Safety and Diagnostic Efficacy of Image-Guided Biopsy of Small Renal Masses.

INTRODUCTION: Image-guided renal mass biopsy is gaining increased diagnostic acceptance, but there are limited data concerning the safety and diagnostic yield of biopsy for small renal masses (≤4 cm). This study evaluated the safety, diagnostic yield, and management after image-guided percutaneous biopsy for small renal masses. METHODS: A retrospective IRB-approved study was conducted on patients who underwent renal mass biopsy for histopathologic diagnosis at a single center from 2015 to 2021. Patients with a prior history of malignancy or a renal mass >4 cm were excluded. Descriptive statistics were used to summarize patient demographics, tumor size, the imaging modality used for biopsy, procedure details, complications, pathological diagnosis, and post-biopsy management. A biopsy was considered successful when the specimen was sufficient for diagnosis without need for a repeat biopsy. Complications were graded according to the SIR classification of adverse events. A chi-squared test (significance level set at p ≤ 0.05) was used to compare the success rate of biopsies in different lesion size groups. RESULTS: A total of 167 patients met the inclusion criteria. The median age was 65 years (range: 26-87) and 51% were male. The median renal mass size was 2.6 cm (range: one-four). Ultrasound was solely employed in 60% of procedures, CT in 33%, a combination of US/CT in 6%, and MRI in one case. With on-site cytopathology, the median number of specimens obtained per procedure was four (range: one-nine). The overall complication rate was 5%. Grade A complications were seen in 4% (n = 7), consisting of perinephric hematoma (n = 6) and retroperitoneal hematoma (n = 1). There was one grade B complication (0.5%; pain) and one grade D complication (0.5%; pyelonephritis). There was no patient mortality within 30 days post-biopsy. Biopsy was successful in 88% of cases. A sub-group analysis showed a success rate of 85% in tumors <3 cm and 93% in tumors ≥3 cm (p = 0.01). Pathological diagnoses included renal cell carcinoma (65%), oncocytoma (18%), clear cell papillary renal cell tumors (9%), angiomyolipoma (4%), xanthogranulomatous pyelonephritis (1%), lymphoma (1%), high-grade papillary urothelial carcinoma (1%), and metanephric adenoma (1%), revealing benign diagnosis in 30% of cases. The most common treatment was surgery (40%), followed by percutaneous cryoablation (22%). In total, 37% of patients were managed conservatively, and one patient received chemotherapy. CONCLUSION: This study demonstrates the safety and diagnostic efficacy of image-guided biopsy of small renal masses. The diagnostic yield was significantly higher for masses 3-4 cm in size compared to those <3 cm. The biopsy results showed a high percentage of benign diagnoses and informed treatment decisions in most patients.

Treatment of Unicameral Bone Cysts Utilizing the Sclerograft™ Technique.

PURPOSE: To evaluate the Sclerograft™ procedure, which is an image-guided, minimally invasive approach of chemical sclerotherapy followed by bone grafting of unicameral bone cysts (UBC). MATERIALS AND METHODS: A retrospective evaluation from August 2018 through August 2023 was performed at a single institution on patients that underwent the Sclerograft™ procedure for UBCs. Radiographic healing was evaluated utilizing the Modified Neer Classification. Two different regenerative grafts, CaSO4-CaPO4 and HA-CaSO4 were utilized. A total of 50 patients were evaluated with 41 patients grafted with CaSO4-CaPO4 and 9 patients grafted with HA-CaSO4. RESULTS: The average age of the patient was 12.1 years with an average radiographic follow-up of 14.5 months. Average cyst size was 5.5 cm in the largest dimension and average cyst volume was 20.2 cc. 42 out of 50 (84%) showed healed cysts (Modified Neer Class 1) on the most recent radiograph or MRI. Recurrences occurred on average at 7.2 months. Activity restrictions were lifted at 3-4.5 months post-procedure. Cyst stratification by size did not show a difference in recurrence rates (p = 0.707). There was no significant difference in recurrence rate between lesions abutting the physis compared to those that were not abutting the physis (p = 0.643). There were no major complications. CONCLUSIONS: The Sclerograft™ procedure is an image-guided approach to treating unicameral bone cysts, utilizing chemical sclerosis and regenerative bone grafting. The radiographic healing of cysts compares favorably to open curettage and grafting as determined utilizing previously published trials.

Hepatic Encephalopathy following Transjugular Intrahepatic Portosystemic Shunt Placement.

Hepatic encephalopathy (HE) is a complex condition that arises as a complication of chronic liver disease and portosystemic shunting. Its pathophysiology involves several factors, including impaired ammonia metabolism, portosystemic shunting, sarcopenia, and systemic inflammation. The symptoms of HE can vary significantly, with manifestations ranging from subclinical signs to a comatose state. The West Haven classification system is most commonly used to grade the severity of HE. There is a broad differential for the presenting symptomatology of HE and other causes of altered mental status must be excluded during the workup. HE is a well-known complication of transjugular intrahepatic portosystemic shunt (TIPS) placement. Even though newer stent designs help reduce the risk of HE with smaller diameter shunts, it is essential that patients are counseled regarding this potential risk prior to the procedure. Once a diagnosis of HE has been confirmed, the mainstay of therapy is lactulose and rifaximin. In cases where a patient has received a TIPS placement and continues to experience refractory HE despite medical therapy, it may be necessary to consider shunt reduction or closure.

Portal Vein Recanalization-Transjugular Intrahepatic Portosystemic Shunt (PVR-TIPS) Facilitates Liver Transplantation in Cirrhotic Patients with Occlusive Portal Vein Thrombosis.

Portal vein thrombosis (PVT) is a heterogeneous condition with multiple possible etiologies and to varying degrees has historically limited candidacy for liver transplant (LT) in the cirrhotic patient population due to resultant difficulties in constructing a robust portal vein anastomosis. While intraoperative approaches to managing PVT are well-described, methods which approximate normal portal physiology are not always feasible depending on the extent of PVT, and other nonphysiologic techniques are linked with substantial morbidity and poor long-term outcomes. Portal vein recanalization-transjugular intrahepatic portosystemic shunt (PVR-TIPS) creation is an efficacious method of restoring physiologic portal flow in cirrhotic patients prior to LT allowing for end-to-end PV anastomosis, and is the product of decades-long institutional expertise in TIPS/LT and the support of a multidisciplinary liver tumor board. To follow is a review of the pertinent pathophysiology of PVT in cirrhosis, the rationale leading to the development and subsequent evolution of the PVR-TIPS procedure, technical lessons learned, and a summary of outcomes to date.

Change in Platelet Count after Transjugular Intrahepatic Portosystemic Shunt Creation: An Advancing Liver Therapeutic Approaches (ALTA) Group Study.

PURPOSE: To evaluate recovery of platelet count after transjugular intrahepatic portosystemic shunt (TIPS) creation and patient factors predicting platelet recovery after TIPS creation. MATERIALS AND METHODS: Adults with cirrhosis who underwent TIPS creation at 9 U.S. hospitals from 2010 to 2015 were included in this retrospective analysis. Change in platelets from before TIPS to 4 months after TIPS creation was characterized. Logistic regression was used to assess factors associated with top quartile percentage platelet increase after TIPS. Subgroup analyses were performed among patients with a pre-TIPS platelet count of ≤50 ×109/L. RESULTS: A total of 601 patients were included. The median absolute change in platelets was 1 × 109/L (-26 × 109/L to 25 × 109/L). Patients with top quartile percent platelet increase experienced ≥32% platelet increase. In multivariable analysis, pre-TIPS platelet counts (odds ratio [OR], 0.97 per 109/L; 95% CI, 0.97-0.98), age (OR, 1.24 per 5 years; 95% CI, 1.10-1.39), and pre-TIPS model for end-stage liver disease (MELD) scores (OR, 1.06 per point; 95% CI, 1.02-1.09) were associated with top quartile (≥32%) platelet increase. Ninety-four (16%) patients had a platelet count of ≤50 × 109/L before TIPS. The median absolute platelet change was 14 × 109/L (2 × 109/L to 34 × 109/L). Fifty-four percent of patients in this subgroup were in the top quartile for platelet increase. In multivariable logistic regression, age (OR, 1.50 per 5 years; 95% CI, 1.11-2.02) was the only factor associated with top quartile platelet increase in this subgroup. CONCLUSIONS: TIPS creation did not result in significant platelet increase, except among patients with a platelet count of ≤50 × 109/L before TIPS. Lower pre-TIPS platelet counts, older age, and higher pre-TIPS MELD scores were associated with top quartile (≥32%) platelet increase in the entire cohort, whereas only older age was associated with this outcome in the patient subset with a pre-TIPS platelet count of ≤50 × 109/L.

Radioembolization for Intermediate-Stage Hepatocellular Carcinoma Maintains Liver Function and Permits Systemic Therapy at Progression.

PURPOSE: To assess the liver function trends in patients with intermediate-stage (Barcelona Clinic Liver Cancer [BCLC] Stage B) hepatocellular carcinoma (HCC) who underwent yttrium-90 transarterial radioembolization (TARE) in response to a growing concern that liver-directed therapies negatively affect liver function and prevent patients with HCC from systemic therapy candidacy. MATERIALS AND METHODS: An HCC/TARE database (2004-2017) was retrospectively reviewed. Patients with BCLC Stage B/Child-Pugh (CP)-A HCC with laboratory test and imaging data at baseline and for at least 1 month after TARE were included. Follow-ups were at 3-month intervals. CP stage was assessed at each time point. End points included time to persistent CP-B status, time to CP-C status, and median overall survival (OS). Time-to-end point analyses were performed using the Kaplan-Meier method. RESULTS: Seventy-four patients (80% men, with a mean age of 63 years) with mostly (62%) bilobar disease underwent 186 TARE treatments (median, 2; range, 1-8). The median time to second TARE was 2.3 months (range, 1.7-6.4 months), and the median times to third and fourth TAREs were 11.7 months (range, 7.5-15 months) and 17.3 months (range, 11.5-23.1 months), respectively. Forty-three (58%) patients developed persistent CP-B HCC at a median time of 15.4 months (95% CI, 9.2-25.3 months); 17 (23%) patients developed CP-C HCC at a median time of 87.2 months (95% CI, 39.8-136.1 months). The median OS censored to transplantation was 30.4 months (95% CI, 22.7-37.4 months). On univariate and multivariate analyses, baseline albumin was a significant prognosticator of OS, whereas baseline albumin and bilirubin were significant prognosticators of time to persistent CP-B HCC and time to CP-C HCC. CONCLUSIONS: In patients with CP-A HCC who underwent TARE for BCLC Stage B HCC, the median time to persistent CP-B HCC was 15.4 months. These findings indicate that patients would be candidates for systemic therapy at progression if indicated.

The impact of right atrial pressure on outcomes in patients undergoing TIPS, an ALTA group study.

BACKGROUND AND AIMS: Single-center studies in patients undergoing TIPS suggest that elevated right atrial pressure (RAP) may influence survival. We assessed the impact of pre-TIPS RAP on outcomes using the Advancing Liver Therapeutic Approaches (ALTA) database. APPROACH AND RESULTS: Total 883 patients in ALTA multicenter TIPS database from 2010 to 2015 from 9 centers with measured pre-TIPS RAP were included. Primary outcome was mortality. Secondary outcomes were 48-hour post-TIPS complications, post-TIPS portal hypertension complications, and post-TIPS inpatient admission for heart failure. Adjusted Cox Proportional hazards and competing risk model with liver transplant as a competing risk were used to assess RAP association with mortality. Restricted cubic splines were used to model nonlinear relationship. Logistic regression was used to assess RAP association with secondary outcomes.Pre-TIPS RAP was independently associated with overall mortality (subdistribution HR: 1.04 per mm Hg, 95% CI, 1.01, 1.08, p =0.009) and composite 48-hour complications. RAP was a predictor of TIPS dysfunction with increased odds of post-90-day paracentesis in outpatient TIPS, hospital admissions for renal dysfunction, and heart failure. Pre-TIPS RAP was positively associated with model for end-stage liver disease, body mass index, Native American and Black race, and lower platelets. CONCLUSIONS: Pre-TIPS RAP is an independent risk factor for overall mortality after TIPS insertion. Higher pre-TIPS RAP increased the odds of early complications and overall portal hypertensive complications as potential mechanisms for the mortality impact.

Percutaneous Cystic Duct Interventions and Drain Internalization for Calculous Cholecystitis in Patients Ineligible for Surgery.

PURPOSE: To evaluate the feasibility, effectiveness, and outcomes of percutaneous cholecystostomy drain internalization in patients with calculous cholecystitis who were not surgical candidates. MATERIALS AND METHODS: Percutaneous cystic duct interventions were attempted in 17 patients (with the intent to place dual cholecystoduodenal stents) who were deemed unfit for surgery and had previously undergone percutaneous cholecystostomies for acute calculous cholecystitis. Baseline demographics, technical success, time from percutaneous cholecystostomy to internalization (dual cholecystoduodenal stent placement), stent patency duration, and adverse event rates were evaluated. RESULTS: Fifteen (88%) of 17 procedures to cross the cystic duct were technically successful. Of these 17 patients, 13 (76%) underwent successful placement of dual cholecystoduodenal stents. Two of these 13 patients (who had successful dual cholecystoduodenal stent placement) needed repeat percutaneous cholecystostomy drains (1 patient had stent migration leading to recurrent cholecystitis, and the other had a perihepatic biloma). The 1-year patency rate was 77% (95% CI, 47%-100%). CONCLUSIONS: Dual cholecystoduodenal stent placement in nonsurgical patients is a technically feasible treatment option with the goal to remove percutaneous cholecystostomy drains.

Promoting Surgical Resection through Future Liver Remnant Hypertrophy.

An inadequate future liver remnant (FLR) can preclude curative-intent surgical resection for patients with primary or secondary hepatic malignancies. For patients with normal baseline liver function and without risk factors, an FLR of 20% is needed to maintain postsurgical hepatic function. However, the FLR requirement is higher for patients who are exposed to systemic chemotherapy (FLR, >30%) or have cirrhosis (FLR, >40%). Interventional radiologic and surgical methods to achieve FLR hypertrophy are evolving, including portal vein ligation, portal vein embolization, radiation lobectomy, hepatic venous deprivation, and associating liver partition and portal vein ligation for staged hepatectomy. Each technique offers particular advantages and disadvantages. Knowledge of these procedures can help clinicians to choose the suitable technique for each patient. The authors review the techniques used to develop FLR hypertrophy, focusing on technical considerations, outcomes, and the advantages and disadvantages of each approach. Online supplemental material is available for this article. ©RSNA, 2022.

How Endoscopic Guidance Augments Nonvascular Image-guided Interventions.

Endoscopy can improve guidance in nonvascular procedures performed by interventional radiologists (IRs). Historically, the major limiting factors preventing the widespread use of endoscopic tools by IRs were the large diameter (>20F) and length of the endoscopes. IRs had to significantly upsize their access into vascular organs such as the kidney and liver to allow endoscope placement. With the advent of newer endoscopes with sizes smaller than 11F (approximately 4 mm in diameter), percutaneous endoscopy has become more feasible than before. IRs routinely place percutaneous drains (eg, abscess drains, biliary drains, percutaneous nephrostomies, and percutaneous cholecystostomies). Once the drain is in position and the acute infection (if present) has resolved, the IR can use the percutaneous access to perform image-guided and endoscopically guided procedures, depending on the clinical situation. Most percutaneous image- and endoscopically guided interventions performed by IRs involve procedures for biliary and gallbladder pathologic conditions. Image-guided procedures with additional endoscopic guidance can also be used to manage urinary, gastrointestinal, and gynecologic pathologic conditions. The authors review the current applications and techniques of percutaneous endoscopy in interventional radiology. In unique situations, IRs can also perform endoscopy through natural orifices (eg, the urethra) or surgically created orifices (eg, urostomies). The authors also discuss the adjunctive techniques that are enhanced or made possible because of endoscopy in interventional radiology, including but not limited to endoscopic forceps biopsies, endobiliary ablation, laser stricturotomy, lithotripsy, and stone extraction. An invited commentary by Srinivasa is available online. Online supplemental material is available for this article. ©RSNA, 2022.

Impact of Portal Hypertension on Adverse Events after Splenic Arterial Aneurysm Embolization.

PURPOSE: To evaluate the outcomes of splenic artery aneurysm (SAA) embolization and compare adverse event (AE) rates after embolization in patients with and without portal hypertension (PHTN). MATERIALS AND METHODS: A retrospective review of all patients who underwent embolization of SAAs at 2 institutions was performed (34 patients from institution 1 and 7 patients from institution 2). Baseline demographic characteristics, preprocedural imaging, procedural techniques, and postprocedural outcomes were evaluated. Thirty-day postprocedural severe and life-threatening AEs were evaluated using the Society of Interventional Radiology guidelines. Thirty-day mortality and readmission rates were also evaluated. t test, χ2 test, and/or Fisher exact test were used for the statistical analysis. RESULTS: There was no statistically significant difference between patients with and without PHTN in the location, number, and size of SAA(s). All procedures were technically successful. There were 13 (32%) patients with and 28 (68%) patients without PHTN. The 30-day mortality rate (31% vs 0%; P = .007), readmission rates (61% vs 7%; P < .001), and severe/life-threatening AE rates (69% vs 0%; P < .001) were significantly higher in patients with PHTN than in those without PHTN. CONCLUSIONS: There was a significantly higher mortality and severe/life-threatening AE rate in patients with PHTN than in those without PHTN. SAAs in patients with PHTN need to be managed very cautiously, given the risk of severe/life-threatening AEs after embolization.

Yttrium-90 Radioembolization of Unresectable Intrahepatic Cholangiocarcinoma: Long-Term Follow-up for a 136-Patient Cohort.

PURPOSE: Unresectable intrahepatic cholangiocarcinoma (ICC) signifies a poor prognosis with limited treatment options beyond systemic chemotherapy. This study's purpose was to evaluate the safety, efficacy, and potential for downstaging to resection of yttrium-90 (Y90) radioembolization for treatment of unresectable ICC. MATERIALS AND METHODS: From 2004 to 2020, 136 patients with unresectable ICC were treated with radioembolization at a single institution. Retrospective review was performed of a prospectively collected database. Outcomes were (1) biochemical and clinical toxicities, (2) local tumor response, (3) time to progression, and (4) overall survival (OS) after Y90. Univariate/multivariate survival analyses were performed. A subgroup analysis was performed to calculate post-resection recurrence and OS in patients downstaged to resection after Y90. RESULTS: Grade 3+ clinical and biochemical toxicities were 7.6% (n = 10) and 4.9% (n = 6), respectively. Best index lesion response was complete response in 2 (1.5%), partial response in 42 (32.1%), stable disease in 82 (62.6%), and progressive disease in 5 (3.8%) patients. Median OS was 14.2 months. Solitary tumor (P < 0.001), absence of vascular involvement (P = 0.009), and higher serum albumin (P < 0.001) were independently associated with improved OS. Eleven patients (8.1%) were downstaged to resection and 2 patients (1.5%) were bridged to transplant. R0-resection was achieved in 8/11 (72.7%). Post-resection median recurrence and OS were 26.3 months and 39.9 months, respectively. CONCLUSION: Y90 has an acceptable safety profile and high local disease control rates for the treatment of unresectable ICC. Downstaging to resection with > 3 years survival supports the therapeutic role of Y90 for unresectable ICC. LEVEL OF EVIDENCE: Level 3, single-arm single-center cohort study.

Antithrombotic Therapy After Venous Interventions: AJR Expert Panel Narrative Review.

Interventions for thrombotic and nonthrombotic venous disorders have increased with technical advances and more trained venous specialists. Antithrombotic therapy is essential to clinical and procedural success; however, postprocedural therapeutic regimens exhibit significant heterogeneity due to limited prospective randomized data and incomplete mechanistic understanding of the critical factors driving long-term patency. Postinterventional antithrombotic therapy for thrombotic venous disorders should adhere to existing venous thromboembolism management guidelines, which include 3-6 months of therapeutic anticoagulation at minimum and consideration of extended therapy in patients with higher risk of thrombosis because of procedural or patient factors. The added benefit of antiplatelet agents in the acute and intermediate period is unknown, having shown improved long-term stent patency in some retrospective studies. Dual- and/or triple-agent therapy should be limited based on individual risks of thrombosis and bleeding. The treatment of nonthrombotic disorders is more heterogeneous, though patients with limited flow, extensive stent material, or underlying prothrombotic states such as malignancy or chronic inflammation may benefit from single-agent or multiagent antithrombotic therapy. However, the agent, dose, and duration of therapy remain indeterminate. Future prospective studies are warranted to improve patient risk stratification and standardize postprocedural anti-thrombotic therapy in patients receiving venous interventions.

North American Practice-Based Recommendations for Transjugular Intrahepatic Portosystemic Shunts in Portal Hypertension.

Complications of portal hypertension, including ascites, gastrointestinal bleeding, hepatic hydrothorax, and hepatic encephalopathy, are associated with significant morbidity and mortality. Despite few high-quality randomized controlled trials to guide therapeutic decisions, transjugular intrahepatic portosystemic shunt (TIPS) creation has emerged as a crucial therapeutic option to treat complications of portal hypertension. In North America, the decision to perform TIPS involves gastroenterologists, hepatologists, and interventional radiologists, but TIPS creation is performed by interventional radiologists. This is in contrast to other parts of the world where TIPS creation is performed primarily by hepatologists. Thus, the successful use of TIPS in North America is dependent on a multidisciplinary approach and technical expertise, so as to optimize outcomes. Recently, new procedural techniques, TIPS stent technology, and indications for TIPS have emerged. As a result, practices and outcomes vary greatly across institutions and significant knowledge gaps exist. In this consensus statement, the Advancing Liver Therapeutic Approaches group critically reviews the application of TIPS in the management of portal hypertension. Advancing Liver Therapeutic Approaches convened a multidisciplinary group of North American experts from hepatology, interventional radiology, transplant surgery, nephrology, cardiology, pulmonology, and hematology to critically review existing literature and develop practice-based recommendations for the use of TIPS in patients with any cause of portal hypertension in terms of candidate selection, procedural best practices and, post-TIPS management; and to develop areas of consensus for TIPS indications and the prevention of complications. Finally, future research directions are identified related to TIPS for the management of portal hypertension.

Biliary Anatomy.

The hepatobiliary system is known to have high anatomic variability, as studies have shown variant rates of over 40% among individuals. This review will describe biliary anatomy and the most common anatomic variants, knowledge of which is critical to ensuring safe and effective biliary interventions.

Post-embolization outcomes of splenic artery pseudoaneurysms: A single-center experience.

PURPOSE: Splenic artery pseudoaneurysms (PSA) are relatively rare but associated with high mortality/morbidity when presenting acutely. Embolization has emerged as the treatment of choice. We aim to evaluate the outcomes of embolization for the treatment of splenic artery PSAs. METHODS: From 2007 to 2019, all patients that underwent embolization for splenic artery PSAs were included in this IRB-approved review. Evaluated outcomes included complications, morbidity/mortality rates, and 30-day white blood cell count. Student t-tests were performed to compare laboratory values before and after embolization. 5-year survival rates were estimated using Kaplan Meier methodology. RESULTS: A retrospective analysis of 24 patients (14 males, mean age 51 ± 19 years) who underwent splenic artery PSA embolization was performed. Fifteen PSA embolizations were performed in an emergent setting. There was technical success in 23/24 patients. Etiologies included trauma (10), pancreatitis (9), post-surgical (3), and malignancy (2). Post-embolization patients had a mean length of stay of 19 days and within 30 days, 9 patients developed leukocytosis (median of 14,800/µl). The 5-year survival rate of these patients was 89% [95% CI 75% - 100%]. Post-procedure, 4 patients developed grade 2 complications. Grade 3 complications were observed in 5 patients. One (4.2%) splenic abscess was identified. Of the 19 patients with follow-up imaging, 14 patients had splenic infarcts (5 infarcts were >50% of splenic volume). CONCLUSIONS: Splenic artery PSAs are encountered in the emergent setting and are most frequently secondary to trauma or pancreatitis. Embolization can be life-saving in these critically ill patients.