Significance of pathological positive superior mesenteric/portal venous invasion in pancreatic cancer

BACKGROUND： Pancreaticoduodenectomy with superior mesenteric/portal venous resection for pancreatic ductal ad- enocarcinoma （PDAC） is frequently performed with no added morbidity or mortality in case of tumor abutment to the superior mesenteric or portal vein so as to obtain a margin negative resection. True histopathological portal vein invasion is found only in a small subset of such patients. The aim of this review aimed to discuss the significance of histopathological venous invasion in PDAC.DATA SOURCES： For this review available data was searched from PubMed and analyzed. No randomized trials have been published on this topic. RESULTS： Existing data on prognostic factors in histopathological venous invasion by PDAC are limited and recent studies indicate worse survival in this subgroup of patients. In addition, venous invasion in PDAC has been associated with large tumors, involved lymph nodes, perineural invasion and R1 resection. The survival of patients with portal venous re- section but without histologic venous invasion is reportedly better than those with histopathological venous invasion; though conflicting studies do exist on the subject. Some studies also relate the depth of venous invasion to prognosis after surgical resection of PDAC. CONCLUSIONS： Frank/＇histopathological＇ invasion of superior mesenteric/portal venous and R1 resection indicate a very poor survival. Such patients may be given the opportunity of benefit of neoadjuvant treatment.

Percutaneous transhepatic stenting for acute superior mesenteric vein stenosis after pancreaticoduodenectomy with portal vein reconstruction:A case report

BACKGROUND Percutaneous transhepatic stent placement has become a common strategy for the postoperative treatment of portal vein(PV)/superior mesenteric veins(SMV)stenosis/occlusion.It has been widely used after liver transplantation surgery;however,reports on stent placement for acute PV/SMV stenosis after pancreatic surgery within postoperative 3 d are rare.CASE SUMMARY Herein,we reported a case of intestinal edema and SMV stenosis 2 d after pancreatic surgery.The patient was successfully treated using stent grafts.Although the stenosis resolved after stent placement,complications,including bleeding,pancreatic fistula,bile leakage,and infection,made the treatment highly challenging.The use of anticoagulants was adjusted multiple times to prevent venous thromboembolism and the risk of bleeding.After careful treatment,the patient stabilized,and stent placement effectively managed postoperative PV/SMV stenosis.CONCLUSION Stent placement is effective and feasible for treating acute PV/SMV stenosis after pancreatic surgery even within postoperative 3 d.

Laparoscopic pancreaticoduodenectomy with portal or superior mesenteric vein resection and reconstruction for pancreatic cancer:A single-center experience

Background: Open pancreaticoduodenectomy(OPD) with portal or superior mesenteric vein resection and reconstruction has been applied in pancreatic cancer patients with tumor infiltration or adherence. However, it is controversial whether laparoscopic pancreaticoduodenectomy(LPD) with major vascular resection and reconstruction is feasible. This study aimed to evaluate the safety and feasibility of LPD with major vascular resection compared with OPD with major vascular resection. Methods: We reviewed data for all pancreatic cancer patients undergoing LPD or OPD with vascular resection at Department of Pancreatic Surgery, Fudan University Shanghai Cancer Center, between February 2018 and May 2022. We compared the preoperative, intraoperative, and postoperative clinicopathological data of the two groups to conduct a comprehensive evaluation of LPD with major vascular resection. Results: A total of 63 patients underwent pancreaticoduodenectomy(PD) with portal or superior mesenteric vein resection and reconstruction, including 25 LPDs and 38 OPDs. The LPD group had less intraoperative blood loss(200 vs. 400 m L, P < 0.001), lower proportion of intraoperative blood transfusion(16.0% vs. 39.5%, P = 0.047), longer operation time(390 vs. 334 min, P = 0.004) and shorter postoperative hospital stay(11 vs. 14 days, P = 0.005). There was no perioperative death in all patients. There was no significant difference in the incidence of total postoperative complications, grade B/C postoperative pancreatic fistula, delayed gastric emptying and abdominal infection between the two groups. No postpancreatectomy hemorrhage nor bile leakage occurred during perioperative period. There was no significant difference in R0 resection rate and number of lymph nodes harvested between the two groups. Patency of reconstructed vessels in the two groups were 96.0% and 92.1%, respectively( P = 0.927). Conclusions: LPD with portal or superior mesenteric vein resection and reconstruction was safe, feasible and oncologically acceptable for selected patients with pancreatic cancer, and it can achieve similar or even better perioperative results compared to open approach.

Mesenteric venous thrombosis in a young adult:A case report and review of the literature

BACKGROUND Acute mesenteric vein thrombosis(MVT)accounts for only 2%–10%of all cases of acute mesenteric ischaemia,with an incidence rate of~0.1%in Europe and the United States.It represents<10%of mesenteric infarction cases and is seen predominantly in older adults.In younger individuals,MVT is uncommon,with 36%of cases having unidentified mechanisms and causes.CASE SUMMARY A 27-year-old man presented to the emergency department on February 29,2024,with a chief complaint of intermittent abdominal pain for 3 day.He was previously in good health.As the abdominal pain was not alleviated by conventional treatment,an abdominal computed tomography(CT)scan was performed,which showed increased density in the portal and mesenteric veins.Further imaging,including portal vein ultrasound,mesenteric CT angiography,and enhanced abdominal CT,revealed widespread thrombosis of the portal vein system(including the main portal vein,left and right branches,proximal mesenteric vein,and splenic vein).After 10 day of thrombectomy and anticoagulation therapy,the patient’s abdominal pain had improved significantly.Follow-up assessments indicated that portal venous blood flow had largely returned to normal.He was discharged on March 9,2024.During a follow-up exam 2 months later,repeat abdominal enhanced CT showed that the previously detected thrombi were no longer visible.CONCLUSION Clinicians should remain vigilant for acute MVT in young patients presenting with abdominal pain,to prevent misdiagnosis of this fatal condition.

Ligamentum teres hepatis as a graft for portal and/or superior mesenteric vein reconstruction:From bench to bedside

BACKGROUND Pancreaticoduodenectomy combined with portal vein(PV)and/or superior mesenteric vein(SMV)resection in patients with pancreaticobiliary malignancy has become a common surgical procedure.There are various grafts currently used for PV and/or SMV reconstruction,but each of these grafts have certain limitations.Therefore,it is necessary to explore novel grafts that have an extensive resource pool,are low cost with good clinical application,and are without immune response rejection or additional damage to patients.AIM To observe the anatomical and histological characteristics of the ligamentum teres hepatis(LTH)and evaluate PV/SMV reconstruction using an autologous LTH graft in pancreaticobiliary malignancy patients.METHODS In 107 patients,the post-dilated length and diameter in resected LTH specimens were measured.The general structure of the LTH specimens was observed by hematoxylin and eosin(HE)staining.Collagen fibers(CFs),elastic fibers(EFs),and smooth muscle(SM)were visualized by Verhoeff-Van Gieson staining,and the expression of CD34,factor VIII-related antigen(FVIIIAg),endothelial nitric oxide synthase(eNOS),and tissue type plasminogen activator(t-PA)were detected using immunohistochemistry in LTH and PV(control)endothelial cells.PV and/or SMV reconstruction using the autologous LTH was conducted in 26 patients with pancreaticobiliary malignancies,and the outcomes were retrospectively analyzed.RESULTS The post-dilated length of LTH was 9.67±1.43 cm,and the diameter at a pressure of 30 cm H2O was 12.82±1.32 mm at the cranial end and 7.06±1.88 mm at the caudal end.Residual cavities with smooth tunica intima covered by endothelial cells were found in HE-stained LTH specimens.The relative amounts of EFs,CFs and SM in the LTH were similar to those in the PV[EF(%):11.23±3.40 vs 11.57±2.80,P=0.62;CF(%):33.51±7.71 vs 32.11±4.82,P=0.33;SM(%):15.61±5.26 vs 16.74±4.83,P=0.32].CD34,FVIIIAg,eNOS,and t-PA were expressed in both LTH and PV endothelial cells.The PV and/or SMV reconstructions were successfully completed in all patients.The overall morbidity and mortality rates were 38.46%and 7.69%,respectively.There were no graft-related complications.The postoperative vein stenosis rates at 2 wk,1 mo,3 mo and 1 year were 7.69%,11.54%,15.38%and 19.23%,respectively.In all 5 patients affected,the degree of vascular stenosis was less than half of the reconstructed vein lumen diameter(mild stenosis),and the vessels remained patent.CONCLUSION The anatomical and histological characteristics of LTH were similar to the PV and SMV.As such,the LTH can be used as an autologous graft for PV and/or SMV reconstruction in pancreaticobiliary malignancy patients who require PV and/or SMV resection.

Mesenteric adipose tissue B lymphocytes promote intestinal injury in severe acute pancreatitis by mediating enteric pyroptosis

Background:Visceral adipose tissue(VAT)has been linked to the severe acute pancreatitis(SAP)prognosis,although the underlying mechanism remains unclear.It has been reported that pyroptosis worsens SAP.The present study aimed to verify whether mesenteric adipose tissue(MAT,a component of VAT)can cause secondary intestinal injury through the pyroptotic pathway.Methods:Thirty-six male Sprague Dawley(SD)rats were divided into six different groups.Twelve rats were randomly divided into the SAP and control groups.We monitored the changes of MAT and B lymphocytes infiltration in MAT of SAP rats.Twelve SAP rats were injected with MAT B lymphocytes or phosphate buffer solution(PBS).The remaining twelve SAP rats were first injected with MAT B lymphocytes,and then with MCC950(NLRP3 inhibitor)or PBS.We collected blood and tissue samples from pancreas,gut and MAT for analysis.Results:Compared to the control rats,the SAP group showed inflammation in MAT,including higher expression of tumor necrosis factor(TNF-α)and interleukin-6(IL-6),lower expression of IL-10,and histological changes.Flow cytometry analysis revealed B lymphocytes infiltration in MAT but not T lymphocytes and macrophages.The SAP rats also exhibited intestinal injury,characterized by lower expression of zonula occludens-1(ZO-1)and occludin,higher levels of lipopolysaccharide and diamine oxidase,and pathological changes.The expression of NLRP3 and n-GSDMD,which are responsible for pyroptosis,was increased in the intestine of SAP rats.The injection of MAT B lymphocytes into SAP rats exacerbated the inflammation in MAT.The upregulation of pyroptosis reduced tight junction in the intestine,which contributed to the SAP progression,including higher inflammatory indicators and worse histological changes.The administration of MCC950 to SAP+MAT B rats downregulated pyroptosis,which subsequently improved the intestinal barrier and ameliorated inflammatory response of SAP.Conclusions:In SAP,MAT B lymphocytes aggravated local inflammation,and promoted the injury to the intestine through the enteric pyroptotic pathway.

Superior Mesenteric Artery Syndrome, a Rare Complication of Severe Malnutrition: Two Cases from a Subsaharian Endocrinology Department

Introduction: Superior mesenteric artery syndrome (SMAS), a rare diagnosis due to compression of the third duodenum between the superior mesenteric artery (SMA) and the aorta resulting in bowel obstruction, may lead to severe malnutrition. We report two cases of patients hospitalised in the Internal Medicine, Endocrinology, Diabetology, and Nutrition Department of the National Hospital Center (NHC) of Pikine. Observations: Patient 1: A 35-year-old female was referred for an aetiological diagnosis due to a rapid weight loss of 15 kilograms in one month, accompanied by persistent vomiting, following an appendectomy performed a month before admission. Upon clinical examination, she presented severe malnutrition (Buzby index of 76%), early post-prandial chronic vomiting, and a poor general condition. An abdominal CT scan revealed aortomesenteric clamp syndrome (AMCS) with an angulation between the aorta and the SMA of 13˚. The underlying cause in this patient was severe malnutrition. Fortunately, her condition improved with medical treatment. Patient 2: We report the case of a 30-year-old female hospitalized due to unusual weight-bearing post-prandial epigastric pain and intermittent vomiting over the past six months. Upon physical examination at admission, she exhibited severe malnutrition with a body mass index (BMI) of 14 kg/m2, a Buzby index of 71%, trophic disorders, and a stage IV general condition assessment according to the World Health Organization (WHO). An abdominal CT scan revealed AMCS with an angle between the aorta and the SMA of 22˚ and an aortomesenteric space of 4 mm. The outcome was poor with medical treatment failure and, unfortunately, the patient died before surgery. Conclusion: SMAS is rarely evoked in clinical practice despite the presence of contributing factors and suggestive clinical signs. The prognosis depends on management time.

Application of transmesenteric vein extrahepatic portosystemic shunt in treatment of symptomatic portal hypertension with cavernous transformation of portal vein

Purpose:To evaluate the feasibility and efficacy of a transmesenteric vein extrahepatic portosystemic shunt(TmEPS)for the treatment of cavernous transformation of the portal vein(CTPV).Materials and methods:The clinical data of 20 patients with CTPV who underwent TmEPS between December 2020and January 2022 at Henan Provincial People’s Hospital were retrospectively collected.The superior mesenteric vein(SMV)trunk was patent or partially occluded in these patients.An extrahepatic portosystemic shunt between the inferior vena cava and the SMV was established using a stent graft through an infraumbilical median longitudinal mini-laparotomy.The technical success,efficacy,and complication rates were evaluated,and the preand postoperative SMV pressures were compared.Patients’clinical outcomes and shunt patency were assessed.Results:TmEPS was successfully performed in 20 patients.The initial puncture success rate of the balloon-assisted puncture technique is 95%.The mean SMV pressure decreased from 29.1±2.9 mmHg to 15.6±3.3 mmHg(p<0.001).All symptoms of portal hypertension resolved.No fatal procedural complications occurred.During the follow-up period,hepatic encephalopathy occurred in two patients.The remaining patients remained asymptomatic.All shunts were patent.Conclusions:TmEPS is a feasible,safe,and effective treatment option for patients with CTPV.

Rupture of a giant jejunal mesenteric cystic lymphangioma misdiagnosed as ovarian torsion: A case report

BACKGROUND Cystic lymphangioma is a rare benign tumor that affects the lymphatic system.Mesenteric lymphangiomas in the small bowel are extremely uncommon.CASE SUMMARY We present a 21-year-old female patient who complained of abdominal pain.The diagnosis of ovarian torsion was suspected after abdominopelvic unenhanced computed tomography and ultrasound revealed a large cyst in contact with the bladder,ovary,and uterus.The patient underwent emergency laparotomy per-formed by gynecologists,but it was discovered that the cystic tumor originated from the jejunum.Gastrointestinal surgeons were then called in to perform a cystectomy.Pathological examination confirmed the diagnosis of cystic lymphangioma of the mesentery.The patient had an uneventful postoperative recovery.CONCLUSION Mesenteric lymphangiomas can cause abdominal pain,and imaging techniques can help determine their characteristics,location,and size.Complete surgical excision and pathological examination are considered the standard treatment and diagnostic method.

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.

Emergency rescue of a patient with hemorrhagic shock caused by superior mesenteric artery rupture:A case report

BACKGROUND Superior mesenteric artery(SMA)injuries rarely occur during blunt abdominal injuries,with an incidence of<1%.The clinical manifestations mainly include abdominal hemorrhage and peritoneal irritation,which progress rapidly and are easily misdiagnosed.Quick and accurate diagnosis and timely effective treatment are greatly significant in managing emergent cases.This report describes emergency rescue by a multidisciplinary team of a patient with hemorrhagic shock caused by SMA rupture.CASE SUMMARY A 55-year-old man with hemorrhagic shock presented with SMA rupture.On admission,he showed extremely unstable vital signs and was unconscious with a laceration on his head,heart rate of 143 beats/min,shallow and fast breathing(frequency>35 beats/min),and blood pressure as low as 20/10 mmHg(1 mmHg=0.133 kPa).Computed tomography revealed abdominal and pelvic hematocele effusion,suggesting active bleeding.The patient was suspected of partial rupture of the distal SMA branch.The patient underwent emergency mesenteric artery ligation,scalp suture,and liver laceration closure.In view of conditions with acute onset,rapid progression,and high bleeding volume,key points of nursing were conducted,including activating emergency protocol,opening of the green channel,and arranging relevant examinations with various medical staff for quick diagnosis.The seamless collaboration of the multidisciplinary team helped shorten the preoperative preparation time.Emergency laparotomy exploration and mesenteric artery ligation were performed to mitigate hemorrhagic shock while establishing efficient venous accesses and closely monitoring the patient’s condition to ensure hemodynamic stability.Strict measures were taken to avoid intraoperative hypothermia and infection.CONCLUSION After 3.5 h of emergency rescue and medical care,bleeding was successfully controlled,and the patient’s condition was stabilized.Subsequently,the patient was transferred to the intensive care unit for continuous monitoring and treatment.On the sixth day,the patient was weaned off the ventilator,extubated,and relocated to a specialized ward.Through diligent medical intervention and attentive nursing,the patient made a full recovery and was discharged on day 22.The follow-up visit confirmed the patient’s successful recovery.

Idiopathic mesenteric phlebosclerosis missed by a radiologist at initial diagnosis: A case report

BACKGROUND Idiopathic mesenteric phlebosclerosis(IMP)is a rare type of ischemic colitis characterized by thickening of the wall of the right hemicolon and calcification,sclerosis,and fibrosis of mesenteric veins.The diagnosis of IMP is based on typical clinical features and imaging findings.We report a case of IMP that was initially missed by the radiologist.CASE SUMMARY A 77-year-old woman was admitted to the hospital due to chronic diarrhea for over 2 months.She had been consuming Chinese patent medicines(CPM)containing fructus gardeniae for more than 15 years.Colonoscopy revealed an edematous mucosa,bluish-purple discoloration,erosions,and ulcerations throughout the colorectal area.Abdominal computed tomography(CT)showed diffuse mural thickening of the entire colorectum,with tortuous thread-like calcifications in the right hemicolon,left hemicolon,and rectum.Most of the calcifications were located in the mesenteric vein.The diagnosis of IMP was established based on medical history,colonoscopy,CT findings,and histopathological examination.The patient was treated conservatively with papaverine and rifaximin,and CPM was stopped.Her diarrhea symptoms improved,indicating the effectiveness of the treatment.Over the next several years,she took opium alkaloids for an extended period and did not require hospitalization for the aforementioned gastrointestinal disorder.CONCLUSION IMP is a rare gastrointestinal disease affecting Asian populations,possibly related to long-term herbal medicine intake.Accurate imaging analysis is crucial for diagnosis,but insufficient understanding of the disease can lead to misdiagnosis or missed diagnosis.Treatment strategies should be personalized.

Comprehensive interventions for adult cyclic vomiting syndrome complicated by superior mesenteric artery syndrome:A case report

BACKGROUND Cyclic vomiting syndrome(CVS)is a chronic functional gastrointestinal disorder involving the gut–brain interaction that is characterized by recurring episodes of nausea,vomiting,abdominal pain,and interspersed complete normal periods.Superior mesenteric artery(SMA)syndrome(SMAS)is a vascular condition in which the horizontal portion of the duodenum is compressed due to a reduced angle between the aorta and the SMA.This condition presents with symptoms similar to CVS,posing challenges in distinguishing between the two and often resulting in misdiagnosis or inappropriate treatment.CASE SUMMARY A 20-year-old female patient presented with recurrent episodes of vomiting and experienced a persistent fear of vomiting for the past 2 years.She adopted conscious dietary restrictions,which led to severe malnutrition.Initially,she was diagnosed with SMAS,as revealed by computed tomography angiography.Despite efforts to increase the angle between the aorta and the SMA through weight gain,her vomiting did not improve.Finally,she was diagnosed with comorbidities including CVS,SMAS and anxiety disorder.She underwent comprehensive interventions,including enteral and parenteral nutritional supplementation,administration of antiemetic and anti-anxiety agents,and participation in mindfulness-based cognitive therapy.The patient eventually experienced a notable improvement in both body weight and clinical symptoms.CONCLUSION We present a rare case of CVS in an adult complicated with SMAS and propose additional treatment with nutritional support,pharmacological intervention,and psychotherapy.

Multidetector computer tomography and magnetic resonance imaging of double superior mesenteric veins:A case report

BACKGROUND This study aimed to describe the findings of double superior mesenteric veins(SMVs),a rare anatomical variation,on multidetector computer tomography(MDCT)and magnetic resonance imaging(MRI)images.CASE SUMMARY We describe the case of a 34-year-old male,who underwent both MDC and MRI examinations of the upper abdomen because of liver cirrhosis.MDCT and MRI angiography images of the upper abdomen revealed an anatomic variation of the superior mesenteric vein(SMV),the double SMVs.CONCLUSION The double SMVs are a congenital abnormality without potential clinical manifestation.Physicians need to be aware of this anatomical variation during abdominal surgery to avoid iatrogenic injury.

Simultaneous Compression of the Celiac Trunk, Superior Mesenteric Artery, and Renal Arteries by the Median Arcuate Ligament: About One Case

Median arcuate ligament syndrome (MALS), is a rare abdominal vascular compression syndrome caused by the compression of the proximal celiac trunk by the median arcuate ligament. According to many authors, a low insertion of the diaphragmatic crura or an abnormally high origin of the celiac trunk from the aorta can cause compression of the celiac artery. Usually, patients with MALS are asymptomatic. Computed tomography (CT) angiography of the abdomen is the main imaging modality to confirm the diagnosis. The coexistence of celiac trunk and superior mesenteric artery compression by the median arcuate ligament is rarely described in the literature. To our knowledge, until now, a simultaneous combination of three abdominal vascular compressions by the median arcuate ligament has never been described. From this case, we report a simultaneous compression of the celiac trunk, superior mesenteric artery, and renal arteries by the median arcuate ligament.

A surgical technique using the gastroepiploic vein for portal inflow restoration in living donor liver transplantation in a patient with diffuse portomesenteric thrombosis

Portal vein thrombosis(PVT)is no longer a definitive contraindication in liver transplants(LTs)[1].Complex vascular reconstructions such as cavoportal hemitransposition(CPHT)[2–5],renoportal anastomosis(RPA)[6,7],and use of sizable collaterals(pericholedochal varix[8,9],coronary vein,peripancreatic or perigastroesophageal varices[10],right superior colic vein[11],ileocolic vein[12],and left gastric vein[13]),or combined liverpancreas-small bowel transplant[14]are required for portal inflow in patients with total portosplenomesenteric thrombosis.

宫颈癌调强计划Portal Dosimetry剂量验证中拼接野的应用分析

目的提出一种生成Portal Dosimetry(以下简称PD)分野的拼接野(以下简称PD拼接野)方法,并对宫颈癌计划的PD拼接野进行分析研究。方法选取20例宫颈癌患者的七野调强治疗计划进行研究,治疗计划中每个大野分成1对分野。首先制作仅含分野的PD剂量验证计划,然后使用直线加速器出束执行。通过矩阵拼接和矩阵叠加,分别得到每对PD分野对应的PD拼接野和PD大野。使用PD软件模块,得到PD拼接野和PD大野的伽玛通过率,分别记为Gp和Gd。使用Gm表示每对PD分野的平均伽玛通过率值。对Gp、Gd和Gm进行统计分析和比较研究。结果所有140个射野的Gp、Gd和Gm的值分别为98.78%±0.70%、97.34%±1.25%和98.87%±0.51%。两两比较结果显示,Gp和Gd差异具有统计学意义(P<0.05);Gp和Gm的数据差异较小。对每个PD验证计划,计算所有同一类射野对应的计划验证通过率(Gplan)。对Gplan数据进行统计分析显示,PD拼接野和PD大野差异具有统计学意义(P<0.05),PD拼接野和PD分野的数据差异较小。结论本文提出的PD拼接野概念为评价PD剂量验证结果提供了有益的参考信息。

Superior mesenteric artery syndrome:Diagnosis and management

Superior mesenteric artery(SMA)syndrome(also known as Wilkie's syndrome,cast syndrome,or aorto-mesenteric compass syndrome)is an obstruction of the duodenum caused by extrinsic compression between the SMA and the aorta.The median age of patients is 23 years old(range 0-91 years old)and predominant in females over males with a ratio of 3:2.The symptoms are variable,consisting of postprandial abdominal pain,nausea and vomiting,early satiety,anorexia,and weight loss and can mimic anorexia nervosa or functional dyspepsia.Because recurrent vomiting leads to aspiration pneumonia or respiratory depression via metabolic alkalosis,early diagnosis is required.The useful diagnostic modalities are computed tomography as a standard tool and ultrasonography,which has advantages in safety and capability of real-time assessments of SMA mobility and duodenum passage.The initial treatment is usually conservative,including postural change,gastroduodenal decompression,and nutrient management(success rates:70%-80%).If conservative therapy fails,surgical treatment(i.e.,laparoscopic duodenojejunostomy)is recommended(success rates:80%-100%).

Clinical outcomes of transcatheter selective superior mesenteric artery urokinase infusion therapy vs transjugular intrahepatic portosystemic shunt in patients with cirrhosis and acute portal vein thrombosis

AIM To compare the outcomes of transcatheter superior mesenteric artery(SMA) urokinase infusion and transjugular intrahepatic portosystemic shunt(TIPS) for acute portal vein thrombosis(PVT) in cirrhosis.METHODS From January 2013 to December 2014, patients with liver cirrhosis and acute symptomatic PVT who met the inclusion criteria were randomly assigned to either an SMA group or a TIPS group. The two groups accepted transcatheter selective SMA urokinase infusion therapyand TIPS, respectively. The total follow-up time was24 mo. The primary outcome measure was the change in portal vein patency status which was evaluated by angio-computed tomography or Doppler ultrasound.Secondary outcomes were rebleeding and hepatic encephalopathy.RESULTS A total of 40 patients were enrolled, with 20 assigned to the SMA group and 20 to the TIPS group. The symptoms of all patients in the two groups improved within 48 h. PVT was improved in 17(85%) patients in the SMA group and 14(70%) patients in the TIPS group. The main portal vein(MPV) thrombosis was significantly reduced in both groups(P < 0.001), and there was no significant difference between them(P= 0.304). In the SMA group, superior mesenteric vein(SMV) thrombosis and splenic vein(SV) thrombosis were significantly reduced(P = 0.048 and P = 0.02),which did not occur in the TIPS group. At 6-, 12-,and 24-mo follow-up, in the SMA group and the TIPS group, the cumulative rates free of the first episode of rebleeding were 80%, 65%, and 45% vs 90%, 80%,and 60%, respectively(P = 0.320); the cumulative rates free of the first episode of hepatic encephalopathy were 85%, 80%, and 65% vs 50%, 40%, and 35%,respectively(P = 0.022).CONCLUSION Transcatheter selective SMA urokinase infusion and TIPS are safe and effective for acute symptomatic PVT in cirrhosis.

基于TIA Portal的HMI+PLC虚拟仿真探究

文章提出一种在TIA Portal软件上集成人机界面(Human Machine Interface,HMI)和可编程逻辑控制器(ProgrammableLogicController,PLC)进行虚拟仿真的方法。该方法能够在现有的硬件条件下,使学生不受时间、地点等的限制,只需要在计算机上安装TIA PORTAL软件就可以进行虚拟学习,构建控制系统,进行硬件组态、编程、控件组态、仿真运行和程序调试等。最后,以十字路口的交通灯为例,采用基于实际物理设备和基于TIAPORTAL软件虚拟仿真两种方式搭建控制系统,完成项目的设计、组态、编程、调试和运行测试。主要任务是寻找方法构建虚拟网络,将虚拟运行的PLC与HMI设备联系起来,实现虚拟设备之间和软件之间的数据传输,达到与使用实际物理设备效果相同的目的。