Toldt's Space Research Articles

Practical membrane anatomy of en bloc mesogastrium excision in lymph node dissection of gastric cancer

Gastric cancer is a common malignant tumor of digestive system. D2 procedure is recognized as the standard operation for advanced gastric cancer at present. However, controversies still exist in the standardization and quality control of surgical procedures. Total mesorectal excision (TME) and complete mesocolic excision (CME) based on the membrane anatomy perfectly solve these problems in the treatment for colorectal cancer. However, the complexity of mesogastrium determines that TME and CME cannot be easily transplanted to the treatment of gastric cancer. The practical membrane anatomy in gastric cancer surgery is just emerging and its impact on the treatment of gastric cancer is immeasurable. By reviewing the evolution and embryonic development of digestive system, and combining with actual operation, this paper analyzes and redefines several key issues such as traditional Toldt space, Gerota fascia and complete mesenteric excision. On this basis, we propose a novel and feasible surgical procedure named regional en bloc mesogastrium excision (rEME) for distal gastric cancer. The concept of en bloc mesogastrium excision (EME) based on membrane anatomy may have some influences on the lymph node grouping from the 'Japanese Classification of Gastric Carcinoma'. Performance of EME may reduce the controversies about the group of lymph nodes and their borders. EME in the infra-pyloric region weakens the significance of subdivision of No.6 lymph nodes into No.6a, No.6v and No.6i. More studies are needed in the construction of a mature theoretical system for practical membrane anatomy in gastric surgery.

Recognition of the interstitial plane of the surgical membrane in radical resection of right semicolon cancer

According to multicenter randomized controlled trials, laparoscopic radical resection of colon cancer has the same short and long term clinical efficacy as traditional open surgery. In laparoscopic radical resection of right semicolon cancer, it is important to separate the embryonic plane of the root, and to ligate and cut off the central vascular roots. Only by separation along the membrane space can one achieve minimally invasive operation with no bleeding, and ensure the integrity of the excision of the mesangium and avoid damage of internal fascia and other organs. The mesangial distribution of the right semicolon is adjacent to the mesangium of the stomach and is connected to the mesentery of the small intestine. The pancreaticoduodenum locates between the right semicolon mesentery and the retroperitoneal subperitoneal fascia. In particular, the relationship between the anterior and posterior Treitz fascia of the pancreaticoduodenum and the Toldt space is complex, which is closely related to the feasibility of complete mesocolic excision(CME). This article introduces the distribution of intermembranous space and mesangial bed in the right semicolon, presenting the problem in CME surgery. In addition, there are key points in identifying the gap between the membranes based on the author's experience and we propose a new evaluation criteria for membrane surgical specimens, which has certain guiding significance for radical CME surgery for right semicolon cancer.

Safety and feasibility of the combined medial and caudal approach in laparoscopic D3 lymphadenectomy plus complete mesocolic excision for right hemicolectomy in the treatment of right hemicolon cancer complicated with incomplete ileus

To explore the safety and feasibility of the combined medial and caudal approach in laparoscopic D3 lymphadenectomy plus complete mesocolic excision(CME) for right hemicolectomy in the treatment of right hemicolon cancer complicated with incomplete ileus. Clinical data of 65 patients with incomplete obstructive right-sided colon cancer (T1 to 4M0) diagnosed by abdominal CT enhanced scan or MRI and/or electric colonscope undergoing laparoscopic right hemicolectomy (D3 lymphadenectomy + CME) at Department of Emergency Medicine and Department of Gastrointestinal Surgery from June 2014 to June 2017 were retrospectively analyzed. Among them, 33 patients received the combined medial and caudal approach (combined medial and caudal approach group) and the other 32 patients received the cephalo medial-to-lateral approach (cephalo medial-to-lateral approach group). The operation highlights of the combined medial and caudal approach group were as follows: (1) The superior mesenteric vein (SMV) was first identified and exposed using the combined medial and caudal approach, and lymph node dissection along the anterior and right of SMV was performed. (2) With horizontal part of duodenum as landmarks, the dorsal mesenteric membrane of terminal ileum was opened by caudal-to-cranial approach, and right retroperitoneal space along the Toldt's space was separated. The anterior of pancreatic head and the right Toldt's space were then exposed. (3) Finally using medial-to-lateral approach, the roots of ileocolic vessels, middle colic vessel and right colic vessel were disconnected and ligated along the left border of SMV. The right branch of gastrocolic trunk of Henle was ligated and lymph node dissection along SMV was performed again. Patients in cephalo medial-to-lateral approach group underwent conventional operation. Baseline information, intraoperative blood loss, operation time, number of harvested lymph nodes, proportion of no less than 12 harvested lymph nodes per case, postoperative hospital stay and postoperative morbidity in both groups were analyzed and compared. Thirty-eight males and 27 females with age of 31 to 72 (56.8±11.7) years were enrolled in this study. There was no significant difference in baseline information between combined medial and caudal approach group and cephalo medial-to-lateral approach group(all P>0.05). Intraoperative blood loss [(106.5±24.5) ml vs. (308.4±27.1) ml, t=-31.501, P=0.000] was significantly less, and operative time [(176.3 ± 18.0) minutes vs. (208.4 ± 47.3) minutes, t=-3.602, P=0.001] was significantly shorter in the combined medial and caudal approach group. The proportion of no less than 2 harvested lymph nodes per case [87.9%(29/33) vs. 84.4%(27/32)], the number of harvested lymph nodes (22.5±8.9 vs. 21.5± 7.6), postoperative morbidity of complication [6.1%(2/33) vs. 12.5%(4/32)] and postoperative hospital stay [(11.9±1.5) days vs. (13.4±4.4) days] were not significantly different between the two groups(all P>0.05). The combined medial and caudal approach in laparoscopic right hemicolectomy (D3+CME) in the treatment of incomplete obstructive right-sided colon cancer is safe and feasible, and has advantages of less intraoperative blood loss and shorter operation time compared to the cephalo medial-to-lateral approach.

Application value of the clearance of No.253 lymph nodes with priority to fascial space and preserving left colic artery in laparoscopic radical proctectomy

To investigate the application value of the clearance of No.253 lymph nodes with priority to fascial space and preserving left colic artery (LCA) in patients undergoing laparoscopic radical proctectomy. From August 2015 to August 2016, 97 consecutive middle-low rectal cancer patients underwent laparoscopic radical proctectomy using the clearance of No.253 lymph nodes with priority to fascial space and preserving LCA at Department of General Surgery, Tangdu Hospital. Among 97 patients, 45 were females , 52 were males, mean age was (64.3±5.5) years and mean BMI was (22.4±1.8) kg/m2. Brief steps of this clearance: traditional medial approach was the commencement of the dissection at the membrane bridge line in front of iliac vascular bifurcation, then entering into the Toldt's space; superior rectal artery served as the top of the tent and the Toldt's space was extended as far as possible; blunt separation was developed caudally (reaching 2 cm below the sacral promontory), cephalad (reaching the lower part of the pancreas), left laterally (reaching Toldt's line), dextrally (reaching abdominal aorta); after giving priority to fascias space, from the root of inferior mesenteric artery, LCA was exposed and No.253 lymph nodes were dissected. This regimen was suitable for the rectal adenocarcinoma patients without distant metastasis. There was no tension in the intestine and mesenteria after anastomosis in all the 97 patients. One patient received LCA ligation during the clearance, because of thinner LCA resulting in bleeding. The other 96 cases completed the clearance and operation successfully. The mean No.253 lymphadenectomy time was 11-27(17.1±5.3) minutes. The mean number of harvested No.253 lymph node was 0-6(4±2). The No.253 lymph nodes of 6 patients were positive. No.253 regional mesentery was complete in 95 patients. The total harvested number of lymph node was 11-26(17.3±5.3). Six patients with positive lymph nodes aged from 68 to 72 years old and all of them underwent TME operation 6-8 weeks after neoadjuvant chemoradiotherapy. The mean operative time was 89-189(125±35) minutes. The mean estimated blood loss was 10.5-38.6(22.4±10.5) ml. The first exhaust time was 3.0-6.0(5.6±2.1) days. The mean time to extracting the drainage tube was 3.0-5.0(4.5±2.5) days. Anastomotic fistula appeared in 1 case and hemorrhage appeared in 1 case, and these 2 cases were cured by conservative treatment. No perioperative death occurred. The mean postoperative hospital stay was 3.0-10.0(3.6±2.6) days. The clearance of No.253 lymph nodes with priority to fascial space and preserving LCA in laparoscopic radical proctectomy is safe and feasible.

Analysis of the common hemorrhage sites during laparoscopic rectal cancer surgery

To analyze the common hemorrhage sites during laparoscopic rectal cancer surgery in order to take reasonable prevention and management. Clinical data of 355 rectal cancer patients who underwent laparoscopic total mesorectal excision in Shanxi Provincial People's Hospital from January 2012 to December 2014 were retrospectively analyzed. Common bleeding sites, blood loss, and hemostasis time were recorded. According to the date of operation, patients were divided into 2012 group (91 cases), 2013 group (122 cases) and 2014 group(142 cases). Hemorrhage rates were compared among three groups. No significant differences were observed in the baseline data among the three groups(all P>0.05). The location in the order of the hemorrhage rate from high to low was seminal vesicle tail (63.0%, 131/208), inferior mesenteric vessels (27.3%, 97/355), Toldt's space (24.2%, 86/355), lateral rectal ligaments (12.1%, 43/355) and post-rectal spatial (8.2%, 29/355). According to the blood loss, post-rectal spatial[(14.1±7.1) ml], inferior mesenteric vessels [(12.7±6.1) ml] and seminal vesicle tail [(12.4±6.5) ml] were ranked in top three. The hemostasis time of seminal vesicle tail [(11.5±6.6) minutes] and post rectal spatial [(10.3±7.8) minutes] was longer than the others. Compared with 2012 group, shorter operative time [(205±50) minutes vs. (235±55) minutes, t=4.296, P=0.001], less blood loss [(35±19) ml vs. (81±24) ml, t=16.243, P=0.001] and lower hemorrhage rate [Toldt's space: 7.7%(11/142) vs. 39.6%(36/91), inferior mesenteric vessels: 9.2%(13/142) vs. 44.0%(40/91), post-rectal spatial: 0.7%(1/142) vs. 15.4%(14/91), lateral rectal ligaments: 2.1%(3/142) vs. 29.7%(27/91) and seminal vesicle tail: 50.6%(41/81) vs. 79.6%(43/54)] were found in 2014 group. The decline of hemorrhage rate in seminal vesicle tail was the slowest (χ2=11.792, P=0.003). The common hemorrhage sites during the laparoscopic rectal cancer surgery are inferior mesenteric vessels, Toldt's space, lateral rectal ligaments, post rectal spatial and seminal vesicle tail. Appropriate preventive measures can ameliorate the intraoperative bleeding significantly, however, more attention should be paid to the seminal vesicle tail during operation because of its higher hemorrhage rate, more blood loss and difficult hemostasis.

Laparoscopic caudal-to-cranial approach for radical lymph node dissection in right hemicolectomy.

The present study evaluated the safety and feasibility of this caudal-to-cranial laparoscopic dissection approach for the curative resection of right-sided colon cancer. To the best of our knowledge, no study has reported the caudal-to-cranial approach in the laparoscopic right colectomy with curative intent for colon cancer. The key procedure of the caudal-to-cranial approach is the commencement of the dissection atthe mesentery root, thus entering into the Toldt's space before the mesenteric vessels are accessed. We retrospectively analyzed the data obtained from a prospectively established database on 80 consecutive patients who had undergone laparoscopic right hemicolectomy with caudally approached radical lymph node dissection for curable right-sided colon cancer between June 2014 and June 2015. There were 38 male and 42 female patients, with a mean age of 72.5years (range, 53-83) and a mean BMI of 22.1kg/m(2) (16.5-35.2). All procedures were successful without any serious intraoperative complications or any conversion to open surgery. The mean operation time was 178.3min (range, 150-215), and the mean blood loss was 81.6ml (range, 50-200). The mean number of harvested lymph nodes was 19 (range, 12-25). The findings indicate that laparoscopic caudal-to-cranial approach for radical lymph node dissection is a feasible and safe procedure for the treatment of curable right-sided colon cancer.

Laparoscopic pancreaticoduodenectomy: right-inferior-posterior "artery first" approach

To discuss the application of right-inferior-posterior "artery first" approach in laparoscopic pancreaticoduodenectomy. Clinical data of 17 patients who underwent laparoscopic pancreaticoduodenectomy through right-inferior-posterior "artery first" approach in our department from February 2014 to April 2015 were retrospectively analyzed. The operation began at the inferior flexure of duodenum. After entering the Toldt's space, the left renal vein (LRV) was revealed and the root of superior mesenteric artery (SMA) was exposed just above the LRV. SMA was dissected along its trunk till the horizontal part of duodenum. Of these 17 cases, adenocarcinoma of pancreatic head was observed in 5 cases, adenosquamous carcinoma in 2 cases, mucinous cycstic neoplasm in 1 case, adenocarcinoma of lower common bile duct in 4 cases, and duodenal papilla cancer in 5 cases. Fifteen cases were accomplished successfully with laparoscopy and 2 cases were converted to open approach. The average operating time was (320 ± 85) min and mean intraoperative blood loss was (305 ± 175) ml. The cutting margins were tumor negative in all the patients. The average number of harvested lymph node was 15.4 ± 6.5. Postoperative complication occurred in 5 cases. Two cases of bile leakage and 2 cases of pancreatic fistula were cured with conservative treatment. One case of delayed abdominal hemorrhage was resolved with reoperation. Right-inferior-posterior "artery first" approach is safe and feasible in laparoscopic pancreaticoduodenectomy.

Nerve-guided laparoscopic total mesorectal excision for distal rectal cancer.

Urogenital dysfunctions are well-recognized problems after rectal cancer surgery and are often due to autonomic nerve damage. Although following holy planes during total mesorectal excision (TME) reduces the possibility of damage to the autonomic nerve fibers, these could still be affected in some critical areas.1 (,) 2 To improve the quality of surgery and prevent nerve damage, accurate intraoperative anatomical orientation of autonomic nerve is essential.3 Thanks to advancement of the high-definition laparoscopic technology, even the finest nerve fibers deep in the pelvic cavity can be identified through illumination and magnification.4 We aim to present a surgical technique of using the autonomic nerves as landmarks to guide laparoscopic TME for distal rectal cancer, with the purpose of preventing autonomic nerve damage to the largest extent. The video describes the technique of performing nerve-guided laparoscopic TME in a 50-year-old man with a rectal cancer (7cm from anal verge). Preoperative staging by endorectal ultrasound and pelvic magnetic resonance imaging is stage I rectal cancer (cT2N0M0). Five trocars (two 12mm and three 5mm) are used. All procedures are performed with conventional laparoscopic instruments. The sigmoid colon is mobilized using a medial approach. The superior hypogastric plexus lies just posterior to the inferior mesenteric artery (IMA) are clearly identified and protected. Then the root of the IMA is ligated and cut. The left Toldt space is dissected, followed by complete mobilization of the sigmoid colon. The superior hypogastric plexus nerve fibers combine to a strong pair of hypogastric nerves as they enter the pelvic cavity, and can be clearly identified when the mesorectum is lifted. Then the mesorectum is separated from the hypogastric nerves by sliding down along the nerves. Dissection of the mesorectum is continued in the loose areolar plane along the midline down to the sacrococcygeal junction. Then the mesorectum is dissected laterally from posterior midline up to 9 o'clock on the left and to 3 o'clock on the right side. The splanchnic nerves can be identified as they swing from the sacrum and straight into the pelvic plexus. The peritoneum is dissected in an arc line about 0.5cm above the line of rectovesical pouch. After the anterior side of the rectum is mobilized, the mesorectum is dissected along the seminal vesicles downward and sideward to the lateral margin. The neurovascular bundle of Walsh at the anterolateral side of the rectum is clearly identified and protected. The mobilization of the mesorectum ceases at the tendinous arch of levator ani. Then the rectum is only fixed to the pelvic side wall by its lateral ligaments, which are consisted by rectal branch of the inferior pelvic plexus and vessels. Thus care should be taken to cut only those rectal nerve fibers, leaving the inferior pelvic plexus intact. The mesorectum is divided 5cm distal to the lesion with one firing of an endoscopic stapler. The specimen is extracted through a 3cm transumbilical laparotomy. End-to-end anastomosis using a circular stapler is performed intra-abdominally. There were no intraoperative complications. The operating time was 160min. Blood loss was 20mL. The patient underwent an uneventful recovery and was discharged home on postoperative day 6. Final pathology was pT2N0M0. At 6-month follow-up, the patient had no urogenital dysfunctions. Nerve-guided laparoscopic total mesorectal excision for distal rectal cancer is safe and feasible. This technique should be considered whenever possible as a means to prevent autonomic nerve damage and subsequent loss of urogenital function.

Laparoscopic extended right hemicolectomy with D3 lymphadenectomy using a medial-to-lateral approach

Lapareseopic colectomy is commonly performed,but laparoscopic extended right hemicolectomy with D3 lymphadenectomy for cancer located at hepatic flexure of the colon is a complex procedure,even in the hands of experts.Laparoscopic dissection of the lymph nodes around the middle colonic and right gastroepiploic vessels are so complicated that precise vascular anatomy and surgical plane are essential to complete this procedure safely.We herein describe a standard technique for performing laparoscopic extended right hemicolectomy with D3 lymphadenectomy using a medial-to-lateral approach.The main surgical plane of this procedure is the right Toldt's space.The superior mesenteric vein (SMV) is the most important anatomical landmark of vascular dissection.Medial-to-lateral approach makes it easy to locate the right Toldt's space and the SMV. Key words: Colonic neoplasms ; Laparoscopy ; Extended right hemicolectomy ; Anatomical landmark ; Complete mesocolic excision ;

Perirectal Fascia and Spaces: Annular Distribution Pattern Around the Mesorectum

In view of debate on the optimal surgical planes for total mesorectal excision, this study was designed to explore the regional anatomy of the perirectal fascia and spaces. Twenty-one cadavers (15 male and 6 female) were embalmed and their vessels visualized by injection with color dye. From the cadavers, 30 hemipelves and 6 three-quarter pelves were harvested. The perirectal fascia and spaces and the pelvic autonomic nerves were dissected and examined. Three tissue layers were dissected from the inside to the periphery: the proper rectal fascia enveloping the mesorectum, the presacral fascia, and the piriformis fascia fused with the sacral periosteum. The mesorectum comprised 2 parts: posterior, with the classical posterolateral fat covered by the proper rectal fascia; and anterior, with the anterior fat covered by the posterior layer of Denonvilliers fascia. Extending anteriorly to the anterior layer of Denonvilliers fascia, the presacral fascia bisected the space between the mesorectum and the piriformis fascia into the retrorectal space and the presacral space. The retrorectal space extended cranially to the left Toldt's space, anterior to the space between the 2 layers of Denonvilliers fascia. From the inside to the periphery, the proper rectal fascia, the presacral fascia, and the muscular fascia are distributed in an annular pattern around the mesorectum. The presacral fascia divides the perirectal space into 2 annular parts: the central retrorectal space and the peripheral presacral space. The retrorectal space is the ideal surgical plane for the total mesorectal excision.