An Ex Vivo Human Kidney Perfusion Model Confirms Larger Microwave Ablation Dimensions After Transarterial Embolization.

PURPOSE: To utilize a novel ex vivo perfused human renal model and quantify microwave ablation (MWA) size differences in renal tissue when combining MWA with transarterial embolization (TAE). MATERIALS AND METHODS: Human kidneys (n = 5) declined for transplantation were obtained and connected to a fluoroscopic-compatible ex vivo perfusion system. Two ablations-1 standard MWA, 1 TAE-MWA-were performed in each kidney for 2 minutes at 100 Watts using a MWA system (Solero Angiodynamics). MWA alone was performed in the upper pole. In the lower pole, MWA was performed after TAE with M0 LUMI microspheres (Boston Scientific) to achieve angiographic stasis. Ablation zones of coagulative necrosis were sectioned along the long axis and segmented for maximal short axis diameter (SAD) and long axis diameter (LAD) measurements. RESULTS: A total of 10 ablations (5 MWA, 5 TAE-MWA) were performed in five human kidneys. TAE-MWA resulted in significantly increased SAD, LAD, volume, and sphericity compared to standard MWA + SD with mean measurements as follows (5 standard MWA + SD vs 5 TAE-MWA, two-tailed t-test): SAD, 1.8 ± 0.1 cm vs 2.5 ± 0.1 cm (p < 0.001); LAD, 2.9 ± 0.3 cm vs 3.2 ± 0.1 cm (p = 0.039); volume, 5.0 ± 0.5 mL vs 11.0 ± 0.7 mL (p < 0.001); sphericity, 0.4 ± 0.2 vs 0.6 ± 0.1 (p = 0.049). Histology demonstrated no differences in TAE-MWA other than concentrated microspheres. CONCLUSION: This study utilized a novel ex vivo human kidney perfusion model to confirm combined MWA-TAE significantly increases ablation size and spherical shape.

Biliary Leaks: Multidisciplinary Approach to Diagnosis and Treatment.

Bile leaks arise from various causes such as trauma, complications after hepatobiliary surgery, and intrahepatic malignancies or their associated liver-directed treatments. Bile leaks can result in significant morbidity and mortality. Delayed diagnosis is not uncommon due to nonspecific manifestations; therefore, a high clinical suspicion is needed. A multidisciplinary approach for treatment of biliary leaks with prompt referral to tertiary care centers with experienced hepatobiliary surgeons, advanced endoscopists, and interventional radiologists is needed to address these challenging complications. Management of biliary leaks can range from conservative management to open surgical repair. Minimally invasive procedures play a crucial role in biliary leak treatment, and the interventional radiologist can help guide appropriate management on the basis of a clear understanding of the pathophysiology of biliary leaks and a current knowledge of the armamentarium of treatment options. In most cases, a simple diversion of bile to decompress the biliary system may prove effective. However, persistent and high-output biliary leaks require delineation of the source with tailored treatment options to control the leak. This may be done by additional diversions, occluding the source, reestablishing connections, or using a combination of therapies to bridge to more definitive surgical interventions. The authors describe the different treatment options and emphasize the role of interventional radiology. ©RSNA, 2024.

Integrative multi-omics characterization of hepatocellular carcinoma in Hispanic patients.

Background: The incidence and mortality rates of hepatocellular carcinoma (HCC) among Hispanics in the United States are much higher than those of non-Hispanic whites. We conducted comprehensive multi-omics analyses to understand molecular alterations in HCC among Hispanic patients. Methods: Paired tumor and adjacent non-tumor samples were collected from 31 Hispanic HCC in South Texas (STX-Hispanic) for genomic, transcriptomic, proteomic, and metabolomic profiling. Additionally, serum lipids were profiled in 40 Hispanic and non-Hispanic patients with or without clinically diagnosed HCC. Results: Exome sequencing revealed high mutation frequencies of AXIN2 and CTNNB1 in STX Hispanic HCCs, suggesting a predominant activation of the Wnt/ß-catenin pathway. The TERT promoter mutation frequency was also remarkably high in the Hispanic cohort. Cell cycles and liver functions were identified as positively- and negatively-enriched, respectively, with gene set enrichment analysis. Gene sets representing specific liver metabolic pathways were associated with dysregulation of corresponding metabolites. Negative enrichment of liver adipogenesis and lipid metabolism corroborated with a significant reduction in most lipids in the serum samples of HCC patients. Two HCC subtypes from our Hispanic cohort were identified and validated with the TCGA liver cancer cohort. The subtype with better overall survival showed higher activity of immune and angiogenesis signatures, and lower activity of liver function-related gene signatures. It also had higher levels of immune checkpoint and immune exhaustion markers. Conclusions: Our study revealed some specific molecular features of Hispanic HCC and potential biomarkers for therapeutic management of HCC and provides a unique resource for studying Hispanic HCC.

Percutaneous Removal of Migrated Gastrointestinal Stents Using Gastrostomy Access.

This report describes the experience of removing migrated gastrointestinal (GI) stents using a gastrostomy (G) access. Four male patients aged 23-62 years (mean, 42 years) had 6 migrated stents removed using an existing (n = 3) or new (n = 1) G access. Removed stents included 5 covered esophageal stents that migrated into the stomach and 1 distal noncovered duodenal stent that migrated into the proximal duodenum. One patient had 2 stents removed during the same session. All stents were removed successfully without adverse events. Techniques used included the folding technique using a wire in 3 stents and forceps in 2 stents. Eversion technique was used in the duodenal stent. The G or gastrojejunostomy tubes were replaced after stent removal and used for enteral feedings. In conclusion, removing migrated GI stents using an existing or new G access was technically successful and safe.

Evaluation of the Catheter Clamp over Hydrophilic Guide Wire Central Venous Catheter Exchange Technique for Air Embolism Prophylaxis in an In Vitro Model.

PURPOSE: To develop a reproducible in vitro model simulating central venous catheter (CVC) exchange with high potential for air embolization and test the hypothesis that a closed catheter clamp over hydrophilic guide wire exchange technique will significantly reduce the volume of air introduced during CVC exchange. MATERIALS AND METHODS: The model consisted of a 16-F valved sheath, 240-mL container, and pressure transducer submerged in water in a 1,200-mL suction canister system. Continuous wall suction was applied to the canister to maintain negative pressure at -7 mm Hg or -11 mm Hg. Each trial consisted of 0.035-inch hydrophilic guide wire introduction, over-the-wire catheter exchange, and wire removal following clinical protocol. A total of 256 trials were performed, 128 trials at each pressure with the catheter clamp open (n = 64) or closed (n = 64) around the hydrophilic guide wire. RESULTS: There was a statistically significant lower volume of air introduced with closed clamp over-the-wire exchanges than with open clamp exchanges at both pressures (2-tailed t-test, P < .001). At -7 mm Hg, a mean of 48.0 mL (SD ± 9.3) of air was introduced with open clamp and 20.6 mL (SD ± 4.7) of air was introduced with closed clamp. At -11 mm Hg, 97.8 mL (SD ± 11.9) of air was introduced with open clamp and 37.8 mL (SD ± 6.3) of air was introduced with closed clamp. CONCLUSIONS: This study demonstrated the use of a reproducible in vitro model mimicking conditions causing air embolism during CVC exchange. Results showed that CVC exchange using closed catheter clamp over hydrophilic guide wire exchange technique significantly reduced the volume of air introduced per exchange.

Self-expanding Metal Stents in Malignant Obstruction of the Esophagus: A 25-Year Multicentric Study

Background: Self-expanding metal prostheses improve dysphagia in patients with incurable esophageal cancer (EC). New stents have been introduced, and chemoradiotherapy has been implemented for EC, changing patients' risk profiles. It is unknown whether this has affected palliation with stents. Patients and methods: Retrospective study in three centers in Medellín-Colombia; patients undergoing placement of palliative esophageal prostheses for malignant dysphagia (1997-2022). Major and minor complications after implantation, the influence of oncological therapies, and survival were evaluated for 1997-2009 (n = 289) and 2010-2022 (n = 318). Results: 607 patients underwent esophageal prostheses; 296 (48.8%) became complicated. It was higher in the second period (52.5% vs. 48.1%), as were major complications (20.8% vs. 14.2%, p = 0.033), with no differences in minor complications (33.9% vs 31.8%, p = 0.765). Also, 190 (31.3%) patients presented with recurrent dysphagia, stable in both periods. Migration increased over time (from 13.1% to 18.2%, p = 0.09). The most common minor adverse event was pain, increasing over time (from 24.9% to 33.95%, p < 0.01), and associated factors were chemoradiotherapy, absence of fistula, and squamous cell carcinoma. Acid reflux decreased in the second group (p = 0.038). Twelve percent of patients required another intervention for feeding. Survival was not impacted by time and use of stents. Conclusions: Stents are an alternative in non-surgical malignant dysphagia, although recurrent dysphagia has not decreased over time. Minor stent-related complications are increasing in association with the implementation of chemoradiotherapy.

Antecedentes: Las prótesis metálicas autoexpandibles mejoran la disfagia en pacientes con cáncer esofágico (CE) incurable. En las últimas décadas se han introducido nuevos tipos de stents y se ha implementado la quimiorradioterapia para el CE, generando cambios en los perfiles de riesgo de los pacientes. Se desconoce si estos cambios han afectado la paliación con stents. Pacientes y métodos: Estudio retrospectivo en tres centros de Medellín-Colombia; pacientes sometidos a colocación de prótesis esofágicas paliativas para disfagia maligna (1997-2022). Se evaluaron en dos períodos: 1997-2009 (n = 289) y 2010-2022 (n = 318), complicaciones mayores y menores después del implante, la influencia de las terapias oncológicas y la sobrevida. Resultados: Se evaluaron 607 pacientes sometidos a prótesis esofágicas. 296 (48,8%) se complicaron, y fue mayor en el segundo periodo (52,5% frente a 48,1%), al igual que las complicaciones mayores (20,8% frente a 14,2%, p = 0,033), sin diferencias en complicaciones menores (33,9% frente a 31,8%, p = 0,765). 190 (31,3%) pacientes presentaron disfagia recurrente, estable en ambos períodos. La migración aumentó con el tiempo (de 13,1% a 18,2%, p = 0,09). El evento adverso menor más frecuente fue dolor, que aumentó con el tiempo (de 24,9% a 33,95%, p < 0,01), y los factores asociados fueron quimiorradioterapia, ausencia de fístula y carcinoma de células escamosas. El reflujo ácido disminuyó en el segundo grupo (p = 0,038). El 12% de pacientes requirieron otra intervención para alimentarse. No se impactó la sobrevida con el tiempo y uso de stents. Conclusiones: Los stents son una alternativa en la disfagia maligna no quirúrgica, aunque la disfagia recurrente no ha disminuido con el tiempo. Las complicaciones menores relacionadas con el stent van en aumento, asociadas a la implementación de la quimiorradioterapia.

Abscess drain migration into the colon following laparoscopic cholecystectomy.

Percutaneous abscess drainage is a procedure commonly performed by interventional radiologists to provide source control on infections using CT or ultrasound guidance. The interventionalist has many different sizes and shapes of catheters to treat abscesses of varying sizes and locations, but the general approach to each abscess is similar: provide a percutaneous route for purulence, bacteria, necrotic tissue, and other debris to escape the body. While generally considered a low-risk procedure, adverse events can occur due to operator error or other means. We present a unique case of an abscess drain placed into a right upper quadrant abscess that formed following laparoscopic cholecystectomy that perforated and entered the colon. Astute physicians, both in the emergency department and the radiology reading room, were able to rapidly rule out more common post-operative complications and make the correct diagnosis, likely preventing dangerous sequelae from developing in this patient.

Multifocal hepatocellular carcinoma: a narrative review assessing treatment options from the interventional radiologist's perspective.

BACKGROUND AND OBJECTIVE: It is estimated that 35-40% of hepatocellular carcinoma (HCC) patients present with multiple nodules at the time of diagnosis. Treating multifocal disease is difficult given patient population heterogeneity. Multiple interventional radiological (IR) options, including ablation, transarterial chemoembolization (TACE), and transarterial radioembolization (TARE), are available, each with its own merits and limitations. Our aim is to explore the current state of the literature to identify where each of these options is best applied to multifocal HCC management. METHODS: A narrative literature review of 107 papers was performed in PubMed. Articles from 2010 and newer were used for clinical data and for classification/scoring system details. The majority of the keywords for searches include the treatment modality name alongside terms such as "HCC", "multifocal", or "multinodular". KEY CONTENT AND FINDINGS: Ablation is a curative option for Barcelona Clinic Liver Cancer (BCLC) A disease and is appropriate when liver transplantation (LT) is impractical. It is ideal in disease with ≤3 nodules (each <3 cm) preferably confined to one segment. TACE [conventional TACE (cTACE), drug-eluting bead TACE (DEB-TACE), balloon-occluded TACE (B-TACE), and less so hepatic arterial infusion chemotherapy (HAIC)] is the major workhorse for multifocal BCLC B disease, in pre-transplant downstaging, and in advanced disease palliation. The Kinki BCLC B subclassification can guide TACE subtype selection. TACE response can be assessed over 2-3 sessions per modified Response Evaluation Criteria in Solid Tumors (mRECIST) and patient session tolerance. TARE is an option for BCLC C disease, with BCLC A/B applications limited by radiation induced liver disease (RILD). Pseudo-ablative techniques like sub-selective TARE (sTARE) are promising but are unproven and less useful in multinodular disease. Finally, combination therapies [TACE + ablation, liver resection (LR) + ablation/TACE] are an exciting option but warrant further study. CONCLUSIONS: Multifocal HCC remains challenging to manage. While BCLC is a useful starting point, the patient's tumor imaging characteristics and clinical circumstances must be considered when selecting the appropriate treatment modality.

Experimental Analysis of Passenger Comfort with Variable Preloaded Rear Springs on a Low-Cylinder Motorcycle.

The present study contains an experimental analysis of the vibratory response in a low-cylinder engine motorcycle at varying suspension preloads. Three different speed bumps of varying heights were used to subject the motorcycle to different vibrations. The analysis was carried out in three domains: time, frequency, and time-frequency. A triaxial accelerometer was used to measure the vibrations at the seat of the vehicle. The results indicated that the suspension system became more differentiated as the height of the bumps increased. However, for lower bumps, the action of the three spring preloads studied was quite similar. Quantitatively, only the higher bump showed a significant difference between the set preloads. The spectral distribution revealed that the frequency of interest was below 20 Hz for all the studied cases, which is in the same range of human body natural frequencies. The findings of this research can be utilized to enhance the design of low-cost motorcycles, thereby improving the safety and comfort of their drivers and passengers. This study constitutes a significant step towards developing an affordable system capable of gathering sufficient data to support the creation of evidence-based public health policies and propose new transport industry standards based on field measurements.

What are the Andean Colombian anurans? Empirical regionalization proposals vs. observed patterns of compositional dissimilarity.

Background: Defining Andean anurans through their altitudinal limits has been a common practice in species lists, studies of responses to climate change among others, especially in the northern Andes. At least three proposals to differentiate Andean anurans from lowland anurans through elevation and at least one to differentiate Andean anurans from high mountain anurans have been formulated. However, the most frequently used altitudinal limits are not based on theoretical or numerical support, but on observations or practical definitions. Additionally, these proposals have been applied equally to different portions of the Andes, ignoring the fact that even between slopes of the same mountain, environmental conditions (and therefore the distribution of species) may differ. The objective of this work was to evaluate the concordance between the altitudinal distribution of anurans in the Colombian Andes and four different altitudinal delimitation proposals. Methods: We constructed our study area in a manner that allowed us to include species from the Andean region (as traditionally defined) and adjacent lowlands, because if the boundaries criteria were applied they would separate the species of the latter by themselves. We divided the study area into eight entities according to the watershed and the course of the most important rivers. We conducted a bibliographic search for all anurans in the cordilleras and inter-Andean valleys of Colombia and complemented the search with information on anurans for the region available in the GBIF. After curing the species distribution points, we generated elevation bands of 200 m amplitude for both the study area and for each Andean entity. Subsequently, we performed a cluster analysis to evaluate the grouping of the elevation bands according to their species composition. Results: In none of the cases (neither for the entire study area nor for any of the entities) we found a correspondence of any of the traditionally used boundaries and the altitudinal distribution of Anurans in the Andean region of Colombia. Instead, on average, the altitudinal delimitation proposals arbitrarily spanned the altitudinal distribution of about one third of the species distributed in the study area. Conclusions: We suggest that, although, based on our results, some Andean entities can be divided according to the altitudinal composition of the species that occur in them, we did not find any results that support the idea of a generalizable altitudinal limit for the Colombian Andes. Thus, to avoid biases in studies that may later be used by decision makers, the selection of anuran species in studies in the Colombian Andes should be based on biogeographic, phylogenetic or natural history criteria and not on altitudinal limits as they have been used.

Transjugular Intrahepatic Portosystemic Shunt Reductions.

Transjugular intrahepatic portosystemic shunts (TIPS) are effective in reducing the portosystemic gradient and relieving complications of portal hypertension. Despite optimal patient selection, TIPS placement can be limited due to worsening hepatic encephalopathy and liver failure. In these cases, TIPS reduction may be necessary. A brief history of TIPS reduction and techniques for reduction are reviewed.

A Comprehensive Review of Transjugular Intrahepatic Portosystemic Shunt-Related Complications.

Transjugular intrahepatic portosystemic shunt (TIPS) is one of the most technically complex procedures in interventional radiology, the need to connect two veins with variable anatomy, located in two different planes in hard and many times small cirrhotic livers using a needle, can be quite challenging. Despite more than 30 years of performing TIPS, the complex hemodynamics of the portal system are not fully understood, and sometimes unpredictable alterations of the portal flow can lead to serious unexpected complications. The best strategies to prevent TIPS complications are optimal patient selection, meticulous technique, operator experience, and immediate correction of identified adverse events. The purpose of this article is to review the technical complications with TIPS, the unique complications related to the use of stent grafts, and the late complications after the procedure, with emphasis on ways to prevent and treat them.

The rat eustachian tube: Anatomical, histological, and radiological features.

Purpose: This study investigated the anatomical and histological characteristics of the rat Eustachian tube (E-tube) and the feasibility of Eustachian tubography in a rat model. Materials and methods: Fifteen male Wistar rats were used in this study, and the bilateral E-tubes of each rat were examined. Ten E-tubes were used for anatomical studies, another ten for histological analysis, and the other ten for Eustachian tubography. Five rats were euthanized and decapitated, and ten E-tubes were dissected to describe the anatomy of the E-tube. Ten E-tube specimens obtained from five other rats were sectioned to investigate E-tube histology. Eustachian tubography was performed on the bilateral E-tubes of the other five rats using the trans-tympanic approach. Results: The rat E-tubes consisted of bony and membranous parts. Cartilage and bone tissue covered only the bony part. The E-tubes' mean diameter and overall length were 2.97 â€‹mm and 4.96 â€‹mm, respectively. The tympanic orifices' mean diameter was 1.21 â€‹mm. The epithelium of E-tubes was mainly composed of pseudostratified ciliated and goblet cells. Eustachian tubography was successfully performed on both sides of the E-tube for each rat. The technical success rate was 100%, the average running time was 4.9 â€‹min, and no procedure-related complications occurred. On tubography images, the E-tube, tympanic cavity, and nasopharynx could be identified because of the visualization of bony landmarks. Conclusion: In this study, we described the anatomical and histological features of rat E-tubes. With the aid of these findings, E-tube angiography was successfully performed using a transtympanic approach. These results will facilitate further investigation of E-tube dysfunction.

Creation of an Ex Vivo Renal Perfusion Model to Investigate Microwave Ablation.

This study hypothesized that an ex vivo renal perfusion model can create smaller microwave ablation (MWA) measurements during perfused states compared with nonperfused states across multiple device settings. Nine bovine kidneys, a fluoroscopic compatible perfusion model, and a commercially-available clinical MWA system were used to perform 72 ablations (36 perfused and 36 nonperfused) at 9 different device settings. Comparing perfused and nonperfused ablations at each device setting, significant differences in volume existed for 6 of 9 settings (P < .05). Collapsed across time settings, the ablation volumes by power were the following (perfused and nonperfused, P value): 60 W, 2.3 cm3 ± 1.0 and 7.2 cm3 ± 2.7, P < .001; 100 W, 5.4 cm3 ± 2.1 and 11.5 cm3 ± 5.6, P < .01; and 140 W, 11.2 cm3 ± 3.7 and 18.7 cm3 ± 6.3, P < .01. Applied power correlated with ablation volume: perfused, 0.021 cm3/W and R = 0.462, P = .004, and nonperfused, 0.029 cm3/W and R = 0.565, P < .001. These results support that an ex vivo perfused organ system can evaluate MWA systems and demonstrate heat sink perfusion effects of decreased ablation size.

Direct transmesenteric venous interventions in the acute post liver transplant setting.

INTRODUCTION: Portal venous thrombosis and stenosis are uncommon but serious causes of liver transplant graft failure. While surgical thrombectomy can be utilized for the treatment of portal steno-occlusive disease, venous interventions with IR have been performed with encouraging results. CASE DESCRIPTION: 69-year-old female with non-alcoholic steatohepatitis cirrhosis who received a liver transplant complicated by portal vein thrombus. Efforts between transplant surgery and IR allowed for successful thrombus removal via direct SMV access. RESULTS: The advantages of direct SMV access with the surgery team include direct approach to accessing thrombus, sparing of liver parenchyma, and significant hemostatic control.

Comparative outcomes of Inferior Vena Cava filters placed at bedside using digital radiography versus conventional fluoroscopy.

PURPOSE: To retrospectively assess the outcomes of Inferior Vena Cava (IVC) filters placed in critically ill patients in the ICU at bedside using digital radiograph (DR) guidance with previous cross-sectional imaging for planning, compared to IVC filters placed by conventional fluoroscopy (CF). METHOD AND MATERIALS: The cohort consisted of 129 IVC filter placements; 48 placed at bedside and 81 placed conventionally from July 2015 to September 2016. Patient demographics, indication, radiation exposures, access site, procedural duration, dwell time, and complications were identified by the EMR. IVC Filter positioning with measurements of tip to renal vein distance and lateral filter tilt were performed when cavograms or post placement CTs were available for review. Statistical analysis was performed using Stata IC 11.2. RESULTS: Technical success of the procedure was 100% in both groups. Procedural duration was longer at the bedside lasting 14.5 +/- 10.2 versus 6.7 +/- 6.0 â€‹min (p<0.0001). The bedside DR group had a median radiation exposure of 25 â€‹mGy (15-35) and the CF group had mean radiation exposure of 256.94 â€‹mGy +/- 158.6. There was no significant difference in distance of IVC tip to renal vein (p=0.31), mispositioning (p=0.59), degree of filter tilt (p=0.33), or rate of complications (p=0.65) between the two groups. CONCLUSION: IVCF placement at the bedside using DR is comparable to CF with no statistical difference in outcomes based on IVCF positioning, degree of lateral tilt or removal issues. It decreased radiation dose, but with overall increased procedural time.