Special considerations in the management of lower GI bleed by interventional radiology

Despite the rapid development of diagnostic and therapeutic modalities and techniques to manage LGIB patients from interventional radiology’s standpoint,a successful localization of the bleeding site that leads to an effective embolotherapy remains a significant technical challenge.The interventional radiologist’s decisions when managing patients with LGIB may significantly impact the clinical outcomes;therefore,management should be made based on careful and thorough considerations of factors such as etiology,locations,patient’s comorbidities,and potential post-procedure complications,among others.The purpose of this paper is to review the management of LGIB by interventional radiology,focusing on a few challenging and common clinical situations that require special consideration by interventional radiologists.

The Journey of Interventional Radiology in China

The first balloon angioplasty performed by Dr.Charles T.Dotter in 1964 marked the birth of a new discipline in radiology(1),which was initially named'interventional diagnostic radiology'by Dr.Alexander R.Margulis in 1967(2),and later defined as'Interventional Radiology(IR)'by Dr.Sidney Wallace in 1976(3).Along with the wide adaptation of Seldinger’s technique for percutaneous vascular access(4),interventional radiology expanded the horizon of traditional radiology.

Complementary roles of interventional radiology and therapeutic endoscopy in gastroenterology

Acute upper and lower gastrointestinal bleeding, enteral feeding, cecostomy tubes and luminal strictures are some of the common reasons for gastroenterology service. While surgery was initially considered the main treatment modality, the advent of both therapeutic endoscopy and interventional radiology have resulted in the paradigm shift in the management of these conditions. In this paper, we discuss the patient's work up, indications, and complementary roles of endoscopic and angiographic management in the settings of gastrointestinal bleeding, enteral feeding, cecostomy tube placement and luminal strictures. These conditions often require multidisciplinary approaches involving a team of interventional radiologists, gastroenterologists and surgeons. Further, the authors also aim to describe how the fields of interventional radiology and gastrointestinal endoscopy are overlapping and complementary in the management of these complex conditions.

Extravasated contrast volumetric assessment on computed tomography angiography in gastrointestinal bleeding:A useful predictor of positive angiographic findings

BACKGROUND Gastrointestinal bleeding(GIB)is a severe and potentially life-threatening condition,especially in cases of delayed treatment.Computed tomography angiography(CTA)plays a pivotal role in the early identification of upper and lower GIB and in the prompt treatment of the haemorrhage.AIM To determine whether a volumetric estimation of the extravasated contrast at CTA in GIB may be a predictor of subsequent positive angiographic findings.METHODS In this retrospective single-centre study,35 patients(22 men;median age 69 years;range 16-92 years)admitted to our institution for active GIB detected at CTA and further submitted to catheter angiography between January 2018 and February 2022 were enrolled.Twenty-three(65.7%)patients underwent endoscopy before CTA.Bleeding volumetry was evaluated in both arterial and venous phases via a semi-automated dedicated software.Bleeding rate was obtained from volume change between the two phases and standardised for unit time.Patients were divided into two groups,according to the angiographic signs and their concordance with CTA.RESULTS Upper bleeding accounted for 42.9%and lower GIB for 57.1%.Mean haemoglobin value at the admission was 7.7 g/dL.A concordance between positive CTA and direct angiographic bleeding signs was found in 19(54.3%)cases.Despite no significant differences in terms of bleeding volume in the arterial phase(0.55 mL vs 0.33 mL,P=0.35),a statistically significant volume increase in the venous phase was identified in the group of patients with positive angiography(2.06 mL vs 0.9 mL,P=0.02).In the latter patient group,a significant increase in bleeding rate was also detected(2.18 mL/min vs 0.19 mL/min,P=0.02).CONCLUSION In GIB of any origin,extravasated contrast volumetric analysis at CTA could be a predictor of positive angiography and may help in avoiding further unnecessary procedures.

Evidence-based medical oncology and interventional radiology paradigms for liver-dominant colorectal cancer metastases

Colorectal cancer metastasizes predictably, with liver predominance in most cases. Because liver involvement has been shown to be a major determinant of survival in this population, liver-directed therapies are increasingly considered even in cases where there is(limited) extrahepatic disease. Unfortunately, these patients carry a known risk of recurrence in the liver regardless of initial therapy choice. Therefore, there is a demand for minimally invasive, non-surgical, personalized cancer treatments to preserve quality of life in the induction, consolidation, and maintenance phases of cancer therapy. This report aims to review evidence-based conceptual, pharmacological, and technological paradigm shifts in parenteral and percutaneous treatment strategies as well as forthcoming evidence regarding next-generation systemic, locoregional, and local treatment approaches for this patient population.

Liver involvement in patients with COVID-19 infection:A comprehensive overview of diagnostic imaging features

During the first wave of the pandemic,coronavirus disease 2019(COVID-19)infection has been considered mainly as a pulmonary infection.However,different clinical and radiological manifestations were observed over time,including involvement of abdominal organs.Nowadays,the liver is considered one of the main affected abdominal organs.Hepatic involvement may be caused by either a direct damage by the virus or an indirect damage related to COVID-19 induced thrombosis or to the use of different drugs.After clinical assessment,radiology plays a key role in the evaluation of liver involvement.Ultrasonography(US),computed tomography(CT)and magnetic resonance imaging(MRI)may be used to evaluate liver involvement.US is widely available and it is considered the first-line technique to assess liver involvement in COVID-19 infection,in particular liver steatosis and portal-vein thrombosis.CT and MRI are used as second-and third-line techniques,respectively,considering their higher sensitivity and specificity compared to US for assessment of both parenchyma and vascularization.This review aims to the spectrum of COVID-19 liver involvement and the most common imaging features of COVID-19 liver damage.

Fracture of inferior vena cava stent after endovascular treatment for Budd-Chiari syndrome:A case series and literature review

Budd-Chiari syndrome(BCS)is a rare condition characterized by hepatic venous outflow obstruction.Balloon angioplasty,with or without stenting,is the recommended first-line treatment modality in Asian countries.As a supplement to balloon angioplasty,expandable metallic Z-stent deployment can effectively improve long-term inferior vena cava(IVC)patency.Although stent placement is a standard and frequently performed treatment,very few IVC stent-related complications,such as stent fractures,have been reported.Here we present a case series and a comprehensive review of IVC stent fractures in patients with BCS.The most common characteristic of IVC stent fractures is a protrusion of the proximal segment of the IVC stent into the right atrium and its systolic and diastolic movements along with heart rhythms.Accurate stent deployment,large-diameter balloon dilation,patient breath-holding training,preferential selection of a triple stent,and the use of an internal jugular vein approach to stent deployment may ensure precise stent localization and avoid postoperative complications.

MR with Gd-EOB-DTPA in assessment of liver nodules in cirrhotic patients

To date the imaging diagnosis of liver lesions is based mainly on the identification of vascular features, which are typical of overt hepatocellular carcinoma(HCC), but the hepatocarcinogenesis is a complex and multistep event during which, a spectrum of nodules develop within the liver parenchyma, including benign small and large regenerative nodule(RN), low-grade dysplastic nodule(LGDN), high-grade dysplastic nodule(HGDN), early HCC, and well differentiated HCC. These nodules may be characterised not only on the basis of their respective different blood supplies, but also on their different hepatocyte function. Recently, in liver imaging the introduction of hepatobiliary magnetic resonance imaging contrast agent offered the clinicians the possibility to obtain, at once, information not only related to the vascular changes of liver nodules but also information on hepatocyte function. For this reasons this new approach becomes the most relevant diagnostic clue for differentiating low-risk nodules(LGDN-RN) from highrisk nodules(HGDN/early HCC or overt HCC) and consequently new diagnostic algorithms for HCC have been proposed. The use of hepatobiliary contrast agents is constantly increasing and gradually changing the standard of diagnosis of HCC. The main purpose of this review is to underline the added value of Gd-EOB-DTPA in early-stage diagnoses of HCC. We also analyse the guidelines for the diagnosis and management of HCC, the key concepts of HCC development, growth and spread and the imaging appearance of precursor nodules that eventually may transform into overt HCC.

Recent advances in non-invasive magnetic resonance imaging assessment of hepatocellular carcinoma

Magnetic resonance(MR) imaging of the liver is an important tool for the detection and characterization of focal liver lesions and for assessment of diffuse liver disease,having several intrinsic characteristics,represented by high soft tissue contrast,avoidance of ionizing radiation or iodinated contrast media,and more recently,by application of several functional imaging techniques(i.e.,diffusion-weighted sequences,hepatobiliary contrast agents,perfusion imaging,magnetic resonance(MR)-elastography,and radiomics analysis). MR functional imaging techniques are extensively used both in routine practice and in the field of clinical and pre-clinical research because,through a qualitative rather than quantitative approach,they can offer valuable information about tumor tissue and tissue architecture,cellular biomarkers related to the hepatocellular functions,or tissue vascularization profiles related to tumor and tissue biology. This kind of approach offers in vivo physiological parameters,capable of evaluating physiological and pathological modifications of tissues,by the analysis of quantitative data that could be used in tumor detection,characterization,treatmentselection,and follow-up,in addition to those obtained from standard morphological imaging. In this review we provide an overview of recent advanced techniques in MR for the diagnosis and staging of hepatocellular carcinoma,and their role in the assessment of response treatment evaluation.

Passive expansion of sub-maximally dilated transjugular intrahepatic portosystemic shunts and assessment of clinical outcomes

AIM To assess for passive expansion of sub-maximally dilated transjugular intrahepatic portosystemic shunts(TIPS) and compare outcomes with maximally dilated TIPS.METHODS Polytetrafluoroethylene covered TIPS(Viatorr) from July 2002 to December 2013 were retrospectively reviewed at two hospitals in a single institution. Two hundred and thirty patients had TIPS maximally dilated to 10 mm(m TIPS), while 43 patients who were at increased risk for hepatic encephalopathy(HE), based on clinical evaluation or low pre-TIPS portosystemic gradient(PSG), had 10 mm TIPS sub-maximally dilated to 8 mm(sm TIPS). Group characteristics(age, gender, Model for End-Stage Liver Disease score, post-TIPS PSG and clinical outcomes were compared between groups, including clinical success(ascites or varices), primary patency,primary assisted patency, and severe post-TIPS HE. A subset of fourteen patients with sm TIPS underwent follow-up computed tomography imaging after TIPS creation, and were grouped based on time of imaging(< 6 mo and > 6 mo). Change in diameter and crosssectional area were measured with 3D imaging software to evaluate for passive expansion.RESULTS Patient characteristics were similar between the sm TIPS and m TIPS groups, except for pre-TIPS portosystemic gradient, which was lower in the sm TIPS group(19.4 mm Hg ± 6.8 vs 22.4 mm Hg ± 7.1, P = 0.01). Primary patency and primary assisted patency between sm TIPS and m TIPS was not significantly different(P = 0.64 and 0.55, respectively). Four of the 55 patients(7%) with sm TIPS required TIPS reduction for severe refractory HE, while this occurred in 6 of the 218 patients(3%) with m TIPS(P = 0.12). For the 14 patients with follow-up computed tomography(CT) imaging, the median imaging follow-up was 373 d. There was an increase in median TIPS diameter, median percent diameter change, median area, and median percent area change in patients with CT follow-up greater than 6 mo after TIPS placement compared to follow-up within 6 mo(8.45 mm, 5.58%, 56.04 mm^2, and 11.48%, respectively, P = 0.01).CONCLUSION Passive expansion of sm TIPS does occur but clinical outcomes of sm TIPS and m TIPS were similar. Sub-maximal dilation can prevent complications related to overshunting in select patients.

Portal hypertension: Imaging of portosystemic collateral pathways and associated image-guided therapy

Portal hypertension is a common clinical syndrome, defined by a pathologic increase in the portal venous pressure. Increased resistance to portal blood flow, the primary factor in the pathophysiology of portal hypertension, is in part due to morphological changes occurring in chronic liver diseases. This results in rerouting of blood flow away from the liver through collateral pathways to low-pressure systemic veins. Through a variety of computed tomographic, sonographic, magnetic resonance imaging and angiographic examples, this article discusses the appearances and prevalence of both common and less common portosystemic collateral channels in the thorax and abdomen. A brief overview of established interventional radiologic techniques for treatment of portal hypertension will also be provided. Awareness of the various imaging manifestations of portal hypertension can be helpful for assessing overall prognosis and planning proper management.

Nationwide trends and predictors of inpatient mortality in 83884 transjugular intrahepatic portosystemic shunt

AIM: To evaluate and validate the national trends and predictors of in-patient mortality of transjugular intrahepatic portosystemic shunt(TIPS) in 15 years.METHODS: Using the National Inpatient Sample which is a part of Health Cost and Utilization Project, we identified a discharge-weighted national estimate of 83884 TIPS procedures performed in the United States from 1998 to 2012 using international classification of diseases-9 procedural code 39.1. The demographic, hospital and co-morbility data were analyzed using a multivariant analysis. Using multi-nominal logistic regression analysis, we determined predictive factors related to increases in-hospital mortality. Comorbidity measures are in accordance to the Comorbidity Software designed by the Agency for Healthcare Research and Quality.RESULTS: Overall, 12.3% of patients died during hospitalization with downward trend in-hospitalmortality with the mean length of stay of 10.8 ± 13.1 d. Notable, African American patients(OR = 1.809 vs Caucasian patients, P < 0.001), transferred patients(OR = 1.347 vs non-transferred, P < 0.001), emergency admissions(OR = 3.032 vs elective cases, P < 0.001), patients in the Northeast region(OR = 1.449 vs West, P < 0.001) had significantly higher odds of inhospital mortality. Number of diagnoses and number of procedures showed positive correlations with in-hospital death(OR = 1.249 per one increase in number of procedures). Patients diagnosed with acute respiratory failure(OR = 8.246), acute kidney failure(OR = 4.359), hepatic encephalopathy(OR = 2.217) and esophageal variceal bleeding(OR = 2.187) were at considerably higher odds of in-hospital death compared with ascites(OR = 0.136, P < 0.001). Comorbidity measures with the highest odds of in-hospital death were fluid and electrolyte disorders(OR = 2.823), coagulopathy(OR = 2.016), and lymphoma(OR = 1.842).CONCLUSION: The overall mortality of the TIPS procedure is steadily decreasing, though the length of stay has remained relatively constant. Specific patient ethnicity, location, transfer status, primary diagnosis and comorbidities correlate with increased odds of TIPS in-hospital death.

Portal vein embolization for induction of selective hepatic hypertrophy prior to major hepatectomy: rationale,techniques, outcomes and future directions

The ability to modulate the future liver remnant(FLR) is a key component of modern oncologic hepatobiliary surgery practice and has extended surgical candidacy for patients who may have been previously thought unable to survive liver resection. Multiple techniques have been developed to augment the FLR including portal vein embolization(PVE), associating liver partition and portal vein ligation(ALPPS), and the recently reported transhepatic liver venous deprivation(LVD). PVE is a well-established means to improve the safety of liver resection by redirecting blood flow to the FLR in an effort to selectively hypertrophy and ultimately improve functional reserve of the FLR. This article discusses the current practice of PVE with focus on summarizing the large number of published reports from which outcomes based practices have been developed. Both technical aspects of PVE including volumetry, approaches, and embolization agents; and clinical aspects of PVE including data supporting indications, and its role in conjunction with chemotherapy and transarterial embolization will be highlighted. PVE remains an important aspect of oncologic care; in large part due to the substantial foundation of information available demonstrating its clear clinical benefit for hepatic resection candidates with small anticipated FLRs.

Intraoperative radiofrequency ablation with or without tumorectomy for hepatocellular carcinoma in locations difficult for a percutaneous approach

BACKGROUND:Although hepatic resection is widely accepted as a proper modality for treating hepatocellular carcinoma(HCC),a majority of patients are unable to undergo surgical resection due to various tumor and patient factors.Radiofrequency ablation(RFA)has mostly been used as a therapeutic alternative to resection for treating HCC.The objective of this study was to evaluate the results of intraoperative RFA for HCCs in locations difficult for a percutaneous approach.METHODS:Eight patients(male,seven;age,49-67 years) with 8 HCCs in difficult locations were treated by intraoperative RFA.Six of the patients had local tumor progression after initial transarterial chemoembolization or ultrasound(US)guided percutaneous RFA.The locations of the tumors were hepatic dome in six patients,posterior subcapsule in one,and caudate lobe in one.The tumor size was 2.0 to 6.4 cm(mean,3.9 cm).Intraoperative RFA was performed at the tumor itself and an anticipated resection line under US guidance with 3 cm monopolar single or clustered internally cooled electrodes.Tumor resection was performed in six patients.One month later,treatment response was assessed by contrast material-enhanced computed tomography(CT).CT studies were performed every 2 or 3 months after RFA.RESULTS:RFA was technically successful in all tumors,and the contrast-enhanced CT images acquired one month later showed complete disappearance of tumor enhancement.One pneumothorax occurred.After a median follow-up of 18 months(range,6-30 months),no tumors showed local progression.During the follow-up period,four new recurrent tumors were observed in three patients.Four patients were alive at the time of this report and the other four died of hepatorenal syndrome,liver failure,and progression of new recurrent tumors.CONCLUSION:Intraoperative RFA with tumor resection can be an alterative treatment option for HCC in locations difficult for a percutaneous approach.

Endovascular treatment of pulmonary embolism: Selective review of available techniques

Acute pulmonary embolism(PE) is the third most common cause of death in hospitalized patients. The development of sophisticated diagnostic and therapeutic modalities for PE, including endovascular therapy, affords a certain level of complexity to the treatment of patients with this important clinical entity. Furthermore, the lack of level I evidence for the safety and effectiveness of catheter directed therapy brings controversy to a promising treatment approach. In this review paper, we discuss the pathophysiology and clinical presentation of PE, review the medical and surgical treatment of the condition, and describe in detail the tools that are available for the endovascular therapy of PE, including mechanical thrombectomy, suction thrombectomy, and fibrinolytic therapy. We also review the literature available to date on these methods, and describe the function of the Pulmonary Embolism Response Team.

Effects of Yttrium-90 selective internal radiation therapy on non-conventional liver tumors

The liver is a common site of metastasis, with essentially all metastatic malignancies having been known to spread to the liver. Nearly half of all patients with extrahepatic primary cancer have hepatic metastases. The severe prognostic implications of hepatic metastases have made surgical resection an important first line treatment in management. However, limitations such as the presence of extrahepatic spread or poor functional hepatic reserve exclude the majority of patients as surgical candidates, leaving chemotherapy and locoregional therapies as next best options. Selective internal radiation therapy(SIRT) is a form of catheter-based locoregional cancer treatment modality for unresectable tumors, involving trans-arterial injection of microspheres embedded with a radioisotope Yttrium-90. The therapeutic radiation dose is selectively delivered as the microspheres permanently embed themselves within the tumor vascular bed. Use of SIRT has been conventionally aimed at treating primary hepatic tumors(hepatocellular carcinoma) or colorectal and neuroendocrine metastases. Numerous reviews are available for these tumor types. However, little is known or reviewed on non-colorectal or nonneuroendocrine primaries. Therefore, the aim of this paper is to systematically review the current literature to evaluate the effects of Yttrium-90 radioembolization on non-conventional liver tumors including those secondary to breast cancer, cholangiocarcinoma, ocular and percutaneous melanoma, pancreatic cancer, renal cell carcinoma, and lung cancer.

Gadoxetic acid magnetic-enhanced resonance imaging in the diagnosis of cholangiocarcinoma

The use of liver magnetic resonance imaging is increasing thanks to itsmultiparametric sequences that allow a better tissue characterization, and the useof hepatobiliary contrast agents. This review aims to evaluate gadoxetic acidenhanced magnetic resonance imaging in the diagnosis and staging ofcholangiocarcinoma and its different clinical and radiological classificationsproposed in the literature. We also analyze the epidemiology, risk factors incorrelation with clinical findings and laboratory data.

Giant splenic artery aneurysm presenting with massive upper gastrointestinal bleeding:A case report and review of literature

BACKGROUND Splenic artery aneurysm(SAA)and pseudoaneurysm are rare vessel’s lesions.Pseudoaneurysm is often symptomatic and secondary to pancreatitis or trauma.True SAA is the most common aneurysm of visceral vessels.In contrast to pseudoaneurysm,SAA is usually asymptomatic until the rupture,with high mortality rate.The clinical onset of SSA’s rupture is a massive life-threatening bleeding with hemodynamic instability,usually into the free peritoneal space and more rarely into the gastrointestinal tract.CASE SUMMARY We describe the case of a 35-year-old male patient,with negative past medical history,who presented to the emergency department for massive upper gastrointestinal bleeding,severe anemia and hypotension.An esophagogastroduodenoscopy performed in emergency showed a gastric bulging in the greater curvature/posterior wall with a small erosion on its surface,with a visible vessel,but no active bleeding.Endoscopic injection therapy with cyanoacrylate glue was performed.Urgent contrast-enhanced computed tomography was carried out due to the clinical scenario and the unclear endoscopic aspect:The radiological examination showed a giant SAA which was adherent to posterior stomach wall,and some smaller aneurysms of the left gastric and ileocolic artery.Because of the high risk of a two-stage rupture of the giant SAA with dramatic outcome,the patient underwent immediate open surgery with aneurysmectomy,splenectomy and distal pancreatectomy with a good postoperative outcome.CONCLUSION The management of a ruptured giant SAA into the stomach can be successful with surgical approach.

Image-guided locoregional non-intravascular interventional treatments for hepatocellular carcinoma: Current status

Hepatocellular carcinoma(HCC) is one of the most deadly and frequent cancers worldwide,although great advancement in the treatment of this malignancy have been made within the past few decades.It continues to be a major health issue due to an increasing incidence and a poor prognosis.The majority of patients have their HCC diagnosed at an intermediate or advanced stage in theUSA or China.Curative therapy such as surgical resection or liver transplantation is not considered anoption of treatment at these stages.Transarterial chemoembolization(TACE),the most widely used locoregional therapeutic approach,used to be the mainstay of treatment for cases with unresectable cancer entities.However,for those patients with hypovascular tumors or impaired liver function reserve,TACE is a suboptimal treatment option.For example,embolization does not result in complete coverage of a hypovascular tumor,and may rather promotes postoperative tumor recurrence,or leave residual tumor,in these TACE-resistance patients.In addition,TACE carries a higher risk of hepatic decompensation in patients with poor liver function or reserve.Non-vascular interventional locoregional therapies for HCC include radiofrequency ablation(RFA),microwave ablation(MWA),high-intensity focused ultrasound(HIFU),laser-induced thermotherapy(LITT),cryosurgical ablation(CSA),irreversible Electroporation(IRE),percutaneous ethanol injection(PEI),and brachytherapy.Recent advancements in these techniques have significantly improved the treatment efficacy of HCC and expanded the population of patients who qualify for treatment.This review embraces the current status of imaging-guided locoregional non-intravascular interventional treatments for HCCs,with a primary focus on the clinical evaluation and assessment of the efficacy of combined therapies using these interventional techniques.

Endovascular treatment of aortoiliac aneurysms: From intentional occlusion of the internal iliac artery to branch iliac stent graft

Approximately 20%-40% of patients with abdominal aortic aneurysms can have unilateral or bilateral iliac artery aneurysms and/or ectasia. This influences and compromises the distal sealing zone during endovascular aneurysm repair. There are a few endovascular techniques that are used to treat these types of aneurysms, including intentional occlusion/over-stenting of the internal iliac artery on one or both sides, the "bell-bottom" technique, and the more recent method of using an iliac branch stent graft. In some cases, other options include the "snorkel and sandwich" technique and hybrid interventions. Pelvic ischemia, represented as buttock claudication, has been reported in 16%-55% of cases; this is followed by impotence, which has been described in 10%-17% of cases following internal iliac artery occlusion. The bellbottom technique can be used for a common iliac artery up to 24 mm in diameter given that the largest diameter of the stent graft is 28 mm. There is a paucity of data and evidence regarding the "snorkel and sandwich" technique, which can be used in a few clinical scenarios. The hybrid intervention is comprised of a surgical operation, and is not purely endovascular. The newest branch stent graft technology enables preservation of the anterograde flow of important side branches. Technical success with the newest technique ranges from 85%-96.3%, and in some small series, technical success is 100%. Buttock claudication was reported in up to 4% of patients treated with a branch stent graft at 5-year follow-up. Mid- and short-term follow-up results showed branch patency of up to 88% during the 5-6-year period. Furthermore, branch graft occlusion is a potential complication, and it has been described to occur in 1.2%-11% of cases. Iliac branch stent graft placement represents a further development in endovascular medicine, and it has a high technical success rate without serious complications.