Treatment of advanced hepatocellular carcinoma (HCC) is challenging. Several randomized clinical trials are investigating the efficacy of systemic therapy, immunotherapy, and locoregional therapy as monotherapy or combined with other modalities in the treatment of HCC. Systemic therapy is the preferred treatment in advanced disease. To date, multiple first-line and second-line agents received Food and Drug Administration approval. For over a decade, sorafenib was the only first-line agent. In May 2020, combination of atezolizumab and bevacizumab has been approved as a first-line systemic regimen. Lenvatinib is another first-line agent that has multikinase activity. Second-line agents include cabozantinib, regorafenib, ramucirumab, and nivolumab. Adoptive cell transfer therapy is a highly specific immunotherapy that has shown antitumor activity against HCC. Oncolytic viruses are genetically modified viruses that infect cancer cells and induce apoptosis. Locoregional therapies such as transarterial chemoembolization and radioembolization have shown a potential benefit in selected patients with advanced HCC. In this review, we aim to summarize the treatment options available for advanced HCC.

Brown-Sequard Syndrome is a neurologic disorder caused by partial spinal cord injury and disruption of the corticospinal tract, dorsal columns, and spinothalamic tract. We present a 32-year-old male with partial T11-12 cord transection due to a penetrating knife injury. In addition to the classical neurological symptoms of Brown-Sequard Syndrome, he also exhibited ipsilateral peripheral vasodilatation below the level of injury. This finding is attributed to the disruption of the intermediolateral columns of the spinal cord and impaired sympathetic tone on the peripheral vasculature. Awareness of this finding can raise the radiologist's suspicion for spinal cord injury in the setting of trauma and peripheral vasodilation.

Image fusion may be useful in any procedure where previous imaging such as positron emission tomography, magnetic resonance imaging, or contrast-enhanced computed tomography (CT) defines information that is referenced to the procedural imaging, to the needle or catheter, or to an ultrasound transducer. Fusion of prior and intraoperative imaging provides real-time feedback on tumor location or margin, metabolic activity, device location, or vessel location. Multimodality image fusion in interventional radiology was initially introduced for biopsies and ablations, especially for lesions only seen on arterial phase CT, magnetic resonance imaging, or positron emission tomography/CT but has more recently been applied to other vascular and nonvascular procedures. Two different types of platforms are commonly used for image fusion and navigation: (1) electromagnetic tracking and (2) cone-beam CT. Both technologies would be reviewed as well as their strengths and weaknesses, indications, when to use one vs the other, tips and guidance to streamline use, and early evidence defining clinical benefits of these rapidly evolving, commercially available and emerging techniques.

Lymphatic malformations (LMs) are rare congenital anomalies. LMs are often refractory to standard treatments, including surgical resection, debulking, and sclerotherapy. Use of sildenafil, a phosphodiesterase-5 inhibitor, for treatment of pediatric LMs has been reported with demonstrated benefit to some patients. This case series reports treatment of three patients (aged 14-37 years) suffering from complicated or refractory LMs with a low-dose oral phosphodiesterase-5 inhibitor, resulting in significant clinical improvement.

Interventional oncology is a rapidly emerging field in the treatment of cancer. Minimally invasive techniques such as transarterial embolization with chemotherapeutic and radioactive agents are established therapies and are found in multiple guidelines for the management of primary and metastatic liver lesions. Percutaneous ablation is also an alternative to surgery for small liver, renal, and pancreatic tumors. Recent research in the niche of interventional oncology has focused on improving outcomes of established techniques in addition to the development of novel therapies. In this review, we address the recent and current advancements in devices, technologies, and techniques of chemoembolization and ablation: thermal ablation, histotripsy, high-intensity focused ultrasound, embolization strategies, liquid embolic agents, and local immunotherapy/antiviral therapies.

Inferior vena cava (IVC) filters are posited to effect flow dynamics, causing turbulence, vascular remodeling and eventual thrombosis; however, minimal data exists evaluating hemodynamic effects of IVC filters in vivo. The purpose of this study was to determine differences in hemodynamic flow parameters acquired with two-dimension (2D)-perfusion angiography before and after IVC filter placement or retrieval. 2D-perfusion images were reconstructed retrospectively from digital subtraction angiography from a cohort of 37 patients (13F/24M) before and after filter placement (n = 18) or retrieval (n = 23). Average dwell time was 239.5 ± 132.1 days. Changes in the density per pixel per second within a region of interest (ROI) were used to calculate contrast arrival time (AT), time-to-peak (TTP), wash-in-rate (WIR), and mean transit time (MTT). Measurements were obtained superior to, inferior to, and within the filter. Differences in hemodynamic parameters before and after intervention were compared, as well as correlation between parameters versus filter dwell time. A P value with Bonferroni correction of <.004 was considered statistically significant. After placement, there was no difference in any 2D-perfusion variable. After retrieval, ROIs within and inferior to the filter showed a significantly shorter TTP (1.7 vs 1.4 s, P = .004; 1.5 vs 1.3 s, P = .001, respectively) and MTT (1.7 vs 1.4 s, P = .003; 1.5 vs 1.2 s, P = .002, respectively). Difference in variables showed no significant correlation when compared to dwell time. 2D-perfusion angiography is feasible to evaluate hemodynamic effects of IVC filters in vivo. TTP and MTT within and below the filter after retrieval were significantly changed, without apparent correlation to dwell time, suggesting a functional hemodynamic delay secondary to filter presence.

Background

Patients diagnosed with locally advanced pancreatic cancer are usually not eligible for surgical resection because of significant vascular involvement. Stereotactic body radiation therapy and chemotherapy are the treatments recommended by the National Comprehensive Cancer Network criteria. For patients who do not respond to or tolerate stereotactic body radiation therapy and/or chemotherapy, a new option is irreversible electroporation. Irreversible electroporation is a nonthermal minimally invasive ablation technique that uses electrical pulses to induce apoptosis of tumor cells without damage to the extracellular matrix, thus preserving ducts and vessels. Irreversible electroporation requires very precise needle placement, which has limited its ubiquitous use. Intraprocedural cone-beam computed tomography with navigation can be fused with previous imaging to provide real-time tumor navigation capabilities during the procedure to allow for more accurate needle placement and treatment. Here, we present a patient who underwent percutaneous irreversible electroporation with intraprocedural cone-beam computed tomography fusion guidance to treat his pancreatic cancer.

Case presentation

The patient, an 88-year-old White male, initially presented with abdominal pain, and was ultimately diagnosed with locally advanced pancreatic cancer. He has an excellent performance status and no other comorbidities. He was started on chemotherapy and radiation therapy, with good response. However, continued vascular involvement of the tumors precluded him from safe surgical resection. The patient underwent irreversible electroporation with intraprocedural cone-beam computed tomography fusion navigation. The primary lesion demonstrates no residual tumor, and the soft tissue involvement of the adjacent vasculature has stabilized.

Conclusions

Although not curative on its own, irreversible electroporation holds promise as a treatment option for patients with locally advanced pancreatic cancer to increase downsizing to curative surgery or increase quality of life. Cone-beam computed tomography navigation can improve irreversible electroporation by providing guidance during needle guidance. Image fusion with previous advanced imaging can improve lesion visualization and targeting, thereby improving the effectiveness of irreversible electroporation.

Interventional radiology plays an integral role in the management of massive and recurrent submassive hemoptysis. Risks of bronchial artery embolization (BAE) are well described and include spinal ischemia and paralysis, most often related to nontarget embolization of the artery of Adamkiewicz or other large radiculomedullary artery supplying the anterior spinal artery. There is increasing literature regarding spinal infarction following BAE when arterial supply to the spinal cord was not evident. The existence of unrecognized patient comorbidities may further contribute to procedural risks.

Purpose The purpose of this study was to (1) develop a novel tissue-mimicking thermochromic (TMTC) phantom that permanently changes colour from white to magenta upon heating above ablative temperatures, and (2) assess its utility for specific applications in evaluating thermal therapy devices. Materials and methods Polyacrylamide gel mixed with thermochromic ink was custom made to produce a TMTC phantom that changes its colour upon heating above biological ablative temperatures (> 60 °C). The thermal properties of the phantom were characterised, and compared to those of human tissue. In addition, utility of this phantom as a tool for the assessment of laser and microwave thermal ablation was examined. Results The mass density, thermal conductivity, and thermal diffusivity of the TMTC phantom were measured as 1033 ± 1.0 kg/m(3), 0.590 ± 0.015 W/m.K, and 0.145 ± 0.002 mm(2)/s, respectively, and found to be in agreement with reported values for human soft tissues. Heating the phantom with laser and microwave ablation devices produced clearly demarcated regions of permanent colour change geographically corresponding to regions with temperature elevations above 60 °C. Conclusion The TMTC phantom provides direct visualisation of ablation dynamics, including ablation volume and geometry as well as peak absolute temperatures within the treated region post-ablation. This phantom can be specifically tailored for different thermal therapy modalities, such as radiofrequency, laser, microwave, or therapeutic ultrasound ablation. Such modality-specific phantoms may enable better quality assurance, device characterisation, and ablation parameter optimisation, or optimise the study of dynamic heating parameters integral to drug device combination therapies relying upon heat.

Hypoxia-inducible factor 1 alpha (HIF-1α) is a transcription factor that regulates the cellular response to hypoxia and is upregulated in all types of solid tumor, leading to tumor angiogenesis, growth, and resistance to therapy. Hepatocellular carcinoma (HCC) is a highly vascular tumor, as well as a hypoxic tumor, due to the liver being a relatively hypoxic environment compared to other organs. Trans-arterial chemoembolization (TACE) and trans-arterial embolization (TAE) are locoregional therapies that are part of the treatment guidelines for HCC but can also exacerbate hypoxia in tumors, as seen with HIF-1α upregulation post-hepatic embolization. Hypoxia-activated prodrugs (HAPs) are a novel class of anticancer agent that are selectively activated under hypoxic conditions, potentially allowing for the targeted treatment of hypoxic HCC. Early studies targeting hypoxia show promising results; however, further research is needed to understand the effects of HAPs in combination with embolization in the treatment of HCC. This review aims to summarize current knowledge on the role of hypoxia and HIF-1α in HCC, as well as the potential of HAPs and liver-directed embolization.