Deceased Donor Liver Transplantation With Hepatic Artery Aneurysm.

Few case reports have documented the long-term outcomes of liver donor aneurysms, illustrating the apprehension of transplant surgeons about using these grafts. However,the presence of an aneurysm in the donor liver should not be an absolute contraindication for its use. As shown in our described patient, such grafts have the potential to achieve good results.

Influence of aberrant right hepatic artery on survival after pancreatic resection for ductal adenocarcinoma of the pancreatic head.

PURPOSE: The presence of an aberrant right hepatic artery (aRHA), arising from the superior mesenteric artery, is a common variant of the liver vascular anatomy. Considering that tumor spread occurs along vessels, the question arises, whether the presence of an aRHA influences the oncologic outcome after resection for cancer of the pancreatic head. METHODS: Patients with ductal adenocarcinoma of the pancreatic head, who underwent resection from 2011 to 2020 at the Frankfurt University Hospital, Germany, were analyzed retrospectively. Surgical records and computed tomography imaging were reviewed for the presence of aRHA. Overall and disease-free survival as well as hepatic recurrence were analyzed according to the presence of aRHA. RESULTS: aRHA was detected in 21 out of 145 patients (14.5%). The median overall survival was 26 months (95%CI 20.8-34.4), median disease-free survival was 12.1 months (95%CI 8.1-17.3). There was no significant difference in overall survival (26.1 versus 21.4 months, adjusted hazard ratio 1.31, 95%CI 0.7-2.46, p = 0.401) or disease-free survival (14.5 months versus 12 months, adjusted hazard ratio 0.98, 95%CI 0.57-1.71, p = 0.957) without and with aRHA. The hepatic recurrence rate was 24.4.% with conventional anatomy versus 30.8% with aRHA (adjusted odds ratio 1.36, 95%CI 0.3-5.38, p = 0.669). In the multivariable analysis, only lymphatic vessel invasion was an independent prognostic factor for hepatic recurrence. CONCLUSIONS: The presence of an aRHA does not seem to influence the long-term survival and hepatic recurrence after resection for ductal adenocarcinoma of the pancreatic head.

Anastomosis selection in liver transplantation for recipients with unusable recipient hepatic arteries: a bayesian network meta-analysis.

BACKGROUND: The anastomosis of donor and recipient hepatic arteries is standard in liver transplantations. For transplant recipients with unusable hepatic arteries, appropriate artery selection should be conducted using evidence-based considerations; therefore, this network meta-analysis (NMA) aimed to analyze the most suitable alternative recipient artery for anastomosis during liver transplantations. METHODS: Comprehensive searches of the Scopus, Cochrane Library, and MEDLINE databases were conducted to analyze observational studies containing non-standard anastomoses in liver transplantations that used the splenic artery, aorta, celiac, or branches of the gastric artery. The outcome parameters included intraoperative components, complications, and survival data. This NMA used the BUGSnet package in R studio and the results were presented in a Forest plot, league table, and SUCRA plot. RESULTS: Among the 13 studies included in this NMA, 5 arteries were used for the anastomoses. The splenic artery anastomosis showed a high risk of thrombosis and a low risk of stenosis (OR 1.12, 95% CI 0.13-3.14) and biliary tract abnormalities (OR 0.79, 95% CI 0.36-1.55). In addition, the graft survival (OR 1.08; 95% CI 0.96-1.23) and overall survival (1-year survival OR 1.09, 95% CI 0.94-1.26; 5-year survival OR 1.95% CI 0.83-1.22) showed favorable results using this artery. Constraints to the use of the splenic artery were longer operation and cold ischemic times. However, the duration of hospital stay (MD 1.36, 95% CI -7.47 to 10.8) was shorter than that when the other arteries were used, and the need for blood transfusions was minimal (MD -1.74, 95% CI -10.2 to 6.7). CONCLUSION: In recipients with unusable hepatic arteries, the splenic artery of the patient should be the first consideration for anastomosis selection in liver transplantations.

Safe suprapancreatic lymph node dissection for gastric cancer with ectopic common hepatic artery.

Suprapancreatic lymph node dissection for patients with gastric cancer in whom the common hepatic artery is located neither at the suprapancreatic margin nor in front of the portal vein is a more difficult procedure than when the common hepatic artery is in a more typical position. There is an increased risk of injury to the vessels that need to be preserved and inadequate lymph node dissection. Measures that have been reported for use in this situation are preoperative diagnosis with three-dimensional computed tomography angiography, dissection using the portal vain as a guide, and safe exposure of the portal vein with dissection to preserve the nerves at the suprapancreatic margin and in front of the portal vein. We review the literature and report our experience with a patient whose common hepatic artery was not located in the suprapancreatic margin who safely underwent suprapancreatic lymph node dissection using these methods.

Robotic Versus Open Hepatic Arterial Infusion Pump Placement for Unresectable Intrahepatic Cholangiocarcinoma.

BACKGROUND: Hepatic arterial infusion pump (HAIP) chemotherapy is an effective treatment for patients with unresectable intrahepatic cholangiocarcinoma (iCCA). HAIP chemotherapy requires a catheter inserted in the gastroduodenal artery and a subcutaneous pump. The catheter can be placed using an open or robotic approach. OBJECTIVE: This study aimed to compare perioperative outcomes of robotic versus open HAIP placement in patients with unresectable iCCA. METHODS: We analyzed patients with unresectable iCCA included in the PUMP-II trial from January 2020 to September 2022 undergoing robotic or open HAIP placement at Amsterdam UMC, Erasmus MC, and UMC Utrecht. The primary outcome was time to functional recovery (TTFR). RESULTS: In total, 22 robotic and 28 open HAIP placements were performed. The median TTFR was 2 days after robotic placement versus 5 days after open HAIP placement (p < 0.001). One patient (4.5%) in the robotic group underwent a conversion to open because of a large bulky tumor leaning on the hilum immobilizing the liver. Postoperative complications were similar-36% (8/22) after robotic placement versus 39% (11/28) after open placement (p = 1.000). The median length of hospital stay was shorter in the robotic group-3 versus 5 days (p < 0.001). All 22 robotic patients initiated HAIP chemotherapy post-surgery, i.e. 93% (26/28) in the open group (p = 0.497). The median time to start HAIP chemotherapy was 14 versus 18 days (p = 0.153). CONCLUSION: Robotic HAIP placement in patients with unresectable iCCA is a safe and effective procedure and is associated with a significantly shorter TTFR and hospital stay than open HAIP placement.

Anomalies of the right hepatic artery in periampullary cancer treatment: are pathological and clinical outcomes different? A single tertiary referral center retrospective analysis.

PURPOSE: Anomalies of the right hepatic artery (RHA) may represent an additional challenge in pancreatoduodenectomy (PD). The aim of this study is to assess the potential impact of variations in hepatic arterial anatomy on perioperative outcomes. METHODS: PDs performed for periampullary malignancies between 2017 and 2022 were retrospectively enrolled and subdivided in two groups: modal pattern of vascularization (MPV) and anomalous pattern of vascularization (APV). A propensity score matching (PSM) analysis was conducted to homogenize the two study populations. The two groups were then compared in terms of perioperative outcomes and pathological findings. RESULTS: Thirty-eight patients (16.3%) out of 232 presented a vascular anomaly: an accessory RHA in 7 cases (3%), a replaced RHA in 26 cases (11.2%), and a replaced HA in 5 cases (2.1%). After PSM, 76 MPV patients were compared to the 38 APV patients. The incidence rate of postoperative complications was comparable between the two study populations (p=0.2). Similarly, no difference was detected in terms of histopathological data, including margin status. No difference was noted in terms of intraoperative hemorrhage and vascular resection. CONCLUSION: When PDs are performed in high-volume centers, the presence of an APV of the RHA does not relate to a significant impact on perioperative complications. Moreover, no influence was noted on histopathological findings.

Early hepatic artery thrombosis treatments and outcomes: aorto-hepatic arterial conduit interposition or revision of anastomosis?

BACKGROUND: Hepatic artery thrombosis (HAT) is one of the critical conditions after an orthotopic liver transplant (OLT) and leads to severe problems if not corrected promptly. However, multiple treatments have been proposed for HAT, in which surgical revascularization with either auto-hepatic conduit interposition (AHCI) or revision of the anastomosis is more familiar indeed indicated for some patients and in specific situations. In this study, we want to evaluate the success and outcomes of treating early HAT (E-HAT), which defines HAT within 30 days after OLT with either of the surgical revascularization techniques. METHOD: In this retrospective study, we collected information from the medical records of patients who underwent either of the surgical revascularization procedures for E-HAT after OLT. Patients who needed early retransplantation (RT) or died without surgical intervention for E-HAT were excluded. Demographic data, OLT surgery information, and data regarding E-HAT were gathered. The study outcomes were secondary management for E-HAT in case of improper inflow, biliary complications (BC), RT, and death. RESULTS: A total of 37 adult patients with E-HAT after OLT included in this study. These E-HATs were diagnosed within a mean of 4.6 ± 3.6 days after OLT. Two patients had their HA revised for the initial management of E-HAT; however, it changed to AHCI intraoperatively and finally needed RT. Two and nine patients from the AHCI and revision groups had re-thrombosis (12.5% vs. 47.3%, respectively, p = 0.03). RT was used to manage rethrombosis in all patients of AHCI and two patients of the revision group (22.2%). In comparison to the AHCI, revision group had statistically insignificant higher rates of BC (47.4% vs. 31.2%); however, RT for nonvascular etiologies (12.5% vs. 5.3%) and death (12.5% vs. 10.5%) were nonsignificantly higher in AHCI group. All patients with more than one HA exploration who were in the revision group had BC; however, 28.5% of patients with just one HA exploration experienced BC (p < 0.001). CONCLUSION: Arterial conduit interposition seems a better approach for the initial management of E-HAT in comparison to revision of the HA anastomosis due to the lower risk of re-thrombosis and the number of HA explorations; indeed, BC, RT, and death remain because they are somewhat related to the ischemic event of E-HAT than to a surgical treatment itself.

Left Hepatectomy Combined with Right Hepatic Artery Resection and Reconstruction for Hilar Cholangiocarcinoma.

BACKGROUND: Hepatectomy combined with hepatic artery reconstruction in the operation for hilar cholangiocarcinoma (Klatskin tumor) is a challenging procedure. We present a video of left hepatectomy combined with right hepatic artery reconstruction for hilar cholangiocarcinoma. PATIENT AND METHODS: The patient was a 60-year-old male who presented with obstructive jaundice. The imaging examination showed that the confluence of left and right hepatic ducts and the wall of common hepatic duct were thickened, the local lumen was narrowed, the intrahepatic bile duct was dilated, and the right hepatic artery was invaded by tumors nearly 2.3 centimeters. Left hepatectomy with total caudate lobectomy, resection with reconstruction of right hepatic artery, hilar lymphadenectomy, and Roux-en-Y hepaticojejunostomy were performed. RESULTS: The operation time was 345 min, and the amount of bleeding was about 400 ml. There was no blood transfusion. The pathology showed poorly differentiated adenocarcinoma, with negative margins of common bile duct and right hepatic duct, and negative results of all lymph nodes. The patient's recovery was uneventful and he was discharged on postoperative day 14. The patient was disease free at 12-month follow-up evaluation. CONCLUSIONS: Hepatic artery resection and reconstruction procedure is safe and feasible for hilar cholangiocarcinoma in a highly tertiary hepatobiliary center.

Reconstruction of all hepatic arteries in right lobe grafts with 2 hepatic arteries and zero percent hepatic artery thrombosis.

Hepatic artery thrombosis (HAT) is a common cause of graft loss in living-donor liver transplantation, occurring in ~2.5%-8% of patients. Some right lobe grafts have 2 hepatic arteries (HAs), and the optimal reconstruction technique remains controversial. This study aimed to identify risk factors for HAT and to evaluate the efficacy of reconstructing 2 HAs in right lobe grafts. This retrospective, single-center study analyzed 1601 living-donor liver transplantation recipients with a right liver graft and divided them into 1 HA (n = 1524) and 2 HA (n = 77) groups. The reconstruction of all HAs was performed using a microscope with an interrupted suture. The primary outcome was any HAT event. Of the 1601 patients, 37.8% had a history of transcatheter arterial chemoembolization, and 130 underwent pretransplant hepatectomy. Extra-anatomical arterial reconstruction was performed in 38 cases (2.4%). HAT occurred in 1.2% of patients (20/1601) who underwent surgical revascularization. In the multivariate analysis, undergoing pretransplant hepatectomy ( p = 0.008), having a female donor ( p = 0.02), having a smaller graft-to-recipient weight ratio ( p = 0.002), and undergoing extra-anatomical reconstruction ( p = 0.001) were identified as risk factors for HAT. However, having 2 HA openings in right liver grafts was not a risk factor for HAT in our series. Kaplan-Meier survival analysis showed no significant difference in graft survival and patient survival rates between the 1 HA and 2 HA groups ( p = 0.09, p = 0.97). In our series, although the smaller HA in the 2 HA group should increase the risk of HAT, HAT did not occur in this group. Therefore, reconstructing both HAs when possible may be a reasonable approach in living-donor liver transplantation using a right liver graft with 2 HA openings.

Pedicled ligament flaps during pancreatoduodenectomy are associated with reduced hemorrhage from hepatic artery and gastroduodenal artery stump during pancreatoduodenectomy: a systematic review, meta-analysis and trial sequential analysis.

BACKGROUND: The aim of this study was to investigate whether pedicled ligament flaps (PLF) covering around the hepatic and gastroduodenal artery stump can provide better clinical outcomes in pancreatoduodenectomy (PD). METHODS: We conducted a comprehensive search of databases (inception to January 2023) to identify studies comparing PD with or without PLF covering the skeletonized arteries. The perioperative and postoperative outcomes were compared. Pooled odds ratios (ORs) with 95 % confidence intervals (CIs) were calculated using fixed-effects models. RESULTS: Ten studies were included in the qualitative synthesis. Six studies with 3538 patients met the inclusion criteria for the meta-analysis. Patients in the PLF group had a significantly lower rate of PPH from the hepatic artery or gastroduodenal artery stump (H/G PPH) (OR: 0.41; 95 % CI, 0.22-0.75; P < 0.01) and overall PPH (OR: 0.65; 95 % CI, 0.46-0.93; P = 0.02). There were no significant differences between the two groups in terms of morbidity, grade B/C postoperative pancreatic fistula (B/C POPF), delayed gastric emptying (DGE), reoperation, or mortality. CONCLUSION: Prophylactic pedicled ligament flaps covering around the skeletonized arteries significantly reduced overall PPH and H/G PPH, and it seemed to have no obvious influence on other complications.

Transarterial chemoembolization in a patient with the replaced right hepatic and left gastric arteries arising from the abdominal aorta: a new anatomical variation.

PURPOSE: Knowing the anatomical variation of the coeliac trunk (CT) and its detailed interpretation in the preoperative period is important for the prevention of iatrogenic injury during liver surgery or endovascular intervention on the coeliac trunk and its branches. METHODS: A diagnostic abdominal computed tomography angiography (CTA) was performed in a 61-year-old male patient, who was investigated for a liver cancer and chemoembolization was planned. RESULTS: CTA reveals that right hepatic artery (RHA) arises directly from the abdominal aorta, at the level of CT. This vessel coursing to the right hepatic lobe, functioning therefore as a replaced right hepatic artery (RRHA). Also, the left gastric artery (LGA) arises directly from the abdominal aorta. This patient successfully underwent chemoembolization from RRHA. CONCLUSION: We presented a case of new anatomical variation involving the origination of RRHA and LGA from the abdominal aorta.

A gastroduodenal artery that branched from the celiac artery in gastrectomy: A rare case of an anatomical variant.

Understanding anatomical anomalies of the branch of the celiac artery for safe gastrectomy is important. We report a case of laparoscopic distal gastrectomy with D1+ lymph node dissection for early gastric cancer with a vascular anatomical anomaly of the celiac artery. A 45-year-old woman was referred to our hospital because of early gastric cancer. Computed tomography showed an anatomical variation of the gastroduodenal artery, which branched from the celiac artery. The celiac artery also branched into the left gastric artery, the splenic artery, and the common hepatic artery. Preoperative understanding of an unusual branch of the celiac artery enabled a safe laparoscopic surgery. There were no postoperative complications. The Adachi classification or Michel classification is used for an anatomical anomaly of the celiac artery, but to the best of our knowledge, this case has not been previously classified and is the first reported case.

Hepatic arterial buffer response: activation in donor fetuses and the effect of laser ablation of intertwin anastomosis.

OBJECTIVES: Hepatic arterial buffer response (HABR) is an important defence mechanism for maintaining liver blood flow. It is suspected that HABR is active in monochorionic diamniotic twins (MCDA) with twin-to-twin transfusion syndrome (TTTS) where donor compensates a setting of volume depletion and the recipient an overload. The present study investigates whether in TTTS, HABR is active in donor and/or recipient individually and try to determine if the activation of HABR is a direct response to TTTS. METHODS: Hepatic artery (HA) peak systolic velocity (PSV) was measured in normal MCDA fetuses and TTTS. Correlation with relevant fetal Dopplers and characteristics were determined. Z-scores for HA-PSV (HAV-Z) were calculated and its association with TTTS in donors and recipients were determined as well as changes in HAV-Z after laser treatment. RESULTS: In this study 118 MCDA were included, 61.9 % normal and 38.1 % TTTS. Of the TTTS 22 required laser treatment. A total of 382 scans were performed in normal group and 155 in TTTS. Our data demonstrates that in donors HAV-Z was 2.4 Z-scores higher compared to normal fetuses (ß=2.429 95 % CI 1.887, 2.971; p<0.001) and after laser treatment HAV-Z reduced (ß=-1.829 95 % CI -2.593, -1.064; p<0.001). There was no significant difference between recipients and normal (ß=-0.092 95 % CI -0.633, 0.449; p=0.738). CONCLUSIONS: HABR is active in TTTS, promoting an increased hepatic blood flow in donors. The activation is direct response to TTTS as shown by the reduction in HAV-Z after laser. This finding provides important insights into the pathophysiology of TTTS.

Celiac trunk stenosis by median arcuate ligament in orthotopic liver transplantation: a potential hidden foe to the biliary tree.

BACKGROUND: Celiac trunk compression by the median arcuate ligament (MAL) increases the risk of ischemic complications following gastrointestinal surgical procedures. Previous studies suggest increased risk of hepatic artery thrombosis (HAT) in orthotopic liver transplant (OLT) recipients. The aim of this study is to investigate the impact of untreated MAL compression (MAL-C) on biliary complications in OLT. METHODS: Contrast-enhanced imaging was used to classify celiac trunk stenosis by MAL-C. Medical records were reviewed to extract pre-transplant, transplant and post-transplant data. Patients were divided into two groups: no MAL compression (nMAL-C) and MAL-C. The primary endpoint was biliary complications. Secondary endpoints were HAT and graft survival. RESULTS: 305 OLT were performed from 2010 to 2021, of which 219 were included for analysis: 185 (84.5%) patients without and 34 (15.5%) with MAL-C. The incidence of HAT was 5.9% in both groups. Biliary complications were more common in the MAL-C group (35.3% vs. 17.8%, p = 0.035). Graft survival was decreased in patients with MAL-C (p = 0.035). CONCLUSIONS: MAL-C of the celiac trunk was associated with increased risk of biliary complications and inferior graft survival in OLT patients. These findings highlight the importance of preoperative screening and treatment of MAL in this population.

Hepatic artery thrombosis and use of anticoagulants and antiplatelet agents in pediatric liver transplantation.

BACKGROUND: Hepatic artery thrombosis (HAT) is a reported complication of 5%-10% of pediatric liver transplantations, rates 3-4 times that seen in adults. Early HAT (seen within 14 days after transplant) can lead to severe allograft damage and possible urgent re-transplantation. In this report, we present our analysis of HAT in pediatric liver transplant from a national clinical database and examine the association of HAT with anticoagulant or antiplatelet medication administered in the post-operative period. METHODS: Data were obtained from the Pediatric Health Information System database maintained by the Children's Hospital Association. For each liver transplant recipient identified in a 10-year period, diagnosis, demographic, and medication data were collected and analyzed. RESULTS: Our findings showed an average rate of HAT of 6.3% across 31 centers. Anticoagulant and antiplatelet medication strategies varied distinctly among and even within centers, likely due to the fact there are no consensus guidelines. Notably, in centers with similar medication usage, HAT rates continue to vary. At the patient level, use of aspirin within the first 72 h of transplantation was associated with a decreased risk of HAT, consistent with other reports in the literature. CONCLUSION: We suggest that concerted efforts to standardize anticoagulation approaches in pediatric liver transplant may be of benefit in the prevention of HAT. A prospective multi-institutional study of regimen-possibly including aspirin-following transplantation could have significant value.

Hilar Anatomy in 3035 Living Liver Donors: A Novel Classification for Donor Surgery and Suitability, Hepatic Surgeries, and Hepatobiliary Interventions.

BACKGROUND: This study examines the vascular and biliary variations in 3035 liver donors. We propose a novel classification of hepatic arteries, portal veins, and bile ducts and clinically relevant donor classification. METHODS: Preoperative imaging and operative details of 3035 donors from 2005 to 2020 were reviewed. Hilar anatomical variations were identified and grouped on the basis of incidence and clinical relevance. RESULTS: Hilar structures are classified according to the numbers supplying or draining the graft: for the hepatic artery, right (R) and left (L), RA1/LA1 (1 artery), RA2/LA2 (2 arteries), and RA3/LA3 (3 arteries), respectively, further defined on the basis of the inflow trunk into C (for common hepatic artery), S (for superior mesenteric artery), and L (for left gastric artery); for the portal vein, RP1 (1 vein) and RP2 (2 veins) for the right lobe; and for the hepatic duct, RB1/LB1 (1 duct), RB2/LB2 (2 ducts), RB3 (3 right ducts), and RB4 (4 right ducts). Donors were classified on the basis of anatomical variations into 3 groups: class 1 and class 2 donors, who can donate liver with acceptable risks, and class 3 donors, who are high-risk donors because they are anatomically unacceptable ( Figures S1 to S4, SDC , http://links.lww.com/TP/C918 ). CONCLUSIONS: Defining hilar anatomical variations and donor grouping into anatomy-based clinical classes helps in operative planning of donors, hepatobiliary surgeries, and interventional procedures.

A systematic review meta-analysis and meta-regression on the implications of an aberrant right hepatic artery in patients undergoing pancreaticoduodenectomy for the treatment of malignant disease.

We investigated the outcomes of pancreaticoduodenectomy in the presence of an aberrant right hepatic artery (aRHA). We systematically reviewed Medline, Scopus, and Web of Science until April 2023 for studies comparing pancreaticoduodenectomy outcomes with and without aRHA. Endpoints included postoperative mortality, R0 resection margins, pancreatic fistulae, hemorrhage, biliary leak/fistulae, delayed gastric emptying, operative duration, and blood loss. Eight retrospective studies involving 1514 patients were included. The risk ratio (RR) for postoperative mortality and odds ratio (OR) for R0 resection between the aRHA and normal anatomy groups were 1.37 (95%CI:0.74-256) (I2=0%, P=0.99) and 1.03 (95%CI:0.67-1.59) (I2=10%, P=0.35). Besides a longer operative duration in the aRHA group, mean difference (MD) 54.64 (95% CI: 8.51-100.77) (I2=94%, P<0.01), there were no significant differences in secondary endpoints. Meta-regression revealed a significant association between aRHA reconstruction and postoperative mortality (ß=0.0179, P<0.01). This review displayed non-statistically significant differences in terms of surgical and oncological outcomes between patients with aRHA and patients with normal hepatic artery anatomy undergoing pancreaticoduodenectomy. However, the observed trend of increased postoperative mortality in patients with aRHA, combined with extended surgical duration and the link between aRHA reconstruction and postoperative mortality, prevents drawing definitive conclusions. Further research through high-quality studies is warranted.

An unusual presentation of a rare formation of the common hepatic duct and right hepatic artery in a case of pediatric congenital biliary dilatation.

A 15-year-old girl with recurrent upper abdominal pain was diagnosed with congenital biliary dilatation. Abdominal enhanced computed tomography (CT) showed the anterior segmental branch of the right hepatic artery (RHA) running across the ventral aspect of the dilated common hepatic duct (CHD). Laparoscopic extrahepatic dilated biliary duct excision and Roux-en-Y hepaticojejunostomy were planned. Intraoperatively, the dilated CHD was observed to bifurcate into the ventral and dorsal ducts, between which the anterior segmental branch of the RHA crossed through the CHD. The CHD rejoined on the distal side as one duct. We transected the CHD just above the cystic duct. The patency of the ventral and dorsal sides of the bifurcated CHD was confirmed. Laparoscopic hepaticojejunostomy was performed at the distal side of the rejoined CHD, without sacrificing the anterior segmental branch of the RHA. There was no postoperative blood flow impairment in the right hepatic lobe or anastomotic stenosis.