Preventive effect on delayed gastric emptying of preserving the infra-pyloric vein in laparoscopic pylorus-preserving gastrectomy for early gastric cancer.

BACKGROUND: Pylorus-preserving gastrectomy (PPG) has the postoperative advantages of a better quality of life and less weight loss than distal gastrectomy. However, postoperative delayed gastric emptying (DGE) due to antral hypomotility can be a problem. Although preserving the infra-pyloric vein (IPV) is reported to improve congestion of the antrum and prevent DGE, the benefits of this procedure have not been confirmed. The present study aimed to clarify the preventive effect on DGE of preserving the IPV. METHODS: A total of 148 patients [IPV-preserved (IPVP): 78 patients and IPV-non-preserved (IPVN): 70 patients] who underwent laparoscopic and robotic PPG (LRPPG) for early gastric cancer were enrolled in this study. The clinicopathologic characteristics and incidence of DGE were compared between the groups. The nutritional risk index (NRI) at 1, 2, and 3 years after the operation and the relapse-free survival (RFS) were also compared. RESULTS: There were no significant differences in the clinicopathological characteristics between the two groups. DGE was observed in 15 of 148 patients (10.1%). The incidence of DGE did not differ markedly between the 2 groups (IPVP vs. IPVN; 11.5% vs. 8.6% p = 0.596). There were no significant differences in other complications between the groups either (IPVP vs. IPVN; 19.2% vs. 21.4%; p = 0.838). The NRI and 3-year RFS were not significantly different between the two groups. CONCLUSION: Regarding LRPPG, preserving the IPV did not help prevent DGE and resulted in no significant difference in the outcomes.

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 44 mm. 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.

Preserving infrapyloric vein reduces postoperative gastric stasis after laparoscopic pylorus-preserving gastrectomy.

PURPOSE: Laparoscopic pylorus-preserving gastrectomy (LPPG) is performed to preserve function in treating early gastric cancer. However, gastric stasis is a potential complication of LPPG that could decrease postoperative quality of life, possibly due to gastric edema of the pyloric cuff caused by venous stasis. We introduced an infrapyloric vein (IPV)-preserving LPPG (iLPPG) procedure to prevent pyloric cuff edema and thus minimize the incidence of gastric stasis and investigated the early clinical outcomes of iLPPG. METHODS: We reviewed 150 patients with gastric cancer who underwent LPPG between August 2011 and June 2013 at the Cancer Institute Hospital and analyzed postoperative complications, incidence of gastric stasis (requiring starvation longer than 72 h or an invasive treatment), and transient delayed gastric emptying (TDGE). RESULTS: Of the 150 patients, 56 underwent iLPPG and 94 underwent conventional LPPG without preservation of the IPV (cLPPG). Morbidity rates were 5.4% in the iLPPG group and 23.4% in the cLPPG group (P = 0.003). The incidence of both gastric stasis and TDGE was significantly lower in the iLPPG group than in the cLPPG group (0 vs. 8.5%, P = 0.03 and 0 vs. 7.4%, P = 0.046, respectively). Median postoperative stay was significantly shorter in the iLPPG group compared to the cLPPG group (9 vs. 11 days, P < 0.001, respectively). CONCLUSIONS: Preservation of the IPV might prevent the incidence of postoperative gastric stasis after LPPG, resulting in a shorter postoperative stay.

Anatomical Knowledge for the Infra-Pyloric Vein Preservation during the Laparoscopy-Assisted Pylorus-Preserving Gastrectomy.

BACKGROUND: Fine anatomical knowledge enables us to use safer laparoscopy-assisted pylorus-preserving gastrectomy (LAPPG). Detailed anatomical knowledge of the infra-pyloric vein (IPV) remains obscure. In this study, the aim was to classify the IPV vessel flow. METHODS: From April 2009 to November 2012, 43 patients with clinical T1 gastric cancer underwent LAPPG with preservation of IPV. Operative videos were retrospectively reviewed, and an anatomical classification of IPV was proposed. RESULTS: The IPV flow came into the right gastro-epiploic vein (RGEV) and/or the anterior superior pancreaticoduodenal vein (ASPDV). The IPV anatomical flow pattern was classified according to the following 4 types: Type I, the IPV more than 2 flow into RGEV; Type IIa, only 1 IPV into RGEV without into ASPDV; Type IIb, one IPV flow into RGEV and one flow into ASPDV; Type III, IPV only into ASPDV. The proportion of each type was 39.5% (17/43) in Type I, 30.2% (13/43) in Type IIa, 14% (6/43) in Type IIb, and 16.3% (7/43) in Type III. CONCLUSIONS: The anatomical flow pattern of the IPV was described. It would be beneficial to improve the anatomical knowledge of the IPV for more elaborate and safer lymph node dissection during laparoscopic gastrectomy.

Free Antropyloric Valve Flap for End-Stage Fecal Incontinence as a Substitute to Permanent Colostomy.

BACKGROUND: Surgical removal of the anal canal and sphincter for carcinoma results in end-stage fecal incontinence (ESFI) and requires a permanent colostomy resulting in significant impact on quality of life. Presently, there are limited options for EFSI. The successful use of pedicled antropyloric valve (APV) based on left gastroepiploic artery as an alternative to permanent colostomy has previously been described. It is based on a long omental pedicle which at times is risky and is difficult to perform. A free APV flap could be the only solution in such cases. We assessed the vascular anatomy for the technical feasibility of a free APV flap, and report the first ever clinical application of free APV flap. METHODS: Bench dissection of 10 pancreaticoduodenectomy specimens was done to delineate the vessels of APV flap. It showed the consistent presence of right gastroepiploic and infrapyloric vessels in all specimens with sufficient diameters. After the technical feasibility, a free APV Flap transposition to perineum was done in a patient, where pedicled transposition was not feasible. RESULTS: The free APV flap with vagus nerve branch was harvested without extensive dissection along the greater curvature of stomach. A tension free anastomosis was achieved between the epiploic and left colic vessels. The flap survived well and had a definite tone on digital examination. It was evaluated by radiological and manometric methods. CONCLUSIONS: APV flap for EFSI can be done as a free flap with distinct advantages and it has the potential of becoming popular options for EFSI.

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

BACKGROUND: 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. METHODS: The anatomy of the IPA and its associated lymph nodes was clinically elucidated during 156 laparoscopic gastrectomies. RESULTS: 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. CONCLUSION: 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.

Neurovascular antropylorus perineal transposition using inferior rectal nerve anastomosis for total anorectal reconstruction: preliminary report in humans.

BACKGROUND: Technical feasibility of inferior rectal nerve anastomosis to the anterior vagus branch of the perineally transposed antropyloric valve for total anorectal reconstruction has been previously demonstrated in cadavers. To the best of our knowledge, the present study is the first report of using this procedure in humans. METHODS: Eight patients [mean age 35.5 years (range 15-55 years); (male/female = 7:1)] underwent the procedure. The antropyloric valve with its anterior vagus branch was mobilized based on the left gastroepiploic arterial pedicle. The antral end was anastomosed to the distal colon. The anterior vagus nerve was anastomosed by epineural technique to the inferior rectal nerve in the perineum. A diverting proximal colostomy was maintained for 6 months. Anatomical integrity of the graft (on magnetic resonance imaging scans), its arterial pedicle (on computed tomography angiogram) and neural continuity (on ultrasound and pyloric electromyography) were assessed. Functional assessment was performed using barium retention studies, endoscopy, manometry and fecal incontinence scores. RESULTS: Tension-free end-to-end anastomosis of the anterior vagus nerve to the right (n = 7) and left (n = 1) inferior rectal nerve was achieved. An intact left gastroepiploic pedicle, a healthy graft and neural continuity were visualized on perineal ultrasound. Electromyographic activity was noticed on neural stimulation. Endoscopy and barium studies showed voluntary antral contraction and contrast retention, respectively, in all patients. The mean resting and squeeze pressures were 26.25 mmHg (range 16-62 mmHg) and 50.25 mmHg (range 16-113 mmHg), respectively. St. Mark's incontinence scores varied between 7 and 12. There were no major surgical complications. CONCLUSIONS: Pudendal (inferior rectal) innervation of the perineally transposed antropylorus in total anorectal reconstruction is feasible and may improve outcomes in selected patients with end-stage fecal incontinence.

Topographic anatomy and laparoscopic technique for dissection of no. 6 infrapyloric lymph nodes in gastric cancer surgery.

We focused on the embryology and topographic anatomy of the infrapyloric lymph region, which is frequently involved in node metastases but technically complicated for dissection in gastric cancer surgery. Gastrointestinal organs possess their own mesenteries composed of double layers of peritoneum that enclose the intermediate adipose layer providing pathways for vessels, nerves, and lymphatic channels. The frontal layer of the mesoduodenum, in which no. 6 infrapyloric nodes lie, directly faces the pancreas and during gestation is overlain by the greater omentum and transverse mesocolon through the membranous connective tissue called the fusion fascia. Therefore, we performed no. 6 node dissection using the following process: (1) we traced out the mesoduodenum by detachment of the greater omentum and transverse mesocolon; (2) we transected the fusion fascia and (3) removed the adipose layer on the anterior face of the pancreas with its included lymph nodes together with the right gastroepiploic and infrapyloric vessels. The described technique is feasible and in keeping with the anatomical logic for oncologically reliable dissection of no. 6 infrapyloric nodes.

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

PURPOSE: 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. METHODS: 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. RESULTS: 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. CONCLUSIONS: 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.

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

BACKGROUND: The 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. METHODS: Electronic 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. RESULTS: A 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. CONCLUSIONS: Surgeons 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.

Patients' preoperative background causes gastric stasis after laparoscopy-assisted pylorus-preserving gastrectomy.

INTRODUCTION: Despite technical improvements in laparoscopic gastrectomy, gastric stasis is still a serious problem in laparoscopy-assisted pylorus-preserving gastrectomy (LAPPG). The aim of this study was to investigate the factors that might cause gastric stasis in LAPPG. METHODS: From April 2004 through November 2012, 85 patients with cT1N0 middle-third gastric cancer who underwent LAPPG at Kitasato University Hospital; these patients were included in the present study. Infra-pyloric vein (IPV)-preserving LAPPG was performed in 41 patients. We compared the rate of gastric stasis in the IPV-preserving and the IPV-non-preserving groups, and analyzed the clinicopathological factors that might have caused gastric stasis. RESULTS: We did not demonstrate that preservation of the IPV could prevent gastric stasis in the early and late postoperative periods. Symptoms of gastric stasis were most frequently recognized 1 year after surgery. A significantly higher proportion of preoperative ASA class 2 patients had gastric stasis than did not (80.0% [12/15] vs 48.6% [34/70], P=0.02). Among the ASA class 2 patients, a significantly greater proportion of those with depressed activities of daily living than those with normal activities of daily living had gastric stasis (66.7% [4/6] vs 20.0% [8/40], P = 0.015). CONCLUSIONS: The clinical significance of the IPV preservation in LAPPG could not be demonstrated. LAPPG should be performed for ASA class 1 patients or those with maintained preoperative activities of daily living.

Bombesin-like immunoreactive material in the gut, and the effect of bombesin on the stomach circulatory system of an elasmobranch fish, Squalus acanthias.

The distribution, nature and amount of bombesin-like immunoreactivity (IR) in the gastrointestinal canal and its afferent vessels was investigated in the spiny dogfish (Squalus acanthias) together with the in vitro effect of synthetic bombesin on perfusion flow through the vascularly perfused dogfish stomach. Nerve fibres showing bombesin-like IR frequently occurred in the walls of the anterior mesenteric and coeliac arteries and the intrinsic vessels of the gut. Chromatographic studies revealed that multiple peaks of bombesin-like IR material were present in extracts of the spiny dogfish gastrointestinal vessels. Bombesin-like IR was also present in muscle and mucosal layers of the gut with higher levels in muscle compared with mucosa, and higher levels in the stomach than in the intestine and the rectum. Exogenous bombesin increased the flow through the vasculary perfused spiny dogfish stomach in a dose-dependent manner. Studies with tetrodotoxin and atropine showed that bombesin probably exerts its effect directly on the vascular musculature. It is concluded from this study that bombesin-like material is present in nerves innervating the gut circulatory system of the spiny dogfish. Bombesin may affect the blood-flow to the gastrointestinal canal, possibly via a direct effect on vascular smooth muscle.

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.

Pyloric preservation with the Whipple procedure.

The pylorus-preserving pancreatoduodenectomy simplifies resection, allows a satisfactory postoperative weight gain, prevents postgastrectomy symptoms, is followed by a low rate of jejunal ulceration, and can be performed with an extremely low postoperative mortality rate, providing that the pancreatic and biliary anastomoses are constructed so that no leakage occurs. Preliminary data indicate a satisfactory survival rate when this procedure is used for periampullary cancer, and reasonable relief of pain is achieved when the procedure is used in chronic pancreatitis.

Diagnosis of angiodysplasia on the caudal aspect of the pylorus: need for side-viewing endoscopy.

Recurrent gastrointestinal bleeding in patients with upper gastrointestinal angiodysplasia is common after treatment. This probably is related to the difficulty identifying all the lesions because they frequently are multiple and can be located in areas not easily visualized with forward-viewing endoscopy. We report two cases of patients with gastrointestinal bleeding in whom angiodysplasia as found at surgical enteroscopy on the caudal aspect of the pylorus that could not be identified with forward-viewing endoscopy. The lesions were ablated at the time of surgery or subsequently after location with side-viewing endoscopy, and no further bleeding occurred.

[Microvascular changes in the pyloric ring and duodenal invasion in carcinoma of the gastric antrum].

In this study, vascular perfusion of surgically removed specimen was carried out in 45 middle or late staged gastric antrum carcinomas and 5 gastric ulcers to observe the morphology of the microvasculature at the juncture of the stomach and the duodenum. It was found that: 1) The microvasculature on both side of the pylorus and the duodenum communicated through small arteriole and the morphology of the microvasculature varied with tumor-infiltrated depth. 2) The duodenum was found to be invaded by the tumor in only 2 cases in which the tumor was within 1.5 cm from the pyloric ring. 3) The mechanism by which the tumor invaded the duodenum was most likely resulted from direct extension through the interstitium when the microvasculature, the physiological and anatomical intact of the pyloric ring were destroyed by the tumor. 4) Based on the aforementioned observations, the authors propose that in gastric antrum carcinoma, the safe resection length of the duodenum is less than 3 cm when the tumor is 1.5 cm away from the pyloric ring, otherwise, more than 3 cm of the duodenum should be removed.

Thromboxane A2 antagonistic action of a new anti-ulcer agent, azuletil sodium (KT1-32).

The TXA2/PGH2 receptor antagonistic activity of azuletil sodium (KT1-32), a new anti-ulcer agent, was examined. KT1-32 competitively antagonized the contraction of canine gastric arteries induced by U-46619, PGF2 alpha, and PGE2, whereas it had no effect on the PGF2 alpha-, PGE2- and LTD4-induced contraction of guinea-pig ileum, which was not affected by U-46619. In anesthetized dogs, KT1-32 significantly reduced the U-46619-induced decrease in gastric arterial blood flow. Gastric contraction induced by U-46619 in anesthetized rats was markedly inhibited by KT1-32. KT1-32 showed no influence on TXA2 synthetase and cyclooxygenase activities. These results indicate that KT1-32 is a competitive TXA2/PGH2 receptor antagonist, which may be important as to the effectiveness of KT1-32 against gastric ulcer.

[The influence of corvitin on secretory processes and blood flow in the rat gastric mucosa].

We studied parameters of gastric secretion in pylorus-ligated rat and blood flow in the rat gastric mucosa under the influence of drug corvitin used intragastrically in doses of 2.5 and 5 mg/kg. Biochemical analysis of gastric juice was based on the determination of pH, total hydrochloric acid production and total protein, hexosamine and cysteine concentration. Gastric juice analysis in control rats found the presence of hexosamines-- a gastric mucus indicators and cysteine--free amino acid whith properties of a strong antioxidant. Concentration of these compounds in the gastric juice increased as a consequence of corvitin action. However, corvitin did not affect at these parameters of gastric secretion as the volume of gastric juice, pH, hydrochloric acid output rate, protein concentration. Additionally it was shown that corvitin in dose-dependent manner increased blood flow in the gastric mucosa. This results give reason to believe that corvitin can be considered as a tool that amplifies gastric mucosal defense mechanisms without affecting the secretion of gastric hydrochloric acid and total protein.

A challenging case of epigastric pain: diagnosis and mini-invasive treatment of a large gastroduodenal artery pseudoaneurysm.

The authors present a case of a gastroduodenal artery pseudoaneurysm in a patient with a medical history of pancreatic surgery. The lesion was found and evaluated by ultrasound, CT-angiography and then treated with trans-catheter embolisation. This mini-invasive approach led to a complete resolution of the lesion.