Right Colic Research Articles

Assessing anatomical variations of the superior mesenteric artery via three-dimensional CT angiography and laparoscopic right hemicolectomy: a retrospective observational study.

This study aimed to analyse the anatomical relationships and differences between the superior mesenteric vessels and their branches by reviewing a laparoscopic right hemicolectomy surgery video and comparing it with preoperative three-dimensional computed tomography (3D-CT) angiography and to verify the accuracy of 3D-CT vascular reconstruction techniques. Surgical videos and preoperative imaging data of 52 patients undergoing laparoscopic right hemicolectomy were analysed to observe and summarize the probability of occurrence and adjacency of superior mesenteric vascular branches, and the lengths of specific sites of their branches were measured using the above two methods. Preoperative CT images and surgical video showed that the ileocolic artery (ICA) was present in 98.1% (51/52) and the ileocolic vein (ICV) was present in 100% (52/52), and ICA was present in 13.7% (7/51) of the ICV directly anteriorly, 13.7% (7/51) anteriorly superiorly, 3.9% (2/51) anteriorly inferiorly, 11.8% (6/51) directly posteriorly, 37.2% (19/51) post superiorly, and 19.7% (10/51) posteriorly inferiorly. In the surgical video, the probability of presence of the right colic artery (RCA) was 21.2% (11/52). On CT images, the RCA was present in 10 patients. The length of the origin of the middle colic artery (MCA) from its bifurcations was 2.33 ± 0.87 cm measured intraoperatively using a sterile isometric filament, and the length measured using 3D-CT vascular reconstruction was 2.36 ± 0.91 cm; the difference was not statistically significant (P = 0.348). The length of the MCA and ICA initiation points was 3.22 ± 0.75 cm measured intraoperatively using sterile isometric filaments and 3.36 ± 0.72 cm measured using 3D-CT vascular reconstruction, which was a statistically significant difference (P < 0.001). 3D-CT vascular reconstruction can accurately predict the vessels related to right hemicolectomy in most cases. It is an important method for preoperative prediction of superior mesenteric vessels, which can guide surgeons in the intraoperative vessel identification.

A SICE (Società Italiana di Chirurgia Endoscopica e Nuove Tecnologie) observational prospective multicenter study on anatomical variants of the superior mesenteric artery: intraoperative analysis during laparoscopic right hemicolectomy-CoDIG 2 database (ColonDx Italian Group).

Colorectal cancer, the third most common cancer worldwide, affects 40-45% of patients on the right side. Surgery, especially minimally invasive methods such as laparoscopic and robotic procedures, is the preferred treatment. However, these techniques present technical complications. The anatomical complexity and variations in vessel branching patterns pose challenges, particularly for less experienced surgeons. The CoDIG 2 is a nationwide observational study involving 76 specialized Italian general surgery departments focused on colorectal surgery. The centres were directed to maintain their standard surgical and clinical practices. The aim of this study was to analyse the intraoperative vascular anatomy of Italian patients who underwent laparoscopic right colectomy and explore the ligature techniques used by Italian surgeons. Surgeons reported information about vascularization of the right colon for 616 patients and about surgical anatomy of RCA for 368 patients. Fifty-three patients (10.8%) showed no RCA intraoperatively. The right colic artery (RCA) was categorized according to the Yada classification (types 1-4) during evaluation, and intraoperative assessments revealed that Yada type 1 was the most common type (55.2%), while radiologic evaluations revealed a higher prevalence of type 2. Furthermore, compared with the superior mesenteric vein (SMV), the RCA is more often located anteriorly according to intraoperative and contrast-enhancedCT examination; 59.9% were found in the anterior position during intraoperative examination, while 40.1% were found in the same position on preoperative contrast-enhanced CT. Vascularization of the right colon, including missing branches, additional branches, shared trunks, and retro-superior courses of the mesenteric vein, exhibited notable variations. To understand vascular variations, a preoperative radiological study is necessary; although there was no concordance between the intraoperative and radiological evaluations, this is a limitation of preinterventional radiological evaluation (PII) because it is always needed for oncological staging. This approach is especially critical for inexperienced surgeons to avoid potential complications, such as problematic bleeding.

Vascularization of the gastrointestinal tract of the bottlenose dolphin (Tursiops truncatus, Montagu 1821).

Odontocetes primarily rely on fish, cephalopods, and crustaceans as their main source of nutrition. In the digestive system, their polygastric complex exhibits similarities to that of their closest terrestrial relatives such as cows, sheep, and giraffes, while the entero-colic tract shares similarities with terrestrial carnivores. The morphology, caliber, and structure of the odontocete intestine are relatively constant, and, since there is no caecum, a distinction between the small and large intestine and their respective subdivisions is difficult. To address this issue, we used the intestinal vascularization pattern, specifically the course and branching of the celiac artery (CA) and the cranial and caudal mesenteric arteries (CrMA and CdMA). A series of pictures and dissections of 10 bottlenose dolphins (Tursiops truncatus) were analyzed. Additionally, we performed a cast by injecting colored polyurethane foam in both arteries and veins to measure the caliber of the arteries and clarify their monopodial or dichotomous branching. Our results showed the presence of multiple duodenal arteries (DAs) detaching from the CA. The CrMA gave origin to multiple jejunal arteries, an ileocolic artery (ICA), and, in six cases, a CdMA. In four specimens, the CdMA directly originated from the abdominal aorta. The ICA gave rise to the mesenteric ileal branches (MIB) and mesenteric anti-ileal branches and the right colic arteries (RCA) and the middle colic arteries. From the CdMA originated the left colic and cranial rectal arteries (LCA and CrRA). The measurements revealed a mixed monopodial and dichotomous branching scheme. The analysis of the arteries and their branching gave us an instrument, based on comparative anatomy, to distinguish between the different intestinal compartments. We used the midpoint of anastomoses between MIB and RCA to indicate the border between the small and the large intestine, and the midpoint of anastomoses between LCA and CrRA, to tell the colon from the rectum. This pattern suggested an elongation of the duodenum and a shortening of the colic tract that is still present in this species. These findings might be related to the crucial need to possess a long duodenal tract to digest prey ingested whole without chewing. A short aboral part is also functional to avoid gas-producing colic fermentation. The rare origin of the CdMA on the CrMA might instead be a consequence of the cranial thrust of the abdominopelvic organs related to the loss of the pelvic girdle that occurred during the evolution of cetaceans.

A systematic review and meta-analysis of variants of the branches of the superior mesenteric artery: the Achilles heel of right hemicolectomy with complete mesocolic excision?

Dissection with subsequent ligation and resection of arteries at their origin (central vascular ligation) is essential for adequate oncological resection during right hemicolectomy with complete mesocolic excision. This technique is technically demanding due to the highly variable arterial pattern of the right colon. Therefore, this study aims to provide a comprehensive evidence-based assessment of the arterial vascular anatomy of the right colon. A thorough systematic literature search through September 2020 was conducted on the electronic databases PubMed, Scopus and Web of Science to identify studies eligible for inclusion. Data were extracted and pooled into a meta-analysis using MetaXl software. A total of 41studies (n=4691 patients) were included. The ileocolic artery (ICA), right colic artery (RCA) and middle colic artery (MCA) were present in 99.7% (95% CI 99.4%-99.8%), 72.6% (95% CI 61.3%-82.5%) and 96.9% (95% CI 94.2%-98.8%) respectively of patients. Supernumerary RCA and MCA were observed in 3.2% and 11.4% respectively of all cases. The RCA shared a common trunk with the ICA and MCA in 13.2% and 17.7% respectively of patients. A retro-superior mesenteric vein course of the ICA and RCA was observed in 55.1% and 11.4% respectively of all cases. The vascular anatomy of the right colon displays several notable variations, namely the absence of some branches (RCA absent in 27.4% of cases), supernumerary branches, common trunks, and retro-superior mesenteric vein courses. These variations should be taken into consideration during right hemicolectomy with complete mesocolic excision to ensure adequate oncological resection while minimizing intra-operative complications.

A Study of the Right Colonic Vascular Anatomy: Correlations between Veins and Arteries.

Objectives: Few studies have examined the correlations between the arteries and veins of the right colon. In this study, we aimed to use high-resolution CT scans to understand the vascular anatomy of Henle's gastrocolic trunk and review the terminology describing the arteries and veins of the right colon. Methods: This retrospective study has examined patients who underwent laparoscopic colectomy for right colon cancer in a single institution in Japan. Scans from consecutive patients who underwent surgery between October 2017 and March 2020 (n = 165) were examined. Preoperative CT images were used to create multiplanar reformation images and volume rendering images. Results: Among the 139 patients with Henle's gastrocolic trunk (GCT) present, arteries accompanying the accessory right colic vein (ARCV) were most common on the right branch of the middle colic artery (MCA) (71.2%), followed by the right colic artery (RCA) (19.4%); meanwhile, 9.4% of the patients had no accompanying arteries. Of patients with no accompanying arteries to the ARCV, RCA was present in 15.4%. Among the 26 patients with no GCT, the right colic vein (RCV) existed in 15 patients, with the artery accompanying the RCV most commonly being the right branch of the MCA (66.6%), followed by the RCA (33.3%). Conclusions: Irrespective of the presence of GCT, approximately 70% of the arteries accompanying the drainage vein from the right colon were the right branch of the MCA. We suggest that vascular branch formation be considered preoperatively in surgical management for right colon cancer.

The use of ultrasound in central vascular ligation during laparoscopic right-sided colon cancer surgery: technical notes.

Complete mesocolic excision (CME) with central vascular ligation (CVL) requires the surgeon to sharply dissect the mesocolon and approach the superior mesenteric artery (SMA) and superior mesenteric vein (SMV) for ligation of the supplying vessels relating to right-sided colon cancer at their origin. Even with preoperative images, it can still be challenging to identify these structures during laparoscopic surgery because of various intraoperative conditions. The aim of this study was to assess the efficacy of intraoperative ultrasound (IOUS) for identification of blood vessels during right-sided colon cancer surgery. We performed IOUS on 19 patients diagnosed with right-sided colon cancer at our institution, in January-October 2020. Preoperatively, a three-dimensional computed tomography (3D-CT) angiogram was obtained for the majority of patients to visualize the SMA, SMV, and their respective branches. The running position of the ileocolic artery (ICA) and right colic artery (RCA) related to the SMV and the presence of the middle colic artery were identified and compared using preoperative 3D-CT, IOUS, and intraoperative findings. Nineteen patients [seven men and 12 women with a mean age of 73.9 ± 8.4years (range 58-82years)] were studied, including some with a body mass index of > 30kg/m2, locally advanced cancer, and severe adhesion. There were IOUSs that detected the SMA, SMV, and their tributaries in all patients. The positional relationships between the SMV and the ICA and RCA revealed by IOUS were consistent with the preoperative and intraoperative findings. IOUS is a safe, feasible, and reproducible technique that can assist in detecting the branching of the SMA and SMV during CME with CVL in laparoscopic right-sided colon cancer surgery, regardless of individual conditions.

English

BACKGROUND Superior Mesenteric Artery (SMA) is one of the anterior branches of the abdominal aorta. It originates from abdominal aorta at the level of lower border of first lumbar vertebra, one centimeter below the coeliac trunk. It gives the first branch inferior pancreaticoduodenal artery (IPDA), The colic branches arise from concave right side of the superior mesenteric artery, these are middle colic artery (MCA), right colic artery (RCA), ileo colic artery (ICA). Jejunal and ileal branches arise from left side of the SMA. Superior mesenteric artery supplies derivatives of midgut. Knowledge of branching pattern of the SMA is clinically important to gastroenterologists operating on gut and neighboring structures like pancreas, duodenum, and liver. We wanted to study the variations in the branches of superior mesenteric artery. METHODS This is a descriptive study conducted on 50 adult embalmed human cadavers by conventional dissection method, the findings were noted and tabulated. RESULTS Present study shows that inferior pancreatic duodenal artery orginated from SMA in 47 (94 %) specimens. IPDA was absent in 3 (6 %) specimens. Middle colic artery was found to arise from SMA in 48 (94 %) and MCA was absent in 2 (4 %) specimens. Right colic artery was found to arise from SMA in 47 (94 %) specimens and it was absent in 3 (6 %) specimens. Ileo-colic artery was found to arise from SMA in all 50 (100 %) specimens. CONCLUSIONS Awareness of these complex variations may prevent devastating complications during colonic surgeries. Variations in the branching pattern of superior mesenteric artery is essential for surgeons operating on derivatives of midgut, liver, pancreas. KEY WORDS Branches, Colic, Superior Mesenteric Artery, Variations

Arterial vascularization of the right colon with implications for surgery.

During right-sided colectomies, surgeons encounter major anatomical variations at the level of the right colon, leading to morbidity. Due to the confusion surrounding the colonic arterial vessels emerging from the superior mesenteric artery (SMA) to vascularize the right part of the colon, this review aimed to describe the arterial vessels found in the mesocolic structures of the ascending colon, the hepatic flexure and the right transverse colon. A review of the literature was performed using the MEDLINE database. Only human studies were included. All dissection, angiographic, arterial cast and corrosion studies were analyzed. This review demonstrates that the right colon, the hepatic flexure and the right transverse colon are vascularized by three significant arteries emerging from the SMA and forming one peripheral paracolic arc: (1) the ileocolic artery (ICA), the most constant vessel (99.8%) with low variability; (2) the right colic artery (RCA), the most inconstant vessel (2/3 of cases) with high variability in its origin; and (3) the middle colic artery (MCA), a constant vessel (95%) with variation in its origin and its number. The marginal artery is almost constant (100%) and represents the only peripheral arterial arc at the level of the right side of the colon. Three arteries emerging from the superior mesenteric artery exist: the ICA, the RCA and the MCA. The ICA and the MCA are the most constant. Knowledge of this vascular anatomy is essential for performing right-sided colectomies.

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.

Key vessels assessment and operation highlights in laparoscopic extended right hemicolectomy

Laparoscopic radical colectomies have been more widely used gradually, among which laparoscopic extended right hemicolectomy is considered as the most difficult procedure. The difficulty of extended right hemicolectomy lies in the need to dissect lymph nodes along the superior mesenteric vein (SMV) and disconnect numerous and possible aberrant vessels. To address this problem, we emphasize two points in key vessel assessment: getting familiar with the anatomy along the medial-to-lateral approach and having a good understanding about the preoperative imaging presentations. An accurately preoperative imaging assessment by abdominal enhanced CT can help the surgeon understand the relative position of the key vessels to be dealt with during operation and the situation of the possible aberrant vessels so as to guide the procedure more effectively and facilitate the prevention and management of the intraoperative complications. During operation, the operator should pay special attention to the management of the vessels in the ileocolic vessel region, Henle's trunk and middle colon vessels. The operation highlights of the key vessels are as follows: (1) The ileocolic vessels: identifying the Toldt's gap correctly and opening the vascular sheath of the SMV securely; making sure that the duodenum is well protected. (2) Henle's trunk: dissecting along the surface of the Henle's trunk; preserving the anterior superior pancreaticoduodenal vein (ASPDV) and main trunk of the Henle's trunk; disconnecting the roots of the right colic vein (RCV) and right gastroepiploic vein (RGEV), and then dissecting lymph nodes along the surface of the pancreas. (3) The middle colon vessels: identifying the root of the middle colon vessel along the lower edge of the pancreas; avoiding entering behind the pancreas; mobilizing the transverse mesocolon sufficiently along the surface of the pancreas. Finally, we discuss and analyze the disputes currently existing in laparoscopic extended right hemicolectomy, including dissection of No.6 lymph nodes, naking the SMA and dissecting lymph nodes around the roots of the branches of SMA. This article shares our experience about laparoscopic extended right hemicolectomy, hoping that it could help beginners master the technique more safely and skillfully.

Variation and treatment of vessels in laparoscopic right hemicolectomy.

With the introduction of complete mesocolic excision (CME) and the application of laparoscopic technique, surgery for colon cancer has become more standardized and the curative effect has improved [1]. The key points in laparoscopic right hemicolectomy are high ligation of main vessels and root dissection of lymph nodes. The wide range of variations in vascular architecture and intraoperative bleeding are common causes of prolonged surgical time, wound hemorrhage, and even transfer to the opening operation. The superior mesenteric vein (SMV) is the most important anatomical landmark in CME for the right colon, and guides all the steps of lymph node dissection. The SMV appears as a pale blue bulge on laparoscopy, which enables accurate positioning. The ileocolic vessel pedicle is relatively constant and facilitates accurate positioning. The intersection of the ileocolic vessel pedicle and the SMV is the optimal starting point in laparoscopic right hemicolectomy using a medial-to-lateral approach. A sheath with an avascular plane can be reached after opening the SMV vascular sheath, which results in less bleeding and enables vascular root and thorough lymph node dissection. The first step is to manage the ileocolic vessels. The ileocolic artery (ICA) is located anterior to the ileocolic vein (ICV) for about one-third of the incidence. The ileocolic vessels are relatively long and are easy to work with. In the vast majority of cases, the ICV drains into the SMV, and into the gastrocolic trunk (GCT) in about 2.5% of cases. The reported incidence of a right colic artery (RCA) is controversial; the RCA is absent in about 50% of cases and often crosses the SMV. The right colic vein (RCV) usually drains into the GCT, but sometimes drains directly into the SMV. The middle colic vessels have great variability and a close anatomical relationship with the pancreas, duodenum, and GCT. Moreover, the transverse colon and mesentery are long, and root positioning and processing of the middle colic vein (MCV) are relatively difficult. With the SMV and pancreas as anatomic landmarks, it is more feasible to locate the blood vessels in the neck of the pancreas. The middle colic artery (MCA) originates from the superior mesenteric artery (SMA), and the distance from the inferior border of the pancreas differs slightly in the literature, but is at the most 5cm. Identification of the MCA trunk and branches, as well as the common origin of the MCA and RCA, is of great importance for the maintaining the blood supply during surgery for primary colon cancer. The MCV mainly drains into the SMV and GCT; however, if branching variation drains into the jejunal vein, inferior mesenteric vein, or splenic vein, the effect is serious when a vessel is torn. Isolation of the GCT is the step at which bleeding will likely occur in standard right resection and is a difficult stage of the surgery. The GCT has five origins including the right gastroepiploic vein (RGV), right colic vein (RCV), accessory right colic vein (ARCV), pancreaticduodenal vein (PDV), and MCV, which can have 2, 3, or 4 branches; therefore, familiarity with variants may be helpful to avoid bleeding. Approximately 5-10% of colon cancers at the hepatic flexure have No. 6 group lymph node metastasis, and laparoscopic radical extended right hemicolectomy requires thorough dissection of No. 6 group lymph nodes and the omental arcade 10cm from the pylorus. The inferior arteriovenous vessels are a common source of bleeding, and the RGV can serve as a clue to finding the artery. The core area of laparoscopic radical extended right hemicolectomy includes the pancreatic neck, duodenum, and right gastroepiploic vessels. The difficulty lies with the standard treatment of the GCT. A medial-to-lateral approach is more in line with the principle of no-touch in tumor surgery and is applied from lower to upper, inside to outside, and left to right, for both the vessels and plane of dissection. Familiarity with vascular variation and the management of vessels in key areas are essential for successful surgery.

The impact of three-dimensional reconstruction on laparoscopic-assisted surgery for right-sided colon cancer.

IntroductionDuring laparoscopic-assisted colorectal surgery (LACS) for right-sided colon cancer patients, we performed three-dimensional (3D) surgical simulation to investigate vascular anatomy, including the ileocolic artery (ICA), right colic artery (RCA) and superior mesenteric vein (SMV).AimWe also used 3D imaging to examine the shortest distance from the root of the ileocolic vein (ICV) to the gastrocolic trunk (GCT).Material and methodsWe analyzed 46 right-sided colon cancer patients who underwent 3D-simulated LACS. We also examined a control group of 20 right-sided colon cancer patients who underwent LACS without 3D imaging. Patients who received such assessments were classified into the following two groups based on the vessel arrangement patterns of the ICA and SMV: the type A group, in which the ICA crosses anterior to the SMV, and the type B group, in which the ICA crosses posterior to the SMV. The shortest length from the root of the ICV to the GCT (D mm) was measured via 3D imaging. Patient characteristics and perioperative outcomes for these three groups were compared.ResultsThe mean D mm for all cases was 29.2 ±5.21 mm. Mean D mm values for the type A and type B groups were 27.8 ±4.21 and 30.5 ±5.53 mm, respectively. Intraoperative blood loss was lower in the type A group (41.8 ±27.5 g) and the type B group (44.5 ±31.6 g) than that in the control group (86.8 ±27.5 g) (p = 0.013).Conclusions3D imaging was useful for understanding anatomical relationships during LACS.

The right colic artery: An anatomical demonstration and its relevance in the laparoscopic era.

INTRODUCTION Hemicolectomies are not tailored in right-sided colon cancer resections, despite significant variation in the incidence and origin of the right colic artery (RCA). Early evidence suggests that removal of the relevant lymphovascular package and associated cancer as part of complete mesocolic excision (CME), rather than the entire right colon, may produce better outcomes. Advancing laparoscopic techniques are making this possible, and so it is increasingly important to more precisely define the anatomy of the RCA. METHODS To demonstrate the incidence and variation of the RCA, 25 formalin embalmed cadavers were dissected. Consent to dissection and photography was obtained under Human Tissue Act regulations. RESULTS Eleven female and 14 male cadavers (mean age 79.7 years, range 41-95 years) were included. The RCA originated from the right branch of the middle colic artery in nine cadavers (36%), while it arose from the superior mesenteric artery in eight cases (32%) and from the ileocolic or root of the middle colic artery in a smaller number of specimens. The RCA was absent in two individuals. CONCLUSIONS The RCA arises from the right branch of the middle colic artery in a considerable number of cases. The literature to date does not reflect the precision of anatomical understanding required for CME; hence, a new definition for the right colic vessel is proposed.

Direct origin of the right colic artery from the abdominal aorta.

An isolated right colic artery originating directly from the abdominal aorta was incidentally observed during diagnostic spinal angiography. Variations in origin of the right colic artery are reviewed, and their embryology and potential clinical implications discussed.

The superior mesenteric artery and the variations of the colic patterns. A new anatomical and radiological classification of the colic arteries.

The superior mesenteric artery (SMA) supplies irrigation to the small intestine, ascending and a variable area of the transverse colon. Although medical imaging and surgical procedures have been widely developed in the last decades, the anatomy of the SMA using advanced imaging technology remains to be elucidated. Previous studies have used small sample sizes of cadaveric or radiological samples to propose a number of classifications for the SMA. In this study, we aimed to provide a more detailed description and useful classification of the SMA and its main branches [middle colic artery (MCA), right colic artery (RCA), and ileocolic artery (ICA)]. Samples (n=50, 28 males and 22 females) were obtained from the repository of human cadavers located at the Department of Human Anatomy and Embryology, Complutense University of Madrid. This sample was dissected by preclinical medical students and completed by two of the authors (Gamo and Jiménez). A second set of samples was obtained from a bank of computerized tomography (CT) (560 CTs, 399 males and 161 females) collected by the Radiology Department at the Clínico San Carlos Hospital, Spain. Based on the results obtained from these studies, we propose a new classification of four patterns for the SMA anatomy. Pattern I as the independent origin of the three main branches of the SMA (cadaveric 40%; CT 73.69%); Pattern II is subdivided in three sub-patterns based on the common trunks of origin: Pattern IIa, common trunk between RCA and MCA (cadaveric 20%, CT 4.28%); Pattern IIb, common trunk between RCA and ICA (cadaveric 32%, CT 15%); Pattern IIc, common trunk for the three main branches (cadaveric 0%, CT 0.35%); Pattern III, as the absence of RCA (cadaveric 8%; CT 2.32%) and Pattern IV, based on presence of accessory arteries (not found in any of the samples). Although the independent origin of the three colic arteries have been classically described as the most frequent, the right colic artery is responsible of major variations.

A Morphometric study of superior mesenteric artery and its implication in laparoscopic Surgery

Introduction: As the field of intestinal surgery advanced over the recent century, challenge of performing more complex resection and anastomoses highlighted the presence of vascular variants. The current clinical interest of these anatomic finding is to laparoscopic colon surgeon. Material and method: The study was conducted on a 50 embalmed human cadavers in the Anatomy dissection hall .We performed detailed dissection to measure length and to note a branching pattern of Superior mesenteric artery and its branches. Results: In all 50 cases Superior Mesenteric Artery (SMA) was originated from abdominal aorta, separated from celiac trunk by 0.9cm + 0.29. All five branches were seen in all samples with 2% showed additional branches. A common trunk of Right Colic artery (RCA) and Middle Colic artery (MCA) was noted in 42%. The numbers of Jejuno-Ilel branches were 7-13 in number with most common was 9 (26%). Additional branch from jejunal artery to other viscera was present in 4%. Mean length of MCA, RCA and Ileo-colic was 3.23 + 1.51, 3.42 + 1.17, and 4.57+ 0.98 respectively. Pattern of distribution noted was Type A 58%, Type B 32%, Type C 10%. Conclusion: A normal pattern of colonic vasculature as accepted by most of medical textbook was not seen in all of the cases. The interest in these anatomical concepts was not simply to Anatomist but also to surgeons while performing a safe and efficient laparoscopic or conventional colon surgery.

Three-dimensional Computed Tomography for Analyzing the Vascular Anatomy in Laparoscopic Surgery for Right-sided Colon Cancer

The mesenteric vessels have many branching patterns. This study clarified the anatomic relationship between the superior mesenteric vein (SMV), the right colic artery (RCA), and the ileocolic artery (ICA) using 3-dimensional computed tomography (3D-CT). The relationship between the RCA and the right colic vein (RCV) was also examined. Between April 2006 and July 2011, all patients with colorectal cancer underwent multidetector computed tomography (MDCT) before laparoscopic surgery. The 100 most recent consecutive cases were analyzed. 3D-CT images were made by combining arterial angiography, venous angiography, colonography, tumor, lymph node, and duodenal images. The RCA branched from the SMA in 37 cases (37%); of these, 21 had an ICA that crossed anterior to the SMV and 16 had an ICA that crossed posterior. When the ICA crossed anterior to the SMV, all had an RCA that crossed anterior to the SMV, and no posterior RCA was seen. Furthermore, the RCV joined the SMV in 10 cases (27%) and the gastrocolic trunk in 27 cases (73%). Our study clarified the anatomic variety of the vessels in right-sided colon cancer. Preoperative 3D-CT is useful for understanding the anatomy to ensure a safe, precise operation.

Vascular anatomy of the right colon and vascular complications during laparoscopic surgery

To analyze the vascular anatomy and complications of the right colon under laparoscope. Videotapes of 55 laparoscopic extended right hemicolectomy with D3 lymphadenectomy were reviewed and the anatomic relationship and bleeding vessels were determined. The superior mesenteric vein, superior mesenteric artery, ileocolic artery, and middle colic artery were present in all the patients. The right colic artery was present in 45.5%(25/55) of the patients. The incidence of the gastrocolic venous trunk was 74.5%. The overall incidence of intraoperative bleeding was 43.6%. Vessels in the pre-pancreatic region including the right gastroepiploic artery, the gastrocolic venous trunk, and its tributaries had a higher risk of bleeding than the middle colic vein and artery (16.4% vs. 14.5%). Intraoperative bleeding significantly prolonged the overall operative time and lymphadenectomy time. The vascular anatomy of the right colon is intricate and variable and laparoscopic extended right hemicolectomy with D3 lymphadenectomy is associated with a high risk of hemorrhage. Understanding the vessels anatomic relationship of the right colon is valuable to decrease vascular complication.

Preoperative evaluation of mesenteric vascular anatomy using 256 multi-slice computed tomography before laparoscopic surgery

To evaluate mesenteric vascular anatomy using 256 multi-slice computed tomography (MSCT) before laparoscopic colorectal surgery. Eleven patients with colorectal cancer underwent 256 MSCT from February 2010 to December 2010. The evaluation items were visualization of mesenteric artery and vein by 3-dimensional CT angiography, which was compared with findings on laparoscopic surgery. Three-dimensional CT angiography correctly demonstrated variations of the mesenteric artery and vein and were consistent with laparoscopic findings. Of the 3 patients undergoing right hemicolectomy, ileocolic artery (ICA) ran ventrally to the superior mesenteric vein(SMV) in 1 patient, whereas ICA ran dorsally to the SMV in 2 patients; the right colic artery (RCA) branched directly from superior mesenteric artery(SMA) in 2 patients; RCA was absent and the left branch of middle colic artery(MCA) fed the tumor in 1 patient. In the patients who had transverse colon resection, MCA branched from SMA. In 2 of 3 patients who underwent sigmoidectomy, sigmoid artery (SA) branched from left colic artery(LCA); in 1 of 3 patients of sigmoid resection, SA branched from inferior mesenteric artery(IMA). In 4 patients with rectal cancer, the superior rectal artery (SRA) fed the tumor. The 256 MSCT is effective for evaluating mesenteric vascular anatomy variation before laparoscopic surgery for colorectal cancer.

Three-Dimensional Vascular Anatomy Relevant to Oncologic Resection of Right Colon Cancer

We analyzed data on the three-dimensional vascular anatomy of the right colon from the operative documents of 215 patients undergoing oncologic resection for right colon cancer. The right colic artery (RCA) was absent in 146 patients (67.9%), with the ileocolic artery (ICA) crossing the superior mesenteric vein (SMV) ventrally in 78 patients (36.3%). When the RCA was present, both the ICA and the RCA crossed the SMV ventrally in 44 patients (20.5%), dorsally in 10 patients (4.7%), the RCA crossed the SMV ventrally and the ICA dorsally in 10 patients (4.7%), and the RCA crossed the SMV dorsally and the ICA ventrally in 5 patients (2.2%). The arterial branches toward the hepatic flexure crossed the SMV ventrally in 151 eligible cases: the branch originated from the common trunk of the middle colic artery in 97 patients (64.2%) and 1 and 2 arteries directly originated from the SMA in 49 patients (32.5%) and in 5 patients (3.3%), respectively. These data would be useful to safely perform lymph node dissection around the SMV.