑞金医院对24具尸体的盆腔进行解剖。结果在直肠及周围脂肪周围存在两个相互独立的结构,一个是直肠侧后方的脏筋膜,另一个是直肠前方的Denonvilliers筋膜,它们共同组成了直肠周围的环状筋膜,Denonvilliers筋膜并不能构成直肠系膜的前界。结论TME改善预后的原因并不在于其切除平面为肿瘤难以逾越的"Holy plane",而是在于其完全切除了"直肠腔室"。     

直肠全系膜切除术的前方切除平面

【摘 要】目的 探讨直肠全系膜切除术前方合理的切除平面。 方法 上海交通大学医学院附属瑞金医院对24具尸体的盆腔进行解剖。结果 Denonvilliers筋膜的厚度变化明显,其与精囊的结合比与直肠的结合更为紧密。Denonvilliers筋膜的两侧与盆丛相邻,在5(5/12)具男性尸体中, Denonvilliers筋膜前方有两侧盆丛的交通支。结论 对于非直肠前方的肿瘤,可以采取Denonvilliers筋膜后方的切除平面,以减少自主神经功能损伤。     

Cystocele and functional anatomy of the pelvic floor: review and update of the various theories

Introduction and hypothesis

We updated anatomic theories of pelvic organ support to determine pathophysiology in various forms of cystocele.

Methods

PubMed/MEDLINE, ScienceDirect, Cochrane Library, and Web of Science databases were searched using the terms pelvic floor, cystocele, anatomy, connective tissue, endopelvic fascia, and pelvic mobility. We retrieved 612 articles, of which 61 matched our topic and thus were selected. Anatomic structures of bladder support and their roles in cystocele onset were determined on the international anatomic classification; the various anatomic theories of pelvic organ support were reviewed and a synthesis was made of theories of cystocele pathophysiology.

Results

Anterior vaginal support structures comprise pubocervical fascia, tendinous arcs, endopelvic fascia, and levator ani muscle. DeLancey’s theory was based on anatomic models and, later, magnetic resonance imaging (MRI), establishing a three-level anatomopathologic definition of prolapse. Petros’s integral theory demonstrated interdependence between pelvic organ support systems, linking ligament–fascia lesions, and clinical expression. Apical cystocele is induced by failure of the pubocervical fascia and insertion of its cervical ring; lower cystocele is induced by pubocervical fascia (medial cystocele) or endopelvic fascia failure at its arcus tendineus fasciae pelvis attachment (lateral cystocele).

Conclusions

Improved anatomic knowledge of vaginal wall support mechanisms will improve understanding of cystocele pathophysiology, diagnosis of the various types, and surgical techniques. The two most relevant theories, DeLancey’s and Petros’s, are complementary, enriching knowledge of pelvic functional anatomy, but differ in mechanism. Three-dimensional digital models could integrate and assess the mechanical properties of each anatomic structure.

     

高分辨率MRI显示直肠周围筋膜结构

目的观察直肠周围筋膜高分辨率MRI成像表现。方法对50名正常志愿者行盆腔MRI常规T1WI、T2WI及高分辨率T2WI扫描,观察直肠周围筋膜结构,比较各序列对直肠周围筋膜的显示情况。结果高分辨率T2WI序列对前、后、左、右方直肠系膜筋膜显示率分别98%、100%、94%、90%;对Denonvilliers筋膜、骶前筋膜及腹膜返折显示率分别为58%、54%、70%。高分辨率T2WI对前、左、右方筋膜、Denonvilliers筋膜及腹膜返折的显示率明显高于盆腔常规T1WI、T2WI(P均0.05);对后方直肠系膜筋膜、骶前筋膜显示率略高于常规T1WI、T2WI,但差异无统计学意义(P均0.05)。结论高分辨率T2WI显示直肠周围筋膜结构优于盆腔常规MRI序列。     

全直肠系膜切除术的应用

传统的直肠癌根治术后局部复发是影响术后5年生存率的重要因素之一。近年来解剖学研究证明，直肠是具有系膜的脏器，直肠癌可通过多种方式在系膜中播散，这些微转移灶的残留是导致术后局部复发的重要因素。1982年，Heald首次提出了针对中下段直肠癌的全直肠系膜切除术，即直视下在盆筋膜脏层与壁层间锐性分离，完整切除直肠及直肠系膜，同时注意保护自主神经。经过20年的应用，其在降低直肠癌术后复发方面的优势已得到认可，术后吻合口漏、排尿功能及性功能障碍等并发症发生率低，目前已得到广泛应用。     

直肠癌根治术中是否切除Denonvilliers筋膜的争议与展望

全直肠系膜切除（TME）是中低位直肠癌手术的金标准。传统的TME手术要求在Denonvilliers筋膜前方解剖并切除Denonvilliers筋膜,然而术后居高不下的排尿及性功能障碍发生率引起国内外学者对该理念的争议及质疑。对中低位直肠癌病人,应施行个体化治疗方案。对于肿瘤不位于直肠前壁及侧壁,或肿瘤局部分期较早的病人,应在保证肿瘤根治性的前提下,选择Denonvilliers筋膜后方施行TME手术,尽可能保留Denonvilliers筋膜的完整性,从而保护盆腔自主神经,避免术后排尿及性功能障碍,提高病人术后生活质量。     

结肠癌完整结肠系膜切除术的实践与技术

全直肠系膜切除术(TME)已被公认为是直肠癌的标准化手术技术,但结肠癌手术尚缺乏标准化手术技术.2009年,德国外科医生Hohenberger提出了完整结肠系膜切除术(CME)的概念,认为结肠与直肠周围存在的解剖平面相似,也存在脏壁层筋膜及两者间的疏松无血管间隙,沿该间隙锐性分离,可获得被脏层筋膜完整包被的整个结肠系膜.掌握结肠胚胎发育和解剖是开展CME的前提和基础.CME技术以确保结肠系膜完整、中央血管高位结扎为操作要点.目前多数循证医学证据认为该技术有更好的肿瘤学优势,为CME技术的推广提供了科学依据.北京大学人民医院胃肠外科在国内积极实践推广CME技术,并对CME手术切除范围、淋巴结清扫范围、手术适应证选择、应用解剖等进行了探讨和系列的临床科学研究.     

Laparoscopic-Assisted Modified Intersphincter Resection for Ultralow Rectal Cancer

Background

Intersphincter resection (ISR) is considered to be a superior technique offering sphincter preservation in patients with ultralow rectal cancer.1 Because high-definition laparoscopy offers wider and clearer vision into the narrow pelvic cavity and intersphincteric space, ISR has been further refined.2 However, functional outcome after ISR has not been optimal. More than half of patients receiving ISR suffer partial or even complete anal incontinence.3 We therefore propose a laparoscopic-assisted modified ISR, with the aim of improving sphincter function following ISR.

Methods

The video describes the technique for performing such laparoscopic-assisted modified ISR in a 62-year-old woman with ultralow rectal cancer (3 cm from anal verge). Preoperative staging by endorectal ultrasound and pelvic magnetic resonance imaging revealed stage I rectal cancer (cT₂N₀M₀). The operation consisted of an abdominal and a perineal phase. The abdominal phase routinely involved colonic mobilization with high ligation of inferior mesenteric vessels, total mesorectal excision (TME), as well as transabdominal intersphincteric dissection. The procedure for laparoscopic TME was performed according to our published method.4 Along the TME dissection plane, the puborectalis could be reached and the intersphincteric space was entered posterolaterally. The hiatal ligament at the posterior side of the rectum was transected afterwards. The dissection of the intersphincteric space was continued caudally at the anterior side of the rectum. The distal bowel wall was mobilized for 2 cm from the lower edge of the tumor to obtain adequate distal margin. At this point, circular dissection of the intersphincteric space was completed. After the abdominal phase, perineal dissection was performed with wide exposure by use of a hooked self-retaining retractor. The lower margin of the tumor was identified under direct vision. We developed a modified ISR technique. Resection of the mucosa and internal sphincter was initiated 2 cm distal to the lower edge of the tumor at the tumor side to obtain the necessary distal margin. Meanwhile, at the opposite side of the tumor, the resection line was just above the dentate line so that partial dentate line could be preserved. After removal of the specimen en bloc per anus, the pelvic cavity was generously irrigated with diluted povidone iodine solutions. The distal margin of the specimen was then examined by frozen section for presence of cancer. If clear, coloanal anastomosis was performed using a handsewn technique. The colon was rotated 90° and anastomosed to the anal canal with interrupted absorbable 3–0 sutures. Finally, a pelvic suction drain was placed, and a temporary diverting stoma made in the terminal ileum.

Results

There were no intraoperative complications. The operating time was 180 min. Blood loss was 50 mL. The distal margin was clear, and the final pathology was pT₂N₀M₀. The patient underwent an uneventful recovery. She began sphincter-strengthening exercises 2 weeks after surgery. The stoma was closed after examinations 3 months later. No local recurrence or distant metastasis was found. At 12-month follow-up, in terms of sphincteric function, the patient was continent to solids, liquids, and flatus.

Conclusions

Laparoscopic-assisted modified intersphincter resection for ultralow rectal cancer is safe and feasible. This technique should be considered whenever possible as a means to offer sphincter preservation and improve sphincter function in patients with ultralow rectal cancer.