New approach of circumferential lymph node dissection around the superior mesenteric artery for pancreatic cancer during pancreaticoduodenectomy (with video).

PURPOSE: Various approaches have been reported for the resection of the nervous and lymphatic tissues around the superior mesenteric artery (SMA) during pancreaticoduodenectomy (PD) for pancreatic cancer. We developed a new procedure for circumferential lymph node dissection around the SMA to minimize local recurrence. METHODS: We included 24 patients who underwent PD with circumferential lymph node dissection around the SMA (circumferential dissection) and 94 patients who underwent classical mesopancreatic dissection (classical dissection) between 2019 and 2021. The technical details of this new method are described in the figures and videos, and the clinical characteristics and outcomes of this technique were compared with those of classical dissection. RESULTS: The median follow-up durations in the circumferential and classical dissection groups were 39 and 36 months, respectively. The patients' characteristics, including tumor resectability, preoperative and adjuvant chemotherapy rates, postoperative complication rates, and tumor stage, were similar between the two groups. No differences were observed in recurrence-free survival and overall survival between the two groups; however, the classical dissection group tended to have more local recurrences than the circumferential dissection group (8.3% vs. 33.3%, P = 0.168). Although no case of nodular-type recurrence after circumferential dissection was observed, 61.1% of local recurrences after classical dissection were of the nodular-type, and 36.4% were located on the left side of the SMA. CONCLUSIONS: Performing circumferential lymph node dissection around the SMA during PD can be conducted safely with minimal risks of local recurrence and may enhance the completeness of local resection.

Endovascular treatment of chronic mesenteric ischaemia secondary to a superior mesenteric artery pseudoaneurysm: a modified neurointerventional technique.

A man in his late 60s presented with intermittent abdominal pain, nausea, vomiting and approximately 40 pounds of weight loss over the course of a year, most concerning for chronic mesenteric ischaemia. Given a prior negative workup, a CT angiogram was performed and revealed a wide neck mid-superior mesenteric artery pseudoaneurysm (PSA). As PSAs are susceptible to thrombus formation and distal emboli, this incidental finding was considered a possible explanation for his intermittent symptoms and thus required treatment. Anatomical constraints precluded traditional coiling or covered stent placement, so the interventional radiology team used a neurointerventional technique and performed a successful balloon-assisted coil embolisation of the PSA with subsequent resolution of the patient's symptoms. More than 3 years postprocedure, the patient remains asymptomatic with no complications.

Isolated Superior Mesenteric Artery Vasculitis as a Cause of Abdominal Pain.

ABSTRACT: This manuscript demonstrates that although isolated superior mesenteric artery vasculitis that also could be called as localized vasculitis of the gastrointestinal tract was rare entity, it is so significant as differential diagnosis of abdominal pain in addition to idiopathic dissection, infective arteritis, and lymphoma. This case should remind readers to consider isolated superior mesenteric artery vasculitis as a cause of (upper) abdominal pain.

The pathogenesis of superior mesenteric artery dissection: An in-depth study based on fluid-structure interaction and histology analysis.

OBJECTIVE: To explore the role of hemodynamic factors in the occurrence of superior mesenteric artery (SMA) dissection (SMAD) using a fluid-structure interaction (FSI) simulation method, and to identify histopathologic changes occurring in the wall of the SMA. METHODS: A total of 122 consecutive patients diagnosed with SMAD and 122 controls were included in this study. Hemodynamic factors were calculated using a FSI simulation method. Additionally, SMA specimens obtained from 12 cadavers were stained for histological quantitative analysis. RESULTS: The mean aortomesenteric angle (59.7° ± 21.4° vs 48.2° ± 16.8°; p < .001) and SMA maximum curvature (0.084 ± 0.078 mm-1 vs 0.032 ± 0.023 mm-1; p < .001) were higher in SMAD patients than the controls. Larger aortomesenteric angles and SMA curvatures were associated with higher and more concentrated wall shear stress at anterior wall of the SMA curve segment, co-located with the dissection origins. The mean thickness of media (325.18 ± 44.87 µm vs 556.92 ± 138.32 µm; p = .003) was thinner in the anterior wall of the SMA curve than in the posterior wall. The area fractions of elastin (17.96% ± 3.36% vs 27.06% ± 4.18%; p = .002) and collagen (45.43% ± 6.89% vs 55.57% ± 7.57%; p = .036) were lower in anterior wall of the SMA curve than in posterior wall. CONCLUSION: Increased aortomesenteric angle and SMA curvature are risk factors for SMAD. Both of these factors can cause local hemodynamic abnormalities, which can lead to histopathologic changes in anterior wall of SMA.

Total laparoscopic radical antegrade modular pancreato-splenectomy with left-posterior superior mesenteric artery first-approach for distal pancreatic cancer: step-by-step technique with a surgical case report (with video).

INTRODUCTION: Left-sided pancreatic cancers are uncommon but seem more aggressive than tumors of pancreatic head. Radical antegrade modular pancreato-splenectomy (RAMPS) was proved to have safe and effective advantages while comparing with standard retrograde pancreato-splenectomy (SRPS) in recent systematic literature reviews and meta-analyses. Laparoscopic SMA first-approach RAMPS was recently proceeded with optimistic perioperative outcomes. CASE PRESENTATION: Our patient is a 67-year-old female with a medical history of diabetes and hypertension, recruited because of upper left quadrant abdominal pain. She was referred for pancreato-splenectomy because of a 3-cm-sized mass in distal pancreas. We use 5 trocars and the patient placed in a Trendelenburg position. The retroperitoneum is opened at the left-posterior side of the meso-pancreato-duodenum along to the inframesocolic space, so that the anterior surface of the aorta (AO), inferior vena cave (IVC), left renal vein (LRV), left adrenal grand (LAG), and kidney are completely exposed. The inferior border of the pancreas had been dissected and separated from the superior mesenteric vein (SMV) below the pancreatic isthmus, removed the lymph nodes (LNs) groups 14v and 17. Then, dissect of LNs groups 7,8,9,11p,12 en bloc at the superior side of the pancreas. Dissection of LNs group 14p, d or SMA LNs after transecting the pancreas. The operation time was 240 min, the estimated blood loss was 200 ml. With no postoperative complications as well as no diarrhea, the patient was discharged on the POD10 uneventfully. Pathological result: pancreatic ductal adenocarcinoma with T2N1 staging and negative margin (R0). CONCLUSIONS: This technique was safe and effective to perform precise and complete lymphadenectomy and negative posterior resection in total laparoscopic left-posterior SMA first-approach RAMPS for distal pancreatic cancer.

2021 SSAT Debate: Selective Approach to Resection of the Superior Mesenteric Artery in Pancreatic Cancer vs Superior Mesenteric Artery Encasement Is Not an Absolute Contraindication for Surgery in Pancreatic Cancer.

OVERVIEW: This manuscript summarizes an excellent debate from the 2021 SSAT/Pancreas Club symposium on arterial resection in pancreas cancer. Two world-recognized experts, Professor Ugo Boggi from Pisa, IT, and Dr. Mark Truty from the Mayo Clinic in Rochester, MN, offered their views on the role of arterial resection in locally advanced pancreas ductal adenocarcinoma. Both speakers have extensive experience pushing the technical envelope with extended vascular resection in pancreatectomy. However, both highlight important concepts of resectability extending well beyond technique: namely, patient global physiology, tumor biology, and response to chemotherapy. The debate was spirited, and this subsequent review is an excellent look at the status quo. N. J. Zyromski, MD, Indianpolis, IN, November, 2021.

Ultrasound evaluation of bowel vasculopathy in systemic sclerosis.

BACKGROUND: Gastrointestinal (GI) manifestations are frequent in systemic sclerosis (SSc) with an impact on quality of life and morbidity. Bowel vasculopathy is a key pathogenetic factor responsible for GI involvement. OBJECTIVES: To compare abdominal ultrasound (US) and Color Doppler Ultrasonography (CDU) features of splanchnic vessels of SSc patients with healthy controls. METHODS: The charts of SSc patients who underwent an abdominal US and CDU study were retrospectively analyzed. For Superior Mesenteric Artery (SMA) and Inferior Mesenteric Artery (IMA) caliber, Peak Systolic Velocity (PSV), Reverse Velocity (RV), End-Diastolic Velocity (EDV), Mean Velocity (mV), Blood-flow, Resistive Index (RI) and Pulsatility Index (PI) were recorded. RESULTS: 28 SSc patients and 28 controls were enrolled. In SSc, caliber of SMA was significantly smaller than in controls (5.75 ± 0.62 mm vs. 6.45 ± 0.60 mm, p < 0.0001 - p adj =0.0002). The flow study of SMA and IMA showed a significant reduction of RV (SMA: 7.25 ± 6.37 cm/s vs. 18.52 ± 6.16 cm/s, p < 0.0001 - p adj <0.0001; IMA: 2.69 ± 6.10 cm/s vs. 17.06 ± 5.75 cm/s, p < 0.0001 - p adj <0.0001) and PI (SMA: 3.33 ± 0.75 vs. 4.53 ± 1.03, p < 0.0001 - p adj =0.0002; IMA: 3.54 ± 0.95 vs. 6.08 ± 1.53, p < 0.0001 - p adj <0.0001) in SSc patients than controls. CONCLUSION: involvement of splanchnic vessels in SSc may be non-invasively investigated with abdominal US and CDU. Morphological and functional changes of Doppler parameters observed in SMA and IMA clearly demonstrate that these vessels are affected by SSc vasculopathy.

Reduced Relaxant Response to Adenine in the Superior Mesenteric Artery of Spontaneously Hypertensive Rats.

We investigated the vascular response to nucleobase adenine using freshly isolated superior mesenteric arteries of spontaneously hypertensive rats (SHR) and its control, Wistar Kyoto (WKY) rats. Endothelium-dependent and endothelium-independent relaxations were assessed in isolated segments in an organ bath. The releases of the metabolites of thromboxane A2 and prostaglandin I2 were also detected. Adenine induced vasorelaxation in both the endothelium-intact and endothelium-denuded arteries in a concentration-dependent manner. In the SHR group, the adenine-induced relaxation was slightly but significantly reduced in the endothelium-intact rings when compared with that in the WKY group. However, the relaxation in the endothelium-denuded rings were similar between the two groups. The difference in the adenine-mediated relaxation in the superior mesenteric arteries between the SHR and WKY groups was eliminated by endothelial denudation and a nitric oxide (NO) synthase inhibitor. In the absence and presence of adenine, SHR tended to have higher levels of metabolites of thromboxane A2 and prostaglandin I2 compared with WKY. However, adenine did not induce the release of these substances in the arteries in both the SHR and WKY groups. These results suggest that the reduced adenine-mediated relaxation in the superior mesenteric arteries in SHR is due to a lack of contribution from the endothelium-derived NO and not from the release of prostanoids.

CT Radiomic Features of Superior Mesenteric Artery Involvement in Pancreatic Ductal Adenocarcinoma: A Pilot Study.

Background Current imaging methods for prediction of complete margin resection (R0) in patients with pancreatic ductal adenocarcinoma (PDAC) are not reliable. Purpose To investigate whether tumor-related and perivascular CT radiomic features improve preoperative assessment of arterial involvement in patients with surgically proven PDAC. Materials and Methods This retrospective study included consecutive patients with PDAC who underwent surgery after preoperative CT between 2012 and 2019. A three-dimensional segmentation of PDAC and perivascular tissue surrounding the superior mesenteric artery (SMA) was performed on preoperative CT images with radiomic features extracted to characterize morphology, intensity, texture, and task-based spatial information. The reference standard was the pathologic SMA margin status of the surgical sample: SMA involved (tumor cells ≤1 mm from margin) versus SMA not involved (tumor cells >1 mm from margin). The preoperative assessment of SMA involvement by a fellowship-trained radiologist in multidisciplinary consensus was the comparison. High reproducibility (intraclass correlation coefficient, 0.7) and the Kolmogorov-Smirnov test were used to select features included in the logistic regression model. Results A total of 194 patients (median age, 66 years; interquartile range, 60-71 years; age range, 36-85 years; 99 men) were evaluated. Aside from surgery, 148 patients underwent neoadjuvant therapy. A total of 141 patients' samples did not involve SMA, whereas 53 involved SMA. A total of 1695 CT radiomic features were extracted. The model with five features (maximum hugging angle, maximum diameter, logarithm robust mean absolute deviation, minimum distance, square gray level co-occurrence matrix correlation) showed a better performance compared with the radiologist assessment (model vs radiologist area under the curve, 0.71 [95% CI: 0.62, 0.79] vs 0.54 [95% CI: 0.50, 0.59]; P < .001). The model showed a sensitivity of 62% (33 of 53 patients) (95% CI: 51, 77) and a specificity of 77% (108 of 141 patients) (95% CI: 60, 84). Conclusion A model based on tumor-related and perivascular CT radiomic features improved the detection of superior mesenteric artery involvement in patients with pancreatic ductal adenocarcinoma. © RSNA, 2021 Online supplemental material is available for this article. See also the editorial by Do and Kambadakone in this issue.

Paraaortic dissection in "total mesopancreas excision" and "mesopancreas-first resection" pancreaticoduodenectomies for pancreatic cancer: Useless, optional, or necessary?A systematic review.

The mesopancreas does not have well-defined boundaries but is continuous and connected through its components with the paraaortic area. The mesopancreatic resection margin has been indicated as the primary site for R1 resection after PD in pancreatic head cancer and total mesopancreas excision has been proposed to achieve adequate retropancreatic margin clearance and to minimize the likelihood of R1 resection. However, the anatomy of the mesopancreas requires extended dissection of the paraaortic area to maximize posterior clearance. The artery-first surgical approach has been developed to increase local radicality at the mesopancreatic resection margin. During PD, the artery-first approach begins with dissection of the connective tissues around the SMA. However, the concept of the mesopancreas as a boundless structure that includes circumferential tissues around the SMA, SMV, and paraaortic tissue highlights the need to shift from artery-first PD to mesopancreas-first PD to reduce the risk of R1 resection. From this perspective the "artery-first" approach, which allows for the avoidance of R2 resection risk, should be integrated into the "mesopancreas-first" approach to improve the R0 resection rate. In total mesopancreas excision and mesopancreas-first pancreaticoduodenectomies, the inclusion of the paraaortic area and circumferential area around the SMA in the resection field is necessary to control the tumour spread along the mesopancreatic resection margin rather than to control or stage the spread in the nodal basin.

The Medial Border of Laparoscopic D3 Lymphadenectomy for Right Colon Cancer: Results from an Exploratory Pilot Study.

BACKGROUND: Opinions vary on the medial border of D3 lymphadenectomy for right colon cancer. Most surgeons place the medial border along the left side of the superior mesenteric vein, but some consider the left side of the superior mesenteric artery as the medial border. OBJECTIVES: This study investigated the clinical outcomes of laparoscopic D3 lymphadenectomy for right colon cancer with the medial border along the left side of superior mesenteric artery. DESIGN: This was a retrospective study. SETTINGS: The study was conducted in specialized colorectal cancer department of 5 tertiary hospitals. PATIENTS: Patients receiving laparoscopic D3 lymphadenectomy for right colon cancer from January 2013 to December 2018 were included. MAIN OUTCOME MEASURES: After propensity score matching, 307 patients receiving laparoscopic D3 lymphadenectomy along the left side of the superior mesenteric artery were assigned to the superior mesenteric artery group and 614 patients were assigned to the superior mesenteric vein group. Univariate, multivariate, and Kaplan-Meier analyses were performed to assess the clinical data. RESULTS: The short-term outcomes were similar between the 2 groups; however, the superior mesenteric artery group had a higher rate of chylous leakage (p < 0.001). More lymph nodes were harvested from the superior mesenteric artery group than from the superior mesenteric vein group (p = 0.001). The number (p = 0.005) of metastatic lymph nodes and the lymph node ratio (p = 0.041) in main nodes were both higher in the superior mesenteric artery group. The 2 groups had similar long-term survival, but the superior mesenteric artery group tended to show better disease-free survival in patients with stage disease III (p = 0.056). LIMITATIONS: This was a retrospective, nonrandomized study. CONCLUSION: Laparoscopic D3 lymphadenectomy along the left side of the superior mesenteric artery, except for a higher rate of chylous leakage, had short-term outcomes comparable to the superior mesenteric vein group. The superior mesenteric artery group tended to achieve better disease-free survival in patients with stage III disease, but further study is required to better elucidate differences in these approaches because risks/benefits do exist.

Natural History of Asymptomatic Superior Mesenteric Arterial Stenosis Depends on Coeliac and Inferior Mesenteric Artery Status.

OBJECTIVE: The benefit of preventive treatment for superior mesenteric artery (SMA) stenosis remains uncertain. The latest European Society for Vascular Surgery (ESVS) guidelines remain unclear given the lack of data in the literature. The aim of this study was to evaluate asymptomatic SMA stenosis prognosis according to the presence of associated coeliac artery (CA) and/or inferior mesenteric artery (IMA) stenosis. METHODS: This was a single academic centre retrospective study. The entire computed tomography (CT) database of a single tertiary hospital was reviewed from 2009 to 2016. Two groups were defined: patients with isolated > 70% SMA stenosis (group A) and patients with both SMA and CA and/or IMA > 70% stenosis (group B). Patient medical histories were reviewed to determine the occurrence of mesenteric disease (MD) defined as development of acute mesenteric ischaemia (AMI) or chronic mesenteric ischaemia (CMI). RESULTS: Seventy-seven patients were included. Median follow up was 39 months. There were 24 patients in group A and 53 patients in group B. In group B, eight (10.4%) patients developed MD with a median onset of 50 months. AMI occurred in five patients with a median of 33 months and CMI in three patients with a median of 88 months. Patients of group B developed more MD (0% vs. 15.1%; p = .052). The five year survival rate was 45% without significant difference between groups. CONCLUSION: Patients with SMA stenosis associated with CA and/or IMA seem to have a higher risk of developing mesenteric ischaemia than patients with isolated SMA stenosis. Considering the low life expectancy of these patients, cardiovascular risk factor assessment and optimisation of medical treatment is essential. Preventive endovascular revascularisation could be discussed for patients with non-isolated > 70% SMA stenosis, taking into account life expectancy.

Extraordinary first jejunal arterial variation associated with annular pancreas undergoing pancreaticoduodenectomy for pancreatic cancer: a case report.

PURPOSE: Annular pancreas encountered in adults and jejunal arterial variations are rare. Anatomical variations can cause conflicts between oncology and surgical safety. METHODS: Case report of a 68-year-old man suffering from vomiting because of an annular pancreas and a ductal adenocarcinoma of the pancreas head invading the second portion of the duodenum. RESULTS: Contrast-enhanced computed tomography showed multiple arterial variations describing the absence of the coeliac trunk such that the left gastric artery (LGA), splenic artery and superior mesenteric artery (SMA) were arising separately from the aorta. The accessory left hepatic artery arose from the LGA; and both the common hepatic artery and combined trunk of the replaced right hepatic artery with the higher replaced first jejunal artery separately arose close to the root of the SMA. The patient underwent curative pancreaticoduodenectomy which achieved 3 years of recurrence-free survival. CONCLUSION: This was an extraordinary case of annular pancreas with first jejunal arterial variation detailing an embryological interpretation as well as considerations for balancing short- and long-term outcomes.

The Incidence of Chronic Mesenteric Ischemia in the Well-Defined Region of a Dutch Mesenteric Ischemia Expert Center.

INTRODUCTION: This study aimed to determine the incidence of chronic mesenteric ischemia (CMI) and to examine the influence of the etiological cause, location, and severity of a mesenteric artery stenosis on the probability of having CMI. METHODS: A prospective database, containing the details of all patients with suspected CMI referred to a renowned CMI expert center, was used. Patients residing within the expert centers' well-defined region, between January 2014 and October 2019, were included. CMI was diagnosed when patients experienced sustained symptom improvement after treatment. RESULTS: This study included 358 patients, 75 had a ≥50% atherosclerotic stenosis of 1 vessel (CMI 16%), 96 of 2 or 3 vessels (CMI 81%), 81 celiac artery compression (CMI 25%), and 84 no stenosis (CMI 12%). In total, 138 patients were diagnosed with CMI, rendering a mean incidence of 9.2 (95% confidence interval [CI] 6.2-13.7) per 100,000 inhabitants. Atherosclerotic CMI was most common, with a mean incidence of 7.2 (95% CI 4.6-11.3), followed by median arcuate ligament syndrome 1.3 (95% CI 0.5-3.6) and chronic nonocclusive mesenteric ischemia 0.6 (95% CI 0.2-2.6). The incidence of CMI was highest in female patients (female patients 12.0 [95% CI 7.3-19.6] vs male patients 6.5 [95% CI 3.4-12.5]) and increased with age. CMI was more prevalent in the presence of a ≥70% atherosclerotic single-vessel stenosis of the superior mesenteric artery (40.6%) than the celiac artery (5.6%). DISCUSSION: The incidence of CMI is higher than previously believed and increases with age. Probability of CMI seems highest in suspected CMI patients with multivessel disease or a ≥70% atherosclerotic single-vessel superior mesenteric artery stenosis.

Effect of visceral fat tissue on superior mesenteric artery configuration: Is it superior to BMI?

BACKGROUND/AIMS: To determine the effect of visceral fat volume measured via computed tomography (CT) images of umbilical slices on superior mesenteric artery (SMA) configuration, as compared with body mass index (BMI). In addition, this study aims to determine the effect of lumbar lordosis angle (LLA) on SMA configuration. MATERIALS AND METHODS: The study included 310 patients who underwent abdominal CT. On CT images, the aortomesenteric angle (AMA), the distance between SMA and aorta at three levels, and LLA were measured. Visceral fat volume was measured using three consecutive images obtained at the level of the umbilicus. The relationship among AMA, and distances measured between SMA and aorta, and visceral fat tissue volume were determined. The effect of LLA on AMA and distances measured between SMA and aorta was analyzed. RESULTS: There was a significant positive correlation between visceral fat volume, and patient age, AMA, distances between SMA and aorta, LLA, and BMI (p<0.001). There were not any significant differences in AMA, distances between SMA and aorta, BMI, or visceral fat volume between the patients with an LLA of 20°-45° and those with an LLA >45° (p>0.05). There was a significant positive correlation between BMI, and AMA, distances between SMA and aorta (p<0.001). There was a significant positive correlation between visceral fat volume, and AMA, distances between SMA and aorta (p<0.001). CONCLUSION: Visceral fat tissue volume is more valuable than BMI for evaluating the SMA configuration.

Protein-losing enteropathy as a complication of spontaneous isolated superior mesenteric artery dissection: A case report.

INTRODUCTION: Protein-losing enteropathy and spontaneous isolated superior mesenteric artery dissection are both rare clinically. Protein-losing enteropathy due to superior mesenteric artery dissection is extremely rare. PATIENT CONCERNS: A 46-year-old male with acute abdominal pain and hematochezia was diagnosed with a complete occlusion of the superior mesenteric artery because of dissection. He suffered from diarrhea and hypoproteinemia after an emergency thromboendarterectomy. DIAGNOSES: Based on laboratory tests and capsule endoscopy inspection, a diagnosis of protein-losing enteropathy was made. INTERVENTIONS: Endovascular treatment was provided. OUTCOMES: After stent placement, he quickly recovered without a recurrence of symptoms. CONCLUSION: Protein-losing enteropathy is a serious complication of an isolated superior mesenteric artery dissection. Restoring the patency of the superior mesenteric artery is keyed for the treatment of this complication.

Inferior Pancreatico-Duodenal Artery Aneurysm with Superior Mesenteric Artery Stenosis.

Pancreatico-duodenal artery aneurysm (PDAA) associated with stenosis or occlusion of the celiac trunk is a rare condition. Furthermore, PDAAs associated with stenosis of the superior mesenteric artery (SMA) are even more uncommon, with only six cases reported in the literature. We report a case of a 61-year old male patient who presented with hematemesis, haematochezia and haemorrhagic shock. The upper gastrointestinal endoscopy revealed an ulcerous lesion at the third portion of the duodenum, without achieving the haemostasis. The emergency laparotomy (suture of the lesion and gastro-entero-anastomosis) permitted temporary haemostasis. Computed tomography angiography identified the PDAA ruptured into the third portion of the duodenum and the SMA stenosis at its origin; a dense network of collateral vessels was present. The patient was successfully managed with coil embolization. Short and mid-term follow-up were without incidents.