Root Of Superior Mesenteric Artery Research Articles

Feasibility of middle colic artery as a landmark for superior mesenteric artery – first approach in laparoscopic pancreatoduodenectomy: a prospective study

BackgroundSMA-first approach in pancreatoduodenectomy (PD) has been widely applied in open surgery as well as laparoscopy. Finding the superior mesenteric artery (SMA), inferior pancreatoduodenal artery (IPDA), first jejunal artery (J1A) has become a great challenge in laparoscopic PD (LPD). Meanwhile, exposing the midde colic artery (MCA) might be a feasible approach to determine SMA, IPDA, and J1A. Our study aims to find the anatomical correlation between MCA and SMA, IPDA, J1A, especially in SMA-first approach LPD from the left.MethodsUncontrolled clinical trial with 33 patients undergoing LPD had preoperative contrast abdominal CT scan to analyze the anatomical relevance between MCA and SMA, J1A, IPDA. The operation was performed starting with exposing MCA in advance to find SMA, J1A and IPDA. The data was analyzed by SPSS 25.0.Results90.9% of MCA started at 12–3 o’clock from SMA, the mean distance from the SMA root to the MCA and J1A was 56.4 mm and 37.4 mm, respectively. The distance between SMA and J1A was 19 mm. 72.7% J1A started at 9–12 o’clock, 69.7% J1A and IPDA had a common trunk. 78.8% IPDA started at 3–6 o’clock. 100% of the cases had J1A controlled intraoperatively, 81.8% for IPDA when approached from the left, 3% had MCA injury. The mean time to approach from the left was 98 min, median blood loss was 100 ml.ConclusionExposing MCA first helps determine SMA, J1A and IPDA safely, efficiently and faciliates SMA-first approach LPD from the left and complete dissection of the mesopancreas and lymph nodes.

Different hemodynamic factors cause the occurrence of superior mesenteric atherosclerotic stenosis and superior mesenteric artery dissection.

To compare the hemodynamic factors involved in the occurrence of superior mesenteric atherosclerotic stenosis (SMAS) and superior mesenteric artery (SMA) dissection (SMAD). Hospital records were searched to identify consecutive patients who were diagnosed with SMAS or SMAD between January 2015 and December 2021. A computational fluid dynamics (CFD) simulation method was used to assess the hemodynamic factors of the SMA in these patients. Histologic analysis was also performed on SMA specimens obtained from 10 cadavers, and scanning electron microscopy was used to evaluate collagen microstructure. A total of 124 patients with SMAS and 61 patients with SMAD were included. Most SMASs were circumferentially distributed at the SMA root, whereas the origin of most SMADs was located on the anterior wall of the curved segment of the SMA. Vortex, higher turbulent kinetic energy (TKE), and lower wall shear stress (WSS) were observed near plaques; higher TKE and WSS were seen near dissection origins. The intima in the SMA root (388.5 ± 202.3 µm) was thicker than in the curved (243.8 ± 100.5 µm; p = .007) and distal (183.7 ± 88.0 µm; p < .001) segments. The media in the anterior wall (353.1 ± 37.6 µm) was thinner than that in the posterior wall (473.7 ± 142.8 µm; p = .02) in the curved segment of the SMA. The gaps in the lamellar structure in the SMA root were larger than in the curved and distal segments. The collagen microstructure was more substantially disturbed in the anterior wall than in the posterior wall in the curved segment of the SMA. Different hemodynamic factors in different portions of the SMA are related to local pathological changes in the SMA wall and may lead to the occurrence of SMAS or SMAD.

Preoperative Simulation of Ileal Pouch-Anal Anastomosis in Patients With Ulcerative Colitis Using a 3-Dimensional Printed Model.

During restorative proctocolectomy with ileal pouch-anal anastomosis for ulcerative colitis-associated colorectal cancer or dysplasia, ileal pouch-anal handsewn anastomosis (IAA) is preferred to avoid the risk of cancer development in the remaining rectal mucosa. However, there is a risk of the ileal pouch not reaching the anus with this procedure. Here, we created deformable 3-dimensional (3D) models for simulation. Six patients who underwent IAA without vessel ligation and 5 patients who underwent ileal pouch-anal canal double-stapled anastomosis (IACA) because the ileal pouch did not reach the anus were studied. A 3D printer was used to create deformable 3D models from the data obtained from computed tomography scans. The positional relationship among the mesenteric arteries, pubis, and coccyx were evaluated. The distance between the superior mesenteric artery root and the tip of the ileal artery was longer in the IAA group than that in the IACA group (IAA vs IACA: 26.2 ± 2.1 cm vs 20.9 ± 1.6cm). The distance from the tip of the ileal artery to the coccyx (IAA vs IACA: 6.7 ± 1.7 cm vs 12.1 ± 2.1 cm) and the distance from the tip of the ileal artery to the lower edge of the pubis (IAA vs IACA; 8.1 ± 1.3 cm vs 12.7 ± 2.4 cm) were longer in the IACA group than those in the IAA group. We established a method for creating 3D deformable models of patients with ileal pouch-anal anastomosis. These 3D models may be useful for preoperative simulation.

Da Vinci robotic assisted pancreaticoduodenectomy with superior mesenteric vein resection and reconstruction

This study demonstrated Da Vinci robot assisted pancreaticoduodenectomy with superior mesenteric vein (SMV) resection and reconstruction. The patient was diagnosed with pancreatic head cancer preoperatively. After anesthesia, trocars were placed by “six-hole method”, and then constant pressure pneumoperitoneum was established. The first step was to remove the gallbladder, open the gastrocolonic ligament, and expose the pancreas and surrounding tissues. After making a Kocher incision, we dissected duodenum, inferior vena cava and uncinate process of pancreas, and then cleaned lymph nodes in groups 13 and 16A. After the stomach was severed using linear stapler, the right gastric artery was dissected and ligated. In this case, the adhesion around the pancreas and common hepatic artery was serious, so the pancreas was transected firstly. The gastroduodenal artery was dissected from the upper edge of the pancreas, and the lymph nodes in groups 7, 8, 9 and 12 were cleaned to expose the common bile duct and portal vein. The common bile duct was transected above the confluence plane of the cystic duct. After opening the colonic mesentery on the left side of the superior mesenteric artery (SMA), the jejunum was severed with a linear cutting obturator. The uncinate process was treated through the middle artery approach; the inferior pancreaticoduodenal artery was severed and lymph nodes were cleaned to the root of SMA and celiac trunk. The tumor and part of the invaded SMV were removed and end-to-end SMV anastomosis was performed. The proper hepatic artery was wrapped with the round hepatic ligament. To protect the stump of gastroduodenal artery, we padded the round hepatic ligament below the pancreaticoduodenal anastomosis. The modified Blumgart method was used for pancreaticointestinal duct to mucosal anastomosis. 4-0 ​V-Lock suture was used for continuous suture of posterior wall and anterior wall respectively, and finally gastrointestinal side-to-side anastomosis was performed. The operation time was 360 ​min and the intraoperative bleeding was 200 ​mL. The patient was discharged 7 days after operation.

Into the future: a pilot study combining imaging with molecular profiling for preoperative prediction of resectability in ovarian cancer (068)

Objectives: We sought to determine the joint predictive value of tumor molecular subtype and CT imaging data in predicting surgical outcomes prior to primary debulking surgery (PDS) in Stage IIIC/IV high-grade serous ovarian cancer patients. Methods: Patients undergoing PDS for Stage IIIC/IV were included. Based on CT imaging, a continuous CT-score indicative of overall disease burden was defined based on six CT measurements of anatomic involvement: (1) diaphragm disease; (2) gastrohepatic/porta hepatis; (3) root of superior mesenteric artery; (4) presence of moderate to severe ascites; (5) intrahepatic lesion, and (6) diffuse peritoneal thickening > 4mm. Patients were then classified as CT-low or CT-high if their score was ≤2 or ≥3, respectively. Molecular subtypes were derived from mRNA profiling of chemo-naïve tumors; women were classified as having mesenchymal (MES) subtype or non-MES subtype tumors. Patients were classified as having no gross residual disease (RD0) or any gross residual disease less than 1 cm (RD1), or gross residual disease greater than 1 cm (RD2). Multivariate regression models were fit to predict RD. The four cohorts, (i) non-MES & CT-low, (ii) non-MES & CT-high, (iii) MES & CT-low, and (iv) MES & CT-high, were compared with Fisher’s exact tests to examine the association with RD and surgical complexity. Graphical Abstract View Large Image Figure Viewer Download Hi-res image Conclusions: Preoperative CT imaging combined with tumor molecular subtyping can identify a subset of women for whom successful primary surgery is unlikely. Preoperative tumor sampling may be useful in advanced OC to better triage these cases to alternative approaches. Objectives: We sought to determine the joint predictive value of tumor molecular subtype and CT imaging data in predicting surgical outcomes prior to primary debulking surgery (PDS) in Stage IIIC/IV high-grade serous ovarian cancer patients. Methods: Patients undergoing PDS for Stage IIIC/IV were included. Based on CT imaging, a continuous CT-score indicative of overall disease burden was defined based on six CT measurements of anatomic involvement: (1) diaphragm disease; (2) gastrohepatic/porta hepatis; (3) root of superior mesenteric artery; (4) presence of moderate to severe ascites; (5) intrahepatic lesion, and (6) diffuse peritoneal thickening > 4mm. Patients were then classified as CT-low or CT-high if their score was ≤2 or ≥3, respectively. Molecular subtypes were derived from mRNA profiling of chemo-naïve tumors; women were classified as having mesenchymal (MES) subtype or non-MES subtype tumors. Patients were classified as having no gross residual disease (RD0) or any gross residual disease less than 1 cm (RD1), or gross residual disease greater than 1 cm (RD2). Multivariate regression models were fit to predict RD. The four cohorts, (i) non-MES & CT-low, (ii) non-MES & CT-high, (iii) MES & CT-low, and (iv) MES & CT-high, were compared with Fisher’s exact tests to examine the association with RD and surgical complexity. Conclusions: Preoperative CT imaging combined with tumor molecular subtyping can identify a subset of women for whom successful primary surgery is unlikely. Preoperative tumor sampling may be useful in advanced OC to better triage these cases to alternative approaches.

Long Distance Between the Superior Mesenteric Artery Root and Bottom of the External Anal Sphincter Is a Risk Factor for Stoma Outlet Obstruction After Total Proctocolectomy and Ileal‐Pouch Anal Anastomosis for Ulcerative Colitis

BackgroundStoma outlet obstruction (SOO) is much more common after total proctocolectomy (TPC) and ileal‐pouch anal anastomosis (IPAA) for ulcerative colitis (UC) compared to after rectal surgery for cancer. Few prior reports have evaluated anatomical risk factors for SOO. In this study we aimed to clarify the risk factors for SOO after IPAA, focusing on the anatomical perspective.MethodsThis study included 68 UC patients who underwent IPAA with diverting ileostomy. These cases were analyzed based on clinicopathological factors and computed tomography (CT)‐based anatomical factors.ResultsSOO was identified in 18 patients (26.5%). We compared this SOO group with the non‐SOO group. The two groups significantly differed in sex distribution, and patients in the SOO group tended to have a longer postoperative hospital stay. Regarding surgery‐related factors, patients who underwent two‐stage surgery and experienced high‐output syndrome tended to develop SOO. Analysis of anatomical risk factors revealed that SOO was more common in patients with a longer distance between the root of their superior mesenteric artery and the bottom of the external anal sphincter (rSMA‐bEAS). This tendency remained significant even with adjustment for patient height. In multivariate analyses, adjusted rSMA‐bEAS (>191.0 mm/m) and male sex were independent risk factors associated with SOO.ConclusionA long rSMA‐bEAS distance suggests that the mesentery is likely to be under tension. In such cases, surgeons should endeavor to avoid tension in the mesentery as much as possible.

Isolated superior mesenteric artery dissection: CTA features and clinical relevance.

To determine the detailed computed tomography angiography (CTA) features of isolated superior mesenteric artery dissection (ISMAD), aiming to improve the current understanding of ISMAD. We retrospectively analyzed 57 patients with confirmed diagnoses of ISMAD with CTA from June 2011 to June 2018 in our hospital. The superior mesenteric artery (SMA) angle, entry site of dissection, and features of both false and true lumen were analyzed individually. In general, middle-aged men with atherosclerosis (42.1%), hypertension (35.3%), or long-term smoking (33.3%) were the main populations. 80.7% of patients can be discharged successfully after conservative treatment. 87% of patients had a right (or almost right) SMA angle, and the entry site of dissection in 90% of patients occurred in the curved segment of the SMA. As a polymorphic disease, we can use the coded CTA features to delineate individual cases, including cases beyond the presenting classification systems. The diameter of the true lumen is the only different CTA feature between the conservative treatment group and the interventional treatment group (p = 0.000). The re-entry site (p = 0.501), thrombosis in the false lumen (p = 0.135), the distance between the entry site of dissection and SMA root (p = 0.133), and SMA branch involvement (p = 0.322) had no difference between the 2 groups. Based on CTA analysis, the bending area, especially in the SMA with right or nearly right SMA angle, is the most vulnerable anatomical region for the occurrence of ISMAD. The diameter of true lumen is the determined CTA feature for the decision of treatment. CTA should be recommended as a standardized diagnostic and classification tool for ISMAD.

Isolated Superior Mesenteric Artery Dissection Following Liver Transplant: Report of 3 Cases

BackgroundIsolated superior mesenteric artery (SMA) dissection (SMAD) is considered a relatively rare disease. Especially, isolated SMAD following liver transplant has been rarely reported. Report of CasesAmong 96 consecutive adult recipients who underwent liver transplant at our institution, 3 recipients (3.1%) demonstrated isolated noncommunicating SMAD, type IV according to Sakamoto's classification. Patient characteristics are the following: mean age, 53 years (range, 49–60 years); male to female ratio, 2:1, right lobe graft to left lobe graft ratio, 2:1; operating time, 760 minutes (range, 614–880 minutes); and blood loss, 6570 mL (range, 2435–13,329 mL). New onset of abdominal pain was noted in 33.3% (1/3). The diagnosis was made by the first follow-up computed tomography scan after liver transplant. The mean distance between the proximal end of SMAD and the root of SMA was 21.3 mm (range, 9–40 mm). There were no signs of ischemic changes in the small intestine in any of the 3 patients. Thus, conservative managements such as anticoagulation therapy were performed without other aggressive interventions. One patient died because of subarachnoid hemorrhage. In the other 2 patients, SMAD disappeared at 6 months following the diagnosis. DiscussionThe morbidity of isolated SMAD is around less than 0.1% at the autopsy. Compared with this result, we found significantly higher morbidity rate in liver transplant recipients. It is true that mechanical stress from retraction of the stomach to the caudal end including the root of SMA may play an important role in the onset of SMA dissection. ConclusionIsolated SMA dissection following living donor liver transplant is a rare but potentially life-threatening condition. It is required to ascertain whether emergency revascularization should be considered.

Role of Anatomical Landmarks in Identifying Normal and Transitional Vertebra in Lumbar Spine Magnetic Resonance Imaging.

Study DesignRetrospective study.PurposeIdentification of transitional vertebra is important in spine imaging, especially in presurgical planning. Pasted images of the whole spine obtained using high-field magnetic resonance imaging (MRI) are helpful in counting vertebrae and identifying transitional vertebrae. Counting vertebrae and identifying transitional vertebrae is challenging in isolated studies of lumbar spine and in studies conducted in low-field MRI. An incorrect evaluation may lead to wrong-level treatment. Here, we identify the location of different anatomical structures that can help in counting and identifying vertebrae.Overview of LiteratureMany studies have assessed the vertebral segments using various anatomical structures such as costal facets (CF), aortic bifurcation (AB), inferior vena cava confluence (IC), right renal artery (RRA), celiac trunk (CT), superior mesenteric artery root (SR), iliolumbar ligament (ILL) psoas muscle (PM) origin, and conus medullaris. However, none have yielded any consistent results.MethodsWe studied the locations of the anatomical structures CF, AB, IC, RRA, CT, SR, ILL, and PM in patients who underwent whole spine MRI at our department.ResultsIn our study, 81.4% patients had normal spinal segmentation, 14.7% had sacralization, and 3.8% had lumbarization. Vascular landmarks had variable origin. There were caudal and cranial shifts with respect to lumbarization and sacralization. In 93.8% of cases in the normal group, ILL emerged from either L5 alone or the adjacent disc. In the sacralization group, ILL was commonly seen in L5. In the lumbarization group, ILL emerged from L5 and the adjacent disc (66.6%). CFs were identified at D12 in 96.9% and 91.7% of patients in the normal and lumbarization groups, respectively. The PM origin was observed from D12 or D12–L1 in most patients in the normal and sacralization groups.ConclusionsCF, PM, and ILL were good identification markers for D12 and L5, but none were 100% accurate.

Laparoscopic pancreaticoduodenectomy: right-inferior-posterior "artery first" approach

To discuss the application of right-inferior-posterior "artery first" approach in laparoscopic pancreaticoduodenectomy. Clinical data of 17 patients who underwent laparoscopic pancreaticoduodenectomy through right-inferior-posterior "artery first" approach in our department from February 2014 to April 2015 were retrospectively analyzed. The operation began at the inferior flexure of duodenum. After entering the Toldt's space, the left renal vein (LRV) was revealed and the root of superior mesenteric artery (SMA) was exposed just above the LRV. SMA was dissected along its trunk till the horizontal part of duodenum. Of these 17 cases, adenocarcinoma of pancreatic head was observed in 5 cases, adenosquamous carcinoma in 2 cases, mucinous cycstic neoplasm in 1 case, adenocarcinoma of lower common bile duct in 4 cases, and duodenal papilla cancer in 5 cases. Fifteen cases were accomplished successfully with laparoscopy and 2 cases were converted to open approach. The average operating time was (320 ± 85) min and mean intraoperative blood loss was (305 ± 175) ml. The cutting margins were tumor negative in all the patients. The average number of harvested lymph node was 15.4 ± 6.5. Postoperative complication occurred in 5 cases. Two cases of bile leakage and 2 cases of pancreatic fistula were cured with conservative treatment. One case of delayed abdominal hemorrhage was resolved with reoperation. Right-inferior-posterior "artery first" approach is safe and feasible in laparoscopic pancreaticoduodenectomy.

Postprandial abdominal pain owing to isolated enteric duplication cyst in the superior mesenteric artery root: sonographic and magnetic resonance imaging features

A 7-year-old girl presented to the emergency department with postprandial abdominal pain. An abdominal sonogram revealed a retroperitoneal septated cystic lesion. Magnetic resonance imaging showed a septated cystic lesion in the superior mesenteric artery (SMA) root with a vessel originating from the proximal SMA supplying the cyst wall and a deformed adjacent aortic contour. A laparotomy was performed and confirmed the presence of an isolated enteric duplication cyst with its own blood supply from the SMA and marked perilesional adhesions to the duodenal loop and aorta. Histopathologic study was consistent with a duplication. To our knowledge, this is the first report of isolated enteric duplication cyst in the superior mesenteric root with perilesional adhesion leading to postprandial abdominal pain, which was successfully relieved after surgery.

Noradrenalin-Secreting Retroperitoneal Schwannoma Resected by Hand-Assisted Laparoscopic Surgery: Report of a Case

A 66-year-old woman was admitted to our hospital for investigation of a retroperitoneal mass. She was asymptomatic but her serum noradrenalin and vanillylmandellic acid levels were increased remarkably. Computed tomographic angiography showed a mass in the left side of the superior mesenteric artery (SMA) divergence, 6 x 4 cm in size, supplied mainly by the left adrenal artery. We performed hand-assisted laparoscopic surgery (HALS) using a Cavitron ultrasonic surgical aspirator. Abdominal exploration revealed that the tumor was located in the left side of the SMA root, but was not adhered to the adjacent organs. Her vital signs remained stable during the operation. Microscopic examination revealed a palisade formation, confirming a histopathological diagnosis of degenerated schwannoma (Antoni type B). Immunohistologically, the tumor cells were stained with S-100 protein and neuron-specific enolase. Her noradrenalin level normalized immediately after the operation and she remains in good health 3 years 2 months later.

A CASE OF HETEROCHRONOUS DOUBLE CANCER OF THE RECTUM AND STOMACH ASSOCIATED WITH SUPERIOR MESENTERIC ARTERIAL EMBOLISM

Recent experience with heterochronous double cancer of the rectum and stomach in a 67-year-old man, associating with superior mesenteric arterial embolism in the course of observation which could be successfully managed by extensive excision of the intestine, is described. the patient was admitted to the hospital because of severe abdominal pain. There were previous histories of having a rectal cancer which was treated by low anterior excision 5 years before and an early gastric cancer 3 years before, for which the patient denied to be treated. Laparotomy was carried out within 5 hours after the onset of the pain. During surgery, necrotizing lesions extending from the duodenal horizontal portion to entire the small intestine, and from the ileocecal region to remnant sigmoid colon were found. Partial excision of the duodenum, total excision of the small intestine, and extended excision of the colon were performed. Reconstruction was impossible and gastrostomy was made. Resected specimen showed a thrombolic embolism caused by a thrombus at the root of superior mesenteric artery. After surgery the patient was able to take fluids in the combinative use of IVH, but the impaired hepatic function and jaundice were aggravated. He died of MOF on the 42nd postoperative day. It is indicated that, if laparotomy can be performed in an early period after the onset of the disease, and if every effort is made to prevent shock and MOF after surgery, we can expect a long survival in these patients even though extended excision of the intestine can not be avoided.

Effects of anti-shock agents on the re-opened superior mesenteric artery flow

We investigated intestinal blood circulation after re-opening of a fixed-time occlusion of the superior mesenteric artery (SMA) in rabbits. The SMA root was occluded for 60 minutes, after which blood pressure and SMA flow were monitored for one hundred minutes under the administration with fluid infusion of three anti-shock agents; dopamine, phenoxybenzamine and dexamethasone. The intestinal wall tissue circulation in parallel with SMA flow was also studied. Blood pressure and SMA flow decreased after release of the SMA occlusion (SMAO), as compared those during pre-occlusive time in the control group. Fluid infusion alone did not improve blood pressure and SMA flow. Pre-administration of dexamethasone with fluid infusion improved blood pressure, SMA flow and the survival rate. Phenoxybenzamine with fluid infusion improved SMA flow, despite the low blood pressure. Circulatory damage to the intestinal wall was more extensive than that to SMA flow. These findings suggest that the severity and mortality of SMAO shock was not caused by plasma loss but rather by toxic metabolites and endotoxin from the ischemic intestine.