Interventional Management of Portal Vein Stenosis after Liver Transplant: Single Center Experience.

OBJECTIVES: Portal vein stenosis is a relatively rare complication after liver transplant but has severe consequences. We evaluated the efficacy and longterm results of the endovascular treatment methods for portal vein stenosis. MATERIALS AND METHODS: From October 2011 to October 2022, we treated 22 patients (5 female, 17 male) with portal vein stenosis using endovascular methods. Doppler ultrasonography was used for initial diagnosis, with consideration of flow rate increase over stenosis, absence of flow, or reduced anastomotic segment size (>50%). Angiography served as the gold standard, with a pressure gradient above 5 mm Hg indicating the need for treatment. Technical success criteria were defined as <50% stenosis remaining and/or a pressure gradient <5mm Hg. The transhepatic approach was used for all patients. Balloon angioplasty was initially performed, and stents were reserved for patients in the early postoperative period or those unresponsive to balloon angioplasty. RESULTS: The technical success rate was 100%. Mean age was 27.1 years (SD 22.4; range, 4 months to 63 years). Mean time from transplant to intervention was 317 days (range, 0-3135 days). Angioplasty was successful for 7 patients (13.8%). Of 15 patients who underwent stent placement, 9 (40.9%) were in the early postoperative period; in the other 6 patients (27%), results of angioplasty were not satisfactory, and stents were placed. Within 3 months of transplant, 3 patients died because of other complications. Among patients with stents, 2 required reintervention, resulting in reestablishment of good portal venous flow. During the mean follow-up of 24 months (range, 15 days to 9 years), 19 patients (86%) had portal flows within reference limits. CONCLUSIONS: The endovascular approach is a safe and effective treatment option for management of portal vein stenosis in both adult and pediatric liver transplant recipients in the early or late period.

Interventional Treatment Methods for Ureteral Complications After Kidney Transplant: A Single-Center Experience.

OBJECYIVES: Ureteral complications are one of the most common complications after kidney transplant. Although these complications have been treated surgically in the past, almost all can be successfully treated with interventional methods today. In this study, we assessed the interventional treatment of ureteral complications after kidney transplants performed in our center and the long-term results of these treatments. MATERIALS AND METHODS: We performed a retrospective analysis of 2223 kidney transplant recipients seen between January 1, 2000, and May 1, 2020. Among these, 70 kidney transplant recipients who experienced ureteral leakage or ureteral obstruction in the early or late posttransplant period were included in the study. Complications within the first 2 months posttransplant were classified as early complications, whereas those occurring after 2 months were considered late complications. We treated all patients with interventional methods. RESULTS: In review of patients, 44 patients were diagnosed with ureteral obstruction (22 patients were early obstruction, 22 were late obstruction) and 26 patients with ureteral anastomosis leakage. All patients with early and late ureteral obstruction were successfully treated with percutaneous methods. In the group of patients with ureteral leakage, all patients except 2 patients were treated with interventional methods. For 2 patients with ureteral leakage, surgical treatment was necessary because of persistent leakage despite percutaneous treatment methods. CONCLUSIONS: Ureteral complications after kidney transplant can be successfully treated with interventional methods in experienced centers without the need for surgery.

Transarterial Chemoembolization Combined with Simultaneous Thermal Ablation for Solitary Hepatocellular Carcinomas in Regions with a High Risk of Recurrence.

OBJECTIVES: We evaluated the safety and efficacy of transarterial chemoembolization combined with percutaneous thermal ablation (radiofrequency or microwave ablation) in the treatment of solitary hepatocellular carcinoma tumors ranging from 2 to 4.5 cm at subdiaphragmatic, subcapsular, or perivascular locations. MATERIALS AND METHODS: Fifteen patients (12 men, mean [range] age of 66.6 ± 10.88 [34-75] y) who received transarterial chemoembolization combined with simultaneous percutaneous radiofrequency ablation (n = 5) or microwave ablation (n = 10) for hepatocellular carcinoma in regions with high risk of recurrence (subdiaphragmatic, subcapsular, or perivascular) between 2012 and 2018 were evaluated. We retrospectively investigated tumor diameter and localization, success rate, safety, local efficacy (imaging at month 1 after treatment), local tumor response (3 months posttreatment), local tumor progression, intrahepatic distant recurrence, overall survival and complications. RESULTS: Tumor diameter ranged from 20 to 45 mm (mean 31.7 ± 7.37 mm). Hepatocellular carcinoma diameter was 2 to 3 cm in 7 patients and 3.1 to 4.5 cm in 8 patients. The technical success rate was 100%, with no life-threatening complications. At enhanced imaging at 1-month follow-up, the complete necrosis rate was 100%; at 3 months, 100% of patients had a complete response. During a mean follow-up of 26 ± 13.6 months, 7 patients (46.7%) had tumor progression. Three patients (20%) had local tumor response, and 4 patients (26.7 %) experienced distant recurrences in the untreated liver. The mean local tumor progression and mean intrahepatic distance recurrence times were 11 months and 29.5 months, respectively. Overall survival rates were 100% at 1 year, 73% at 3 years, and 47% at 5 years. CONCLUSIONS: Transarterial chemoembolization combined with simultaneous percutaneous thermal ablation is safe, feasible, and effective in enhancing the local control rate for solitary hepatocellular carcinoma ranging from 2 to 4.5 cm in regions with high risk of recurrence.

Percutaneous revision of dysfunctional shunts in patients who underwent intrahepatic portosystemic shunt procedure via percutaneous or conventional method: 11-years single center experience.

BACKGROUND AND AIM: Our primary objective is to report the results of the ultrasound (US)-guided revision technique of transhepatic shunt in patients in whom intrahepatic portosystemic shunt was created by the percutaneous or conventional route. Our secondary objective is to investigate whether there is an association between the indication for a portosystemic shunt and the need for post-shunt revision. METHODS: Data from 117 consecutive patients who had a transjugular intrahepatic portosystemic shunt placed percutaneously or conventionally were extracted from hospital electronic medical records and examined those who underwent revision within 11 years and those who did not. US-guided transhepatic shunt revision technique was evaluated in terms of technical success, complications, and patency. In addition, the relationship between etiology and the need for revision was also examined using the chi-square test in three groups. RESULTS: Forty six point two percent of patients who underwent transjugular intrahepatic portosystemic shunt required one or more revisions within 11 years. While patency of the shunt could be established via the transjugular route in 83.3% of revision patients, it was necessary to use the transhepatic route in 16.7%. The technical success rate for the US-guided transhepatic shunt revision method was 100%, and the pressure gradient between the portal and hepatic venous systems decreased below 10 mmHg in all patients at the end of the procedure. CONCLUSION: US-guided transhepatic shunt revision is a safe and effective method where transjugular revision cannot be performed. In addition, the revision rate is significantly higher in patients who have undergone transjugular intrahepatic portosystemic shunt due to Budd-Chiari syndrome compared with other groups.

Performance of quantitative CT texture analysis in differentiation of gastric tumors.

PURPOSE: To examine the computed tomography (CT) images of patients with a diagnosis of gastric tumor by texture analysis and to investigate its place in differential diagnosis. MATERIALS AND METHODS: Contrast enhanced venous phase CT images of 163 patients with pathological diagnosis of gastric adenocarcinoma (n = 125), gastric lymphoma (n = 12) and gastrointestinal stromal tumors (n = 26) were retrospectively analyzed. Pixel size adjustment, gray-level discretization and gray-level normalization procedures were applied as pre-processing steps. Region of interest (ROI) was determined from the axial slice that represented the largest lesion area and a total of 40 texture features were calculated for each patient. Texture features were compared between the tumor subtypes and between adenocarcinoma grades. Statistically significant texture features were combined into a single parameter by logistic regression analysis. The sensitivity and specificity of these features and the combined parameter were measured to differentiate tumor subtypes by receiver-operating characteristic curve (ROC) analysis. RESULTS: Classifications between adenocarcinoma versus lymphoma, adenocarcinoma vs. gastrointestinal stromal tumor (GIST) and well-differentiated adenocarcinoma versus poorly differentiated adenocarcinoma using texture features yielded successful results with high sensitivity (98, 91, 96%, respectively) and specificity (75, 77, 80%, respectively). CONCLUSIONS: CT texture analysis is a non-invasive promising method for classifying gastric tumors and predicting gastric adenocarcinoma differentiation.