Ultrasound and x-ray imageable poloxamer-based hydrogel for loco-regional therapy delivery in the liver.

Intratumoral injections have the potential for enhanced cancer treatment efficacy while reducing costs and systemic exposure. However, intratumoral drug injections can result in substantial off-target leakage and are invisible under standard imaging modalities like ultrasound (US) and x-ray. A thermosensitive poloxamer-based gel for drug delivery was developed that is visible using x-ray imaging (computed tomography (CT), cone beam CT, fluoroscopy), as well as using US by means of integrating perfluorobutane-filled microbubbles (MBs). MBs content was optimized using tissue mimicking phantoms and ex vivo bovine livers. Gel formulations less than 1% MBs provided gel depositions that were clearly identifiable on US and distinguishable from tissue background and with minimal acoustic artifacts. The cross-sectional areas of gel depositions obtained with US and CT imaging were similar in studies using ex vivo bovine liver and postmortem in situ swine liver. The gel formulation enhanced multimodal image-guided navigation, enabling fusion of ultrasound and x-ray/CT imaging, which may enhance targeting, definition of spatial delivery, and overlap of tumor and gel. Although speculative, such a paradigm for intratumoral drug delivery might streamline clinical workflows, reduce radiation exposure by reliance on US, and boost the precision and accuracy of drug delivery targeting during procedures. Imageable gels may also provide enhanced temporal and spatial control of intratumoral conformal drug delivery.

X-ray imageable, drug-loaded hydrogel that forms at body temperature for image-guided, needle-based locoregional drug delivery.

Liver cancer ranks as the fifth leading cause of cancer-related death globally. Direct intratumoral injections of anti-cancer therapeutics may improve therapeutic efficacy and mitigate adverse effects compared to intravenous injections. Some challenges of intratumoral injections are that the liquid drug formulation may not remain localized and have unpredictable volumetric distribution. Thus, drug delivery varies widely, highly-dependent upon technique. An X-ray imageable poloxamer 407 (POL)-based drug delivery gel was developed and characterized, enabling real-time feedback. Utilizing three needle devices, POL or a control iodinated contrast solution were injected into an ex vivo bovine liver. The 3D distribution was assessed with cone beam computed tomography (CBCT). The 3D distribution of POL gels demonstrated localized spherical morphologies regardless of the injection rate. In addition, the gel 3D conformal distribution could be intentionally altered, depending on the injection technique. When doxorubicin (DOX) was loaded into the POL and injected, DOX distribution on optical imaging matched iodine distribution on CBCT suggesting spatial alignment of DOX and iodine localization in tissue. The controllability and localized deposition of this formulation may ultimately reduce the dependence on operator technique, reduce systemic side effects, and facilitate reproducibility across treatments, through more predictable standardized delivery.

X-ray imageable, drug-loaded hydrogel that forms at body temperature for image-guided, needle- based locoregional drug delivery.

Liver cancer ranks as the fifth leading cause of cancer-related death globally. Direct intratumoral injections of anti-cancer therapeutics may improve therapeutic efficacy and mitigate adverse effects compared to intravenous injections. Some challenges of intratumoral injections are that the liquid drug formulation may not remain localized and have unpredictable volumetric distribution. Thus, drug delivery varies widely, highly-dependent upon technique. An x-ray imageable poloxamer 407 (POL)-based drug delivery gel was developed and characterized, enabling real-time feedback. Utilizing three needle devices, POL or a control iodinated contrast solution were injected into an ex vivo bovine liver. The 3D distribution was assessed with cone beam computed tomography (CBCT). The 3D distribution of POL gels demonstrated localized spherical morphologies regardless of the injection rate. In addition, the gel 3D conformal distribution could be intentionally altered, depending on the injection technique. When doxorubicin (DOX) was loaded into the POL and injected, DOX distribution on optical imaging matched iodine distribution on CBCT suggesting spatial alignment of DOX and iodine localization in tissue. The controllability and localized deposition of this formulation may ultimately reduce the dependence on operator technique, reduce systemic side effects, and facilitate reproducibility across treatments, through more predictable standardized delivery.

Smartphone Augmented Reality Outperforms Conventional CT Guidance for Composite Ablation Margins in Phantom Models.

PURPOSE: To develop and evaluate a smartphone augmented reality (AR) system for a large 50-mm liver tumor ablation with treatment planning for composite overlapping ablation zones. MATERIALS AND METHODS: A smartphone AR application was developed to display tumor, probe, projected probe paths, ablated zones, and real-time percentage of the ablated target tumor volume. Fiducial markers were attached to phantoms and an ablation probe hub for tracking. The system was evaluated with tissue-mimicking thermochromic phantoms and gel phantoms. Four interventional radiologists performed 2 trials each of 3 probe insertions per trial using AR guidance versus computed tomography (CT) guidance approaches in 2 gel phantoms. Insertion points and optimal probe paths were predetermined. On Gel Phantom 2, serial ablated zones were saved and continuously displayed after each probe placement/adjustment, enabling feedback and iterative planning. The percentages of tumor ablated for AR guidance versus CT guidance, and with versus without display of recorded ablated zones, were compared among interventional radiologists with pairwise t-tests. RESULTS: The means of percentages of tumor ablated for CT freehand and AR guidance were 36% ± 7 and 47% ± 4 (P = .004), respectively. The mean composite percentages of tumor ablated for AR guidance were 43% ± 1 (without) and 50% ± 2 (with display of ablation zone) (P = .033). There was no strong correlation between AR-guided percentage of ablation and years of experience (r < 0.5), whereas there was a strong correlation between CT-guided percentage of ablation and years of experience (r > 0.9). CONCLUSIONS: A smartphone AR guidance system for dynamic iterative large liver tumor ablation was accurate, performed better than conventional CT guidance, especially for less experienced interventional radiologists, and enhanced more standardized performance across experience levels for ablation of a 50-mm tumor.

Hydrogel drug delivery systems for minimally invasive local immunotherapy of cancer.

Although systemic immunotherapy has achieved durable responses and improved survival for certain patients and cancer types, low response rates and immune system-related systemic toxicities limit its overall impact. Intratumoral (intralesional) delivery of immunotherapy is a promising technique to combat mechanisms of tumor immune suppression within the tumor microenvironment and reduce systemic drug exposure and associated side effects. However, intratumoral injections are prone to variable tumor drug distribution and leakage into surrounding tissues, which can compromise efficacy and contribute to toxicity. Controlled release drug delivery systems such as in situ-forming hydrogels are promising vehicles for addressing these challenges by providing improved spatio-temporal control of locally administered immunotherapies with the goal of promoting systemic tumor-specific immune responses and abscopal effects. In this review we will discuss concepts, applications, and challenges in local delivery of immunotherapy using controlled release drug delivery systems with a focus on intratumorally injected hydrogel-based drug carriers.

Virtual Treatment Zone From Cone Beam CT Commonly Alters Treatment Plan and Identifies Tumor at Risk for Under-Treatment in US or US Fusion-Guided Microwave Ablation of Liver Tumors.

Tumor ablation is included in several major cancer therapy guidelines. One technical challenge of percutaneous ablation is targeting and verification of complete treatment, which is prone to operator variabilities and human imperfections and are directly related to successful outcomes, risk for residual unablated tumor and local progression. The use of "Prediction Ablation Volume Software" may help the operating Interventional Radiologist to better plan, deliver, and verify before the ablation, via virtual treatment zones fused to target tumor. Fused and superimposed images provide 3-dimensional information from different timepoints, just when that information is most useful. The aim of this study is to evaluate the technical success and efficacy of an ablation treatment flowchart provided by a cone beam computed tomography (CBCT) "Prediction Ablation Volume Software." This is a single-center retrospective study. From April 2021 to January 2022, 29 nonconsecutive evaluable patients with 32 lesions underwent liver ablation with Prediction Ablation Volume Software. Each patient was discussed in a multidisciplinary tumor board and underwent an enhanced computed tomography or magnetic resonance imaging approximately 1 month before the procedure, as well as ∼1 month after. Technical success was defined as treatment of the tumor according to the protocol, covered completely by the Prediction Ablation Volume. Technical efficacy was defined as assessment of complete ablation of the target tumor at imaging follow up (∼1 month). Technical success, technical efficacy, and procedural factors were studied. Technical success was achieved in 30 of 32 liver lesions (94%), measuring 20 mm mean maximum diameter. The antenna was repositioned in 16 of 30 (53%) evaluable target lesions. Residual tumor was detected at 1 month imaging follow up in only 4 of 30 (13%) of the treated lesion. Technical efficacy was of 87% in this retrospective description of our process. The implementation of a CBCT Prediction Ablation Volume Software and flowchart for the treatment of liver malignancies altered the procedure, and demonstrated high technical success and efficacy. Such tools are potentially useful for procedural prediction and verification of ablation.

Precision Imaging Guidance in the Era of Precision Oncology: An Update of Imaging Tools for Interventional Procedures.

Interventional oncology (IO) procedures have become extremely popular in interventional radiology (IR) and play an essential role in the diagnosis, treatment, and supportive care of oncologic patients through new and safe procedures. IR procedures can be divided into two main groups: vascular and non-vascular. Vascular approaches are mainly based on embolization and concomitant injection of chemotherapeutics directly into the tumor-feeding vessels. Percutaneous approaches are a type of non-vascular procedures and include percutaneous image-guided biopsies and different ablation techniques with radiofrequency, microwaves, cryoablation, and focused ultrasound. The use of these techniques requires precise imaging pretreatment planning and guidance that can be provided through different imaging techniques: ultrasound, computed tomography, cone-beam computed tomography, and magnetic resonance. These imaging modalities can be used alone or in combination, thanks to fusion imaging, to further improve the confidence of the operators and the efficacy and safety of the procedures. This article aims is to provide an overview of the available IO procedures based on clinical imaging guidance to develop a targeted and optimal approach to cancer patients.

Lifesaving embolization in a massive lumbar artery bleeding: Interventional radiology management.

Vertebral fractures are the most frequent fractures associated with osteoporosis. Thus far, there are no reported cases in literature analyzing intervertebral bleeding as a result of an osteoporotic vertebral fracture. The authors report a case of an 85-year-old woman in hemorrhagic shock for an unusual vertebral fracture causing a massive bleeding, which was contained by the vertebral ligament system inside the body of L4, treated with an endovascular approach. Since there are no guidelines for a treatment for the case mentioned above or similar, our aim is to describe a possible approach to a potentially life-threatening rare event.

Early detection of deep vein thrombosis in patients with coronavirus disease 2019: who to screen and who not to with Doppler ultrasound?

PURPOSE: Aim of the study is to evaluate the incidence of DVT in COVID-19 patients and its correlation with the severity of the disease and with clinical and laboratory findings. METHODS: 234 symptomatic patients with COVID-19, diagnosed according to the World Health Organization guidelines, were included in the study. The severity of the disease was classified as moderate, severe and critical. Doppler ultrasound (DUS) was performed in all patients. DUS findings, clinical, laboratory's and therapeutic variables were investigated by contingency tables, Pearson chi square test and by Student t test and Fisher's exact test. ROC curve analysis was applied to study significant continuous variables. RESULTS: Overall incidence of DVT was 10.7% (25/234): 1.6% (1/60) among moderate cases, 13.8% (24/174) in severely and critically ill patients. Prolonged bedrest and intensive care unit admission were significantly associated with the presence of DVT (19.7%). Fraction of inspired oxygen, P/F ratio, respiratory rate, heparin administration, D-dimer, IL-6, ferritin and CRP showed correlation with DVT. CONCLUSION: DUS may be considered a useful and valid tool for early identification of DVT. In less severely affected patients, DUS as screening of DVT might be unnecessary. High rate of DVT found in severe patients and its correlation with respiratory parameters and some significant laboratory findings suggests that these can be used as a screening tool for patients who should be getting DUS.

Bedside vascular access procedures for COVID-19 patients.

This report aims to illustrate how to perform a venous access to a COVID-19 patient at the bedside. The decision on the type of venous access, the selection of the material necessary to perform the procedure, and the preparation of the operators are described. The described approach can reduce costs, speed up execution times, and make the operator's work safer. Furthermore, these precautions may help control the spread of COVID-19 within the healthcare facility.

Image-guided percutaneous mechanical disc decompression for herniated discs: a technical note.

Interventional radiology plays a key role in the treatment of symptomatic herniations of intervertebral discs. Through image-guided techniques, it is possible to use minimally invasive procedures with a percutaneous approach that are usually proposed before classic surgery. Thanks to imaging guidance, it is possible to significantly increase accuracy and decrease complication rates. The pivotal principle of these mini-invasive techniques is to remove a small amount of volume of the nucleus of the intervertebral disc which results in a significant reduction in intradiscal pressure; allowing for a consequent reduction in compression of the nervous structures that generate spinal pain. However, it must be considered that this type of treatment is only addressed to contained disc herniations previously diagnosed with a suitable neuroimaging examination. There are different types of treatment using a variety of chemical, thermal or mechanical processes that result in partial removal of the nucleus pulposus. The purpose of this technical note is to illustrate mechanical disc decompression treatment via a percutaneous approach using the DISKOM device (DISKOM percutaneous discectomy probe, Biopsybell, Mirandola, Italy). Indications, complications and various methods of use are described in relation to the different levels of the spine to be treated.

Use of perfusional CBCT imaging for intraprocedural evaluation of endovascular treatment in patients with diabetic foot: a concept paper.

Diabetes mellitus (DM) is one of the most common metabolic diseases worldwide; its global burden has increased rapidly over the past decade, enough to be considered a public health emergency in many countries. Diabetic foot disease and, particularly diabetic foot ulceration, is the major complication of DM: through a skin damage of the foot, with a loss of epithelial tissue, it can deepen to muscles and bones and lead to the amputation of the lower limbs. Peripheral arterial disease (PAD) in patients with diabetes, manifests like a diffuse macroangiopathic multi-segmental involvement of the lower limb vessels, also connected to a damage of collateral circulation; it may also display characteristic microaneurysms and tortuosity in distal arteries. As validation method, Bold-MRI is used. The diabetic foot should be handled with a multidisciplinary team approach, as its management requires systemic and localized treatments, pain control, monitoring of cardiovascular risk factors and other comorbidities. CBCT is an emerging medical imaging technique with the original feature of divergent radiation, forming a cone, in contrast with the spiral slicing of conventional CT, and has become increasingly important in treatment planning and diagnosis: from small anatomical areas, such as implantology, to the world of interventional radiology, with a wide range of applications: as guidance for biopsies or ablation treatments. The aim of this project is to evaluate the usefulness of perfusion CBCT imaging, obtained during endovascular revascularization, for intraprocedural evaluation of endovascular treatment in patients with diabetic foot.

Interventional radiology management of high flow priapism: review of the literature.

INTRODUCTION: High-flow priapism is a persistent partial penile tumescence, related to high flow arterial blood into the corpora. In the treatment of high flow priapism, super-selective embolization is considered treatment of choice when conservative treatment fails as reported in the "EAU Guidelines on Priapism", but there are only few series reporting the outcome, the efficacy of different embolic materials and these studies are uncontrolled and relatively small. OBJECTIVES: The aim of this study is to review the literature to outline the state of the art of this interventional treatment and to analyse the outcome of the different embolic agents. METHODS: Through Medline database we searched all the English-language published articles related to priapism. Keywords were chosen according to MeSH terms. We selected case-series from 1990 to 2020 including at least five cases of high-flow priapism.The variables extracted from the selected articles were: number of patients, mean age, diagnostic imaging modality, mono or bilateral involvement of the arteries, embolization material, technical success, clinical success, complications, recurrence rate and type of reintervention, mean follow up, onset of erectile dysfunction. RESULTS: We analyzed 11 papers.A total of 117 patients, mean age of 30 years, were studied during a period of 8 to 72 months. Technical success average was 99%, varying from 93 to 100%. Clinical success average was 88%, varying from 56 to 100%. After two or more treatments, resolution of priapism was obtained in all patients. No major adverse events registered. Recurrence rate of 21%(25/117) was observed, and only 4 pts underwent surgery. A total of 17 pts (15%) developed erectile dysfunction (ED). CONCLUSION: Our data suggested comparable outcomes using different types of materials.In line with the last evidences we suggest that the choice of the embolic material should be selected basing on the expertise of the operator, the characteristic of the fistula and characteristic of the patients.

Percutaneous lung microwave ablation versus lung resection in high-risk patients. A monocentric experience.

BACKGROUND AND AIM OF WORK: Lung microwave ablation (MWA) is considered an alternative treatment in high-risk patients, not suitable for surgery. The aim of our study is to compare MWA and pulmonary lobectomy in high-risk, lung cancer patients. METHODS: This was a single-center, propensity score--weighted cohort study. All adult patients who underwent CT guided MWA for stage I NSCLC between June 2009-October 2014 were included in the study and were compared with a cohort of patients submitted to lung lobectomy in the same period of time. Outcomes were overall survival (OS) and disease-free survival (DFS). RESULTS: 32 patients underwent MWA, and 35 high-risk patients submitted to lung lobectomy in the same period were selected. Median follow-up time was 51.1 months (95% CI: 43.8-62.3). Overall survival was 43.8 (95% CI: 26.1-55) and 55.8 months (95% CI: 49.9-76.8) in the MWA group and Lobectomy group, respectively. Negative prognostic factors were MWA procedure (HR:2.25, 95% CI: 1.20-4.21, p= 0.0109) and nodule diameter (HR: 1.04, 95% CI: 1.01-1.07; p= 0.007) for OS, while MWA procedure (HR: 5.2; 95% CI: 2.1-12.8: p < 0.001), ECOG 3 (HR: 5.0; 95% CI: 1.6-15.6; p = 0.006) and nodule diameter (HR: 1.1; 95% CI: 1.0-1.1; p = 0.003) for DFS. CONCLUSIONS: Our study demonstrated a high percentage of local relapse in the MWA group but a comparable overall survival. Although lung lobectomy remains the gold standard treatment for stage I NSCLC, we can consider the MWA procedure as valid alternative local treatment in high-risk patients for stage I NSCLC.

Software-assisted US/MRI fusion-targeted biopsy for prostate cancer.

BACKGROUND: Prostate cancer is the first cancer diagnosis in men. European Association of Urology  (EAU) Guidelines for Prostate Cancer underline the importance of screening, performed through PSA testing on all men with more than 50 years of age and before on men with risk factors. The diagnosis is still histopathologic, and it is done on the basis of the findings on biopsy samples. MATERIALS AND METHODS: Fusion biopsy is a relatively new technique that allows the operator to perform the biopsies in office instead of the MRI gantry, without losing the detection capability of MRI. The  T2-wighted images obtained during a previous mpMRI are merged with the real-time ones of the TRUS. RESULTS: Fusion biopsy in comparison with the systematic standard biopsy has a better detection rate of clinically significant cancers and of any cancers. CONCLUSION: EAU 2020 guidelines still do offer a list of indications of when the biopsy should be performed, but it still appeared to be overperformed. The aim of our study is to underline how, in accordance with the recent literature result,  fusion biopsy has showed a better detection rate of any cancer and clinically significant disease with a reduced numbers of samplings, and no substantial difference between the multiple software.

Flow diverting devices in acute ruptured blood blister aneurysms: a three centric retrospective study.

BACKGROUND: Blood blister aneurysms (BBAs) are a rare tiny subset of intracranial aneurysms, located at the nonbranching site of an artery, representing a therapeutic challenge from both surgical and endovascular approach. Flow-diverting efficacy, by preserving flow through the parent artery, was approved for its use in unruptured cerebral aneurysms, but no consensus was reached on its use for BBAs ruptured in the acute setting. We report a multicenter experience of use of flow diversion in acute setting of ruptured BBA, to analyze the safety and efficacy of these devices. METHODS: We performed a retrospective study of 6 consecutive intracranial BBAs treated with flow diverter devices (FDD) between 2018 and 2020 at 3 italian institutions. Materials, therapy used, complications, clinical and radiographic outcomes were reviewed. RESULTS: We used different FDD, in all cases immediate change in contrast opacification at the end of the procedure was reported. Intraprocedural IIb/IIIa inhibitor agent was the major antiplatelet protocol administered. Any complications occurred. All patients showed complete BBA obliteration at 3 months follow-up. 5/6 patients achieved good clinical outcome (0-2 mRS) at 3 months, all of which were presented with low grade SAH (Hunt Hess I-III) and a lower Fisher grade. CONCLUSION: Our data support this endovascular technique as a safe and effective therapeutic modality for this pathology in the acute setting.

Efficacy, safety and usability of bronchial artery embolization using a new anti-reflux microcatheter in the management of haemoptysis.

PURPOSE: Haemoptysis (Hp) is a potentially life-threatening medical condition. We investigated the safety, efficacy and usability of bronchial artery embolization using a new anti-reflux microcatheter in patients with haemoptysis. MATERIALS AND METHODS: The study was held as a single-center retrospective study. Four patients underwent bronchial arterial embolization, using the new microcatheter. Then, we evalueted technical success, immediate clinical success, haemoptysis recurrance rate and safety in reducing reflux complications. Conclusion Bronchial artery embolization for hemoptysis with the new microcatheter is a safe and effective method with high technical and clinical success rates. Short and medium-term results are excellent.

Prostatic artery embolization in patients with benign prostatic hyperplasia: perfusion cone-beam CT to evaluate planning and treatment response.

This proof of concept is to evaluate the utility of perfusion cone-beam computed tomography (CT) in patients undergoing prostatic artery (PA) embolization (PAE) for benign prostatic hyperplasia (BPH) with moderate or severe-grade lower urinary tract symptoms (LUTS). PAE is a novel minimally invasive therapy and is both safe and effective procedure with low risks and high technical successes, making this procedure as the best alternative to surgery. A lot of technical changes would compromise clinical outcomes after procedure, including a variable prostate vascular anatomy, thin PA, and extensive atherosclerotic disease. The purpose of our study is to exploit the advantages of Perfusion Cone Beam Computed Tomography (CBCT) that could impact treatment and help interventional radiologists for treatment planning, diagnosis and for assessing the technical feasibility during PAE, mitigating the risk of nontarget embolization and suggesting clinical outcomes. Qualitative and quantitative clinical pre- and post-treatment values will be compared, to reach the best possible results.

Branch vessel occlusion in aneurysm treatment with flow diverter stent.

Flow diverter placement for treatment of intracranial aneurysms gained growing consensus in the past years. A major concern among professionals is the side branch coverage which leads in some cases to vessel occlusion. However, the lost vessel patency only infrequently is accompanied by a new onset of neurological deficits secondary to ischaemic lesions. A retrospective analysis of all patients treated with flow diversion at our hospital was aimed to better understand this phenomenon in order to formulate a hypothesis about the causes. We concluded that vessel occlusion occurs due to a reduced blood pressure gradient in those vessels with a strong collateral or anastomotic vascularization that refurnishes the same distal vascular territories. Indeed, we detected no new brain infarction since blood flow was always guaranteed.