Gastrocolic trunk of Henle and its variants: review of the literature and clinical relevance in colectomy for right-sided colon cancer

Impact of double-bolus tracking to individualize scan timing of the portal venous phase in preoperative computed tomography colonography angiography for right-sided colon cancer

AIM

In computed tomography colonography angiography (CTC-A), used for preoperative screening of right-sided colon cancer, the timing of venous phase imaging is conventionally determined by a fixed-delay time; however, the contrast effect may be insufficient because of individual differences in blood flow status. Therefore, we developed the double-bolus tracking (DBT) method to solve this issue.

METHOD

We compared the contrast effect and image quality of the portal venous systems between two methods of the conventional fixed-delay and DBT which utilizes low-dose monitoring to individualize venous scan timings. Data from 30 consecutive patients who underwent CTC-A for right-sided colon cancer using the DBT method were prospectively collected and compared with that from 30 consecutive patients who underwent the conventional fixed-delay method between August 2018 and July 2022. CT values of the portal vein, gastrocolic trunk, and middle colic veins were measured. Additionally, two gastrointestinal surgeons performed a five-point visual evaluation of the three-dimensional volume rendering image of the gastrocolic trunk.

RESULTS

CT values in the DBT group were significantly higher than those in the fixed-delay group. (portal vein: 266.7 HU vs. 210.0 HU; p <  0.001, gastrocolic trunk: 251.6 HU vs. 191.0 HU; p <  0.001, middle colic vein: 257.2 HU vs. 190.1 HU; p <  0.001). Visual assessment of the gastrocolic trunk was significantly higher in the DBT group than that in the fixed-delay group (DBT, 3.6, 3.4; fixed-delay, 2.6, 2.8; p =  0.003, p =  0.044).

CONCLUSION

The DBT method can enhance the contrast effect of the portal venous systems and improve image quality.

'Head-first Approach' for small duct chronic pancreatitis

Small duct pancreatitis is a rare variant of chronic pancreatitis characterized by a main pancreatic duct (MPD) measuring less than 5 mm. Traditionally, resectional procedures have been advocated as a treatment for small duct pancreatitis. However, these procedures are associated with worse post-operative results and a gradual functional decline over the long term. Parenchyma-preserving hybrid extended drainage procedures have been shown to provide more comprehensive pain relief, improved functional outcomes, and enhanced quality of life (QOL). However, the identification of the MPD in these patients presents a technical challenge. We describe the 'head-first approach' for the identification of the MPD in patients with small duct pancreatitis undergoing extended drainage procedures. The study includes patients of small duct pancreatitis who underwent the extended drainage procedure during a 6-year period from April 2017 to March 2023. During the study period, 41 patients underwent surgical management for chronic pancreatitis. Thirty-two patients underwent an extended drainage procedure, with pain being the indication for surgery in all cases. Twelve of these patients had small duct disease. The 'head-first approach' for identification of the MPD was successfully employed in all 12 patients. The median blood loss during surgery was 180 mL, and the median duration from the beginning of head coring to the identification of the duct was 45 min. Of the 32 patients, post-operative bleeding was seen in 4, external pancreatic fistula was observed in 2, and superficial surgical site infection was seen in 2 patients. All four patients with bleeding were managed conservatively with blood transfusions, and no re-explorations or re-interventions were required. There were no mortalities in this cohort. The 'head-first approach' for pancreatic duct identification is a safe and feasible technique to enable an extended drainage procedure with all the advantages of a parenchyma-preserving procedure for surgical palliation of pain in small duct chronic pancreatitis.

Clinical application of three-dimensional printing technology in laparoscopic right hemicolectomy for colon cancer: a pilot study and video demonstration

BACKGROUND

Patients who undergo laparoscopic right hemicolectomy often have vascular anomalies, creating challenges for surgeons. Preoperative identification of vascular anomalies and intraoperative precise navigation can enhance surgical safety and reduce the difficulty of the procedure. Accordingly, this study aimed to explore and evaluate the application of three-dimensional (3D) reconstruction and printing technology in laparoscopic right hemicolectomy and its assistance in preoperative planning and intraoperative navigation.

METHOD

11 3D-reconstructed images and printed models of right hemicolectomy vasculature were preoperatively created to assist in developing individualized surgical plans. Intraoperatively, essential vessels (gastrocolic trunk of Henle, GTH) were identified and located with the help of the 3D printed models. Additionally, 36 cases without the assistance of 3D printing were retrospectively collected for the control group. Statistical analysis was performed to evaluate the impact of the 3D printed models on surgery-related characteristics.

RESULTS

The 3D-printed models accurately depicted anatomical structures, particularly the positions and adjacent relationships of essential vessels, including the superior mesenteric artery (SMA), superior mesenteric vein (SMV), GTH and related arterial/venous branches. The operation time was significantly lower in the 3D printing group (198.6 ± 8.8 min in 3D printing group vs. 230.7 ± 47.5 min in control group, P = 0.025).

CONCLUSIONS

In conclusion, this study represents a novel vascular 3D printed modelfor surgical planning and intraoperative navigation in laparoscopic right hemicolectomy. It underscores the potential clinical applications of 3D printing in this context. Preoperative identification of vascular anomalies and precise intraoperative navigation can feasibly reduce surgical difficulty and enhance safety.

The use of mixed reality in the preoperative planning of colorectal surgery: Preliminary experience with a narrative review

New advanced technologies have recently been developed and preliminarily applied to surgery, including virtual reality (VR), augmented reality (AR) and mixed reality (MR). We retrospectively review all colorectal cases in which we used holographic 3D reconstruction from February 2020 to December 2022. This innovative approach was used to identify vascular anomalies, pinpoint tumor locations, evaluate infiltration into neighboring organs and devise surgical plans for both training and educating trainee assistants. We have also provided a state-of-the-art analysis, briefly highlighting what has been stated by the scientific literature to date. VR facilitates training and anatomical assessments, while AR enhances training and laparoscopic performance evaluations. MR, powered by HoloLens, enriches anatomic recognition, navigation, and visualization. Successful implementation was observed in 10 colorectal cancer cases, showcasing the effectiveness of MR in improving preoperative planning and its intraoperative application. This technology holds significant promise for advancing colorectal surgery by elevating safety and reliability standards.

Multidetector computer tomography and magnetic resonance imaging of double superior mesenteric veins: A case report

BACKGROUND

This study aimed to describe the findings of double superior mesenteric veins (SMVs), a rare anatomical variation, on multidetector computer tomography (MDCT) and magnetic resonance imaging (MRI) images.

CASE SUMMARY

We describe the case of a 34-year-old male, who underwent both MDC and MRI examinations of the upper abdomen because of liver cirrhosis. MDCT and MRI angiography images of the upper abdomen revealed an anatomic variation of the superior mesenteric vein (SMV), the double SMVs.

CONCLUSION

The double SMVs are a congenital abnormality without potential clinical manifestation. Physicians need to be aware of this anatomical variation during abdominal surgery to avoid iatrogenic injury.

Developing a phantom for simulating robotic-assisted complete mesocolic excision using 3D printing and medical imaging

BACKGROUND

Robotic-assisted complete mesocolic excision is an advanced procedure mainly because of the great variability in anatomy. Phantoms can be used for simulation-based training and assessment of competency when learning new surgical procedures. However, no phantoms for robotic complete mesocolic excision have previously been described. This study aimed to develop an anatomically true-to-life phantom, which can be used for training with a robotic system situated in the clinical setting and can be used for the assessment of surgical competency.

METHODS

Established pathology and surgical assessment tools for complete mesocolic excision and specimens were used for the phantom development. Each assessment item was translated into an engineering development task and evaluated for relevance. Anatomical realism was obtained by extracting relevant organs from preoperative patient scans and 3D printing casting moulds for each organ. Each element of the phantom was evaluated by two experienced complete mesocolic excision surgeons without influencing each other's answers and their feedback was used in an iterative process of prototype development and testing.

RESULTS

It was possible to integrate 35 out of 48 procedure-specific items from the surgical assessment tool and all elements from the pathological evaluation tool. By adding fluorophores to the mesocolic tissue, we developed an easy way to assess the integrity of the mesocolon using ultraviolet light. The phantom was built using silicone, is easy to store, and can be used in robotic systems designated for patient procedures as it does not contain animal-derived parts.

CONCLUSIONS

The newly developed phantom could be used for training and competency assessment for robotic-assisted complete mesocolic excision surgery in a simulated setting.

Novel approach toward minimally invasive surgery for mid-transverse colon cancer: 'moving the left colon' technique

AIM

During surgery for mid-transverse colon cancer (MTC), surgeons often face the dilemma of whether to mobilize the hepatic or splenic flexure. There is no established optimal minimally invasive surgical procedure for MTC.

METHODS

We present our novel minimally invasive surgical technique, called the 'moving the left colon' technique for MTC, along with a video demonstration. The procedure involves four main steps: (i) mobilization of the splenic flexure using a medial-to-lateral approach, (ii) dissection of lymph nodes around the middle colic artery from the left side of the superior mesenteric artery approach, (iii) separation of the pancreas and transverse mesocolon and (iv) 'moving the left colon' and performing an intracorporeal anastomosis. By mobilizing the splenic flexure, anatomical landmarks are revealed, which enables safer dissection. Combining this technique with intracorporeal anastomosis allows for a safe and easy anastomosis.

RESULTS

Between April 2021 and January 2023, a single-skilled colorectal surgeon performed laparoscopic transverse colectomies using our new approach on three consecutive patients with MTC. The patients had a median age of 75 years (range 46-89 years). The median operative time was 194 min (range 193-228 min) and blood loss was 8 mL (range 0-20 mL). None of the patients experienced any perioperative complications and the median postoperative hospital stay was 6 days.

CONCLUSION

We introduced a novel approach for laparoscopic surgery for MTC. This technique can be performed safely and may help standardize minimally invasive surgery for MTC.

First jejunal vein, jejunal trunk, and pancreatico-duodenectomy: resolving the literature conundrum

A detailed knowledge of the surgical anatomy of tributaries of the superior mesenteric vein, especially proximal jejunal venous anatomy (first jejunal vein and jejunal trunk), is a key prerequisite for performing a safe pancreatico-duodenectomy. However, the available literature on the anatomical course and surgical relevance of these vessels is scarce, the nomenclature across the articles is heterogeneous, and the resulting evidence is confusing to interpret. Standardized terminology and an in-depth review of these vessels with regard to their course, termination, vascular relations, and variations will help the surgeons in planning and performing this complex surgery safely, especially when a venous resection and reconstruction is planned in cases of borderline resectable pancreatic cancer. A uniform nomenclature and a unifying classification are proposed in this review for these two tributaries to help resolve the literature conundrum. This standardized terminology and anatomical description will assist the radiologists in reporting pancreatic protocol-computed tomography scans and surgeons in selecting the appropriate steps for the different anatomical orientations of these tributaries for the performance of safe pancreatic surgery. This will also help future researchers communicate in well-defined terms in reference to these tributaries so as to avoid confusion in future studies.

The usefulness of the endoscopic surgical skill qualification system in laparoscopic right hemicolectomy: a single-center, retrospective analysis with propensity score matching

PURPOSE

Recently, a new certification system called the Endoscopic Surgical Skill Qualification System (ESSQS) has been launched in Japan to improve surgical safety. This study aimed to determine whether ESSQS-qualified surgeons affect the short- and long-term outcomes of laparoscopic right hemicolectomy.

METHODS

A total of 187 colon cancer patients who underwent laparoscopic right hemicolectomy at Kindai University Hospital between January 2016 and December 2020 were enrolled. These patients were divided into two groups based on surgeries performed by ESSQS-qualified surgeons (QS group) and non-ESSQS-qualified surgeons (NQS group). The short- and long-term outcomes were compared between the two groups before and after propensity score matching (PSM).

RESULTS

After PSM, 43 patients from each group were included in the matched cohort. In the short-term outcomes, the total operative time was significantly longer in the NQS group than in the QS group (229 vs. 174 min, p < 0.0001). However, there were no significant differences in the two groups regarding blood loss (0 vs. 0 ml, p = 0.7126), conversion (0.0% vs. 7.0%, p = 0.0779), Clavien-Dindo ≥ 2 complications (9.3% vs. 7.0%, p = 0.6933), mortality (2.3% vs. 0.0%, p = 0.3145), and postoperative hospital stay (9 vs. 9 days, p = 0.5357). In the long-term outcomes, there were no significant differences between the two groups in the 3-year overall survival (86.6% vs. 83.0%, p = 0.8361) and recurrence-free survival (61.7% vs. 72.0%, p = 0.3394).

CONCLUSION

Laparoscopic right hemicolectomy performed by ESSQS-qualified surgeons contributed to shorter operative time. Under the supervision of ESSQS-qualified surgeons, almost equivalent safety and oncological outcomes are expected even in surgeries performed by non-ESSQS-qualified surgeons.

Frequencies and Injury Analysis of Small Anterior Branch of Gastrocolic Trunk

Objective: Small anterior branch of gastrocolic trunk (SABGT) can be occasionally observed during transverse colectomy and right hemicolectomy. Improperly dealing with the branch may lead to unwanted bleeding and affect the operation process. The purposes of this study are to analyze the frequencies and injury of SABGT. Methods: Intact operation data were collected retrospectively from 39 colon cancer patients who underwent curative laparoscopic transverse colectomy or right hemicolectomy. Frequencies and injury of SABGT were analyzed. Results: Eight cases had SABGT, the frequencies of which is 20.5%. Injury of SABGT occurred intraoperatively in 2 patients. Conclusion: We suggest that SABGT should be considered in surgical management. Consciously looking for and properly dealing with the branch can minimize the influence on the operation process.

Anatomic patterns and clinical significance of gastrocolic trunk of Henlé in laparoscopic right colectomy for colon cancer: Results of the HeLaRC trial

BACKGROUND

Recent interest in laparoscopic right colectomy with D3 lymphadenectomy for right colon cancer, has raised renewed attention to the anatomic variations of the gastrocolic trunk of Henlé (GTH). Understanding the vascular structure of the GTH region for individual patients should improve surgical outcomes. The goal of this nationwide multicenter study (Anatomical Classification of Henlé's Trunk in Laparoscopic Right Hemi-colectomy (HeLaRC) trial) was to study the anatomic patterns of the GTH region, to clarify the implications of GTH in laparoscopic right colectomy with D3 lymphadenectomy (D3-RC) and analyze their clinical significance.

METHODS

We enrolled 583 patients from 26 centers across China who underwent D3-RC. The number of tributaries, length and types of GTH constitutions and their influence on intra-operative data were investigated. A nomogram score (based on the length of GTH, body mass index (BMI), tumor location, T stage and type of GTH (type I vs. non-type I) was established to assess the potential hazard of bleeding.

RESULTS

The GTH was found in 567 patients (97.3%). The distribution of GTH types was 0 (14.1%, n = 80), I (53.3%, n = 302), II (27.0%, n = 153), III (5.6%, n = 32). Of note, the type I GTH, T1 stage and tumor location at ileocecal or ascending colon were correlated with shorter exposure time of the GTH region (P < 0.0001). Short length of GTH (P = 0.002) and tumor location (transverse colon vs. non transverse colon) (P = 0.003) were correlated with the amount of GTH bleeding during the surgery. Nomogram discrimination was good (C-index: 0.72 (95% CI: 0.64, 0.80)). The dissection plane was better in patients with type I GTH than with other types (P = 0.023).

CONCLUSION

GTH pattern variations may affect surgical outcomes in patients undergoing D3-RC. Better recognition of GTH anatomy might lead to a safer operation with better oncologic quality.

Efficacy of High-Resolution Preoperative 3D Reconstructions for Lesion Localization in Oncological Colorectal Surgery—First Pilot Study

When planning an operation, surgeons usually rely on traditional 2D imaging. Moreover, colon neoplastic lesions are not always easy to locate macroscopically, even during surgery. A 3D virtual model may allow surgeons to localize lesions with more precision and to better visualize the anatomy. In this study, we primary analyzed and discussed the clinical impact of using such 3D models in colorectal surgery. This is a monocentric prospective observational pilot study that includes 14 consecutive patients who presented colorectal lesions with indication for surgical therapy. A staging computed tomography (CT)/magnetic resonance imaging (MRI) scan and a colonoscopy were performed on each patient. The information gained from them was provided to obtain a 3D rendering. The 2D images were shown to the surgeon performing the operation, while the 3D reconstructions were shown to a second surgeon. Both of them had to locate the lesion and describe which procedure they would have performed; we then compared their answers with one another and with the intraoperative and histopathological findings. The lesion localizations based on the 3D models were accurate in 100% of cases, in contrast to conventional 2D CT scans, which could not detect the lesion in two patients (in these cases, lesion localization was based on colonoscopy). The 3D model reconstruction allowed an excellent concordance correlation between the estimated and the actual location of the lesion, allowing the surgeon to correctly plan the procedure with excellent results. Larger clinical studies are certainly required.

Anatomic variations of the anterosuperior pancreaticoduodenal veins encountered during laparoscopic right hemicolectomy: a retrospective single-center analysis

Objective

The vascular anatomic variations of the right colon present a challenge for colorectal surgeons. However, there have been few detailed studies of the variations in the anterosuperior pancreaticoduodenal vein (ASPDV).

Methods

We studied consecutive patients with right colon cancer who underwent laparoscopic right hemicolectomy at Peking University First Hospital (N = 117) between January 2018 and June 2021.

Results

The variations in the ASPDV were classified as type I (n = 101, (86.3%)), defined as ASPDVs draining into the gastrocolic trunk of Henle (GCT); type II (n = 10, (8.5%)), defined as ASPDVs draining into the superior mesenteric vein (SMV); or type III, defined as ASPDVs draining into both the GCT and SMV. For type I, subtypes were defined according to the branching of the ASPDVs: subtype a, with one branch (n = 87, (86.1%)); subtype b, with two branches (n = 12, (11.9%)); and subtype c, with more than two branches (n = 2, (2.0%)). Type I was also subtyped according to the confluence of the ASPDV and GCT, with subtype 1 being defined by a proximal site (n = 96, 95%) and subtype 2 by a distal site (n = 5, 5.0%).

Conclusions

We have characterized the variations in ASPDVs encountered during laparoscopic right hemicolectomy, which should provide a reference for colorectal surgeons.

Sequential Minimally Invasive Treatment of Concomitant Abdominal Aortic Aneurysm and Colorectal Cancer: A Single-Center Experience

BACKGROUND

The surgical management of concomitant occurrence of abdominal aortic aneurysm (AAA) and colorectal cancer (CRC) is still controversial. Conversely, benefits from a minimally invasive approach are well known concerning the treatment of both AAA and CRC. The aim of this study is to assess safety and feasibility of a sequential 2-staged minimally invasive during the same recovery by endovascular aneurysm repair (EVAR) technique and laparoscopic colorectal resection.

METHODS

From January 2008 to December 2020, all patients with concomitant AAA and CRC were consecutively treated by EVAR and laparoscopic colorectal resection. Perioperative data were retrospectively collected in order to evaluate short- and long-term outcomes following the sequential 2-staged procedures.

RESULTS

A total of 24 patients were included. The localization of the aneurysm was infrarenal abdominal aortic in 23 cases and in one case of common iliac artery. EVAR procedure has always been performed first. In 18 patients, a percutaneous access has been used while in 6 patients a surgical access has been adopted. Twelve patients had cancer in the left colon, 9 in the right colon, and 3 patients had rectal cancer. No conversions or intraoperative complications had occurred during laparoscopic surgery. The major complications rate after EVAR and CRC surgery was 8.3% and 12.5%, respectively. The mean interval between EVAR and CRC treatment was 7.8 ± 1 and the mean length of stay was 15.4 ± 3.6. No deaths occurred during hospitalization and between the procedures. Overall mortality was 20.8% with a mean follow-up of 39.41 ± 19.2 months.

CONCLUSION

Elective sequential 2-staged minimally invasive treatment is a safe and feasible approach with acceptable morbidity and mortality rates and it should be adopted in current clinical practice to manage concomitant AAA and CRC.

Initial retrocolic endoscopic tunnel approach: A promising technique for radical right hemicolectomy

Background:

Complete mesocolic excision with central vascular ligation for colonic cancers improves overall survival. To achieve better short term and oncological results, different laparoscopic techniques have been described for right-sided colonic cancers. Laparoscopic right hemicolectomy by the Initial Retrocolic Endoscopic Tunnel Approach (IRETA) is proposed to be easy and offer desired oncological resection; we present our results with IRETA.

Patients and Methods:

The data of all patients who underwent right hemicolectomy by IRETA for colonic cancer between January 2019 and March 2020 were retrospectively analysed for demographics, clinical features, oncological completeness of resected specimen, complications, hospital stay, morbidity and mortality.

Results:

A total of eight patients (05 males and 03 females) were identified. The mean operating time was 190 ± 32.40 minutes. Margins of all resected specimens were free of tumour except for one in which retro-peritoneal circumferential resection margin was positive. On average 13.75 ± 2.63 lymph nodes were retrieved. Except for wound infection in one patient, no other morbidity was seen.

Conclusion:

Laparoscopic radical right hemicolectomy by IRETA is safe and gives desired oncological results.

Management of intraoperative complications during laparoscopic right colectomy

BACKGROUND

Minimally invasive right colectomy is increasingly performed as standard treatment for diseases of right colon. Complete mesocolic excision has been introduced for cancer treatment to improve oncological results. Both standard and complete mesocolic excision techniques are associated with intraoperative complications. The purpose of this study was to analyse incidence and management of intraoperative complications in patients who underwent laparoscopic right colectomy with complete mesocolic excision in a single institution.

METHODS

This is a retrospective study conducted in a single Italian centre from April 2017 to October 2020. Data of non-metastatic cancer patients who underwent laparoscopic right colectomy were collected to analyse onset of intraoperative complications, their management and rate of conversion to open surgery.

RESULTS

A total of 92 patients were included in this study. The 1.09% of patients were converted to open surgery due to adhesions and bowel occlusion. The 5.43% of patients had intraoperative complications: bleeding from Henle's trunk, pre-pancreatic plane and ileocolic artery stump account for 3.26%, gonadal vessel injury for 1.09% and bowel lesion for 1.09%.

CONCLUSIONS

Despite the limits of this study, it shows that bleeding is one of the most frequent complications in laparoscopic right colectomy. Bleeding, occlusion and adhesions are most common reasons for conversion to open surgery.

Computed Tomography Angiography of Gastrocolic Vein Trunk by Morphological Filtering Technique in Right Colon Cancer

Background

This study was to evaluate CT vein image segmentation and three-dimensional imaging in the anatomical structure of gastrocolic venous trunk before operation for colon cancer.

Methods

CT scanning images by Philips Brilliance CT 256CT scanner. Vein position was segmented and calculated by grey value through algorithm flow. Intensity measurement of selected image area by a calculate through noise cancellation and missing pixel filling, based on numerical morphology.

Results

The direction of the right colonic vein could be clearly displayed in all 96 patients by morphological filtering technique. Among these patients, there were 78 patients with gastrocolic vein trunk, with an occurrence rate of 81.25%. According to the classification of GVT, there were 36 cases of type A (46.2%), 22 cases of type B (28.2%), 12 cases of type C (15.4%) and 6 cases of type D (7.7%).

Conclusion

CT vein image segmentation and three-dimensional imaging can effectively evaluate the anatomical variation of gastrocolic vein trunk before operation, which is helpful for operators to correctly understand its anatomical structure and choose a reasonable anatomical approach.

Current status and trend of laparoscopic right hemicolectomy for colon cancer

Laparoscopic right hemicolectomy (LRH) is utilized worldwide as one of the standard surgical treatments for right-sided colon cancer. However, there have been issues concerning its applicability, techniques, and trend. The present study aimed to elucidate the current status and trend of LRH by reviewing literature focusing on important issues associated with this surgery. Based on previous studies, LRH most likely provides better short-term outcomes and similar oncological outcomes compared to open surgery. Despite the increasing use of robotic approach in this surgery, it seems to have always been associated with longer operative times and greater hospital cost with limited advantage. Intracorporeal anastomosis seems to improve short-term outcomes, such as quicker recovery of bowel function, compared to extracorporeal anastomosis. However, it does not contribute to shorter hospital stay. With regard to dissection technique, various approaches, and landmarks have been advocated to overcome the technical difficulty in LRH. This difficulty is likely to be caused by anatomical variation, especially in venous structures. The superiority of one approach or landmark over another is still argued about due to the lack of large-scale prospective studies. However, deep understanding both of anatomical variation and characteristics of each approach would be of extreme importance to minimize adverse effects and maximize patient benefit after LRH.

3D Printing Technology Improves Medical Interns' Understanding of Anatomy of Gastrocolic Trunk

OBJECTIVE

Complex vascular anatomy has always been a difficult point for medical students. Gastrocolic trunk (Henle trunk) has many branches and variations, involving the venous reflux of the stomach, right colon, and pancreas. This study investigated the effects of 3 dimensional (3D) printing technology on medical interns' understanding of Henle trunk's variation, by comparing 2 dimensional (2D) images.

SETTING

Henle trunk modes were manufactured using 3D-CT angiography and 3D-printing technology.

PARTICIPANTS

Forty-seven interns from 2 medical schools (Nanjing Medical University and Medical College of Nantong University) participated in the study.

DESIGN

The interns were divided randomly allocated into 2 groups, where group 1 was the control group with a 2D image of Henle trunk plus surgical video (named 2D image group), and group 2 was the study group with a 3D printed model of Henle trunk plus surgical video (named 3D-printing group). Knowledge of interns on the Henle trunk was compared between 2 groups using a question test before and after the teaching intervention.

RESULTS

All interns had an improved overall assessment score as a result of attending the seminar, whether in the 2D image group or the 3D-printing group. The score of the 2D image group increased 32.57 ± 13.86, and the 3D-printing group increased 47.04 ± 12.99, showing significant difference (p = 0.001). There was no significant difference observed between postseminar scores between 2 medical schools (p = 0.975). There was a significant improvement in satisfaction among the 3D-printing group for education depth, novel and inspiring of teaching method, except for the interaction between teacher and interns (p = 0.215). Interns hope to have more teaching time for 3D printing, and not satisfied with the time of 3D printing teaching compared with those in the 2D image group (p = 0.021).

CONCLUSIONS

The 3-D printed Henle trunk model is a very effective teaching tool, which can help interns understand the anatomy of Henle trunk. The application of 3D printing technology in the teaching of interns of complex vascular anatomy is worth popularizing in teaching hospitals.

How to do a complete mesocolic excision and central vascular ligation

We describe an approach for complete mesocolic excision and central vessel ligation utilizing a robotic platform. We describe the steps in detail focusing on a superior mesenteric vein-first approach.