Anal sphincter function and rectal reservoir after sphincter saving operations for carcinoma of the rectum

Anal sphincter function and rectal reservoir were studied in 27 patients after low anterior resection, in 6 after Welch or Turnbull type pull-through surgery and in 3 after Bacon type pull-through surgery. Sixteen patients who had undergone right hemicolectomy served as a control group. Anal sphincter function immediately after low anterior resection was diminished, but improved during the following 6 months. Rectal capacity was much reduced immediately after surgery, but increased with time, and the neorectum could to some extent adapt to its new role as a reservoir. After pull-through operations, anal canal pressure and rectal compliance were significantly lower than after low anterior resection or right hemicolectomy. These findings may explain the increased frequency of bowel action after pull-through operations.     

Magnetic resonance imaging predicts sphincter invasion of low rectal cancer and influences selection of operation

BACKGROUND: With the development of numerous sphincter-saving surgical techniques in the last 2 decades, the indication for abdominoperineal resection in radical-elective operations has been markedly reduced. The preoperative assessment of the extent of local tumor growth is essential for the planning of the optimal surgical procedure. Magnetic resonance imaging (MRI) proved to be a reliable method for local staging of low rectal carcinoma. The objective of this study was to determine the frequency of sphincter invasion in an unselected population with low rectal cancer. METHODS: From 1997 to 1999, 40 patients with histologically verified adenocarcinoma of the lower rectum (+/-5 cm above the linea dentata) without evidence of metastases underwent a MRI with a body coil (no anal endocoil). The MRI results were compared with the operative situs and with pathohistologic findings. RESULTS: An infiltration of the sphincter ani internus was observed in 11 cases (28%), and a combined infiltration of the sphincter ani internus and externus was found in 2 patients (5%). The median distance of the lower tumor edge to the upper border of the anal canal was 2.0 cm (range, 0-4.5 cm). No infiltration of the external sphincter was observed in patients with cancers above the anal canal. Nine patients (22%) were treated with intersphincteric resection and coloanal anastomosis, 12 (30%) with ultralow resection, and 11 (28%) with low anterior resection of the rectum in conjunction with coloanal anastomosis or a stapled anastomosis. Eight (17%) of the patients were treated with abdominoperineal resection. CONCLUSION: An infiltration of the internal sphincter occurs only in 28% of low rectal cancers; an infiltration of the external anal sphincter is extremely rare and occurred only in patients with cancers located in the anal canal. Pelvic MRI offers a precise preoperative visualization of sphincter infiltration in patients with low rectal cancers and is therefore a valuable tool for planning of rectal surgery.     

改良的经内外括约肌间切除术在超低位直肠癌治疗中的应用

目的:报告经内外括约肌间切除术治疗低位直肠癌的初步结果。方法:对31例瘤灶下缘距离齿状线≤2cm的直肠低位肿瘤进行术前评估,其中18例进展期直肠癌患者先行术前放化疗。腹部手术施行全直肠系膜切除,向下切断骶骨直肠韧带和部分提肛肌达肛门外括约肌环上缘,可沿外括约肌环和肠壁(内括约肌)之间再向下分离1～2cm。肛门手术组在于癌灶下缘2cm之齿状线下方垂直于肛管长轴切开内括约肌全层,然后沿内外括约肌环向上游离,与腹部手术组会师。将近端结肠或结肠贮袋与肛管或肛管齿状线行端端吻合。结果:无手术死亡,31例平均随访12月,29例没有复发和转移。1例证实出现复发和转移,另1例CA19.9增高,但未见转移灶。30例手术后肛门功能较满意。结论:经内外括约肌切除用于超低位直肠癌的保肛手术,可以达到良好的根治性,并保留较好肛门功能。     

Intraoperative endosonography enhances laparoscopy-assisted colon pull-through for high imperforate anus

Purpose: The authors used ultrasonographic endoprobes during laparoscopy-assisted colon pull-through (LACPT) for the repair of high imperforate anus to confirm the pull-through canal was surrounded symmetrically by pelvic floor muscles. Methods: Six patients with high imperforate anus were treated by LACPT (mean age at LACPT, 8.2 months). An endoscopic (12-MHz, 2.5-mm in diameter) and proctoscopic (7.5-MHz, 12-mm in diameter) probe were inserted into the proposed route of dissection intraoperatively to measure the thickness of the surrounding muscle tissue at at least 3 levels: the external anal sphincter, the levator ani muscle sling, and the intervening muscle complex. Results: The average thickness of the external anal sphincter was 2.3 [plusmn] 0.4 mm anteriorly, 2.4 [plusmn] 0.4 mm on the left, 2.4 [plusmn] 0.5 mm posteriorly, and 2.6 [plusmn] 0.6 mm on the right. The average thickness of the muscle complex was 2.3 [plusmn] 0.6 mm anteriorly, 2.2 [plusmn] 0.5 mm on the left, 2.1 [plusmn] 0.4 mm posteriorly, and 2.2 [plusmn] 0.5 mm on the right. The average thickness of the left crus of the levator ani muscle was 1.8 [plusmn] 0.3 mm, the right crus was 1.9 [plusmn] 0.4 mm, and the rim located posterior to the rectum was 2.0 [plusmn] 0.3 mm. No statistically significant difference was found between the measurements taken at each level. Conclusion: Intraoperative endosonography during LACPT can greatly enhance the precision of positioning the pull-through canal.     

中下段直肠癌保肛术201例临床分析

报道１９８６年１月～１９９４年１２月间收治直肠癌患者７８３例，其中，中下段直肠癌５５２例（占７０．５％）。该５５２例中施行各类保肛术２０１例（占３６．４％），其中经腹骶切除５例，经耻骨切除５例，Ｄｉｘｏｎ式６７例，拉下式吻合４４例，拖出式吻合６８例及局部切除１２例。术后３年生存率达９０．９％。文中就保肛手术的根治性、术后排便功能的恢复、并发症的产生和处理以及综合治疗的必要性等问题进行了分析讨论。认为保肛术是治疗中下段直肠癌的一种合理术式，其主要适用于Ｄｕｋｅ’ｓＡ和Ｂ１期病例。采取综合治疗则是预防癌肿复发和提高生存率的重要措施。     

经肛门内外括约肌间切除直肠的直肠癌根治术疗效评价

目的评价经肛门内外括约肌间切除直肠的超低位直肠癌保肛手术的临床疗效。方法总结31例低位直肠癌患者直肠全系膜切除术（TME）加经肛门内外括约肌同切除术的临床资料。结果31例患者肿瘤下缘距齿状线2cm以内，有18例进展期直肠癌患者术前先进行放、化疗。腹部手术施行全直肠系膜切除，向下切断骶骨直肠韧带和部分肛提肌达肛门外括约肌环上缘，沿外括约肌环和肠壁（内括约肌）之间再向下分离1—2cm。肛门手术组在癌灶下缘2cm之齿状线下方垂直于肛管长轴切开内括约肌全层，然后沿肛门内、外括约肌环间隙向上游离，与腹部手术组会师。将近端结肠或结肠储袋与肛管或肛管．齿状线行端端吻合。全组无手术死亡；术后肛门功能恢复较好。平均随访12个月，29例患者无复发和转移；1例出现复发和转移，另1例癌胚抗原19．9，但未发现转移灶。结论经肛门内外括约肌同切除直肠的超低位直肠癌保肛手术可以达到良好的根治性，并保留较好的肛门功能，是一种可选择的根治性保肛手术方法。     

Computerized tomography of the organs of the small pelvis in children with anorectal atresia]

In 12 children with the different forms of anorectal atresia, for studying the state of a sphincter apparatus of the rectum and assessment of quality of its bringing down into the perineum after proctoplasty, computerized tomography of the organs of a small pelvis was used. Underdeveloped and undifferentiated musculus levator ani in children with high anorectal atresia and fistula to the urinary bladder was revealed. The method permits to establish exact location of the intestine brought down relative to musculus levator ani and external anal sphincter.     

直肠拉出切除术治疗低位直肠癌的系列改进

为了提高Ｂａｃｏｎ式直肠拉出切除术后患者的排便控制能力,免去二期手术切除拉出结肠,作者对Ｂａｃｏｎ手术进行了４次改进。第一次保留了肛提肌,第二次保留了齿线和肛管移行区（肛管感觉）,从而大大提高了排便控制能力;第三次改进简化了经肛门的切除操作。第四次改进将拟拉出的结肠端肠管环扎于螺纹内支撑管上,以替代结肠拉出,转流粪便。当环扎线远端肠管坏死脱落时,近侧肠管已与肛管内创面和盆壁靠拢愈合。这就免去二期手术切除肛门外结肠,从而缩短住院期,减轻了患者的痛苦和经济负担。本手术适应于在切除足够的癌远端肠管和周围组织后,肛提肌上剩余直肠不足１ｃｍ,很难经腹腔吻合的低位癌;从而扩大了保肛手术的适应范围。本手术是Ｐａｒｋｓ手术一种很好的替代。     

肛门直肠畸形术后排粪失禁患儿盆腔磁共振成像表现及其临床意义

目的通过肛门直肠畸形术后排粪失禁患儿的盆腔MRI表现,了解盆底肌的形态,直肠、肛管的形态和位置,以及脊髓和骶骨的发育,为分析排粪失禁的原因及制订治疗方案提供客观依据。方法回顾性分析2009年9月至2011年12月间山东大学第二医院收治的34例肛门直肠畸形术后排粪失禁患儿的临床和影像资料,其中男2l例,女13例,年龄3,14岁。应用1．5TMR扫描仪,常规行轴位、冠状位及矢状位扫描,观察肛门括约肌、耻骨直肠肌和提肛肌、直肠、肛管的形态,以及脊髓、骶骨的发育情况。结果MRI检查提示：肛门外括约肌发育不良18例,耻骨直肠肌发育不良23例,肛提肌发育不良27例;直肠位置异常6例,直肠扩张12例,肛直角增大11例;肛管周围脂肪组织5例;合并神经管闭合不全2例,Currarino综合征2例,骶骨发育不全11例,直肠尿道瘘2例。以上影像学结果均经临床最终证实。结论MRI可清楚显示肛门外括约肌、耻骨直肠肌和肛提肌的形态,以及直肠和肛管的形态和位置,同时还可显示脊髓和骶骨的发育情况,是评价肛门直肠畸形术后排粪失禁患儿非常有价值的检查方法。     

Surgery of colorectal cancer

Studies on lymphatic spread of rectal cancer have established the rationale for sphincter preservation in the treatment of midrectal cancer. This entity comprises lesions located 5.5 to 10 cm above the anal verge in women and 7 to 11 cm in men. Abdominosacral resection is a logical means for restoring intestinal continuity after radial resection for midrectal cancer. Direct posterior exposure of the distal limit of resection above the pelvic floor allows accurate construction of the anastomosis without disturbing the anorectal structures or their innervation and maintains essentially normal anal continence. The procedure is preferable to the various pull-through operations. Survival rates for patients undergoing anterior resection, abdominosacral resection and abdominoperineal resection are comparable.     

Technical tips for intersphincteric resection: how to take out the rectum

Intersphincteric resection (ISR) is an ideal technique that preserves the anus, regardless of whether the internal anal sphincter is removed. However, it is difficult to dissect the anterior wall of the rectum from the adjacent organs. We herein describe a safe and useful ISR technique which draws out the rectum through the anus. The intersphincteric space (ISS) between the internal and external anal sphincter muscles was first transabdominally dissected. Next, the transanal dissection was advanced into the ISS bilaterally from the posterior side without dissecting the anterior wall of the anal canal, and the sigmoid colon and rectum were drawn out through the anus. Dissection between the anterior wall of the rectum and prostate/vagina could be easily performed under direct vision. This technique enables the dissection without any risk of a positive surgical margin or unexpected bleeding, and avoids injury to adjacent organs. This technique seems to be a safe and useful dissection technique for approaching the anterior wall of the anal canal.     

Endoscopic polypectomy in the surgical treatment of diffuse polyposis of the large intestine

The article analyses experience in the treatment of 81 patients with diffuse polyposis who underwent subtotal resection of the colon with abdominoanal resection of the rectum and downward displacement of the right parts into the anal canal. It is shown that growth of the remaining occasional polyps and appearance of new polyps are encountered in the maintained parts of the colon and upper parts of the gastrointestinal tract in the postoperative period. The authors found that endoscopic polypectomy allows the right colon to be preserved in 92.6% of cases and the upper digestive tract in 97.5% of cases at a minimum risk of a surgical intervention.     

Feasibility and functional outcome of laparoscopic intersphincteric rectal resection for ultra-low rectal cancer

Aim-Background

The Aim of this study is to evaluate the feasibility and analyze the functional outcome of laparoscopic intersphincteric resection (LISR) in ultra-low rectal cancer. The preservation of anal function following curative operations for low rectal cancer is becoming increasingly important. Laparoscopic intersphincteric resection of the rectum is the utmost sphincter saving operation for rectal cancer. The rectum is laparoscopically resected along with the internal anal sphincter, providing an adequate distal margin for even the ultra-low tumours of the rectum.

Methods

Between 2008 and 2012, nine patients, 2 with a T3 tumour that received preoperative chemoradiotherapy and 7 patients with a non-fixed T2 rectal adenocarcinoma, underwent LISR by a single surgeon. Preoperative tumour staging included endorectal ultrasonography (ERUS) and pelvic MRI. Patients with multiple distant metastases, tumour invasion into adjacent organs and invasion into the external anal sphincter and/or levator ani, were excluded from LISR. Covering ileostomy in seven patients was reversed with a satisfactory functional outcome in each case.

Results

All patients underwent LISR with curative intent. There was no postoperative mortality. Complications included anal stenosis, prolapse of the neorectum and pelvic hematoma. The overall quality of life and functional outcome were deemed satisfactory.

Conclusion

In selected patients, intersphincteric rectal resection may provide an acceptable functional outcome for ultra-low rectal cancer patients, without a permanent stoma.     

Effect of anterior resection on anal sphincter function

Minor difficulties with continence may occur after low anterior resection. Intraoperative injury to the internal anal sphincter or its nerve supply may contribute to this. To study the effect of low anterior resection on the anal sphincter mechanism, anal manometry was performed on 20 patients before and 10 days after resection. Fifteen patients were studied again 6 months after operation. Resting, maximum squeeze and squeeze increment pressures were recorded. Intraoperative manometry (n = 11) and presacral nerve stimulation (n = 6) were performed to determine whether peroperative injury to the internal anal sphincter had occurred. Resting and maximum squeeze anal canal pressures were reduced by low anterior resection, and did not recover. The squeeze pressure increment did not change. Division of the inferior mesenteric artery, full mobilization of the rectum and mesorectum, and rectal transection did not affect resting anal pressure, which was reduced after EEA anastomosis (mean (s.e.m.) before, 40(5) mmHg; after, 27(4) mmHg; P less than 0.05, n = 5). Presacral nerve stimulation produced relaxation of the internal sphincter. Anal sphincter pressures are reduced after low anterior resection. The external anal sphincter and the nerve supply to the internal anal sphincter appear intact. A direct injury to the internal sphincter is postulated.     

Sphincter-saving resection for low rectal cancer

R0 resection, preservation of the anal sphincter, and local control are considered to be the most important target criteria in rectal cancer surgery. Many efforts have been made in recent years to increase the rate of sphincter preservation by performing pull-through operations, ultra-low anterior resection (U-LAR), and intersphincteric resection (ISR). U-LAR is the standard surgery for patients with lower rectal cancer to preserve anal function. Reconstruction in U-LAR is mainly performed using stapled anastomosis. Although conventional coloanal anastomosis makes it possible to preserve the anal sphincter, the mechanical methods are difficult. In that case, almost all the internal sphincter is preserved. The final options for preserving the sphincter are ISR and external sphincter resection (ESR). Although the internal sphincter is sacrificed partially, subtotally, or totally in ISR, and the external sphincter is resected partially or extensively in ESR, complete or incomplete anal function is maintained. However, the literature is not clear regarding long-term oncologic outcome and anal function after these procedures. The application of these surgical techniques can reduce the rate of abdominoperineal resection in very low rectal cancer. The indications for these procedures must be carefully determined based on tumor site and stage as well as the patient's own preference.     

Successful operation for imperforate anus and imperforate rectum: Three year follow-up report

A newborn infant, born with complete absence of the anus, sphincter, anal canal and rectum, was successfully operated upon via proctoplasty eighteen hours after birth, bringing down the sigmoid colon to serve as the new anal canal and rectum. The boy is now three years old and normal in every other respect. The formation of scar in the new anal canal, together with more progressive use of the gluteus maximus muscles, has effectuated very good control of bowel movements. The author has proctoscoped the boy several times during the past year, never finding evidence of the rectal valves, or so-called folds of Houston. This, together with the appearance of the intestinal anatomy at the time of operation, is the basis for the author's conviction that it is not the rectum, but rather the sigmoid colon, which is now functioning as an anal canal and rectum.     

Anatomy of the rectum and anal canal

Collectively, the rectum and anal canal constitute the very terminal segment of the large intestine, and thus of the entire gastro-intestinal tract. Their distal location renders the rectum and anal canal readily accessible to direct inspection and examination. The prime function of the rectum is to act as a distensible reservoir for faeces, while the anal canal incorporates in its wall a powerful muscular sphincter which is of paramount importance in the mechanism of faecal continence. Diseases of the rectum and anal canal, both benign and malignant, account for a very large part of colorectal surgical practice worldwide. This article emphasizes the clinically and surgically relevant aspects of the anatomy of the rectum and anal canal.     

Anal canal melanoma-- case report

Anal canal melanoma is a rare disease comprising 1% of all colorectal ie. anal malignant tumours with very poor long term prognosis. Its significant biologic aggressivity is the consequence of the tendency towards lymphatic, local and hematogenous spread. At the moment of diagnosis even 30% of the patients have distant metastases. Surgical intervention represents the only possibility for cure. Modern approach to the anal canal melanoma treatment implies two types of intervention: wide local excision preserving the sphincter mechanism and abdominoperineal resection of the rectum. There are numerous dillemas about the choice of surgery in particular disease stages. The authors report on a 61 years old women in which anal canal melanoma with left inguinal lymphatic metastases was detected during the inspection of "haemorrhoids". After the diagnosis was established, abdominoperineal resection of the rectum was performed with dissection of both inguinal regions.     

Surgical treatment of complicated extra-sphincter and trans-sphincter fistulas of the rectum]

172 patients were operated for complicated extrasphincter high fistulas and some transsphincter fistulas of the rectum. All the patients were treated by the proposed method--resection of the fistula in intestinal lumen, splitting of the sphincter, repair of anal canal with pullthrough of the distal rectal segment. Spinal anesthesia leading to good relaxation of the anal canal was used. There were no recurrences in patients folloved up during 2 years. Postoperative bed-day reduces to 12-15. There were no disorders of rectal sphincter apparatus.     

Anatomy of the rectum and anal canal

Collectively the rectum and anal canal constitute the very terminal segment of the large intestine, and thus of the entire gastro-intestinal tract. Their distal location renders the rectum and anal canal readily accessible to direct inspection and examination. The prime function of the rectum is to act as a distensible reservoir for faeces, while the anal canal incorporates in its wall a powerful muscular sphincter which is of paramount importance in the mechanism of faecal continence. Diseases of the rectum and anal canal, both benign and malignant, account for a very large part of colorectal surgical practice worldwide. This article emphasizes the clinically and surgically-relevant aspects of the anatomy of the rectum and anal canal.