Unveiling the hidden: identification and management of overlooked blood vessels in laparoscopic left hemicolectomy for splenic flexure cancer

BACKGROUND

During laparoscopic left hemicolectomy procedures, a previously overlooked consistently thick blood vessel within the gastrocolic ligament near the splenic hilum may contribute to post-operative bleeding complications. The purpose of this study was to investigate the identification and management of the previously overlooked blood vessel.

METHODS

This is a retrospective descriptive study of patients undergoing laparoscopic left colectomy for splenic fexure cancer conducted at a national gastrointestinal surgery centre in China. Consecutive patients with splenic fexure cancer who underwent laparoscopic left colectomy using our"five-step process"(n = 34) between January 2021 and July 2023 were included.

RESULTS

The vessels can be effectively exposed using the aforementioned "five-step process." It was observed that the overlooked vessels consistently present in all patients were identified as the omental branch of the left gastroepiploic artery and vein.

CONCLUSION

We have identified the origin of previously overlooked blood vessels and recommended a safe method for their management. This may offer advantages to colorectal surgeons performing laparoscopic left colectomy for splenic flexure cancer.

Clinical outcomes and radiological assessment of vascular anatomy in patients who underwent D3 left hemicolectomy

Background

Adequate blood supply is one of the key factors for colorectal anastomosis healing. Various variants of vascular anatomy often come as a surprise to surgeons during operations.

Objectives

The aims of this study were to carry out a comparative analysis of three-dimensional-computed tomography (3D-CT) angiography data with intraoperative data and a detailed analysis of variants of the anatomy of splenic flexure.

Material and methods

In this study, we included 103 patients (56 males and 47 females; mean age 64.2 ± 11.6) with the left-sided colon and rectal cancer who underwent preoperative 3D-CT angiography at Ternopil University Hospital between 2016 and 2022.

Results

According to the recently proposed classification, there are four types of blood supply to the splenic flexure of the colon: Our analysis showed that type 1 was found in 83 (80.6%) patients, type 2 in 9 (8.7%), type 3 in 10 (9.7%), and type 4 in 1 (1%). All patients underwent local left radical hemicolectomy with resection of complete mesocolic excision (CME), central vascular ligation (CVL) and resección (R0). Seven cases were operated laparoscopically; and the median quantity of removal lymph nodes was 21.54 ± 7.32. Positive lymph nodes were revealed in 24.3% cases. AL was diagnosed in one patient.

Conclusions

Careful pre-operative analysis of vascular anatomy on 3D-CT angiography will assess the vascularization of the splenic flexure of the colon, reduce intraoperative time to identify structures, and develop a personalized strategy for surgery which potentially can reduce the risk of anastomotic leakage.

Drainage pattern of the splenic flexure vein and its accompanying arteries using three-dimensional computed tomography angiography: a single-centre study of 600 patients

AIM

The splenic flexure has variable vascular anatomy, and the details of the venous forms are not known. In this study, we report the flow pattern of the splenic flexure vein (SFV) and the positional relationship between the SFV and arteries such as the accessory middle colic artery (AMCA).

METHODS

This was a single-centre study using preoperative enhanced CT colonography images of 600 colorectal surgery patients. CT images were reconstructed into 3D angiography. SFV was defined as a vein flowing centrally from the marginal vein of the splenic flexure visible on CT. AMCA was defined as the artery feeding the left side of the transverse colon, separate from the left branch of the middle colic artery.

RESULTS

The SFV returned to the inferior mesenteric vein (IMV) in 494 cases (82.3%), the superior mesenteric vein in 51 cases (8.5%) and the splenic vein in seven cases (1.2%). The AMCA was present in 244 cases (40.7%). The AMCA branched from the superior mesenteric artery or its branches in 227 cases (93.0% of cases with existing AMCA). In the 552 cases in which the SFV returned to the IMV, superior mesenteric vein or splenic vein, the left colic artery was the most frequent artery accompanying the SFV (42.2%), followed by the AMCA (38.1%) and the left branch of the middle colic artery (14.3%).

CONCLUSIONS

The most common flow pattern of the vein in the splenic flexure is from the SFV to IMV. The SFV is frequently accompanied by the left colic artery or AMCA.

Re-interpreting mesenteric vascular anatomy on 3D virtual and/or physical models, part II: anatomy of relevance to surgeons operating splenic flexure cancer

BACKGROUND

The splenic flexure is irrigated from two vascular areas, both from the middle colic and the left colic artery. The challenge for the surgeon is to connect these two vascular areas in an oncological safe procedure.

MATERIALS AND METHODS

The vascular anatomy, manually 3D reconstructed from 32 preoperative high-resolution CT datasets using Osirix MD, Mimics Medical and 3-matic Medical Datasets, were exported as STL-files, video clips, stills and supplemented with 3D printed models.

RESULTS

Our first major finding was the difference in level between the middle colic and the inferior mesenteric artery origins. We have named this relationship a mesenteric inter-arterial stair. The middle colic artery origin could be found cranial (median 3.38 cm) or caudal (median 0.58 cm) to the inferior mesenteric artery. The lateral distance between the two origins was 2.63 cm (median), and the straight distance 4.23 cm (median). The second finding was the different trajectories and confluence pattern of the inferior mesenteric vein. This vein ended in the superior mesenteric/jejunal vein (21 patients) or in the splenic vein (11 patients). The inferior mesenteric vein confluence could be infrapancreatic (17 patients), infrapancreatic with retropancreatic arch (7 patients) or retropancreatic (8 patients). Lastly, the accessory middle colic artery was present in ten patients presenting another pathway for lymphatic dissemination.

CONCLUSION

The IMV trajectory when accessible, is the solution to the mesenteric inter-arterial stair. The surgeon could safely follow the IMV to its confluence. When the IMV trajectory is not accessible, the surgeon could follow the caudal border of the pancreas.

Standardize the Surgical Technique and Clarify the Relevant Anatomic Concept for Complete Mobilization of Colonic Splenic Flexure Using da Vinci Xi® Robotic System

BACKGROUND

The present study is to set up a standardized approach for complete mobilization of colonic splenic flexure using da Vinci Xi^® robotic system, based on clarification of the mesenteric structures of distal transverse colon.

METHODS

The surgical outcomes and relevant anatomic structures of 104 consecutive patients undergoing robotic resection of primary colorectal cancer with the intent of complete mobilization of colonic splenic flexure using da Vinci Xi^® robotic system were retrospectively reviewed.

RESULTS

Complete mobilization of colonic splenic flexure can be efficiently performed by the Xi^® robotic system, as demonstrated by short operation time, minimal intra-operative blood loss, and few surgical complications. Xi^® robotic system has overcome the drawbacks of Si^® robotic system for the mobilization of colonic splenic flexure. The present study defined the following anatomic hallmarks for the colonic splenic flexure: (1) The transverse mesocolon distal to the inferior mesenteric vein adheres to the low border of pancreas by the avascular fibrous connective tissues, which have been inappropriately named as "mesenteric root"; (2) The colonic splenic flexure abuts closely to spleen with an acute angle in 78.85% (n = 82/104); (3) Only a minority of patients presented with the Riolan branch (15.38%, n = 16/104) or the Moskowitz artery (8.65%, n = 9/104).

CONCLUSION

With increased maneuverability of Xi^® robotic arms and the clarification of relevant anatomic concept, the surgical technique for the complete mobilization of colonic splenic flexure can be standardized; and the standardization of surgical technique is the first step toward the enhanced automation in the rapidly evolving robotic systems.

Vascular anatomy of the transverse mesocolon and bidirectional laparoscopic D3 lymph node dissection for patients with advanced transverse colon cancer

Laparoscopic D3 lymph node dissection for transverse colon cancer is technically demanding because of complicated anatomy. Here, we reviewed the vascular structure of the transverse mesocolon, explored the extent of the base of the transverse mesocolon, and evaluated the feasibility and oncological safety of D3 lymph node dissection. We retrospectively reviewed the clinical records of 42 patients with advanced transverse colon cancer who underwent curative surgery and D3 dissection at Kyushu University Hospital between January 2008 and December 2015. We examined the venous and arterial anatomy of the transverse mesocolon of each resection and compared surgical outcomes between patients who underwent laparoscopic D3 (Lap D3) and open D3 (Open D3) dissection. Patients included two with Stage I, 18 with Stage II, 20 with Stage III, and two with Stage IVA. Thirty-six (85.7%) and six (14.3%) patients underwent Lap D3 or Open D3, respectively. The tumor sizes of the Open D3 and Lap D3 groups were 7.8 and 3.7 cm, respectively (P < 0.001). The Lap D3 group had significantly less blood loss (26 mL vs 272 mL, P = 0.002). The other outcomes of the two groups were not significantly different, including 3-year overall survival (87.7% vs 83.3%, P = 0.385). We observed four patterns of the middle colic artery (MCA) arising from the superior mesenteric artery (SMA), and the frequency of occurrence of a single MCA was 64.3%. The right-middle colic vein (MCV) was present in 92.9% of resections and served as a tributary of the gastrocolic trunk, and 90.5% of the left MCVs drained into the superior mesenteric vein (SMV). The root of the transverse mesocolon was broadly attached to the head of the pancreas and to the surfaces of the SMV and SMA. Laparoscopic D3 lymph node dissection may be tolerated by patients with advanced transverse colon cancer.

Aberrant celio-mesenteric supply of the splenic flexure: Provoking a bleed

Lower gastrointestinal hemorrhage presents a common indication for hospitalization and account for over 300000 admissions per year in the United States. Multimodality imaging is often required to aid in localization of the hemorrhage prior to therapeutic intervention if endoscopic treatment fails. Imaging includes computer tomography angiography, red blood cell tagged scintigraphy and conventional angiography, with scintigraphy being the most sensitive followed by computer tomography angiography. Aberrant celio-mesenteric supply occurs in 2% of the population; however failure to identify this may result in failed endovascular therapy. Computer tomography angiography is sensitive for arterial hemorrhage and delineates the anatomy, allowing the treating physician to plan an endovascular approach. If at the time of conventional angiography, the active bleed is not visualized, but the site of bleeding has been identified on computer tomography angiography, provocative angiography can be utilized in order to stimulate bleeding and subsequent targeted treatment. We describe a case of lower gastrointestinal hemorrhage at the splenic flexure supplied by a celio-mesenteric branch in a patient and provocative angiography with tissue plasminogen activator utilized at the time of treatment to illicit the site of hemorrhage and subsequent treatment.

Pharmacological modulation of gut mucosal and large vessel blood flow

BACKGROUND

Constipation, diminished gut blood flow, ischaemic colitis and drug therapy may be associated.

AIM

To study the effect of constipating medication on, and the regulation of, gut blood flow.

METHODS

24 healthy females (mean age 30) received, in a double-blind, three-way crossover study: (i) placebo, (ii) ipratropium 40 microg by inhalation (positive control known to reduce rectal mucosal blood flow) and (iii) oral loperamide 4 mg. Mucosal blood flow was measured at the splenic flexure and rectum using laser Doppler flowmetry. Blood flow in the superior and inferior mesenteric arteries was measured by trans-abdominal Doppler ultrasound.

RESULTS

Ipratropium decreased rectal mucosal blood flow by 16% (P=0.009) and splenic flexure mucosal blood flow by 8% (P=0.075). Loperamide caused no change in rectal (P=0.40) or splenic flexure mucosal blood flow (P=0.73). Neither treatment changed superior or inferior mesenteric artery blood flow. Splenic flexure mucosal blood flow showed a positive correlation with rectal mucosal blood flow (r=0.69; P<0.0001).

CONCLUSIONS

Vasoactive agents may reduce gut mucosal blood flow in the absence of reduced large vessel flow. Constipating drugs do not necessarily reduce gut blood flow. Rectal mucosal blood flow correlates with splenic flexure mucosal flow, and potentially may be used as a more convenient surrogate for studying splenic flexure blood flow.

A rare case of distal one-third of the transverse colon supplied by a branch from splenic artery

We observed a rare variation of splenic artery during the routine dissection in the Laboratory of the Anatomy Department. It arose from the splenic artery toward the distal part of transverse colon which typically supplied by the inferior mesenteric artery. Embryologically distal part of the transverse colon is a segment of hindgut. In this case, splenic artery which an artery of foregut supplies an area of hindgut. The knowledge of splenic artery variations has significant importance during surgery of the organs of the upper abdominal region. In this study, we discussed clinical significance and embryological aspects of this anomalous artery.