Superior Mesenteric Artery Research Articles

Surgeon-modified fenestrated endovascular grafts and thoracoscope-assisted fixation for treatment of thoraco-abdominal aortic aneurysms.

Total endovascular technique with fenestrated endovascular graft might be hampered for the late dilatation of proximal landing zone, which may cause endografts migration. We describe a successful urgent hybrid procedure for extent III thoracoabdominal aortic aneurysm with aortic intramural hematoma. A 55-year-old female with thoracoabdominal aortic aneurysm was considered at high surgical risk and unfit for open repair due to multiple comorbidities. Therefore, a hybrid procedure of surgeon-modified fenestrated endovascular graft combined with thoracoscope-assisted Transaortic epicardial fixation of endograft was finally chosen and performed in the endovascular operating room. A 3-port technique was performed through a left video-assisted thoracoscopic approach. After the first tampering stent-graft was deployed, a double-needle suture was penetrated both the aortic wall and stent-graft to fixate it in the proximal descending aorta. Then the second endograft, which had been fenestrated on table, was introduced and oriented extracorporeally by rotating superior mesenteric artery and left renal artery fenestration radiopaque markers and deployed with perfect apposition between the fenestrations and target visceral artery. Each vessel was sequentially stented using Viabahn self-expandable stent to finish target vessel stenting. An Ankura cuff stent was deployed in the distal abdominal aortic artery. Surgeon-modified fenestrated endovascular graft combined with thoracoscope-assisted fixation may be an innovative and viable alternative for selected high-risk patients with extent III thoracoabdominal aortic aneurysm. A longer follow-up is needed to ascertain the success of this approach.

Hemodynamics in nutcracker syndrome: implications for diagnosis.

Nutcracker syndrome is a disease characterized by complex symptoms, making its diagnosis challenging and often delayed, often resulting in a painful experience for the patients. This study aimed to investigate the pathogenesis of nutcracker syndrome through the perspective of hemodynamics by simulating blood flow with varying compression degrees of the left renal vein. 3D patient-specific vascular models of the abdominal aorta, superior mesenteric artery and left renal vein were constructed based on CT images of patients suspected of having nutcracker syndrome. A hemodynamic simulation was then conducted using computational fluid dynamics to identify the correlation between alterations in hemodynamic parameters and varying degrees of compression. The study indicated the presence of anevident gradient in velocity distribution over the left renal vein with relatively high degrees of stenosis (α ≤ 50°), with maximum velocity in the central region of the stenosis. Additionally, when the compression degree of the left renal vein increases, the pressure distribution of the left renal vein presents an increasing number of gradient layers. Furthermore, the wall shear stress shows a correlation with the variation of blood flow velocity, i.e., the increase of wall shear stress correlates with the acceleration of the blood flow velocity. Using computational fluid dynamics as a non-invasive instrument to obtain the hemodynamic characteristics of nutcracker syndrome is feasible and could provide insights into the pathological mechanisms of thenutcracker syndrome supporting clinicians in diagnosis.

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

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. 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. 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. 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.

Association of Anthropometric and Sociodemographic Factors with Portal Vein Diameter as Assessed by Ultrasonography: A Cross Sectional Study

Background: Portal vein is the vessel formed by the confluence of superior mesenteric artery and splenic vein. Its diameter varies with sociodemographic and anthropometric factors. Objective: To determine association of the normal portal vein diameter with sociodemographic factors and anthropometric factors using ultrasonography. Methodology: Three hundreds and eighty-five patients of both genders were randomly selected. The study participants were examined in radiology department of the Mardan Medical Complex by using ultrasonography technique to examine portal vein diameter, height was measured using tape, weight through weighing scale and BMI through SPSS. Results: The mean portal vein diameter in the population of district Mardan was 10.41±1.65mm. Portal vein diameter of normal individuals had positive correlation with sociodemographic factors such as gender, age and anthropometric factors such height, weight and body mass index. Conclusions: There was positive correlation between age, height, weight and BMI, correlation was statistically significant.

Clinical and Molecular Characterization of a Novel Homozygous Frameshift Variant in AEBP1-Related Classical-like Ehlers Danlos Syndrome Type 2 with Comparison to Previously Reported Rare Cases.

Recently, an autosomal recessive subtype of connective tissue disorder within the spectrum of Ehlers-Danlos syndrome (EDS), named classical-like EDS type 2 (clEDS2), was identified. clEDS2 is associated with biallelic variants in the adipocyte enhancer binding protein 1 (AEBP1) gene, specifically, affecting its aortic carboxypeptidase-like protein (ACLP) isoform. We described the 15th patient (13th family) diagnosed with clEDS2. This patient presented with notable similarities in phenotype to the documented cases, along with additional characteristics such as significant prematurity and short stature. An EDS sequencing panel-based analysis revealed homozygous AEBP1: NM_001129.5:c.2923del, p.Ala975Profs*22 likely pathogenic variants, and maternally inherited heterozygous COL11A1: NM_001854.4:c.1160A>G, p.Lys387Arg variant of uncertain significance in our patient. Upon comprehensive review of all previously reported clEDS2 patients, our patient exhibited the following overlapping phenotypes, including cutaneous features: hyperextensibility, atrophic scars/delayed wound healing (100%), easy bruising (100%), excessive skin (93%); skeletal features: generalized joint hypermobility (93%), pes planus (93%), dislocation/subluxation (93%); and cardiovascular features (86%). Our patient did not display symptoms of the critical complications reported in a few individuals, including superior mesenteric artery aneurysms and ruptures, aortic root aneurysm/dissection, spontaneous pneumothoraxes, and bowel ruptures. Together, this case expands the genetic and clinical phenotypic spectrum of AEBP1-related clEDS2.

Angiotensinogen as a Therapeutic Target for Cardiovascular and Metabolic Diseases.

AGT (angiotensinogen) is the unique precursor for the generation of all the peptides of the renin-angiotensin system, but it has received relatively scant attention compared to many other renin-angiotensin system components. Focus on AGT has increased recently, particularly with the evolution of drugs to target the synthesis of the protein. AGT is a noninhibitory serpin that has several conserved domains in addition to the angiotensin II sequences at the N terminus. Increased study is needed on the structure-function relationship to resolve many unknowns regarding AGT metabolism. Constitutive whole-body genetic deletion of Agt in mice leads to multiple developmental defects creating a challenge to use these mice for mechanistic studies. This has been overcome by creating Agt-floxed mice to enable the development of cell-specific deficiencies that have provided considerable insight into a range of cardiovascular and associated diseases. This has been augmented by the recent development of pharmacological approaches targeting hepatocytes in humans to promote protracted inhibition of AGT synthesis. Genetic deletion or pharmacological inhibition of Agt has been demonstrated to be beneficial in a spectrum of diseases experimentally, including hypertension, atherosclerosis, aortic and superior mesenteric artery aneurysms, myocardial dysfunction, and hepatic steatosis. This review summarizes the findings of recent studies utilizing AGT manipulation as a therapeutic approach.

Superior mesenteric artery syndrome in oncology: Report of two cases and review of the literature

A rare cause of abdominal pain is the superior mesenteric artery syndrome (SMAS), characterized by an extrinsic compression of the third portion of the duodenum by the superior mesenteric artery. It occurs in the context of rapid weight loss, because of the decrease of intra-abdominal fat causing a reduction in the exit angle of this important vascular structure. Cancer patients frequently present with weight loss, often severe, making them a population at risk of presenting this syndrome. Because symptoms are vague and could be secondary to oncologic treatments, the diagnosis of SMAS is often overlooked. We present two cases of oncology patients evaluated in the National Cancer Institute in Chile who presented with symptoms suggestive of SMAS, weight loss greater than 5 kg in a short period of time associated with abdominal pain and vomiting. Both cases were confirmed by images [computed tomography (CT) scan] and treated with nutritional support only. We present both cases along with a brief review of the literature on this rare syndrome, which is usually a diagnostic challenge.

Anesthesia experience in an adult Silver-Russell syndrome: a case report

BackgroundThere are no reports of anesthesia use in adult patients with Silver-Russell syndrome (SRS). Here, we report our experience with anesthesia in an adult patient with SRS complicated by chronic respiratory failure.Case presentationA 33-year-old woman was clinically diagnosed with SRS. She had severe chronic respiratory failure, complicated by superior mesenteric artery syndrome. Percutaneous gastrostomy was scheduled for nutritional management under epidural anesthesia; however, soon after esophagogastroduodenoscopy was started, she lost consciousness and spontaneous respiration. The patient was urgently intubated and converted to general anesthesia. The end-tidal carbon dioxide tension was > 90 mmHg at intubation.ConclusionsAdult SRS patients with chronic respiratory failure have a risk of CO2 narcosis. SRS also requires preparation for difficult airway management during the perioperative period.

Autosomal Recessive Leber Hereditary Optic Neuropathy Triggered by Superior Mesenteric Artery Syndrome.

Autosomal Recessive Leber Hereditary Optic Neuropathy Triggered by Superior Mesenteric Artery Syndrome.

Gastrointestinal bleeding risk factors in type A aortic dissection post-aortic arch replacement.

Gastrointestinal bleeding (GIB) is a notable complication in patients diagnosed with aortic dissection (AD). We evaluated the outcomes and identified the risk factors associated with GIB in patients with AD. A retrospective case-control study was conducted on patients diagnosed with type A aortic dissection (TAAD) who underwent total aortic arch replacement (TAAR) at our institution from July 2021 to July 2023. Comprehensive clinical data, laboratory findings, and imaging results were meticulously gathered and analyzed to identify potential risk factors linked to GIB in this patient cohort. Of the 198 AD patients who underwent TAAR, 38 (19.2%) developed postoperative GIB (GIB group), with a median interval of 7 days between surgery and bleeding onset. The GIB group exhibited significantly higher mortality (26.3% vs. 3.1%, P<0.001), prolonged intensive care unit (ICU) stay {15 [interquartile range (IQR), 8-25] vs. 7 (IQR, 5-12) days, P<0.001}, and extended duration of ventilation [168 (IQR, 120-372) vs. 71 (IQR, 34-148) hours, P<0.001] compared to the control group (n=160, 80.8%). Logistic regression analysis identified age >54 years [odds ratio (OR): 3.529], intraoperative red blood cell (RBC) transfusion >600 mL (OR: 3.865), and concomitant celiac trunk and superior mesenteric artery (SMA) hypoperfusion (OR: 15.974) as independent risk factors for GIB in AD patients. GIB subsequent to TAAR in AD patients is linked to adverse prognosis. Factors such as advanced age, extensive intraoperative transfusion, and gastrointestinal (GI) perfusion abnormalities may heighten the risk of GIB in this patient population.

In-stent Restenosis After Stenting for Superior Mesenteric Artery Dissection Is Associated With Stent Landing Zone: From Clinical Prediction to Hemodynamic Mechanisms.

To identify risk factors for in-stent restenosis (ISR) in patients undergoing stent placement for superior mesenteric artery dissection (SMAD) and to determine the hemodynamic mechanism underlying ISR. For this retrospective study, patients with SMAD who had ISR after stent placement were included in the ISR group, and age- and sex-matched patients with SMAD who did not experience ISR after stent placement were included in the control group. Clinical, imaging, and hemodynamic data were assessed. Multivariable regression was used to identify independent ISR risk factors. Structural and fluid dynamics simulations were applied to determine the hemodynamic mechanism underlying the occurrence of ISR. The study population included 26 patients with ISR and 26 control patients. Multivariate analysis demonstrated that stent-to-vascular (S/V) ratio (odds ratio [OR], 1.14; 95% confidence interval [CI]: 1.00-1.29; p=0.045), stent proximal position >10 mm away from the SMA root (OR, 108.67; 95% CI: 3.09-3816.42; p=0.010), and high oscillatory shear index (OSI) area (OR, 1.25; 95% CI: 1.02-1.52; p=0.029) were predictors of ISR. In structural and fluid dynamics simulations, a stent proximal position near the abdominal aorta (AA) or entering into the AA reduced the contact area between the proximal struts of the stent and the vascular wall, and alleviated the distal lumen overdilation. The S/V ratio, stent proximal position away from the SMA root (>10 mm), and high OSI area are independent risk factors for ISR in patients with SMAD undergoing stent placement. Deploying the proximal end of the stent near the AA or entering into the AA appears to improve the hemodynamic environment in the SMA lumen and ultimately reduce the risk of ISR. In-stent restenosis is an uncommon but potentially catastrophic complication after stent placement for the management of superior mesenteric artery dissection. This study identified risk factors for in-stent restenosis and demonstrated that, as long as the stent can fully cover the dissection range, deploying the proximal end of the stent near the abdominal aorta or less entering into the abdominal aorta may reduce the risk of in-stent restenosis in this patient population.

SEVERE ACUTE PANCREATITIS REVEALING EXTENSIVE AORTIC DISSECTION: A CASE REPORT AND LITERATURE REVIEW

Severe acute pancreatitis is a frequent reason for hospitalization in the intensive care unit. Biliary and alcoholic etiologies are the most frequent. Vascular etiology, particularly ischemic etiology, is rare. Its often-serious consequences raise the question of how to proceed: should surgical treatment be provided, or should medical care be delayed? This study reports the case of an 87-year-old patient, known to be hypertensive, admitted to the emergency department of the Oued Eddahab military hospital with excruciating epigastric abdominal pain. Investigations revealed severe acute pancreatitis of ischemic origin following thoracoabdominal aortic dissection extending to the superior mesenteric artery. A review of the literature revealed only 15 similar cases of acute pancreatitis of ischemic origin associated with aortic dissection. This underlines the rarity of this situation, and the absence of standardized recommendations for the management of this exceptional situation, which presents the clinician with the dilemma of whether to opt for surgical or medical management. This case demonstrated the exceptional role of medical imaging in the context of severe acute pancreatitis, in terms of diagnosis, prognosis and etiology. It also highlighted the importance of an individualized approach based on multidisciplinary consultation, given the absence of recommendations and the paucity of literature.

Nutcracker syndrome in childhood

Nutcracker phenomenon (NP) is defined as the compression of the left renal vein, often occurring between the aorta and the superior mesenteric artery (SMA). Patients with symptoms associated with the Nutcracker anatomy are called “Nutcracker syndrome” (NCS). Renal vein compression results in venous congestion, outlet obstruction, and increased pressure in the left renal vein. The clinical manifestations of NCS in children vary widely depending on the severity of compression. It can range from being asymptomatic to presenting with intermittent or persistent micro or macrohematuria, orthostatic proteinuria, renovascular hypertension, abdominal pain, left-sided flank pain, dysmenorrhea, pain in the testicles or scrotum, and left varicocele. Hematuria, proteinuria, and flank pain are prevalent symptoms. The anatomical and physiological degree of compression of the left renal vein can be diagnosed through Doppler ultrasound (DUS), computer tomography (CT) scan, or magnetic resonance imaging (MRI). In cases with mild symptoms, conservative treatment is an appropriate option, and ACE inhibitors can be used for patients with proteinuria. In more severe cases where conservative approaches and medical treatment fail to yield satisfactory results, endovascular, laparoscopic, or open surgical interventions are employed.

Biomarkers and predictors of postoperative necrotizing enterocolitis in neonates with duct-dependent congenital heart defects undergoing cardiac surgery: a cohort study

The development of necrotizing enterocolitis (NEC) in neonates with duct-dependent congenital heart defects (CHD) who underwent cardiac surgery is accompanied by high mortality. Analysis of predictors is necessary for understanding the pathophysiology of NEC and development of approaches for prevention to achieve favorable outcomes of cardiac surgery. The purpose of the study was to develop a prognostic model for predicting the development of NEC after cardiac surgery in neonates with duct-dependent CHD. Methods. A prognostic cohort study was performed that included full-term neonates with duct-dependent CHD who underwent cardiac surgery at the Almazov National Medical Research Center from January 2021 to September 2023. The outcome was the development/absence of stage IB-III NEC in the postoperative period. Biomarkers of NEC (intestinal fatty acid binding protein (i-FABP, ng/ml), claudin-3 (CLDN3, ng/ml), calprotectin (CALPR, ng/ml), ischemia modified albumin (IMA, ng/ml), vascular endothelial growth factor A (VEGF A, pg/ml)) were measured by ELISA in the blood serum before cardiac surgery and 12-14 hours after surgery. We also analyzed clinical characteristics of neonates, C-reactive protein levels, complete blood count, abdominal ultrasound, ejection fraction (EF, Teicholtz) in the preoperative and postoperative periods, surgical parameters, P(v-a)CO2/C(a-v)O2 upon arrival from the operating room, vasoactive inotropic score (VIS) and arterial blood lactate levels in the first 24 hours after surgery. The association between predictors and the development of NEC after cardiac surgery was assessed using univariate and multivariate logistic regression analysis. Internal validation of the model was performed using 10-fold cross-validation. Results. During the observation period, 187 neonates underwent surgical treatment of duct-dependent CHD, of which 32 children developed stage IB-III NEC in the postoperative period (17.1%), two neonates required surgical treatment of NEC (6.3%). After meeting the non-inclusion and exclusion criteria, two groups of patients were formed: a main group (30 neonates who developed stages IB-III NEC in the postoperative period, of which stage III NEC was in one neonate) and a comparison group (40 neonates without NEC). Groups were comparable by types of CHD. Predictors associated with NEC (univariate analysis): intrauterine growth retardation (IUGR), formula feeding before surgery, high levels of IMA before on the first postoperative day (POD), procedures performed before surgery (Rashkind procedure/valvuloplasty/stenting), lower EF in in the early postoperative period, a higher maximum level of VIS in the first 24 hours after surgery, as well as a higher level of IR in the superior mesenteric artery (SMA) and thickening of the intestinal wall on the first postoperative day (POD) Independent preoperative predictors of NEC (AUC of model 0.885, specificity 0.867): IUGR (OR 32.2 (1.4-730.3), p=0.029), formula feeding (OR 12.6 (2.6-60.2), p=0.002), IMA level before surgery (OR 1.03 (1.01-1.04), p=0.004), CLDN3 level before surgery (OR 0.5 (0.3-0.9), p=0.013). Independent early postoperative predictors of NEC: IMA level on 12-14 hour after surgery (OR 1.02 (1.01-1.03), p=0.030), P(v-a)CO2/C(a-v)O2 immediately after surgery (OR 2.3 (1.2-4.4), p=0.008), IR&gt;0.93 in SMA (OR 7.2 (1.6-32.4), p=0.011) and thickness of intestinal wall by ultrasound on POD 1 (OR 4.9 (1.3-19.2), p=0.021). Adding of VEGF A level (12-14 hour after surgery, negatively associated with NEC) to the model increased the specificity, but the predictor was not significant. AUC of postoperative model 0.862, specificity 0.800. The final model included preoperative (IUGR, formula feeding) and postoperative predictors (IMA, P(v-a)CO2/C(a-v)O2, IR of SMA&gt;0.93, intestinal wall thickness), AUC=0.921, specificity 0.83. Conclusion. The identified predictors indirectly indicate the role of hypoxia in the pathophysiology of NEC in term neonates with duct-dependent CHD. Breast milk feeding/mixed feeding in the preoperative period may help reduce the risk of NEC in the postoperative period. Low levels of CLDN3 before surgery were associated with the development of NEC, but the interpretation of the result is controversial.

Strong Procedure for Superior Mesenteric Artery Syndrome in Children: A Case Report

Superior mesenteric artery syndrome (SMAS) or Wilkie syndrome is a rare anomaly resulting from extrinsic compression of the third duodenal segment by the superior mesenteric artery (SMA) anteriorly and the abdominal aorta posteriorly. Clinically, SMAS is characterized by acute or chronic upper obstruction associated with intermittent abdominal pain. Abdominal computed tomography is the key examination for establishing the diagnosis. Although initial management is medical, surgery is required if this fails. We report the case of a 12-year-old girl admitted for acute occlusive syndrome associated with abdominal pain, in whom the diagnosis of SMAS was retained. Treatment consisted of Strong's surgical technique after failure of medical treatment with good evolution. Our case reports that in cases of SMAS where medical treatment is ineffective, less invasive surgical options such as Strong's technique may be considered to facilitate rapid recovery while minimizing the risk of complications associated with more complex procedures involving bowel resection and anastomosis.

Abstract 2393: Development of a novel implantable drug-eluting product for the local treatment of pancreatic adenocarcinoma

Abstract Background Local control of non-metastatic pancreatic ductal adenocarcinoma (PDAC) remains a major challenge. Therapies with reduced systemic toxicity are needed as intravenous (IV) infusions are limited by patient tolerance with only small amounts reaching the tumor. PanTher created PTM-101, a novel absorbable drug formulation containing paclitaxel, designed to be locally applied via minimally invasive surgery to provide chemotherapy precisely to the peritumoral area in PDAC. Methods A study was conducted using 3 cadaveric abdomens to evaluate surgical feasibility of delivering PTM-101 via laparoscopy. Prior to insertion of PTM-101 into the peritoneum, the surgeons prepared each product by suturing a 3-0 Vicryl SH (Ethicon) at four evenly spaced locations around the edge of the flat circular product. A periumbilical 10mm Hasson port was placed to insufflate the abdomen, followed by placement of 3 additional working ports (5mm). The liver capsule was carefully surveyed to exclude metastatic disease. The surgeons opened a window into the lesser sac through the greater omentum, lifting the stomach up from the transverse colon to expose the pancreas. PTM-101 (a 1mm thick and 6cm diameter film) was rolled into a tubular shape, inserted through the cannula, and affixed to the peri-pancreatic fat with existing vicryl stitches. Results The estimated total operative time from placement of the first trocar to removal of all equipment was 45 minutes, for the 3 procedures. The operations included 25 minutes for entry, port placement, exposure of the simulated pancreatic tumor location and 20 minutes to place and suture PTM-101. PTM-101 was easy to fit through the cannula and was sutured without difficulty to the peri-pancreatic fat that surrounds the capsule of the pancreas. To simulate a tumor with hepatic artery involvement, the implant was sutured towards the hepatoduodenal ligament in one specimen, near the area of the gastroduodenal artery takeoff, proper hepatic artery, and proximal portal vein. PTM-101 covered the entire head/neck area of the simulated tumor locations without requiring disruption of the tumor area or dissection of the tunnel under the pancreatic neck. Conclusion PTM-101 is flexible and conforms easily to the underlying topography, both in a concave (i.e., with the tumor intact) and convex (i.e., after resection) scenario. Although human anatomy does not allow for PTM-101 to completely wrap around the pancreas, the size and flexibility of the product enables it to “drape” over the edges covering areas near the superior mesenteric vein and artery (SMV/SMA). This placement could hypothetically increase the amount of drug reaching the area behind the pancreas to target tumors which abut or encase the mesoportal vasculature. A decrease in the tumor-vessel interface could downsize pancreatic tumors, with the goal of increasing resection rates and post-resection local control. Citation Format: Margaret Lashof-Sullivan, Leslie S. Sloan, Michael P. Kim, Laura Indolfi, Ching-Wei D. Tzeng. Development of a novel implantable drug-eluting product for the local treatment of pancreatic adenocarcinoma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 2393.

Robotic Pancreaticoduodenectomy with 'SMA-First Approach (Posterior and Right Medial)' and 'Triangle Operation'.

Notable improvements in pancreatic cancer surgery have been due to utilization of the superior mesenteric artery (SMA)-first approach1 and triangle operation (clearance of triangle tissue between origin of SMA and celiac artery).2 The SMA-first approach was originally defined to assess resectability before taking the irreversible surgical steps. However, in the present era, resectability is judged by the preoperative radiology, and the benefit of the SMA-first approach is by improving the R0 resection rate and reducing blood loss. The basic principle is to identify the SMA at its origin and in the distal part, to guide the plane of uncinate dissection. This video demonstrates the combination of the posterior and right medial SMA-first approach along with triangle clearance during robotic pancreaticoduodenectomy (RPD). The technique consisted of early dissection of SMA from the posterior aspect, by performing a Kocher maneuver using the 'posterior SMA-first approach'. The origin of the celiac artery, along with the SMA, was defined early in the surgery. During uncinate process dissection, the 'right/medial uncinate approach' was used to approach the SMA. 'Level 3 systematic mesopancreatic dissection' was performed along the SMA,3 culminating in the 'triangle operation'.2 RESULTS: The procedure was performed within 600min, with a blood loss of 150mL and no intraoperative or postoperative complications. The final histopathology report showed a moderately differentiated adenocarcinoma (pT2, pN2), with all resection margins free. The standardized technique of the SMA-first approach and triangle clearance during RPD is demonstrated in the video. Prospective studies should further evaluate the benefits of this procedure.

Efficacy and safety analysis of AcoStream thrombus aspiration device in the treatment of acute superior mesenteric artery embolism.

Acute superior mesenteric artery embolism is a life-threatening disease caused by the abrupt interruption of mesenteric blood circulation, and the prognosis is very poor. Several studies have confirmed the efficacy and safety of percutaneous mechanical thrombectomy in acute superior mesenteric artery embolism, however, there are currently no literature reports on the latest percutaneous mechanical thrombectomy device-AcoStream™. In the present report, we summarize a series of cases and share our surgical experiences. The clinical data of 10 patients (six men and four women, mean age 77.6 ± 7.4years) with acute superior mesenteric artery embolism treated by AcoStream™ in our center from December 2022 to December 2023 were retrospectively analyzed. Based on the literature, we summarized the diagnosis, therapy, and surgical experience of acute superior mesenteric artery embolism. Percutaneous mechanical thrombectomy was performed for all the patients. The success rate of surgery reached 100% and no perioperative complications occurred. Abdominal pain was significantly relieved and the abdominal signs gradually disappeared in eight patients, while the other two patients still complained of abdominal pain during hospitalization, and eventually, they underwent resection of necrotic bowel. All the patients' symptoms were significantly relieved and they were smoothly discharged from the hospital. As shown in the present study, percutaneous mechanical thrombectomy using AcoStream™ is minimally invasive, safe, and efficient in the initial stage of acute superior mesenteric artery embolism. We believe that percutaneous mechanical thrombectomy can be a promising alternative in selected cases.

Literature Survey for In-Vivo Reynolds and Womersley Numbers of Various Arteries and Implications for Compliant In-Vitro Modelling

PurposeIn-vitro modelling can be used to investigate haemodynamics of arterial geometry and stent implants. However, in-vitro model fidelity relies on precise matching of in-vivo conditions. In pulsatile flow, velocity distribution and wall shear stress depend on compliance, and the Reynolds and Womersley numbers. However, matching such values may lead to unachievable tolerances in phantom fabrication.MethodsPublished Reynolds and Womersley numbers for 14 major arteries in the human body were determined via a literature search. Preference was given to in-vivo publications but in-vitro and in-silico values were presented when in-vivo values were not found. Subsequently ascending aorta and carotid artery case studies were presented to highlight the limitations dynamic matching would apply to phantom fabrication.ResultsSeven studies reported the in-vivo Reynolds and Womersley numbers for the aorta and two for the carotid artery. However, only one study each reported in-vivo numbers for the remaining ten arteries. No in-vivo data could be found for the femoral, superior mesenteric and renal arteries. Thus, information derived in-vitro and in-silico were provided instead. The ascending aorta and carotid artery models required scaling to 1.5× and 3× life-scale, respectively, to achieve dimensional tolerance restrictions. Modelling the ascending aorta with the comparatively high viscosity water/glycerine solution will lead to high pump power demands. However, all the working fluids considered could be dynamically matched with low pump demand for the carotid model.ConclusionThis paper compiles available human haemodynamic information, and highlights the paucity of information for some arteries. It also provides a method for optimal in-vitro experimental configuration.

A radio-anatomical study of median arcuate ligament syndrome: unveiling the morphology and morphometry of median arcuate ligament, celiac trunk, and superior mesenteric artery.

In the context of medical literature, a significant lacuna exists in understanding median arcuate ligament syndrome (MALS). While clinical aspects are well documented, literature lacks a robust exploration of the anatomical relationship between the celiac trunk and the median arcuate ligament (MAL). Morphometric parameters, including the vertebral level of MAL origin, MAL thickness, celiac trunk (CeT) origin level, diameter, and distances between CeT/Superior Mesenteric Artery (SMA) and the MAL center were observed on 250 CT angiograms. Cadavers (n = 11) were dissected to examine the same parameters and histo-morphological examination of MAL tissue was done. Radiological findings established average MAL thickness of 7.79 ± 2.58mm. The celiac trunk typically originated at T12. The average distance between the celiac trunk and the MAL center was 1.32 ± 2.04mm. The angle of the celiac trunk to the abdominal aorta was primarily obtuse. The average celiac trunk diameter was 5.53 ± 1.33mm. Histological examinations revealed a diverse MAL composition, indicating variable mechanical properties. This study provides comprehensive morphometric data on the anatomical relationship between the MAL and the celiac trunk. In contrast to available literature which says the average MAL thickness of > 4mm is an indicator of increased thickness, we observed much higher average thickness in the studied population. The findings contribute to a better understanding of normal anatomical variations which can serve as reference values for accurate radiological diagnosis of MALS. The histological examination revealed the heterogeneous nature of the MAL tissue composition, suggesting variable mechanical properties and functions in different regions.