No difference in postprandial mesenteric blood flow between healthy younger and elderly individuals.

We recently used phase-contrast magnetic resonance imaging (PC-MRI) to demonstrate an attenuated postprandial blood flow response in the superior mesenteric artery (SMA) in patients with Parkinson's disease compared to age- and sex-matched healthy controls. Since both groups showed substantial inter-individual variations, we extended the cohort of controls with a group of young individuals to investigate possible age-related effects. Seventeen healthy young subjects aged < 30 years and 17 elderly subjects aged > 50 years underwent serial PC-MRI to measure the postprandial blood flow response in the SMA after ingestion of a standardized liquid test meal (∼400 kcal). Postprandial blood flow dynamics in SMA did not differ between young and elderly subjects. A noticeable inter-individual variation in postprandial intestinal blood flow increase was found, and approximately 30% of the variation could be explained by the preprandial blood flow. Regardless of age, some subjects showed a remarkable transient SMA blood flow increase immediately after meal intake. This study provides tentative evidence that postprandial blood flow dynamics in SMA in healthy young and elderly subjects do not substantially differ, indicating that age is without impact on vascular response in SMA as an indicator for regulation of mesenteric perfusion in response to food intake.

Treatment outcomes in patients with acute thromboembolic occlusion of the superior mesenteric artery.

OBJECTIVES: The goals of this study were to investigate the treatment outcomes of acute thromboembolic occlusion of the superior mesenteric artery (ATOS) and identify prognostic factors after treatment. METHODS: The clinical data of 62 patients with ATOS between 2013 and 2021 were retrospectively reviewed. Patients were stratified by the treatment strategy, complications and mortality were compared in different group. RESULTS: Sixty-two consecutive patients were identified with ATOS. The median patient age was 69 years (interquartile range 58-79 years). Endovascular therapy was initiated in 21 patients, and 4 patients received conservative treatment. Open surgery was performed first in the remaining 37 patients. The technical success rates of the endovascular first group and open surgery group were 90.5% and 97.3%, respectively. One patient in the conservative treatment group had progression of ischemia to extensive bowel necrosis. There was no difference in 30-day mortality between these groups. Predictors of 30-day mortality included initial neutrophil count > 12* 103/dL, age over 60 years old and history of chronic renal insufficiency. CONCLUSIONS: Endovascular treatment or conservative treatment may be adopted in selected patients who do not exhibit signs and symptoms of bowel necrosis, and close monitoring for bowel necrosis is important. The increase in preoperative neutrophil count, age over 60 years old and history of chronic renal insufficiency were poor prognostic factors.

Spontaneous isolated gastric intramural hematoma combined with spontaneous superior mesenteric artery intermural hematoma: a rare case.

BACKGROUND: Gastric intramural hematoma is a rare disease. Here we report a case of spontaneous isolated gastric intramural hematoma combined with spontaneous superior mesenteric artery intermural hematoma. CASE PRESENTATION: A 75-years-old man was admitted to our department with complaints of abdominal pain. He underwent a whole abdominal computed tomography (CT) scan in the emergency department, which showed extensive thickening of the gastric wall in the gastric body and sinus region with enlarged surrounding lymph nodes, localized thickening of the intestinal wall in the transverse colon, localized indistinct demarcation between the stomach and transverse colon, and a small amount of fluid accumulation in the abdominal cavity. Immediately afterwards, he was admitted to our department, and then we arranged a computed tomography with intravenously administered contrast agent showed a spontaneous isolated gastric intramural hematoma combined with spontaneous superior mesenteric artery intermural hematoma. Therefore, we treated him with anticoagulation and conservative observation. During his stay in the hospital, he was given low-molecular heparin by subcutaneous injection for anticoagulation therapy, and after discharge, he was given oral anticoagulation therapy with rivaroxaban. At the follow-up of more than 4 months, most of the intramural hematoma was absorbed and became significantly smaller, and the intermural hematoma of the superior mesenteric artery was basically absorbed, which also confirmed that the intramural mass was an intramural hematoma. CONCLUSION: A gastric intramural hematoma should be considered, when an intra-abdominal mass was found to be attached to the gastric wall. Proper recognition of gastric intramural hematoma can reduce the misdiagnosis rate of confusion with gastric cancer.

Jejunal vein tributary analysis and intraoperative clamp testing in avoiding congestion after pancreatoduodenectomy.

PURPOSE: Although venous drainage of the jejunal loop may be maintained after sacrifice of jejunal vein tributaries during pancreatoduodenectomy, risk of severe jejunal mesenteric congestion following division of these tributaries can be difficult to predict. This study considered how best to predict safety of jejunal vein tributary dissection. METHODS: Preoperative imaging findings and results of intraoperative clamp tests of jejunal vein tributaries during pancreatoduodenectomy were analyzed in 121 patients with hepatobiliary and pancreatic disease to determine whether this information adequately predicted safety of resecting superior mesenteric vein branches. RESULTS: Jejunal vein tributaries caudal to the inferior border of the pancreatic uncinate process tended to be fewer when tributaries cranial to this landmark were more numerous. Tributaries cranial to the border drained a relatively wide expanse of jejunal artery territory in the jejunal mesentery. The territory of jejunal tributaries cranial to the inferior border of the pancreas did not vary according to course of the first jejunal vein branch relative to the superior mesenteric artery. One patient among 30 (3%) who underwent intraoperative clamp tests of tributaries cranial to the border showed severe congestion in relation to a venous tributary coursing ventrally to the superior mesenteric artery. CONCLUSION: Jejunal venous tributaries drained an extensive portion of jejunal arterial territory, but tributaries located cranially to the inferior border of the pancreas could be sacrificed without congestion in nearly all patients. Intraoperative clamp testing of these tributaries can identify patients whose jejunal veins must be preserved to avoid congestion.

Multimodal Study of the Superior Mesenteric Artery Wall.

BACKGROUND: To quantitatively analyze histological and fiber structure of the superior mesenteric artery (SMA) wall and to further explore the possible relationship between the architecture and histology changes of vessel wall and the occurrence of related diseases. METHODS: Histological and fiber structure analysis were performed on SMA specimens obtained from 22 cadavers. The SMA specimens were divided into initial, curved, and distal segments, and each segment was separated into the anterior and posterior walls. RESULTS: From the initial to the curved to the distal segment, the ratio of elastin decreased (31.4% ± 6.0%, 21.1% ± 5.8%, 18.6% ± 4.7%, respectively; P < 0.001), whereas the ratio of smooth muscle actin (24.5% ± 8.7%, 30.5% ± 6.8%, 36.1% ± 7.3%, respectively; P < 0.001) increased. Elastic fiber longitudinal amplitude of angular undulation was highest in the initial segment [7° (3.25°, 15°)] and lowest in the curved segment [2° (1°, 5°)]. In SMA curved segment, the anterior wall, when compared with the posterior wall, demonstrated a lower ratio of elastin (19.0% ± 5.8% vs. 23.3% ± 5.0%; P = 0.010) and collagen (41.4% ± 12.3% vs. 49.0% ± 10.2%; P = 0.032), a lower elastic fiber longitudinal amplitude of angular undulation [1° (1°, 5°) vs. 3° (2°, 5.25°); P = 0.013], a lower average fiber diameter (8.06 ± 0.36 pixels vs. 8.45 ± 0.50 pixels; P = 0.005), and a lower average segment length (17.96 ± 1.59 pixels vs. 20.05 ± 2.33 pixels; P = 0.001). CONCLUSIONS: SMA wall structure varies along the circumferential and axial directions, the presence of dense undulated elastic fiber protects the SMA initial segment of from dissection and aneurysm, but highly cross-linked collagen fiber here increases the likelihood of plaque formation. In the anterior wall of the curved segment, lower elastin and collagen content, lower elastic fiber undulation, and higher degree of collagen fiber cross-linking leads to the occurrence of SMA dissection and aneurysm. In the distal segment, high levels of vascular smooth muscle cells and bundles of long collagen fiber offer protection against the development of SMA-related diseases.

Superior mesenteric artery revisited using magnetic resonance angiography.

PURPOSE: We aimed to examine the superior mesenteric artery in detail by magnetic resonance angiography to provide an alternative to other imaging methods, to reduce the exposure time of patients and physicians to X-rays and the time spent in catheter angiography, to determine the variations, positions, and locations of the celiac trunk, and to provide detailed information for surgeons and interventional radiologists using this method. METHODS: The procedures were approved by the Kocaeli University Medical School Non-Interventional Clinical Research Ethics Committee (10.04.2023, approval number: 2021/51). MR angiography images of 185 patients with abdominal imaging in PACS (Picture Archiving Communication Systems) were retrospectively registered. The level of origin of the superior mesenteric artery according to the vertebral column, angle of origin, distance between the superior mesenteric artery and branches of the abdominal aorta, and branching pattern of the superior mesenteric artery were evaluated. Parameters were evaluated according to gender and age using SPSS version 25. RESULTS: The distance between superior mesenteric artery-inferior mesenteric artery and superior mesenteric artery-aortic bifurcation in males was higher than in females, and the difference was statistically significant. In females and the whole study group, a low, positive and significant relationship was found between age and superior mesenteric artery-sagittal angle. The most common origin site for the superior mesenteric artery, according to the vertebral column was found to be at L1 middle for males and L1 upper for females. The most common superior mesenteric artery branching pattern was classical type in both genders. CONCLUSION: Individual evaluation of the superior mesenteric artery could reduce the risks during surgical interventions, considering the relationship of the superior mesenteric artery, especially with distally located vessels, and the gender differences for the angle of origin. Furthermore, considering that interventional radiologists choose the catheter according to the angle of origin of the artery during catheter angiography procedures, individual evaluation of patients taking into account gender and age is of utmost importance.

Dynamic ultrasonography for optimizing treatment position in superior mesenteric artery syndrome: Two case reports and review of literature.

BACKGROUND: Superior mesenteric artery (SMA) syndrome is a rare cause of duodenal obstruction by extrinsic compression between the SMA and the aorta (SMA-Ao). Although the left lateral recumbent position is considered effective in the treatment of SMA syndrome, individual variations in the optimal patient position have been noted. In this report, we present two elderly cases of SMA syndrome that exhibited rapid recovery due to ultrasonographic dynamic evaluation of the optimal position for each patient. CASE SUMMARY: Case 1: A 90-year-old man with nausea and vomiting. Following diagnosis of SMA syndrome by computed tomography (CT), ultrasonography (US) revealed the SMA-Ao distance in the supine position (4 mm), which slightly improved in the lateral position (5.7-7.0 mm) without the passage of duodenal contents. However, in the sitting position, the SMA-Ao distance was increased to 15 mm accompanied by improved content passage. Additionally, US indicated enhanced passage upon abdominal massage on the right side. By day 2, the patient could eat comfortably with the optimal position and massage. Case 2: An 87-year-old woman with vomiting. After the diagnosis of SMA syndrome and aspiration pneumonia by CT, dynamic US confirmed the optimal position (SMA-Ao distance was improved to 7 mm in forward-bent position, whereas it remained at 5 mm in the supine position). By day 7 when her pneumonia recovered, she could eat with the optimal position. CONCLUSION: The optimal position for SMA syndrome varies among individuals. Dynamic US appears to be a valuable tool in improving patient outcomes.

Deep learning algorithm applied to plain CT images to identify superior mesenteric artery abnormalities.

OBJECTIVES: Atypical presentations, lack of biomarkers, and low sensitivity of plain CT can delay the diagnosis of superior mesenteric artery (SMA) abnormalities, resulting in poor clinical outcomes. Our study aims to develop a deep learning (DL) model for detecting SMA abnormalities in plain CT and evaluate its performance in comparison with a clinical model and radiologist assessment. MATERIALS AND METHODS: A total of 1048 patients comprised the internal (474 patients with SMA abnormalities, 474 controls) and external testing (50 patients with SMA abnormalities, 50 controls) cohorts. The internal cohort was divided into the training cohort (n = 776), validation cohort (n = 86), and internal testing cohort (n = 86). A total of 5 You Only Look Once version 8 (YOLOv8)-based DL submodels were developed, and the performance of the optimal submodel was compared with that of a clinical model and of experienced radiologists. RESULTS: Of the submodels, YOLOv8x had the best performance. The area under the curve (AUC) of the YOLOv8x submodel was higher than that of the clinical model (internal test set: 0.990 vs 0.878, P =.002; external test set: 0.967 vs 0.912, P =.140) and that of all radiologists (P <.001). The YOLOv8x submodel, when compared with radiologist assessment, demonstrated higher sensitivity (internal test set: 100.0 % vs 70.7 %, P =.002; external test set: 96.0 % vs 68.8 %, P <.001) and specificity (internal test set: 90.7 % vs 66.0 %, P =.025; external test set: = 88.0 % vs 66.0 %, P <.001). CONCLUSION: Using plain CT images, YOLOv8x was able to efficiently identify cases of SMA abnormalities. This could potentially improve early diagnosis accuracy and thus improve clinical outcomes.

Acute superior mesenteric artery syndrome complicated by severe gastric, pancreatic and renal ischaemia.

Superior mesenteric artery syndrome (SMAS) is a rare and potentially life-threatening cause of small bowel obstruction in which the superior mesenteric artery impinges on the third portion of the duodenum. SMAS is typically encountered in patients with low body fat and a history of rapid weight loss and is often diagnosed as a chronic or subacute condition. Here, we describe a case of a healthy adolescent boy without typical SMAS prodromal symptoms presenting with a severe, hyperacute proximal small bowel obstruction due to SMAS. Complications arising from massive gastric and duodenal distension, including gastric, pancreatic and renal ischaemia, necessitated emergent surgical intervention consisting of the duodenojejunostomy bypass with partial gastric resection. The patient recovered without significant lasting consequences.

[Surgical strategies and efficacy analysis for aortic dissection complicating intractable mesenteric artery ischemia].

Objective: To explore the surgical strategies and clinical efficacy for aortic dissection combined with refractory superior mesenteric artery (SMA) ischemia. Methods: This is a retrospective case series study. Clinical data of 24 patients with aortic dissection and refractory SMA ischemia admitted to the Department of Vascular Surgery, Zhongshan Hospital, Fudan University from August 2010 to August 2020 were retrospectively collected. Of the 24 patients, 21 were males and 3 were females, with an age of (50.3±9.9) years (range: 44 to 72 years).Among them, 9 cases were Stanford type A aortic dissection, and 15 cases were type B. All patients underwent CT angiography upon admission, and based on imaging characteristics, they were classified into three types. Type Ⅰ: severe stenosis/occlusion of the SMA true lumen only; Type Ⅱ: stenosis of the true lumens in the descending aorta and SMA (isolated type); Type Ⅲ: stenosis of the true lumens in the thoracoabdominal aorta and SMA (continuation type). Surgical procedures, complications, mortality, and reintervention rates were recorded. Results: Among the 24 patients, 17 (70.8%) were classified as Type Ⅰ, 4 (16.7%) as Type Ⅱ, and 3 (12.5%) as Type Ⅲ. Fourteen cases of Type Ⅰ underwent thoracic endovascular aortic repair combined with SMA stent implantation. Additionally, 3 Type Ⅰ and 1 Type Ⅱ patients underwent only SMA reconstruction (with one case of chronic TAAD treated with iliac artery-SMA bypass surgery). Moreover, 3 Type Ⅱ and 3 Type Ⅲ patients underwent descending aorta combined with SMA stent implantation. There were 5 patients (20.8%) who underwent small bowel resection, either in the same sitting or in a staged procedure. During hospitalization, 4 patients died, resulting in a mortality rate of 16.7%. Among these cases, two patients succumbed to severe intestinal ischemia resulting in multiple organ dysfunction syndrome. The follow-up duration was (46±9) months (range: 13 to 72 months). During the follow-up, 2 patients died, unrelated to intestinal ischemia. The 5-year freedom from reintervention survival rate was 86.1%, and the 5-year cumulative survival rate was 82.6%. Conclusions: Patients with aortic dissection and refractory SMA ischemia have a high perioperative mortality. However, implementing appropriate surgical strategies according to different clinical scenarios can reduce mortality and alleviate intestinal ischemia.

Use of selective visceral angiography in surgical strategy planning for celiac artery aneurysm in the celiacomesenteric trunk.

BACKGROUND: The celiacomesenteric trunk (CMT) is a common duct of the celiac artery (CA) and the superior mesenteric artery originating from the aorta, which is an uncommon anatomical variant of visceral artery circulation. Because of the variety of visceral circulation in those with CMT, the visceral circulation associated with each branch should be evaluated prior to surgical treatment of visceral artery aneurysm in the CMT. CASE PRESENTATION: A 64-year-old woman was diagnosed with a CA aneurysm in the CMT. Aneurysmectomy of the aneurysm was performed successfully. On preoperative selective visceral angiography, the CA was seen to bifurcate into the common hepatic and splenic artery. The left gastric artery was directly isolated from the aorta and perfused to the common hepatic and splenic artery through collateral circulation. These findings showed that celiac artery embolization is anatomically feasible, even in cases of celiac artery aneurysm rupture. CONCLUSIONS: Selective visceral angiography can contribute to surgical strategy planning for CA aneurysm with CMT.

Thrombosis of acute superior mesenteric artery in a patient with breast cancer receiving toremifene therapy: a case report and literature review.

It is widely recognized that cancer itself is related to increased risk of thromembolism. Venous thromboembolism is relatively common in breast cancer patients, but arterial thrombosis, especially acute superior mesenteric artery thrombosis (SMAT) associated with chemotherapy or endocrinotherapy, rarely occurs in breast cancer patients. There were few reports about acute SMAT in cancer patients who underwent chemotherapy, but no reports of acute SMAT caused by endocrine-therapy. We reported a 54-year-old patient with acute SMAT during toremifene treatment after breast cancer surgery. She underwent 4 cycles chemotherapy of TC regimen, then accepted toremifen endocrinotherapy because of positive estrogen receptor. She suffered from acute SMAT after 2 months toremifen treatment. Therefore, we consider that this case of acute SMAT may be a rare adverse event of toremifen. In view of the high risk and rarity of acute SMAT caused by toremifene, we suggest that except for venous thrombosis, arterial thrombosis in special position (ATSP) should be kept in mind during use of toremifene. Once a thrombotic event occurs, toremifene should be stopped immediately.

Familial visceral branch artery aneurysms in Loeys-Dietz syndrome.

Loeys-Dietz syndrome (LDS) is an autosomal dominant heritable disorder due to pathogenic variants in one of several genes involved in TGF-ß (transforming growth factor-beta) signalling. LDS is associated with aortic aneurysm and dissection. LDS may also lead to extra-aortic aneurysms, the majority of which occur in the head and neck vasculature. Visceral aneurysms are uncommon, and no cases of distal superior mesenteric artery (SMA) branch aneurysms in patients with LDS have been reported. Three related females with TGFBR1-related LDS developed distal SMA branch artery aneurysms involving the ileocolic and jejunal arteries. Endovascular or surgical intervention was performed in each. The presence and severity of arterial, craniofacial, and cutaneous features of LDS in these patients are variable. TGFBR1-related LDS may rarely lead to SMA branch artery aneurysms that can develop later in life. Surgical and endovascular procedures can successfully treat these aneurysms, but data to guide size thresholds and optimal treatment strategies are lacking.

Successful Endovascular Treatment of Calcified Superior Mesenteric Artery Complicated by Intramural Hematoma in Chronic Mesenteric Ischemia.

BACKGROUND Chronic mesenteric ischemia (CMI) is defined as ischemic symptoms caused by insufficient supply of blood to the gastrointestinal tract. Patients diagnosed with advanced symptomatic CMI should be treated subsequently, as the transition from CMI to acute mesenteric ischemia can be unpredictable. However, there is little information regarding the management of potential procedural complications during endovascular therapy (EVT) for CMI. CASE REPORT A 70-year-old man was admitted to our hospital with recurrent abdominal pain just after hemodialysis. The angiogram showed significant stenosis with heavy calcification in the proximal of the superior mesenteric artery (SMA), leading to the diagnosis of CMI. To alleviate the symptom, EVT for the stenotic lesion of the SMA was indicated. During the procedure, a cutting balloon was inflated to facilitate vessel expansion in the target lesion. As a result, intravascular ultrasound (IVUS) imaging revealed dissection into the media with extension into the medial space without reentry and demonstrated a semilunar intramural hematoma. We were able to contain the intramural hematoma by covering the whole dissection in the SMA with implantation of self-expandable stents. CONCLUSIONS This case highlights the potential of EVT for heavy calcification of the SMA complicated by dissection without reentry. Intramural hematoma was observed with IVUS examination. We were able to contain the hematoma by the implantation of self-expandable stents over the whole length of the SMA dissection under IVUS-guided EVT.

Open Management of an Asymptomatic 4.2 Cm Middle Colic Artery Aneurysm and Liteture Review.

BACKGROUND: Aneurysms of the middle colic artery (MCAA) and its branches are exceedingly rare accounting for <3% of total visceral aneurysms. Very few MCAA cases have been reported in the literature with only three cases accounting for a diameter >4 cm. METHOD: We describe the successful open repair with ligation of a 4.2 cm asymptomatic MCAA in a female patient through the gastrohepatic ligament taking meticulous caution to avoid injury of the pancreas. The postoperative period was uneventful and the patient was discharged from the hospital on the fifth postoperative day. At 1 month follow-up the postoperative computed tomographic angiography documented complete exclusion of the MCAA and absence of contrast agent in the sac both in the arterial and the venous phase. CONCLUSION: While the endovascular treatment is the first-line option for visceral aneurysms, the open approach is still reserved for certain cases of hostile anatomy, challenging location and large size. Our case highlights the irreplaceable role of open surgery and underlines the collaboration between surgical specialties.

Raising Systemic Blood Pressure to Delay Irreversible Intestinal Ischemia in a Swine Model of Proximal Superior Mesenteric ArteryOcclusion.

INTRODUCTION: Acute proximal superior mesenteric artery (SMA) occlusion is highly lethal, and adjuncts are needed to mitigate ischemic injury until definitive therapy. We hypothesized that raising mean arterial pressure (MAP) >90 mmHg with norepinephrine may delay irreversible bowel ischemia by increasing gastroduodenal artery (GDA) flow despite possible pressor-induced vasospasm. METHODS: 12 anesthetized swine underwent laparotomy, GDA flow probe placement, and proximal SMA exposure and clamping. Animals were randomized between conventional therapy (CT) versus targeted MAP >90 mmHg (MAP push; MP) where norepinephrine was titrated after 45 min of SMA occlusion. Animals were followed until bowel death or 4 h. Kaplan-Meier bowel survival, mean normalized GDA flow, and histology were compared. RESULTS: 12 swine (mean 57.8 ± 7.6 kgs) were included, six per group. Baseline weight, HR, MAP and GDA flows were not different. Within 5 min following SMA clamping, all 12 animals had an increase in MAP without other intervention from 81.7 to 105.5 mmHg (29.1%, P < 0.01) with a concomitant 74.9% increase in GDA flow as compared to baseline (P < 0.01). Beyond 45 min postclamp, MAP was greater in the MP group as intended, as were GDA flows. Median time to irreversibly ischemic bowel was 31% longer for MAP push animals (CT: 178 versus MP: 233 min, P = 0.006), Hazard Ratio of CT 8.85 (95% CI: 1.86-42.06); 3/6 MP animals versus 0/6 CT animals with bowel survived to predetermined end point. CONCLUSIONS: In this swine model of acute complete proximal SMA occlusion, increasing MAP >90 mmHg with norepinephrine was associated with an increase in macrovascular blood flow through the GDA and bowel survival. Norepinephrine was not associated with worse bowel survival and a MAP push may increase the time window where ischemic bowel can be salvaged.