Locoregional Therapies for Hepatocellular Carcinoma prior to Liver Transplant: Comparative Pathologic Necrosis, Radiologic Response, and Recurrence.

PURPOSE: To compare pathologic tumor necrosis rates after locoregional therapies (LRTs) for hepatocellular carcinoma (HCC) prior to liver transplantation and evaluate radiologic-pathologic correlation along with posttransplant HCC recurrence. MATERIALS AND METHODS: Consecutive patients with solitary HCC bridged or downstaged with LRT from 2010 to 2022 were included. LRTs were transarterial chemoembolization (TACE), radioembolization (yttrium-90 [90Y]), ablation, and stereotactic body radiotherapy (SBRT). Upfront combination therapy options were TACE/ablation and TACE/SBRT. Subsequent therapy crossover due to local recurrence was allowed. Posttreatment imaging closest to the time of transplant, explant histopathologic necrosis, and tumor recurrence after transplant were reviewed. RESULTS: Seventy-three patients met inclusion criteria, of whom 5 (7%) required downstaging. 90Y alone (n = 36) and multimodal therapy (pooled upfront combination and crossover therapy, n = 23) resulted in significantly greater pathologic necrosis compared with TACE alone (n = 14; P = .01). High dose 90Y radiation segmentectomy (≥190 Gy; n = 27) and TACE/ablation (n = 7) showed highest rates of complete pathologic necrosis (CPN)-63% (n = 17) and 71% (n = 5), respectively. Patients with CPN had a mean lesion size of 2.5 cm, compared with 3.2 cm without CPN (P = .04), irrespective of LRT modality. HCC recurrence was more common in patients without CPN (16%, 6/37) than in those with CPN (3%, 1/36; P = .11). Using Liver Imaging Reporting and Data System (LI-RADS), a nonviable imaging response was 75% sensitive and 57% specific for CPN. CONCLUSIONS: Radiation segmentectomy and multimodal therapy significantly improved CPN rates compared with TACE alone. A LI-RADS treatment response of nonviable did not confidently predict CPN.

Portal Vein Thrombosis In Cirrhosis: Interventional Treatment Options.

PURPOSE OF REVIEW: Portal vein thrombosis (PVT) is a frequent consequence of cirrhosis and its management is variable and controversial. Herein we highlight interventional treatment options and outcomes, together with mention of the physiology, presentation and imaging of PVT. RECENT FINDINGS: Utilization of transjugular intrahepatic portosystemic shunt (TIPS) for acute and chronic PVT is expanding. In acute PVT, TIPS improves hepatopetal flow which promotes thrombus resorption and prevents rethrombosis. The TIPS also functions as a conduit for thrombectomy devices and allows for embolization of variceal shunts. Chronic PVT is a relative contraindication to liver transplant. Portal vein recanalization (PVR) TIPS restores flow in a previously occluded portal vein, allowing for a conventional end-to-end portal vein anastomosis at transplant. PVR TIPS is technically demanding and often requires percutaneous splenic vein access for portal venous recanalization. Selection of endovascular PVT treatment varies with the age (acute or chronic) and the extent of thrombus, along with presenting symptoms and transplant candidacy.

Simultaneous static and cine nonenhanced MR angiography using radial sampling and highly constrained back projection reconstruction.

PURPOSE: To describe a pulse sequence for simultaneous static and cine nonenhanced magnetic resonance angiography (NEMRA) of the peripheral arteries. METHODS: The peripheral arteries of 10 volunteers and 6 patients with peripheral arterial disease (PAD) were imaged with the proposed cine NEMRA sequence on a 1.5 Tesla (T) system. The impact of multi-shot imaging and highly constrained back projection (HYPR) reconstruction was examined. The propagation rate of signal along the length of the arterial tree in the cine nonenhanced MR angiograms was quantified. RESULTS: The cine NEMRA sequence simultaneously provided a static MR angiogram showing vascular anatomy as well as a cine display of arterial pulse wave propagation along the entire length of the peripheral arteries. Multi-shot cine NEMRA improved temporal resolution and reduced image artifacts. HYPR reconstruction improved image quality when temporal reconstruction footprints shorter than 100 ms were used (P < 0.001). Pulse wave propagation within the arterial tree as displayed by cine NEMRA was slower in patients with PAD than in volunteers. CONCLUSION: Simultaneous static and cine NEMRA of the peripheral arteries is feasible. Multi-shot acquisition and HYPR reconstruction can be used to improve arterial conspicuity and temporal resolution.

Evaluating peripheral arterial disease with unenhanced quiescent-interval single-shot MR angiography at 3 T.

OBJECTIVE: The objective of our study was to assess the diagnostic performance of quiescent-interval single-shot (QISS) MR angiography (MRA) at 3 T for the evaluation of chronic lower limb ischemia. SUBJECTS AND METHODS: For this prospective study, 25 patients referred for lower extremity angiography for suspected or known chronic peripheral arterial disease were imaged on a 3-T system using QISS MRA. Contrast-enhanced MRA of the lower extremities was acquired at 3 T for each patient at the time of the initial visit and served as the noninvasive reference standard. Two blinded reviewers separately graded the degree of arterial stenosis. The sensitivity and specificity of QISS MRA for the determination of significant (≥ 50%) stenosis were calculated against contrast-enhanced MRA. Subsequent selective digital subtraction angiography (DSA) was performed and reviewed in nine patients. RESULTS: QISS MRA exhibited diagnostic performance nearly equivalent to that of contrast-enhanced MRA and also showed strong correlation with findings on DSA. Segment-based analysis revealed that, for the two reviewers, QISS MRA had sensitivities of 95.9% (142 of 148 segments) and 93.5% (145 of 155 segments) and specificities of 98.5% (595 of 604 segments) and 97.0% (578 of 596 segments) on comparison with contrast-enhanced MRA. CONCLUSION: QISS MRA maintains high diagnostic performance at 3 T despite the challenges inherent to image acquisition at higher field strengths.

Liver Venous Deprivation for Rapid Liver Hypertrophy Before Major Hepatectomy: A Case Report.

Liver venous deprivation (LVD) is an emerging, minimally invasive strategy to induce rapid liver hypertrophy of the future liver remnant (FLR) before a major hepatectomy. LVD (aka "double vein embolization") entails same-session percutaneous embolization of the portal and hepatic veins of the planned liver resection. This report discusses LVD's utilization and technical challenges in managing a 49-year-old male with recurrent multifocal colorectal liver metastases (CRLM). The patient initially underwent neoadjuvant FOLFOX chemotherapy followed by a simultaneous laparoscopic sigmoid colectomy and liver surgery (microwave ablation of segment V and wedge resections of segment one and IVb), followed by completion of chemotherapy. The patient had an R0 resection with clear colon and liver surgical margins. Nine months after the initial surgery, the patient had a rise in tumor markers, and surveillance imaging demonstrated recurrence of liver metastases in segments I and V. LVD was performed by interventional radiology, which led to a 28% increase in FLR (segments II, III, and IV); initially measuring 464 cm3 before LVD and measuring 594 cm3 on post-procedure day 21. The patient underwent right hemi-hepatectomy and caudate resection on post-procedure day 29. The patient did not have any complications and was discharged on postoperative day 6. The patient remains disease-free with no evidence of recurrence at 12 months follow-up.

Large Bore Portal Vein Thrombectomy: An Inari FlowTriever Case Series.

PURPOSE: Portal vein thrombus (PVT) can worsen portal hypertension and hepatic decompensation in patients with cirrhosis and impact liver transplant outcomes. This retrospective case series describes large bore mechanical thrombectomy of PVT with the Inari FlowTriever device during, or remotely after, transjugular intrahepatic portosystemic shunt (TIPS) placement. MATERIALS AND METHODS: Ten patients with PVT were treated with large bore thrombectomy. All patients had underlying cirrhosis, complicated by portal hypertension with acute/subacute PVT. Thrombectomy was performed either with TIPS placement, or via a previously placed thrombosed shunt. Median time from TIPS placement to thrombectomy was 3 years. RESULTS: Thrombectomy was technically successful in all patients with a majority achieving complete resolution of PVT in a single session. During mean follow-up of 13.3 months, all patients achieved complete resolution of PVT without recurrence. CONCLUSION: Large bore mechanical thrombectomy together with TIPS is a feasible and effective treatment of acute/subacute PVT in cirrhotic patients with portal hypertension, often with complete resolution in a single session.

Management of Complicated Appendicitis in the Pediatric Population: When Surgery Doesn't Cut It.

The management of complicated appendicitis in children has evolved significantly over the last century. What initially was a surgeon's dilemma is becoming the interventional radiologist's task because image-guided percutaneous drainage of abscesses from a ruptured appendix obviates the need for urgent surgery and allows for selective interval appendectomy at the surgeon's discretion (versus conservative nonoperative management in selected cases). This paradigm shift places the onus on the interventional radiologist to recognize when the procedure is emergently indicated and to be cognizant of the special needs of a pediatric patient.

Percutaneous sclerotherapy of cystic lesions.

With modern cross-sectional imaging techniques, cystic lesions are very common and usually incidental findings, especially if small. However, when cysts enlarge, become infected, bleed, or undergo torsion, they can be symptomatic, and percutaneous drainage can be effective in the management. When cysts recur after aspiration, which is often the case for hepatic and renal cysts, cyst sclerosis or surgical unroofing may be required. This article describes the indications for and technical aspects of percutaneous sclerotherapy of cystic lesions of multiple organ systems.

Concave Margin Sign on CT as an Indication of Ascites.

Ascites is found in a variety of conditions, both acute and chronic, and computed tomography (CT) is usually successful in detecting its presence. We reviewed the CT images from a three-month window of patients in order to evaluate the prevalence and utility of a new radiographic sign for diagnosing ascites.