Intrahepatic portal venous systems in adult patients with cavernous transformation of portal vein: Imaging features and a new classification

Background: Cavernous transformation of the portal vein(CTPV) due to portal vein obstruction is a rare vascular anomaly defined as the formation of multiple collateral vessels in the hepatic hilum. This study aimed to investigate the imaging features of intrahepatic portal vein in adult patients with CTPV and establish the relationship between the manifestations of intrahepatic portal vein and the progression of CTPV. Methods: We retrospectively analyzed 14 CTPV patients in Beijing Tsinghua Changgung Hospital. All patients underwent both direct portal venography(DPV) and computed tomography angiography(CTA) to reveal the manifestations of the portal venous system. The vessels measured included the left portal vein(LPV), right portal vein(RPV), main portal vein(MPV) and the portal vein bifurcation(PVB). Results: Nine males and 5 females, with a median age of 40.5 years, were included in the study. No significant difference was found in the diameters of the LPV or RPV measured by DPV and CTA. The visualization in terms of LPV, RPV and PVB measured by DPV was higher than that by CTA. There was a significant association between LPV/RPV and PVB/MPV in term of visibility revealed with DPV( P = 0.01), while this association was not observed with CTA. According to the imaging features of the portal vein measured by DPV, CTPV was classified into three categories to facilitate the diagnosis and treatment. Conclusions: DPV was more accurate than CTA for revealing the course of the intrahepatic portal vein in patients with CTPV. The classification of CTPV, that originated from the imaging features of the portal vein revealed by DPV, may provide a new perspective for the diagnosis and treatment of CTPV.

Portal venous gas complication following coronary angiography:A case report

BACKGROUND Portal vein gas(PVG)is an abnormal accumulation of gas within the portal and intrahepatic portal veins.It is associated with various abdominal diseases,ranging from benign conditions to life-threatening ones that require immediate surgical intervention.Coronary angiography is the standard diagnostic procedure for coronary artery disease.There were no prior reports are available of PVG as a complication of coronary angiography.CASE SUMMARY In the specific case described here,the patient did not show signs of peritoneal irritation;however,computed tomography scans findings revealed pneumatosis in the wall of the small intestine,hepatic portal vein,and mesenteric vein,along with acute enteritis(etiology pending classification).A cesarean section was not performed,and the patient received treatment with fasting,rehydration,and antiinfection therapy.Subsequently,the patient's symptoms of abdominal distension and pain improved,and follow-up computed tomography scans indicated resolution of the portal system pneumatosis and intestinal wall edema,resulting in a favorable clinical outcome.CONCLUSION Portal venous gas complication following coronary angiography was a complication of coronary angiography.

Hepatic venous pressure gradient: Inaccurately estimates portal venous pressure gradient in alcoholic cirrhosis and portal hypertension

BACKGROUND Portal hypertension(PHT)in patients with alcoholic cirrhosis causes a range of clinical symptoms,including gastroesophageal varices and ascites.The hepatic venous pressure gradient(HVPG),which is easier to measure,has replaced the portal venous pressure gradient(PPG)as the gold standard for diagnosing PHT in clinical practice.Therefore,attention should be paid to the correlation between HVPG and PPG.METHODS Between January 2017 and June 2020,134 patients with alcoholic cirrhosis and PHT who met the inclusion criteria underwent various pressure measurements during transjugular intrahepatic portosystemic shunt procedures.Correlations were assessed using Pearson’s correlation coefficient to estimate the correlation coefficient(r)and determination coefficient(R^(2)).Bland-Altman plots were constructed to further analyze the agreement between the measurements.Disagreements were analyzed using paired t tests,and P values<0.05 were considered statistically significant.RESULTS In this study,the correlation coefficient(r)and determination coefficient(R2)between HVPG and PPG were 0.201 and 0.040,respectively(P=0.020).In the 108 patients with no collateral branch,the average wedged hepatic venous pressure was lower than the average portal venous pressure(30.65±8.17 vs.33.25±6.60 mmHg,P=0.002).Hepatic collaterals were identified in 26 cases with balloon occlusion hepatic venography(19.4%),while the average PPG was significantly higher than the average HVPG(25.94±7.42 mmHg vs 9.86±7.44 mmHg;P<0.001).The differences between HVPG and PPG<5 mmHg in the collateral vs no collateral branch groups were three cases(11.54%)and 44 cases(40.74%),respectively.CONCLUSION In most patients,HVPG cannot accurately represent PPG.The formation of hepatic collaterals is a vital reason for the strong underestimation of HVPG.

Predicting portal venous anomalies by left-sided gallbladder or rightsided ligamentum teres hepatis: A large scale, propensity scorematched study

BACKGROUND Right-sided ligamentum teres(RSLT)is often associated with portal venous anomalies(PVA)and is regarded as a concerning feature for hepatobiliary intervention.Most studies consider RSLT to be one of the causes of left-sided gallbladder(LGB),leading to the hypothesis that LGB must always be present with RSLT.However,some cases have shown that right-sided gallbladder(RGB)can also be present in livers with RSLT.AIM To highlight the rare variation that RSLT may not come with LGB and to determine whether ligamentum teres(LT)or gallbladder location is reliable to predict PVA.METHODS This study retrospectively assessed 8552 contrast-enhanced abdominal computed tomography examinations from 2018 to 2021[4483 men,4069 women;mean age,59.5±16.2(SD)years].We defined the surrogate outcome as major PVAs.The cases were divided into 4 subgroups according to gallbladder and LT locations.On one hand,we analyzed PVA prevalence by LT locations using gallbladder location as a controlled variable(n=36).On the other hand,we controlled LT location and computed PVA prevalence by gallbladder locations(n=34).Finally,we investigated LT location as an independent factor of PVA by using propensity score matching(PSM)and inverse probability of treatment weighting(IPTW).RESULTS We found 9 cases of RSLT present with RGB.Among the LGB cases,RSLT is associated with significantly higher PVA prevalence than typical LT[80.0%vs 18.2%,P=0.001;OR=18,95%confidence interval(CI):2.92-110.96].When RSLT is present,we found no statistically significant difference in PVA prevalence for RGB and LGB cases(88.9%vs 80.0%,P>0.99).Both PSM and IPTW yielded balanced cohorts in demographics and gallbladder locations.The RSLT group had a significantly higher PVA prevalence after adjusted by PSM(77.3%vs 4.5%,P<0.001;OR=16.27,95%CI:2.25-117.53)and IPTW(82.5%vs 4.7%,P<0.001).CONCLUSION RSLT doesn't consistently coexist with LGB.RSLT can predict PVA independently while the gallbladder location does not serve as a sufficient predictor.

Hepatic portal venous gas: Physiopathology, etiology, prognosis and treatment

Hepatic portal venous gas (HPVG), an ominous radiologic sign, is associated in some cases with a severe underlying abdominal disease requiring urgent operative intervention. HPVG has been reported with increasing frequency in medical literature and usually accompanies severe or lethal conditions. The diagnosis of HPVG is usually made by plain abdominal radiography, sonography, color Doppler flow imaging or computed tomography (CT) scan. Currently, the increased use of CT scan and ultrasound in the inpatient setting allows early and highly sensitive detection of such severe illnesses and also the recognition of an increasing number of benign and non-life threatening causes of HPVG. HPVG is not by itself a surgical indication and the treatment depends mainly on the underlying disease. The prognosis is related to the pathology itself and is not influenced by the presence of HPVG. Based on a review of the literature, we discuss in this paper the pathophysiology, risk factors, radiographic findings, management, and prognosis of pathologies associated with HPVG.

Portal venous arterialization resulting in increased portal inflow and portal vein wall thickness in rats

AIM： To explore the influence of portal vein hemodynamic changes after portal venous arterialization （PVA） on peribiliary vascular plexus （PVP） morphological structure and hepatic pathology, and to establish a theoretical basis for the clinical application of PVA. METHODS： Sprague-Dawley rats were randomly divided into control and PVA groups. After PVA, hemodynamic changes of the portal vein and morphological structure of hepatohilar PVP were observed using Doppler ultrasound, liver function tests, ink perfusion transparency management and three-dimensional reconstruction of computer microvisualization, and pathological examination was performed on tissue from the bile duct wall and the liver. RESULTS： After PVA, the cross-sectional area and blood flow of the portal vein were increased, and the increase became more significant over time, in a certain range. If the measure to limit the flow in PVA was not adopted, the high blood flow would lead to dilatation of intrahepatic portal vein and its branches, increase in collagen and fiber degeneration in tunica intima. Except glutamic pyruvic transaminase （GPT）, other liver function tests were normal. CONCLUSION： Blood with a certain flow and oxygen content is important for filling the PVP and meeting the oxygen requirement of the bile duct wall. After PVA, It is the anatomic basis to maintain normal morphology of hepatohilar bile duct wall that the blood with high oxygen content and high flow in arterialized portal vein may fill PVP by collateral vessel reflux. A adequate measure to limit blood flow is necessary in PVA.

Radiation therapy for portal venous invasion by hepatocellular carcinoma

AIM： To darify bhe efficacy and safety of bhree-dimensional conformal radiotherapy （3-D CRT） for bhis disease and to specify patient subgroups suitable for this treatment. METHODS： Fifty-two patients with HCC received PVItargeted radiation therapy from .January 1995 through December 2003. Portal venous invasion （PVI） was found in the second or lower order branches of the portal vein in 6 patients, in the first branch in 24 patients and in the main trunk in 22 patients. Child classifications of liver function before radiation therapy were A, B, and C for 19, 24 and 2 patients, respectively. All patients received three-dimensional conformal radiotherapy with a total dose ranging from 39 to 60 Gy （57.0 Gy in average）. RESULTS： Overall survival rates at 1, 2, 3, 4, and 5 years were 45.1%, 25.3%, 15.2%, 10.1%, and 5.1%, respectively. Univariate analysis revealed that Child status, the number of tumor foci, tumor type, transcatheter arterial embolization （TAE） after radiation therapy were statistically significant prognostic factors. Multivariate analysis showed that the number of tumor foci and TAE after radiation therapy were statistically significant. CONCLUSION： The results of this study strongly suggest the efficacy of 3-D CRT as treatment for PVI in HCC. 3-D CRT is recommended in combination with postradiation TAE for PVI of HCC with 5 tumor foci or less in the liver and with Child A liver function.

Portal vein thrombosis: Etiology and clinical outcome of cirrhosis and malignancy-related non-cirrhotic, non-tumoral extrahepatic portal venous obstruction

The etiology and pathogenesis of portal vein thrombosis are unclear. Portal venous thrombosis presentation differs in cirrhotic and tumor-related versus non-cirrhotic and non-tumoral extrahepatic portal venous obstruction (EHPVO). Non-cirrhotic and non-tumoral EHPVO patients are young and present with well tolerated bleeding. Cirrhosis and tumor-related portal vein thrombosis patients are older and have a grim prognosis. Among the 118 patients with portal vein thrombosis, 15.3% had cirrhosis, 42.4% had liver malignancy (primary or metastatic), 6% had pancreatitis (acute or chronic), 5% had hypercoagulable state and 31.3% had idiopathy, 12% had hypercoagulable state in the EHPVO group.

Portal venous gas and thrombosis in a Chinese patient with fulminant Crohn’s colitis: A case report with literature review

Ever since its earliest reports, portal venous gas (PVG) has been associated with numerous intraabdominal catastrophes and has served as an indication for urgent surgical exploration. It is traditionally regarded to be an ominous finding of impending death, with highest mortality reported in patients with underlying bowel ischemia. Today, computed tomography has demonstrated a wider range of clinical conditions associated with PVG, some of which are ‘benign’ and do not necessarily require surgery, unless when there are signs of intraabdominal catastrophe or systemic toxicity. One of these ‘benign’ conditions is Crohn’s disease. The present report describes a 19-year-old Chinese boy with Crohn’s pancolitis who presented with septic shock associated with PVG and portal vein thrombosis, and was successfully managed surgically. To our knowledge, this is the fi rst report of PVG and portal vein thrombosis associated with Crohn’s disease in a Chinese patient. In addition, we have also reviewed the reports of another 18 Crohn’s patients with PVG previously described in the English literature. Specifi c predisposing factors for PVG were identified in 8 patients, including barium enema, colonoscopy, blunt abdominal trauma, and enterovenous f istula. The patients who developed PVG following barium enema and blunt trauma were all asymptomatic and no specifi c treatment was necessary. Eleven patients (58%) who presented with signs of intraabdominal catastrophe or systemic toxicity required either immediate or eventual surgery. The overall mortality rate among the 19 patients was only 11%. The present literature review has shown that the f inding of PVG associated with Crohn’ s disease does not always mandate surgical intervention. It is the clinical features and the related complications that ultimately determine the treatment approaches. The overall outcome of PVG associated with Crohn’s disease has been favourable.

Establishment of a pig model with enteric and portal venous drainage of pancreatoduodenal transplantation

AIM： To establish the pig model of pancreatoduodena transplantation with enteric drainage （ED） and porta venous drainage （PVD）. METHODS： Forty-six hybrid Landrace pigs were divided into two groups （donors and recipients） randomly, and pancreatoduodenal allotransplantation was performed. Donors were perfused via abdominal aorta without clamping the portal venous outflow with UW solution at 80-100 cm H2O after heparinization. Whole pancreatoduodenal grafts were harvested with segments of abdominal aorta and portal vein, and shaped under 4℃ UW solution. Then, end-to-end anastomosis was performed with the donor iliac artery bifurcation Y graft to the recipient superior mesenteric artery and celiac artery. Furthermore, type I diabetes model was made by removal of the recipient pancreas. The venous anastomosis was reconstructed between the donor portal vein and the recipient superior mesentery vein. Meanwhile, end-toside anastomosis was performed with the donor common iliac artery bifurcation Y graft to the recipient abdominal aorta, and side-to-side intestinal anastomosis was performed between the donor duodenum and the recipient jejunum. External jugular vein was intubated for transfusion. Levels of plasma glucose, insulin and glucagon were measured during the operation and on the 1^st 3^rd 5^th and 7^th d after operation. RESULTS： Pancreatoduodenal allotransplantation was performed on 23 pigs of which 1 died of complication of anesthesia. The success rate of operation was 95.6%. Complications of operation occurred in two cases in which one was phlebothrombosis with an incidence of 4.6%, and the other was duodenojejunal anastomotic leak with an incidence of 4.6%. The level of plasma glucose decreased within 30 min, after removal of pancreas and recovered on the 2^nd after operation. The level of plasmainsulin and glucagon increased within 30 min after removal of pancreas and recovered on the 2^nd d after operation. Rejection occurred on the 1^st and reached the worst level on the 7^th d after transplantation, without change of plasma insulin and glucagon or clinical symptoms of rejection. CONCLUSION： Pancreatoduodenal transplantation in pigs can treat type I diabetes. ED and PVD can keep the function of endocrine in normal. The technique of pancreatoduodenal transplantation with ED and PVD may pave the way for the further application of pancreas transplantation in clinic.

Hepatic portal venous gas in pancreatic solitary metastasis from an esophageal squamous cell carcinoma

BACKGROUND:Hepatic portal venous gas(HPVG) is a rare entity commonly associated with intestinal necrosis and fatal outcome,and various underlying diseases have been reported.Pancreatic solitary metastasis without local extension is also rare in esophageal squamous cell carcinoma.METHODS:This report describes an interesting and unusual case of HPVG arising from pancreatic tumor.Autopsy revealed pathogenesis of HPVG and synchronous tumors of the esophagus and pancreas.RESULTS:A 73-year-old man developed synchronous double tumor in the esophagus and pancreas several months before acute abdomen and his death,which were generated by HPVG.Autopsy revealed that HPVG was caused by gastric wall infarction owing to expansion of an isolated pancreatic metastasis from esophageal squamous cell carcinoma.CONCLUSIONS:This is the first case of HPVG that was derived from pancreatic tumor infiltration.If he had been diagnosed with solitary pancreatic metastasis from esophageal squamous cell carcinoma in the first time,he might have an option for chemotherapy,which could let him live longer.

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.

Preoperative application of combination of portal venous injection of donor spleen cells and intraperitoneal injection of rapamycin prolongs the survival of cardiac allografts in mice

Objective:To investigate the effects of preoperative portal venous injection of donor spleen cells(PVIDSC) and intraperitoneal injection of rapamycin in the acute rejection of cardiac allograft in mice and the underlying mechanisms. Methods:Homogenous female B6 mice and BALB/c mice were used as recipients and donors of heart transplantation. These mice were randomly divided into different groups and received PVIDSC alone,rapamycin alone,or PVIDSC and rapamycin combined therapy. In addition,the underlying mechanism was studied by measuring a number of cytokines. Results:Preoperative combination of PVIDSC and intraperitoneal injection of rapamycin significantly prolonged the survival of heterotopic cardiac allograft in mice,but had no effects on the survival time of cardiac allografts in mice pre-sensitized by skin grafting. Preoperative combination of PVIDSC and intraperitoneal injection of rapamycin increased the expression of IL-10 and Foxp3 and reduced the expression of INF-γ. Short-term preoperative administration of rapamycin promotes the expression of CD4^+CD25^+Foxp3^+ regulator T cells. However,preoperative using alone of rapamycin,or combination of PVIDSC and rapamycin had no effects on the inhibition of proliferation of memory T cells. Conclusions:Preoperative application of combination of PVIDSC and rapamycin significantly prolonged the survival time of cardiac allografts in mice but not in mice pre-sensitized by skin grafting. This may be explained by the fact that combination of PVIDSC and rapamycin inhibited the cellular immune response and induced the expression of IL-10 from Tr1 cells and CD4^+CD25^+FoxP3^+ regulatory T cells.

Hepatic portal venous gas without definite clinical manifestations of necrotizing enterocolitis in a 3-day-old full-term neonate:A case report

BACKGROUND Neonatal hepatic portal venous gas(HPVG)is associated with a high risk of necrotizing enterocolitis(NEC)and was previously believed to be associated with an increased risk of surgery.CASE SUMMARY A 3-day-old full-term male infant was admitted to the pediatrics department after presenting with"low blood glucose for 10 min".Hypoglycemia was corrected by intravenous glucose administration and oral breast milk.On the 3rd d after admission,an ultrasound examination showed gas accumulation in the hepatic portal vein;this increased on the next day.Abdominal vertical radiograph showed intestinal pneumatosis.Routine blood examination showed that the total number of white blood cells was normal,but neutrophilia was related to age.There was a significant increase in C-reactive protein(CRP).The child was diagnosed with neonatal NEC(early-stage).With nil per os,rehydration,parenteral nutritional support,and anti-infection treatment with no sodium,his hepatic portal vein pneumatosis resolved.In addition,routine blood examination and CRP examination showed significant improvement and his symptoms resolved.The patient was given timely refeeding and gradually transitioned to full milk feeding and was subsequently discharged.Follow-up examination after discharge showed that the general condition of the patient was stable.CONCLUSION The presence of HPVG in neonates indicates early NEC.Early active anti-infective treatment is effective in treating NEC,minimizes the risk of severe NEC,and reduces the need for surgery.The findings of this study imply that early examination of the liver by ultrasound in a sick neonate can help with the early diagnosis of conditions such as NEC.

Portal biliopathy

Biliary ductal changes are a common radiological finding in patients with portal hypertension, however only a small percentage of patients (5%-30%) develop symptomatic bile duct obstruction. The exact pathogenesis is not clear, but an involvement of factors such as bile duct compression by venous collaterals, ischemia, and infection is accepted by most authors. Although endoscopic retrograde cholangiopancrea- tography was used to define and diagnose this condition, magnetic resonance cholangiopancreatography is currently the investigation of choice for diagnosing this condition. Treatment is indicated only for symptomatic cases. Portosystemic shunts are the treatment of choice for symptomatic portal biliopathy. In the majority of patients, the changes caused by biliopathy resolve after shunt surgery, however, 15%-20% patients require a subsequent bilio-enteric bypass or endoscopic management for persistent biliopathy. There is a role for endoscopic therapy in patients with bile duct stones, cholangitis or when portosystemic shunt surgery is not feasible.

Portal biliopathy

Portal biliopathy refers to cholangiographic abnormalities which occur in patients with portal cavernoma. These changes occur as a result of pressure on bile ducts from bridging tortuous paracholedochal, epicholedochal and cholecystic veins. Bile duct ischemia may occur due prolonged venous pressure effect or result from insufficient blood supply. In addition, encasement of ducts may occur due fibrotic cavernoma. Majority of patients are asymptomatic. Portal biliopathy is a progressive disease and patients who have long standing disease and more severe bile duct abnormalities present with recurrent episodes of biliary pain, cholangitis and cholestasis. Serum chemistry, ultrasound with color Doppler imaging, magnetic resonance imaging with magnetic resonance cholangiopancreatography and magnetic resonance portovenography are modalities of choice for evaluation of portal biliopathy. Endoscopic retrograde cholangiography being an invasive procedure is indicated for endotherapy only. Management of portal biliopathy is done in a stepwise manner. First, endotherapy is done for dilation of biliary strictures, placement of biliary stents to facilitate drainage and removal of bile duct calculi. Next portal venous pressure is reduced by formation of surgical porto-systemic shunt or transjugular intrahepatic portosystemic shunt. This causes significant resolution of biliary changes. Patients who persist with biliary symptoms and bile duct changes may benefit from surgical biliary drainage procedures(hepaticojejunostomy or choledechoduodenostomy).

A new choice of stent for transjugular intrahepatic portosystemic shunt creation: Viabahn ePTFE covered stent/bare metal stent combination

Objectives:To compare the clinical outcomes in terms of structure and function between the insertion of a transjugular intrahepatic portosystemic shunt(TIPS) created with the Viabahn ePTFE covered stent/bare metal stent(BMS) combination and the Fluency ePTFE covered stent/BMS combination.Methods:A total of 101 consecutive patients who received a TIPS from February 2016 to August 2018 in our center were retrospectively analyzed.Sixty-four subjects were enrolled in the Viabahn group and 37 were enrolled in the Fluency group.The geometry characteristics of the TIPS were calculated,and the associated occurrence of shunt dysfunction,survival,overt hepatic encephalopathy,and variceal rebleeding were evaluated.Results:The technical success rate was 100%.After the insertion of the TIPS,the rate of shunt dysfunction during the first 3 months was significantly different between the Viabahn and Fluency groups(1.6% and 13.5%,respectively;p=0.024).Multivariate analysis indicated that the angle of portal venous inflow(α) was the only independent risk factor for shunt dysfunction(hazard ratio=1.060,95% confidence interval=1.009-1.112,p=0.020).In addition,3 months after the TIPS insertion,the a angle distinctly increased from 20.9°±14.3°-26.9°±20.1°(p=0.005) in the Fluency group but did not change significantly in the Viabahn group(from 21.9°±15.1°-22.9°± 17.6°,p=0.798).Conclusions:Shunt dysfunction was related to the a angle owing to the slight effect on the a angle after the implantation of the TIPS.The Viabahn ePTFE covered stent/BMS combination was more stable in structure and promised higher short-term stent patency compared with the Fluency ePTFE covered stent/BMS combination.

Enterovenous fistulization: A rare complication of Crohn's disease

The presence of hepatic portal venous gas (HPVG) is associated with numerous diseases, and has been regarded as a serious, even catastrophic condition. However, anecdotal reports mention that some patients with inflammatory bowel disease (IBD), who developed HPVG after diagnostic examinations of the colon, were successfully managed with antibiotic therapy and have followed benign courses. In contrast, among IBD patients, the development of HPVG is rarely caused by enterovenous fistula. We describe a 32-year-old man with Crohn's ileocolitis who presented with hypotension and fever associated with HPVG, as well as superior mesenteric vein thrombosis, possibly caused by enterovenous fistula, who was successfully managed by surgery. We also review the literature concerning portal venous gas associated with Crohn's disease.

Percutaneous transhepatic portal catheterization guided by ultrasound technology for islet transplantation in rhesus monkey

BACKGROUND:Pig islet xenotransplantation has the potential to overcome the shortage of donated human islets for islet cell transplantation in type 1 diabetes.Testing in nonhuman primate models is necessary before clinical application in humans.Intraportal islet transplantation in monkeys is usually performed by surgical infusion during laparotomy or laparoscopy.In this paper,we describe a new method of percutaneous transhepatic portal catheterization(PTPC) as an alternative to current methods of islet transplantation in rhesus monkeys.METHODS:We performed ultrasound-guided PTPC in five adult rhesus monkeys weighing 7-8 kg,with portal vein catheterization confirmed by digital subtraction angiography.We monitored for complications in the thoracic and abdominal cavity.To evaluate the safety of ultrasound-guided PTPC,we recorded the changes in portal pressure throughout the microbead transplantation procedure.RESULTS:Ultrasound-guided PTPC and infusion of 16 000 microbeads/kg body weight into the portal vein was successful in all five monkeys.Differences in the hepatobiliary anatomy of rhesus monkeys compared to humans led to a higher initial complication rate.The first monkey died of abdominal hemorrhage 10 hours post-transplantation.The second suffered from a mild pneumothorax but recovered fully after taking only conservative measures.After gaining experience with the first two monkeys,we decreased both the hepatic puncture time and the number of puncture attempts required,with the remaining three monkeys experiencing no complications.Portal pressures initially increased proportional to the number of transplanted microbeads but returned to preinfusion levels at 30 minutes post-transplantation.The changes in portal pressures occurring during the procedure were not significantly different.CONCLUSIONS:Ultrasound-guided PTPC is an effective,convenient,and minimally invasive method suitable for use in non-human primate models of islet cell transplantation provided that care is taken with hepatic puncture.Its advantages must be weighed against the risks of procedure-related complications.

The spectrum of pneumatosis intestinalis in the adult.A surgical dilemma

Pneumatosis intestinalis(PI) is a striking radiological diagnosis. Formerly a rare diagnostic finding, it is becoming more frequently diagnosed due to the wider availability and improvement of computed tomography scan imaging. Once associated only with poor outcome, its clinical and prognostic significance nowadays has to be cross-referenced to the nature of the underlying condition.Multiple mechanisms of pathogenesis have been debated and multiple causes have been detected during the years. All this contributes to creating a broad range of clinical and radiological presentations. The management of patients presenting PI is related to the determining cause if it is identified. Otherwise, in particular if an association with portal venous gas and/or pneumoperitoneum is present, the eventual decision between surgery and non-operative management is challenging,even for stable patients, since this clinical condition is traditionally associated to intestinal ischemia and consequently to pending clinical collapse if not treated.Considering the wide variety of origin and outcomes, PI still remains for surgeons a demanding clinical entity. The manuscript is an updated narrative review and gives some suggestions that may help make the decisional process easier,identifying patients who can benefit from surgical intervention and those who can benefit from non-operative management avoiding unnecessary procedures.