Lateral Lymph Node Dissection for Locally Advanced Rectal Carcinoma: A Step-by-Step Description of Surgical Anatomical Planes During Cadaveric Dissection and Minimally Invasive Surgery.

PURPOSE: Total mesorectal excision (TME) is accepted as gold standard method in rectal cancer globally. But there is no standard for lateral lymph nodes. Combination of neoadjuvant treatment plus lateral lymph node dissection (LLND) in select patients might be a promising method. Our purpose is to describe the anatomic landmarks of LLND on cadavers and minimally invasive surgery. MATERIALS AND METHODS: Local advanced rectal cancer and lateral lymph node (LLN) metastasis are accepted as an indication of neoadjuvant treatment. LLND was performed according to preoperative imaging after radiochemotherapy. RESULTS: Twenty-eight (10.5%) of 267 patients with rectal cancer who had suspected lateral lymph node metastasis (LLNM) with magnetic resonance imaging (MRI) underwent LLND in addition to TME after neoadjuvant chemoradiotherapy. Eight of them had LLNM. Three patients had bilateral LLND and only 1 had LLNM. The median number of harvested lymph nodes was 6. The rates of LLNM increased with the presence of poor prognosis markers. One regional and 1 distant recurrence were detected in patients who had no LLN metastasis compared with2 regional and 4 distant recurrences in the LLN-positive group. CONCLUSIONS: Local advanced rectal cancer cases may benefit from LLND, but it does not appear to have an effect on overall survival. There is no consensus whether size and/or morphologic criteria in MRI are the ideal guide for LLND.

Computer-based multimodal training module facilitates standardization of complete mesocolic excision technique for right-sided colon cancer: Long-term oncological outcomes.

AIM: The aim of this study is to demonstrate our video training tool developed to teach and standardize complete mesocolic excision (CME) for right-sided colon cancer and also to present our long-term oncological outcomes. METHOD: Educational narrative videos were produced to demonstrate the technical steps of CME. First, a three-dimensional animation video was prepared. Then cadaveric dissections were recorded in a step-by-step fashion, following the sequences of open and minimally invasive surgery. These were followed by videos of real-life demonstrations of surgical procedures, enhanced by superimposed animations of key anatomical structures. In order to demonstrate the impact of this training module on outcomes of patients undergoing CME, we retrospectively queried data from before (2005-2010) and after (2011-2019) implementation of standardized CME in our practice. RESULTS: A total of 180 consecutive patients underwent right hemicolectomy between 2005 and 2019. Fifty-four patients underwent surgery before and 126 patients after CME principles were elaborated and standardized. Of those patients who had surgery after the training module, 58 (46%) underwent open surgery and 68 (54%) underwent laparoscopic colectomy. Demographics, perioperative parameters and morbidity were comparable between the groups. The 5-year overall and disease-free survival rates were significantly improved after implementation of CME training (p = 0.059 and p = 0.041, respectively). Also, 5-year overall and disease-free survival rates for all patients were considerably better than our reported national outcomes. CONCLUSION: Our comprehensive step-by-step training video module for the CME technique demonstrates surgical anatomical planes and important vascular structures and variations. The video also helps standardization of the CME technique and should contribute to improved histopathological and oncological outcomes.

Development and Implementation of a Novel Computer-Based Training Module for the Standardization of Splenic Flexure Mobilization.

BACKGROUND: Computer-based training modules use various multimedia components such as text, graphics, animation, and videos that can theoretically facilitate the learning process. Splenic flexure mobilization (SFM) is a crucial step for tension-free colorectal/anal anastomosis that can be a technically demanding step. This study is designed to demonstrate our novel training module for SFM with high-vessel ligation during surgery and present the anatomical landmarks and embryological plans for SFM. MATERIALS AND METHODS: A step-by-step educational video was prepared to standardize and teach the technical steps of the SFM. 3D animation was prepared and cadaveric dissection was performed in a step-by-step manner similar to minimally invasive surgery. This is followed by the laparoscopic technique. Since we have started this modular training program in our department, a consecutive of 100 patients underwent laparoscopic low anterior resection and coloanal anastomosis with covering stoma. Demographics, characteristics, and postoperative outcomes were evaluated. RESULTS: Surgical anatomical planes and important vascular structures/variations are both shown by 3D animation, cadaveric dissection, and laparoscopic surgery. Out of 100 consecutive cases, there were no mortality, 5 anastomotic leakages 1 of which necessitates reoperation, and 2 splenic injuries which were managed conservatively. CONCLUSION: This unique educational video module for SFM demonstrates surgical anatomical planes and important vascular structures/variations. The employment and implementation of time-independent multimedia components lead to effective training and can theoretically facilitate the learning process.

Redefining the collateral system between the superior mesenteric artery and inferior mesenteric artery: a novel classification.

AIM: The aim of this study was to evaluate the arterial collateral vasculature between the superior mesenteric artery and the inferior mesenteric artery (IMA) from a surgical perspective. METHOD: A total of 107 fresh adult cadavers (94 male) were studied with emphasis on the vascular anatomy of the left colon. Dissections were carried out mimicking the anterior resection technique. The vasculature of the left mesocolon and the collaterals between the superior mesenteric artery and the IMA with respect to their relationship to the inferior mesenteric vein (IMV) were assessed and classified. Collaterals were classified into three different groups: marginal anastomoses (via the marginal = pericolic artery), intermediate mesocolic anastomoses (parallel to the marginal artery but neither adjacent to the IMV nor close to the duodenum) and central mesocolic anastomoses (next to the IMV at the level of the duodenojejunal junction and the lower border of the pancreas). RESULTS: All patients had a marginal anastomosis. However, the marginal anastomosis, as the only anastomosis between the superior and inferior mesenteric arteries at the splenic flexure, was observed in 41 cases (38%). In addition to the marginal artery, intermediate mesocolic anastomoses were found in 49 (46%) and a central mesocolic anastomosis was observed in 17 (16%) of the 107 cases in the splenic flexure mesocolon. It is in this latter variant that collateral vessels can be compromised during ligation/transection of the IMV. CONCLUSION: This new classification can contribute to a precise mesocolic dissection technique and splenic flexure mobilization and help prevent ischaemic damage to the descending colon.

Comparison of Mesenteric Lengthening Techniques in IPAA: An Anatomic and Angiographic Study on Fresh Cadavers.

BACKGROUND: The IPAA technique restores anal functionality in patients who have had the large intestine and rectum removed; however, 1 of the most important reasons for pouch failure is tension on the anastomosis. OBJECTIVE: The aim of this study was to compare technical procedures for mesenteric lengthening used for IPAA to reduce this tension. DESIGN: After randomization, 4 different techniques for mesenteric lengthening were performed and compared on fresh cadavers. SETTING: This was a cross-sectional cadaveric study. MAIN OUTCOME MEASURES: In the first group (n = 5), stepladder incisions were made on the visceral peritoneum of the mesentery of the small intestine. In the second and third groups, the superior mesenteric pedicle was divided, whereas the ileocolic pedicle (n = 7) or marginal vessels (n = 6) were preserved during proctocolectomy. In the fourth group (n = 7), the superior mesenteric pedicle was cut without preserving any colic vessels. Mesenteric lengthening was analyzed. Angiography was performed to visualize the blood supply of the terminal ileum and pouch after mesenteric lengthening. RESULTS: Average mesenteric lengthening was 5.72 cm (± 1.68 cm) in group 1, 3.63 cm (± 1.75 cm) in group 2, 7.03 cm (± 3.47 cm) in group 3, and 7.29 cm (± 1.73 cm) in group 4 (p = 0.011 for group 2 when compared with the others). LIMITATIONS: The study was limited by nature of being a cadaver study. CONCLUSIONS: Stepladder incisions through superior mesenteric pedicle trace are usually sufficient for mesenteric lengthening. In addition, division of the superior mesenteric pedicle with either a preserving marginal artery or without preserving ileocolic and marginal arteries leads to additional mesenteric lengthening.

Variations in the Vascular Anatomy of the Right Colon and Implications for Right-Sided Colon Surgery.

BACKGROUND: Knowledge of the normal pattern and variations of the blood supply of the right colon is crucial for better outcomes after colon surgery. OBJECTIVE: The purpose of this study was to describe the precise vascular anatomy of the right colon according to surgical perspective. DESIGN: Adult fresh cadavers were dissected between January 2013 and October 2015, focusing on the venous and arterial anatomy of the right side of the colon. SETTINGS: Macroscopic anatomical dissections were performed on 111 adult fresh cadavers with emphasis on the vascular anatomy of the right colon. The colic tributaries of the superior mesenteric artery and vein were documented in writing. Furthermore, the dissections were recorded with a video camera. RESULTS: The incidence of colic arteries arising from the superior mesenteric artery included ileocolic artery, 100%; right colic artery, 33.3%; middle colic artery, 100%; and accessory middle colic artery, 11,7%. All 111 cadavers had a single ileocolic vein, which drained into the superior mesenteric vein in 103 cases (92.8%), into the gastro-pancreatico-colic trunk in 7 cases (6.3%), and into the jejunal trunk in 1 case (0.9%). The drainage site of the ileocolic vein to the superior mesenteric vein varied, and in 9% of cases the ileocolic vein did not accompany the ileocolic artery. The gastro-pancreatico-colic trunk was detected in 87 cases (78.4%); with several forms of the origin of the respective branches, the gastropancreatic trunk was detected in 24 cases (21.6), and the classic gastrocolic trunk of Henle was not detected. Variations were found in the formation and drainage routes of other venous colic tributaries of the superior mesenteric vein. LIMITATIONS: This study is limited by its use of cadavers in that it is impossible to trace each vessel to its origin in live surgery. CONCLUSIONS: Surgeons must watch, observe, and bear in mind that vascular variations can occur. Awareness of these complex variations may improve the quality of surgery and may prevent devastating complications during right-sided colon resections.