[CME-Sonography 104: Angiomyolipomas].

CME-Sonography 104: Angiomyolipomas Angiomyolipomas are the most common benign kidney tumors. Approximately 80 % are spontaneously occurring tumors, the majority <1.0 cm (approximately 54 %).

European Thyroid Association and Cardiovascular and Interventional Radiological Society of Europe 2021 Clinical Practice Guideline for the Use of Minimally Invasive Treatments in Malignant Thyroid Lesions.

The growing detection of papillary thyroid microcarcinomas (PTMCs) is paralleled by an increase in surgical procedures. Due to the frequent indolent nature, cost, and risk of surgery, active surveillance (AS) and ultrasound-guided minimally invasive treatments (MITs) are in suitable cases of incidental PTMC proposed as alternatives to thyroidectomy. Surgery and radioiodine are the established treatments for relapsing cervical differentiated thyroid carcinoma (DTC) metastases.

Multiple stent delivery system Multi-LOC, a new technology for spot-stenting of the femoropopliteal artery - proof of concept study in a preclinical large animal model.

Background: A new stent system was studied in a porcine model to evaluate its feasibility for spot-stenting of the femoropopliteal artery.

Materials And Methods: In a preliminary study in a single pig, handling and mechanical features of the novel multiple stent delivery system were tested. The Multi-LOC system demonstrated great feasibility regarding its pushability, trackability, and crossability.

Validation of VX2 as a Hepatocellular Carcinoma Model: Comparison of the Molecular Reaction of VX2 and HepG2 Tumor Cells to Sorafenib In Vitro.

As there is currently no superior hepatocellular carcinoma (HCC) model with percutaneous vascular access for transarterial treatments available, the VX2 rabbit model is frequently used for in vivo investigations on liver carcinoma. However, the VX2 cell line was derived from a virus-induced skin papilloma that can form carcinosarcoma in liver of rabbits and the transferability of obtained results to HCC treatment remains open. Here we compared the most frequently investigated human HCC model cell line, HepG2, with VX2 cells in vitro in terms of sensitivity towards the broad specificity kinase inhibitor sorafenib and responsiveness to the addition of platelet-derived growth factor AB (PDGF-AB), vascular endothelial growth factor (VEGF) and hepatic growth factor (HGF), as well as insulin and interleukin-1β (IL1β).

Modified transarterial chemoembolization with locoregional administration of sorafenib for treating hepatocellular carcinoma: feasibility, efficacy, and safety in the VX-2 rabbit liver tumor model.

Purpose: We aimed to assess the feasibility, efficacy and safety of a local application of sorafenib within a conventional transarterial chemoembolization in the VX-2 tumor-bearing rabbit model.

Methods: VX-2 tumors were induced in the left liver lobe of 10 New Zealand White rabbits. After two weeks, growth was verified by contrast-enhanced computed tomography (CT).

Is There Any Evidence for a Role of Local Treatment in Cholangiocarcinoma?

Background: Most cholangiocarcinomas (CCA) are locally advanced and unresectable at the time of diagnosis. Currently, chemotherapy combining gemcitabine with a platinum agent is the recommended first-line treatment regimen for advanced biliary tract cancer. However, median overall survival is only approximately 1 year.

Efficacy and safety of image-guided interstitial single fraction high-dose-rate brachytherapy in the management of metastatic malignant melanoma.

Purpose: Computed tomography (CT) or magnetic resonance imaging (MRI) guided brachytherapy provides high tumor control rates in hepatocellular carcinoma (HCC) and colorectal liver metastases. In contrast to thermal ablation methods such as radiofrequency ablation (RFA), much less restrictions apply with respect to tumor location or size. In this study, we determined the efficacy and safety of CT- or MRI-guided brachytherapy in metastatic melanoma.

Prophylactic embolization of the cystic artery prior to radioembolization of liver malignancies--an evaluation of necessity.

Purpose: Prior to radioembolization (RE) of hepatic tumors, many centers prophylactically occlude the cystic artery (CA) during evaluation angiography (EVA) to prevent radiation-induced cholecystitis. There is no conclusive evidence for the protective effect of CA embolization and it bears the risk of inducing ischemic cholecystitis. The aim of this study is to evaluate the justification for CA embolization by comparing clinical and morphologic imaging parameters between patients undergoing coil occlusion of the cystic artery (COCA) and those with uncoiled CA (UCCA).

The retrograde transvenous push-through method: a novel treatment of peripheral arteriovenous malformations with dominant venous outflow.

Purpose: To evaluate the efficacy and safety of a novel retrograde transvenous embolization technique of peripheral arteriovenous malformations (AVMs) using Onyx.

Materials And Methods: We conducted a retrospective analysis of all patients who underwent transvenous retrograde Onyx embolization of peripheral AVMs with dominant venous outflow over a 29-month period. The embolization is aimed at retrograde filling of the nidus after building a solid plug in the dominant venous outflow (push-through).

Time-resolved perfusion imaging at the angiography suite: preclinical comparison of a new flat-detector application to computed tomography perfusion.

Objectives: The objective of this study was to compare the parameter maps of a new flat-panel detector application for time-resolved perfusion imaging in the angiography room (FD-CTP) with computed tomography perfusion (CTP) in an experimental tumor model.

Materials And Methods: Twenty-four VX2 tumors were implanted into the hind legs of 12 rabbits. Three weeks later, FD-CTP (Artis zeego; Siemens) and CTP (SOMATOM Definition AS +; Siemens) were performed.

Safety and efficacy of target vessel catheterization with the new steerable microcatheter Direxion compared with a standard microcatheter: a prospective, preclinical trial.

Purpose: To assess the potential of a steerable microcatheter in a comparative preclinical trial.

Methods: A total of 100 small target vessels of the lower limbs with a maximum diameter of 3 mm were prospectively randomized to catheterize with either the preshaped torqueable Direxion™ (J tip shape; Boston Scientific, Natick, MA) or a similarly steam-shaped Renegade™ microcatheter (Boston Scientific) in a porcine model. Catheterization was first performed in combination with a microguidewire and afterwards without.

CT-assisted transfemoral intrahepatic portosystemic shunt in a long duration follow-up: A case report.

Background: Transjugular intrahepatic portosystemic shunt (TIPS) in patients with portal hypertension may be considered as a rescue therapy in case of recurrent variceal bleeding or failure of endoscopic management.

Case Reports: We present a case of a patient with massive gastroesophageal variceal bleeding refractory to numerous endoscopic treatments in which TIPS was considered in an attempt to decrease the risk of potentially fatal rebleeding. Standard TIPS procedure was not feasible due to altered anatomy of the liver resulting from right hemidiaphragmatic paresis.

Superiority of proximal embolization of the gastroduodenal artery with the Amplatzer vascular plug 4 before yttrium-90 radioembolization: a retrospective comparison with coils in 134 patients.

Purpose: To evaluate the effectiveness of proximal embolization of the gastroduodenal artery (GDA) using the Amplatzer Vascular Plug 4 (AVP 4) compared with pushable coils to avoid hepaticoenteric collaterals of the GDA stump, which may serve as pathways for nontarget embolization.

Materials And Methods: One hundred thirty-four patients scheduled for 90-yttrium radioembolization (Y-90 RE) using either plugs (n = 67) or standard coils (n = 67) for GDA occlusion were retrospectively analyzed. Parameters recorded were length of the perfused GDA stump, distance device to the GDA origin, perfused proximal side branches after embolization, and durability of vessel occlusion at Y-90 RE.

Predictive value of intratumoral 99mTc-macroaggregated albumin uptake in patients with colorectal liver metastases scheduled for radioembolization with 90Y-microspheres.

Unlabelled: (90)Y radioembolization is a promising therapy for patients with primary and secondary liver malignancies. Pretherapeutic assessment consists of hepatic angiography and (99m)Tc-macroaggregated albumin ((99m)Tc-MAA) perfusion scintigraphy to estimate the liver-to-lung shunt and exclude extrahepatic (99m)Tc-MAA deposition. However, the predictive value of intratumoral (99m)Tc-MAA uptake remains unclear.

Effectiveness of repeat angiographic assessment in patients designated for radioembolization using yttrium-90 microspheres with initial extrahepatic accumulation of technitium-99m macroaggregated albumin: a single center's experience.

Purpose: To evaluate the efficacy of a workflow consisting of repeat assessment in patients planned for yttrium-90 ((90)Y) radioembolization in case of nontarget visceral technetium-99m ((99m)Tc)-macroaggregated albumin (MAA) accumulation despite initial prophylactic coil embolization of nonhepatic arteries.

Materials And Methods: In 341 patients with primary and secondary liver cancer, pretreatment hepatic angiograms, as well as single-photon emission computed tomography coregistered with magnetic resonance imaging scans, were obtained. Extrahepatic tracer deposition was identified in 33 patients (9.

Matched-pair comparison of radioembolization plus best supportive care versus best supportive care alone for chemotherapy refractory liver-dominant colorectal metastases.

Purpose: This study was designed to evaluate overall survival after radioembolization or best supportive care (BSC) in patients with chemotherapy-refractory liver-dominant metastatic colorectal cancer (mCRC).

Methods: This was a matched-pair comparison of patients who received radioembolization plus BSC or BSC alone for extensive liver disease. Twenty-nine patients who received radioembolization were retrospectively matched with a contemporary cohort of >500 patients who received BSC from 3 centers in Germany.

[Radioembolization with (90)Y-labeled microspheres: post-therapeutic therapy validation with Bremsstrahlung-SPECT].

During the last years angiographic Selective Internal Radiotherapy (SIRT) with (90)Y-labelled microspheres has become a common technique for the local-ablative treatment of cancer patients. SIRT is a palliative therapy concept for the treatment of liver malignancies. As a result of (90)Y-decay as β(-)-emitter without a concomitant gamma radiation, Bremsstrahlung imaging is needed to validate the distribution achieved by radioembolisation.

Angiography in the isolated perfused kidney: radiological evaluation of vascular protection in tissue ablation by nonthermal irreversible electroporation.

Purpose: The nonthermal irreversible electroporation (NTIRE) is a novel nonthermal tissue ablation technique by local application of high-voltage current within microseconds leading to a delayed apoptosis. The purpose of this experimental study was the first angiographic evaluation of the acute damage of renal vascular structure in NTIRE.

Methods: Results of conventional dynamic digital substraction angiography (DSA) and visualization of the terminal vascular bed of renal parenchyma by high-resolution X-ray in mammography technique were evaluated before, during, and after NTIRE of three isolated perfused porcine ex vivo kidneys.

Value of diffusion weighted MR imaging as an early surrogate parameter for evaluation of tumor response to high-dose-rate brachytherapy of colorectal liver metastases.

Background: To assess the value of diffusion weighted imaging (DWI) as an early surrogate parameter for treatment response of colorectal liver metastases to image-guided single-fraction ¹⁹²Ir-high-dose-rate brachytherapy (HDR-BT).

Methods: Thirty patients with a total of 43 metastases underwent CT- or MRI-guided HDR-BT. In 13 of these patients a total of 15 additional lesions were identified, which were not treated at the initial session and served for comparison.

Prevention of intraprocedural puncture site bleeding during arterial port implantation by use of a suture-mediated arterial closure system: a prospective randomized trial.

Purpose: To investigate a modified technique for arterial port placement that uses a suture-mediated closure system with the aim to reduce delays caused by intraprocedural oozing around the catheter.

Materials And Methods: Forty consecutive patients (age, 63.9 y ± 11.

Computed tomographic criteria for the discrimination of subcentimeter lung nodules in patients with soft-tissue sarcomas.

The aim of this study was to identify criteria for nodule characterization on chest computed tomography in patients with soft tissue sarcomas. In 195 patients, a total of 194 benign and 117 malignant subcentimeter lung nodules were retrospectively analyzed according to lesion size, shape, margins, density, and localization. Benign lesions more frequently displayed complex shape and were of ground-glass density (P<.

Advances in regional chemotherapy of the liver.

Introduction: Primary and secondary liver tumors resemble some of the most common causes of cancer and represent a major clinical problem owing to the poor prognosis. First-line therapeutic concepts are mainly based on surgical resection and/or systemic chemotherapy (SCT). However, many patients are not suitable for surgery or have failed SCT, although the total tumor load is still limited, which makes a regional therapy approach appealing.

Advantages and disadvantages of the Amplatzer Vascular Plug IV in visceral embolization: report of 50 placements.

Purpose: We describe our initial clinical experience in artificial embolization with the Amplatzer Vascular Plug IV (VP IV), a further development of the Vascular Plug family already in routine use.

Methods: Results from 50 embolization procedures conducted with the VP IV in 44 patients are summarized.

Results: All 50 embolizations were successful, although two required the technique to be modified because of problems with jamming of the screw thread and thus with disconnection of the plug.