Infrapyloric Artery Research Articles

Variations in the origin of the infrapyloric artery: A systematic review and meta-analysis

BackgroundThe infrapyloric artery (IPA) supplies the pylorus and the large curvature of the antrum. Its common origin points include the gastroduodenal artery (GDA) and right gastroepiploic artery (RGEA). The prevalence of variations in IPA origins can be of interest to gastric cancer surgeons who wish to increase their understanding of this vessel. The primary aim of this study was to perform a systematic review and meta-analysis on the origin of the IPA. The secondary aims were to assess imaging identification accuracy, to identify IPA morphological features, and to explore the relationship of IPA origin and clinicopathological characteristics. MethodsElectronic databases, currently registered studies, conference proceedings and the reference lists of included studies were searched through March 2023. There were no constraints based on language, publication status, or patient demographics. Database search, data extraction and risk of bias assessment were performed independently by two reviewers. The point of origin of the IPA was the primary outcome. Secondary outcomes were imaging identification accuracy, relationship between IPA origin and clinicopathological characteristics, and IPA morphological features. A random-effects meta-analysis of the prevalence of different IPA origins was conducted. Secondary outcomes were narratively synthesized given the heterogeneity of studies reporting on these. ResultsA total of 7279 records were screened in the initial search. Seven studies were included in the meta-analysis, assessing 998 patients. The IPA arose most frequently from the anterior superior pancreaticoduodenal artery (ASPDA), with a pooled prevalence of 40.4% (95% CI 17.1–55.8%), followed by the RGEA with a pooled prevalence of 27.6% (95% CI 8.7–43.7%), and the GDA with a pooled prevalence of 23.7% (95% CI 6.4–39.7%). Cases of multiple IPAs had a pooled prevalence of 4.9% (95% CI 0–14.3%). The IPA was absent in 2.6% (95% CI 0–10.3%) of cases and arose from the posterior superior pancreaticoduodenal artery (PSPDA) in the remaining 0.8% (95% CI 0 – 6.1%). Distance between the pylorus and the proximal branch of the IPA and distance from the pylorus to the first gastric branch of the RGEA when the IPA originated from the ASPDA and RGEA were longer than when the IPA originated from the GDA. The IPA is a small vessel (<1 mm), and its origin is not related to clinicopathological characteristics including patient sex, age, and tumor stage and location. ConclusionsSurgeons must be aware of the most common origin points of the IPA. Recommendations for future study include the stratification of IPA origin according to demographic characteristics, and further investigation into IPA morphological parameters such as tortuosity, course and relation to adjacent lymph nodes, aiding the creation of a standardized classification system pertaining to the anatomy of this vessel.

Comprehensive evaluation of three-dimensional anatomy of perigastric vessels using enhanced multidetector-row computed tomography

BackgroundTo perform laparoscopic gastrectomy safely, we aimed to comprehensively re-evaluate perigastric vessel anatomies using a three-dimensional angiography reconstructed from enhanced multidetector-row computed tomography data.MethodsPerigastric vessel anatomy was preoperatively analyzed using a multidetector-row computed tomography-based three-dimensional angiography reconstructed in 127 patients undergoing gastric surgery.ResultsOf the 67 left gastric veins that ran along the dorsal side of the arteries, 59 (88.1%) ran along the dorsal side of the common hepatic artery and flowed into the portal vein. In 18 cases, a common trunk of one to three left gastric arteries and the replaced left hepatic artery was observed. The left inferior phrenic artery ramified from the left gastric artery in 5.5% of the cases. The right gastric artery was classified into distal (73.2%), caudal (18.1%), and proximal (8.7%) types. The infra-pyloric artery was also classified into distal (64.6%), caudal (26.0%), and proximal (9.4%) types. The posterior gastric artery branched as a common trunk with the superior polar artery in the proximal (37.9%) and distal (18.4%) regions of the splenic artery. The left gastroepiploic artery ramified from the splenic (18.1%) and inferior terminal arteries (81.9%). No, one, and two gastric branches of the left gastroepiploic artery, which ramified between the roots of the left gastroepiploic artery and its omental branch, were found in 36.5%, 49.2%, and 14.3% of the cases, respectively.ConclusionsPreoperative 3D angiography is useful for the precise evaluation of perigastric vessel anatomies, and may help us to perform laparoscopic gastrectomy and robotic surgery safely.

Utility of virtual three-dimensional image analysis for laparoscopic gastrectomy conducted by trainee surgeons.

Purpose The aim of this study was to investigate the utility the three-dimensional (3D) imaging for laparoscopic gastrectomy performed by trainee surgeons. Methods 3D-reconstruction was performed using multi-detector computed tomography (MDCT) and SYNAPSE VINCENT software. Trainee surgeons made 3D-imaging and checked the anatomical structure. Thirty-three patients who underwent laparoscopic gastrectomy (LG) for gastric cancer were examined. Trainees performed 19 LG, while specialists performed 14 LG. The vascular pattern and the surgical outcomes were evaluated. Result 3D imaging depicted the correct positional relationship between the gastric vasculatures and the organs. Regarding vascular pattern detected by 3D imaging, the origins of the infrapyloric artery were the right gastroepiploic artery in 12 cases (36%), the gastroduodenal artery in eight cases (24%), the bifurcation of the right gastroepiploic artery and gastroduodenal artery in seven cases (21%), and not detected in one case (3%). The types of confluence of the infrapyloric vein were the right gastroepiploic vein in 16 cases (48%), the anterior superior pancreatoduodenal vein in 10 cases (30%), and not detected in seven cases (21%). Surgical outcomes were not different between trainee group using intraoperative 3D image with the specialist in instruction group without the intraoperative 3D image. Conclusions Preoperative 3D imaging might contribute to successful and safe LG by trainee surgeons. J. Med. Invest. 66 : 280-284, August, 2019.

Outermost layer-oriented medial approach for infrapyloric nodal dissection in laparoscopic distal gastrectomy.

Based on our experience of suprapancreatic nodal dissection in laparoscopic gastrectomy, we developed an outermost layer-oriented medial approach for infrapyloric nodal dissection. The objective of this single-institution retrospective study was to determine the feasibility, safety, and reproducibility of this novel and unique dissection procedure. This approach can be performed in the same manner as suprapancreatic nodal dissection but by replacing the left gastric artery with the right gastroepiploic artery (RGEA), the common hepatic artery with the anterior superior pancreaticoduodenal artery (ASPDA), and the splenic artery with the gastroduodenal artery. It comprises five steps: (1) mobilization of the transverse mesocolon along the prepancreatic membrane, (2) medial dissection along the dissectable layer between the pancreatic head and the dorsal side of the right gastroepiploic vein (RGEV), (3) division of the RGEV and determination of the lateral and cranial borders, (4) dissection along the outermost layer of the RGEA and ASPDA and transection of the infrapyloric artery and RGEA, and (5) transection of the duodenal bulb. This novel method was applied in 112 patients who underwent laparoscopic distal gastrectomy from 2014 to 2015. The anatomical landmarks that we determined to appropriately identify the outermost layer were highly reproducible, and our novel procedure based on these landmarks was successfully completed in all cases, without any intraoperative complications. Furthermore, in all cases, no. 6 lymph nodes were fully and adequately dissected within the infrapyloric area anatomically defined in the Japanese Classification of Gastric Carcinoma ver. 14. Pancreatic fistula occurred only in 1.8% cases. This novel outermost layer-oriented medial approach is a robust procedure that may help laparoscopic surgeons in performing safe and reproducible infrapyloric nodal dissection.

Anatomical variation of infra-pyloric artery origination: A prospective multicenter observational study (IPA-Origin).

ObjectiveInfra-pyloric artery (IPA) is an important anatomical landmark in treatment of gastric cancer and is the key vessel for pylorus-preserving gastrectomy and subgroup of infra-pyloric lymph nodes. However, its anatomical variation is not thoroughly understood. Our study aimed to clarify the origination of the IPA.MethodsWe did this prospective, multicenter, open-label, observational study at gastric surgery departments of 34 hospitals in China. Gastric cancer patients aged 18 years or older and scheduled to undergo elective total or distal gastrectomy were assigned. During the surgery, IPA dissecting and exposing the origination point with photographs or video clips were required. The primary outcome was the origination of the IPA. Analysis of variance, χ2 tests and Fisher’s tests were used to analyze the differences between groups. The study is registered at Clinicaltrials.gov (No. NCT03071237). ResultsBetween May 8 and July 31, 2017, 429 patients were assigned for the study, and 419 (97.7%) patients had the IPA dissected and recorded through photograph or video and were included in the primary outcome analysis. The median age was 62 years old, and 73.7% were male. Among the patients, 78.5% received laparoscopic surgery. Single IPA origination was identified in 398 (95.0%) patients, including gastroduodenal artery (GDA) in 154 (36.8%) patients, anterior superior pancreaticoduodenal artery (ASPDA) in 130 (31.0%) patients, and right gastroepiploic artery (RGEA) in 114 (27.2%) patients. Fifteen (3.6%) patients were identified with multiple IPA and 6 (1.4%) patients were identified as IPA absence. The differences in the distribution of surgical approach (P=0.003) and geographic area (P=0.030) were statistically significant. No difference was shown in sex, age, gastrectomy type, tumor location, and clinical T, N and M stage.ConclusionsOur study found that the IPA originates from GDA, ASPDA and RGEA in similar proportions. Laparoscopic surgery may be more helpful in dissection of the IPA than open surgery.

Real-time Vessel Navigation Using Indocyanine Green Fluorescence during Robotic or Laparoscopic Gastrectomy for Gastric Cancer.

PurposeIdentification of the infrapyloric artery (IPA) type is a key component of pylorus-preserving gastrectomy. As the indocyanine green (ICG) fluorescence technique is known to help visualize blood vessels and flow during reconstruction, we speculated that this emerging technique would be helpful in identifying the IPA type.Materials and MethodsFrom August 2015 to February 2016, 20 patients who underwent robotic or laparoscopic gastrectomy were prospectively enrolled. After intravenous injection of approximately 3 mL of ICG (2.5 mg/mL), a near-infrared fluorescence apparatus was applied. The identified shape of the IPA was confirmed by examining the actual anatomy following infrapyloric dissection.ResultsThe mean interval time between ICG injection and visualization of the artery was 22.2 seconds (range, 14–30 seconds), and the mean duration of the arterial phase was 16.1 seconds (range, 9–30 seconds). The overall positive predictive value (PPV) of ICG fluorescence in identifying the IPA type was 80% (16/20). The IPA type was incorrectly predicted in four patients, all of whom were obese with a body mass index (BMI) of more than 25 kg/m2.ConclusionsOur preliminary results indicate that intraoperative vascular imaging using the ICG fluorescence technique may be helpful for robotic or laparoscopic pylorus-preserving gastrectomy.

Lymphadenectomy along the infrapyloric artery may be dispensable when performing pylorus-preserving gastrectomy for early middle-third gastric cancer.

This study investigated the incidence of gastric cancer metastasis to the lymph nodes along the infrapyloric artery (IPA), namely no. 6i, by reviewing our medical records of 348 patients who underwent complete no. 6 dissection. Metastasis to these nodes was observed in 11 (3.2%) patients. In these patients, one huge tumor was located in the middle third and ten including two early tumors were located in the lower third; the metastasis rate in early lower-third tumors was 2.1% and reached 19.5% in advanced tumors. In contrast, no early middle-third gastric cancers had no. 6i metastasis. The median diameter of 6i-positive tumors was 62 (range 18-115)mm, and the distance from the distal tumor border to the pyloric ring was no more than 44mm. Lymphadenectomy along the IPA is important for treating gastric cancer invading the antrum, but may be dispensable when performing pylorus-preserving gastrectomy for early middle-third cancer.

Anatomical considerations of the infrapyloric artery and its associated lymph nodes during laparoscopic gastric cancer surgery.

Little is known about the vascular and lymphatic distribution of the pyloric antrum in the stomach. We focused on the infrapyloric region containing the infrapyloric artery (IPA) and lymph nodes. The anatomy of the IPA and its associated lymph nodes was clinically elucidated during 156 laparoscopic gastrectomies. Most of the arteries originated from the anterior superior pancreatoduodenal artery (ASPDA, 64.2 %) or the root of the right gastroepiploic artery (RGEA, 23.1 %), but a small portion originated from the gastroduodenal artery (GDA, 12.7 %). The average lengths from the pyloric ring to the IPA proximal branch were 21.8 mm from the ASPDA, 20.6 mm from the RGEA and 9.0 mm from the GDA, a significantly shorter length than the other 2 variations. On average, 2.5 out of 10.0 nodes existed along the IPA. One patient, whose tumor was located close to the pylorus, had a metastatic node in this section. The IPA most commonly originates from the ASPDA and is associated with a certain number of lymph nodes. Vascular distribution from the IPA depends on the anatomic variation.

Anatomical basis of antropyloric transposition for fecal incontinence in humans: the infrapyloric approach

Antropylorus transposition in the perineum for end-stage anal incontinence has shown to be feasible in humans. Vascular anatomy of the antro-pyloro-duodenal area is critical in preventing complications and increasing pyloric graft survival. This study was undertaken to examine the vascular anatomy of antro-pyloro-duodenal area in an attempt to safeguard the graft blood supply and improve its survival. After obtaining preoperative CT angiography to delineate the infrapyloric artery (IP a.), bench dissection of resected pancreaticoduodenectomy specimens was performed in 12 patients. Ex vivo angiography of these specimens were also performed. Subsequent to the information obtained from these dissections, the method of antropylorus mobilization during transposition was modified in terms of the site of division of the right gastroepiploic a. (Rt GEA). Perioperative outcomes (graft related complications, fecal incontinence scores, Doppler flow studies, and manometry studies of the graft) were compared between the two groups. IP a. originated only from the Rt GEA in 8 cases (66%) and from both the gastroduodenal a. and the Rt GEA in the rest. However, its origin solely from the gastroduodenal a. was not observed. The pyloric graft survival, pyloric valve pressures and Doppler flow velocities were significantly (p<0.05) better when the infrapyloric a. was preserved following this refinement. However, no immediate significant difference in incontinence scores was observed. Careful preservation of the pyloric valve vascularity by preserving the IP a. by dividing the Rt GEA at its origin increases vascularity, survival and contractility of the pyloric graft in perineum.

Current Status of Pylorus‐Preserving Gastrectomy for the Treatment of Gastric Cancer: A Questionnaire Survey and Review of Literatures

This study was designed to investigate the current status of pylorus-preserving gastrectomy (PPG) for the treatment of gastric cancer by sending a questionnaire to institutions in Japan. The questionnaire was prepared and sent to 930 institutions approved by the Japanese Society of Gastroenterological Surgery. Questions were the indications for PPG, preservation of the vagus nerves and the infra-pyloric artery, whether suprapyloric lymph nodes are dissected, distance between the pylorus and the gastrogastrostomy, and the advantages and disadvantages of PPG. Responses were obtained from 345 institutions (37.1%). In 148 institutions, PPG was included in the choices of operations for gastric cancer and indicated for patients with tumors no deeper than the submucosal layer for differentiated-type carcinoma, or for tumors limited to the mucosa even in poorly differentiated types in 105 institutions. The vagus was preserved in 73.5%, the infrapyloric artery was preserved in 49.4%, and the dissection of suprapyloric lymph nodes were partly performed in 56.2%. The distance between gastrogastrostomy and the pyloric ring was 3-3.9cm in 43.4% and 2-2.9cm in 39%. Layer-to-layer anastomosis was the most representative technique for gastrogastrostomy. The advantages of PPG with decreased incidence of dumping syndrome and remnant gastritis were quoted in 130 and 82 institutions, respectively. Delayed gastric emptying was considered as the most frequent disadvantage of PPG, as quoted by 111 institutions. These results indicate that standard technique in PPG includes the preservation of the vagus and infrapyloric artery, in part dissection of suprapyloric lymph nodes, and layer-to-layer anastomosis for reconstruction. The optimal length of the antral cuff is still controversial.

Surgical anatomy of the innervation of pylorus in human and Suncus murinus, in relation to surgical technique for pylorus-preserving pancreaticoduodenectomy

To clarify the innervation of the antro-pyloric region in humans from a clinico-anatomical perspective. The stomach, duodenum and surrounding structures were dissected in 10 cadavers, and immersed in a 10mg/L solution of alizarin red S in ethanol to stain the peripheral nerves. The distribution details were studied to confirm innervations in the above areas using a binocular microscope. Similarly, innervations in 10 Suncus murinus were examined using the method of whole-mount immunohistochemistry. The innervation of the pyloric region in humans involved three routes: One arose from the anterior hepatic plexus via the route of the suprapyloric/supraduodenal branch of the right gastric artery; the second arose from the anterior and posterior gastric divisions, and the third originated from the posterior-lower region of the pyloric region, which passed via the infrapyloric artery or retroduodenal branches and was related to the gastroduodenal artery and right gastroepiploic artery. For Suncus murinus, results similar to those in humans were observed. There are three routes of innervation of the pyloric region in humans, wherein the route of the right gastric artery is most important for preserving pyloric region innervation. Function will be preserved by more than 80% by preserving the artery in pylorus-preserving pancreaticoduodenectomy (PPPD). However, the route of the infrapyloric artery should not be disregarded. This route is related to several arteries (the right gastroepiploic and gastroduodenal arteries), and the preserving of these arteries is advantageous for preserving pyloric innervation in PPPD. Concurrently, the nerves of Latarjet also play an important role in maintaining innervation of the antro-pyloric region in PPPD. This is why pyloric function is not damaged in some patients when the right gastric artery is dissected or damaged in PPPD.

Pylorus-preserving gastrectomy in gastric cancer surgery—open and laparoscopic approaches

Pylorus-preserving gastrectomy (PPG) has been accepted as a function-preserving procedure for early gastric cancer for the prevention of postgastrectomy syndrome. In general, PPG procedures have not included suprapyloric lymph node dissection to preserve the pyloric branch of the vagal nerve and the right gastric artery. The aim of this article is to describe procedures for PPG. The technique of laparoscopy-assisted pylorus-preserving gastrectomy (LAPPG) is also introduced because PPG is an ideal application for laparoscopic surgery. Between September 2000 and September 2004, we performed 37 cases of conventional PPG and further 73 cases of LAPPG. In these patients, PPG including complete lymph node dissection around the remnant pyloric cuff was performed. For this purpose, it is recommended that the blood flow to the pyloric cuff be maintained by preserving the infrapyloric artery. All the patients showed good postoperative recovery, and no intraoperative or postoperative major complications were observed. No sign of recurrence was found in these 110 patients, and none of them demonstrated dumping syndrome. The procedures of both PPG and LAPPG are technically feasible and have an important role in the surgical management of early gastric cancer in terms of better quality of postoperative life, even with lymphadenectomy including combined suprapyloric lymph node dissection and right gastric artery division.

Feasibility of pylorus-preserving gastrectomy with a wider scope of lymphadenectomy.

To demonstrate the feasibility and safety of pylorus-preserving gastrectomy (PPG) accompanied by complete suprapyloric and infrapyloric lymph node dissection. Retrospective review. A university hospital in Japan. Fifteen patients underwent PPG, and 28 patients underwent conventional distal gastrectomy (CDG) with Billroth I anastomosis. All patients had early gastric cancer, with either limited invasion in the mucosal layer or invasion into the submucosal layer. In the PPG procedure, the distal part of the stomach was resected while retaining a 1.5-cm pyloric cuff. The right gastroepiploic artery, the right gastric artery, and hepatic and pyloric branches of the vagus nerve were divided, and the infrapyloric artery was preserved. A modified D1 or D2 lymphadenectomy accompanied the PPG. Patients undergoing the PPG and CDG procedures were assessed 1 year after their surgical procedure. Changes in body weight, serum total protein levels, and serum albumin levels, the incidence of dumping syndromes, and endoscopic findings in the gastric remnant were compared between the 2 groups. Weight loss was significantly less in the PPG group than in the CDG group (P=.02). The incidences of early dumping syndromes, especially vasomotor symptoms, were significantly lower in the PPG group than in the CDG group (P=.03 and P=.02, respectively). The pyloric sphincter function was preserved, and there was no anastomotic leakage in the PPG group. The PPG procedure with complete D2 lymphadenectomy can be performed safely with a low incidence of major complications and a better postoperative outcome than the CDG procedure. The PPG procedure can be recommended for the treatment of early gastric cancer with broader indications.

Pylorus-preserving gastrectomy with radical lymph node dissection based on anatomical variations of the infrapyloric artery

We devised a method for performing pylorus-preserving gastrectomy (PPG) with radical lymph node dissection without compromising pyloric blood flow, based on vascular anatomical evaluation of 210 celiac angiograms. The origin of the infrapyloric artery was variable, but consistently supplied blood flow to the pylorus and the posterior wall of the antrum. When the infrapyloric artery originated from the gastroduodenal artery or from one of its pancreatic branches (type A, 88%), the right gastroepiploic artery was divided at its origin, allowing the excision of all adjacent lymph nodes. When the infrapyloric artery originated from the right gastroepiploic artery (type B, 12%), the right gastroepiploic artery was divided distal to the infrapyloric artery origin and the short right gastroepiploic artery remnant was skeletonized of lymph nodes. We have used this technique to perform PPG on 25 patients with early gastric cancer in the middle third of the stomach with minimal morbidity and no mortality.

The infrapyloric artery and cephalic pancreatoduodenectomy with pylorus preservation: preliminary study.

Cephalic pancreatoduodenectomy (CPD) with pylorus preservation has been suggested to improve the functional and nutritional result of surgery. At operation, the first two centimeters of the duodenum are preserved, the vascular arch of the lesser gastric curvature is saved and the right gastroepiploic artery is resected at its origin. The aim of this study on 15 fresh cadavers was to determine the origin of the vascularization of the remaining duodenum and also the possibilities of preserving an optimal vascularization after CPD and pylorus preservation. All of the arteries supplying the remaining duodenum and arising either from the right gastric artery or the right gastroepiploic artery were identified. The distances between the origin of the infrapyloric artery and the termination of the gastroduodenal artery on the cranial and ventral pancreaticoduodenal artery and the left gastroepiploic artery were measured. At CPD with pylorus preservation, the study demonstrated that: 1) the cranial side of the remaining duodenum remains vascularized in 80% of the cases by one or two supraduodenal branches coming from the right gastric artery; 2) ligation of the right gastroepiploic artery eliminates all vascular supply to the caudal side of the remaining duodenum in almost half of the cases; 3) in these cases, the dissection of the bifurcation of the gastroduodenal artery and the vascular section beyond the origin of the infrapyloric artery allowed a direct vascular supply to the remaining duodenum to be preserved.