BACKGROUND

Spontaneous isolated superior mesenteric artery dissection (SISMAD) is a rare vascular condition where the superior mesenteric artery is affected by dissection without involving other arteries. Its incidence is estimated at 0.06% to 0.08% globally. The possible causes include polyarteritis nodosa (PAN), an autoimmune disease affecting medium-sized arteries. SISMAD can manifest with various clinical presentations, from asymptomatic to acute bowel ischemia, warranting consideration when common causes of acute abdomen are ruled out.

This is the case of a 44-year-old female Filipino, hypertensive, who complained of abdominal pain, initially managed as intestinal amoebiasis. Abdominal examination showed a soft, non-tender abdomen with no guarding, making the symptoms disproportionate to physical examination. Due to persistence of symptoms despite a full antibiotic course, further workup was done. Computed tomography (CT) scan of the whole abdomen with contrast revealed an isolated dissection of the proximal superior mesenteric artery (SMA) with thrombosis which was confirmed on CT angiography. The diagnosis of PAN was established based on the correlation of clinical presentation, laboratory findings and imaging results. Conservative management was done and to address the thrombosis, anticoagulation with heparin was initiated. The patient was also given methylprednisolone pulse therapy and cyclophosphamide with good response. Resolution of symptoms noted and she was eventually discharged improved.

SISMAD and PAN are independently rare conditions. This unique case involved both diseases in a 44-year-old Filipino female, and to date, there have been no reported similar cases worldwide. Early diagnosis of the disease requires a high degree of suspicion and pattern recognition. This is crucial for timely treatment and improved prognosis. Furthermore, close surveillance is important to identify potential relapses even after symptom resolution.

Isolated superior mesenteric artery dissection (ISMAD) has attracted more and more clinicians' attention in recent years. Patients onset of ISMAD often present with abdominal pain. The misdiagnosis or miss diagnosis is common because of the non-specific symptoms and signs, which even can endanger lives in serious cases. Imaging classification is of great significance for diagnosis and treatment of ISMAD. The Sakamoto classification and the Yun classification are two classical classified methods. However, with the further study of ISMAD, various new classifications emerge. Conservative treatment was once considered as the preferred. As the rapid development of endovascular therapy and the great progress of new devices, stenting therapy can significantly improve symptoms and achieve satisfactory long-term effects, and be even expected to become the preferred method for clinical therapy of ISMAD. However, the long-term effects of endovascular therapy still need a large number of follow-up data, and complications after stent implantation can't be ignored.
Humans ; Mesenteric Artery, Superior ; Treatment Outcome ; Tomography, X-Ray Computed ; Aortic Dissection/therapy* ; Stents ; Endovascular Procedures ; Retrospective Studies

The superior mesenteric artery (SMA) is one of the visceral branches of the abdominal aorta. It has multiple branches to supply blood and nutrition to the intestinal segment, and these form an anastomosis with each other. SMA injuries are usually classified as major visceral artery injuries, and have an incidence of <1%. The clinical manifestations of patients with SMA injuries include intra-abdominal bleeding and peritoneal irritation. The compromised blood supply can lead to intestinal ischemia and perforation. These injuries are often not diagnosed in time and have significant mortality rates of 25%‍-‍68% due to the lack of specific features (Maithel et al., 2020). Not only that, but patients with less severe trauma or no visible damage on initial examination may still have clinically significant intra-abdominal injuries (Nishijima et al., 2012). Emergency departments often encounter multiple cases that require urgent diagnosis and treatment (Li et al., 2021; Zhang et al., 2021; Zhou et al., 2021), and therefore, it is imperative to diagnose and manage these rare injuries expeditiously.
Humans ; Mesenteric Artery, Superior/surgery* ; Abdominal Injuries/diagnosis* ; Intestines

When abdominal neoplasms originating from the pancreas or nearby organs locally involving the superior mesenteric artery (SMA), complete resection is still the only hope for cure. However, SMA resection and reconstruction is a complex surgical procedure associated with high postoperative morbidity and mortality. Intestinal autotransplantation has recently emerged in clinical practice as a treatment option for selected patients with neoplasms involving the SMA. The original procedure involved en bloc removal of a tumor together with the intestine, ex vivo resection and reconstruction of gastrointestinal tract by an intestinal autograft. To further refine this complex procedure, a modified method was developed in which a segmental bowel autograft is selected and harvested first during the initial stage of the operation, and radical resection of the neoplasm is carried out thereafter. The modification would better protect a healthy bowel autograft from potential damage due to prolonged warm ischemia and allow the subsequent lengthy process of dissection to be performed in an unrushed manner. Furthermore, this alteration would better adhere to the general principles of minimal tumor manipulation during operation and potentially decrease the risks of tumor implantation during in vitro organ perfusion. Although intestinal autotransplantation has expanded eligibility for resection of otherwise unresectable lesions involving the SMA, its operative complexity, high risks, and post-operative complications largely limit its clinical applications.
Humans ; Intestines ; Mesenteric Artery, Superior/surgery* ; Pancreatic Neoplasms ; Transplantation, Autologous

There are still controversies as to the location of ligating the inferior mesenteric artery and the central lymph node dissection during rectal cancer surgery. The reason is that the level of evidence in this area is low. Existing studies are mostly retrospective, analyses or small-sample randomized controlled trials. These results showed no significant differences between high-ligation and low-ligation, in terms of anastomotic leakage and other short-term postoperative complications. Low-ligation seems better for the recovery of postoperative genitourinary function. Due to the low rate of central lymph node metastasis and many other confounding factors that affect the survival rate, it is difficult to conclude the survival benefits of ligation site or central node dissection. It is necessary to carry out some targeted, well-designed, large-scale randomized controlled trials to explain the related issues of inferior mesenteric artery ligation site and extent of central lymphadenectomy.
Humans ; Laparoscopy/methods* ; Ligation/methods* ; Lymph Node Excision/methods* ; Mesenteric Artery, Inferior/surgery* ; Mesentery ; Rectal Neoplasms ; Rectum/surgery* ; Retrospective Studies

Splenic flexure colon cancer occurs at a relatively lower rate than colon cancer of other sites. It is also associated with more advanced disease and higher rate of acute obstruction. The splenic flexure receives blood supply from both superior and inferior mesenteric arteries (SMA and IMA), and therefore has lymphatic drainage to both areas. The blood supply is also highly variable, causing difficulties in determining the main feeding vessels and the main direction of lymph drainage. Few studies with limited cases focused on this specific tumor site with respect to the patterns of lymph node spread, especially the main lymph node status and the value of its dissection. The lack of information limits the development of a consensus on the extent of surgical resection and lymphadenectomy. Adequate mobilization of the colon facilitates a sufficient length of bowel resection and the high ligation of feeding arteries from both SMA and IMA. Further evidence on the chnoice of procedures and the extent of lymph node dissection need multicenter collaboration, with the use of modern techniques, including CT 3D reconstruction of the colon and angiography, as well as intraoperative fluorescent real-time imaging of lymph nodes.
Colon, Transverse/surgery* ; Colonic Neoplasms/surgery* ; Humans ; Laparoscopy ; Lymph Node Excision/methods* ; Lymph Nodes/pathology* ; Mesenteric Artery, Inferior/surgery*

The concept of total mesorectal resection provides a quality control standard that can be followed for radical resection of rectal cancer, but some anatomical problems are still controversial. Compared with traditional open surgery, laparoscopic radical rectal surgery has better surgical vision, better neurological protection, better operating space. However, if the surgeon has insufficient understanding of the anatomy, collateral damage may occur, such as uncontrollable bleeding during the operation, postoperative urination and defecation dysfunction and so on. Based on the interpretation of the researches at home and abroad, combined with the clinical experience, we elucidate some associated issues, including anatomic variation of inferior mesenteric vessels, the controversy of inferior mesenteric artery ligation plane, the controversy of lymph node dissection in No. 253, the anatomical variation of middle rectal artery, and the anatomical controversy of lateral lymph node dissection in rectal cancer, in order to provide better cognitive process for the clinical front-line surgeons.
Humans ; Laparoscopy ; Lymph Node Excision ; Lymph Nodes ; Mesenteric Artery, Inferior ; Rectal Neoplasms/surgery* ; Rectum

Japanese Society for Cancer of the Colon and Rectum (JSCCR) guideline 2019 recommended that lymph node dissection for advanced rectal cancer should include the lymphatic adipose tissue at the root of the inferior mesenteric vessels, but the ligation site of the inferior mesenteric artery (IMA) was not determined, and the NCCN guideline did not indicate clearly whether to retain the left colonic artery (LCA). Controversy over whether to retain LCA is no more than whether it can reduce the incidence of anastomotic complications or postoperative functional damage without affecting the patients' oncological outcome. Focusing on the above problems, this paper reviews the latest research progress. In conclusion, it is believed that the advantages of retaining LCA are supported by most studies, which can improve the blood supply of the proximal anastomosis, and technically can achieve the same range of lymph node dissection as IMA high ligation. However, whether it affects the survival of patients, reduces the incidence of anastomotic leakage, and improves the quality of life of patients, more high-quality evidence-based medical evidence is still needed.
Arteries ; Humans ; Laparoscopy ; Mesenteric Artery, Inferior/surgery* ; Quality of Life ; Rectal Neoplasms/surgery*

The preservation of left colonic artery (LCA) has been accepted by more and more surgeons in the radical resection of rectal cancer, but whether it can reduce anastomotic complications and affect the oncology efficacy remains controversial. This consensus elaborates the significance, anatomical structure, key points of operation techniques, indications and contraindications, and surgical approaches of LCA preservation. Each statement and recommendation was recognized by most experts in the field of colorectal surgery. The purpose of this consensus is to improve the cognitive level of Chinese colorectal surgeons on LCA preservation, so as to standardize the surgical strategies and methods of LCA preservation and furthermore practice, and promote it. The pending issues in this consensus need further high-quality clinical studies.
Anastomotic Leak ; Arteries ; China ; Consensus ; Humans ; Laparoscopy ; Mesenteric Artery, Inferior ; Rectal Neoplasms/surgery*

To access the efficacy of stents for spontaneous isolated dissection of the superior mesenteric artery (SIDSMA). The study is a prospective single-arm study which has been registered on Clinical Trials (NCT03916965). Clinical data and follow-up information of the SIDSMA patients who received stent implantation in the First Affiliated Hospital of Zhejiang University during April 1, 2019 and September 30, 2019 were collected. The patients were recommended to be followed up at 1, 3, 6 and 12 months. A total of 34 patients were enrolled. Their mean age was (54±8) years. Abdominal pain was the most common symptom. Patients received (2.1±0.6) stents on the average. Post-operation hospital stay was (2.7±1.6) days, and the patients were followed up for (2.3±1.9) months (CT angiography) and (5.5±1.7) months (clinical visit/phone call). There was no recurrence of abdominal pain. The CT angiography showed complete remodeling and incomplete remodeling took place in 23 and 9 patients (69.7% and 27.3%), respectively. Two patients (6.1%) had mild in-stent stenosis. No stent rupture or migration was reported. This study demonstrated a satisfactory short-term result of stents implantation for SIDSMA, which indicated the endovascular treatment could be the first-line therapy for SIDSMA.
Aneurysm, Dissecting ; Endovascular Procedures ; Humans ; Mesenteric Artery, Superior ; Middle Aged ; Prospective Studies ; Retrospective Studies ; Stents ; Treatment Outcome