890 research outputs found

    Resectable and borderline resectable pancreatic ductal adenocarcinoma: Role of the radiologist and oncologist in the era of precision medicine

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    The incidence and mortality of pancreatic ductal adenocarcinoma are growing over time. The management of patients with pancreatic ductal adenocarcinoma involves a multidisciplinary team, ideally involving experts from surgery, diagnostic imaging, interventional endoscopy, medical oncology, radiation oncology, pathology, geriatric medicine, and palliative care. An adequate staging of pancreatic ductal adenocarcinoma and re-assessment of the tumor after neoadjuvant therapy allows the multidisciplinary team to choose the most appropriate treatment for the patient. This review article discusses advancement in the molecular basis of pancreatic ductal adenocarcinoma, diagnostic tools available for staging and tumor response assessment, and management of resectable or borderline resectable pancreatic cancer

    CULTURAL HERITAGE DIGITAL PRESERVATION THROUGH AI-DRIVEN ROBOTICS

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    This paper introduces a novel methodology developed for creating 3D models of archaeological artifacts that reduces the time and effort required by operators. The approach uses a simple vision system mounted on a robotic arm that follows a predetermined path around the object to be reconstructed. The robotic system captures different viewing angles of the object and assigns 3D coordinates corresponding to the robot's pose, allowing it to adjust the trajectory to accommodate objects of various shapes and sizes. The angular displacement between consecutive acquisitions can also be fine-tuned based on the desired final resolution. This flexible approach is suitable for different object sizes, textures, and levels of detail, making it ideal for both large volumes with low detail and small volumes with high detail. The recorded images and assigned coordinates are fed into a constrained implementation of the structure-from-motion (SfM) algorithm, which uses the scale-invariant features transform (SIFT) method to detect key points in each image. By utilising a priori knowledge of the coordinates and SIFT algorithm, low processing time can be ensured while maintaining high accuracy in the final reconstruction. The use of a robotic system to acquire images at a pre-defined pace ensures high repeatability and consistency across different 3D reconstructions, eliminating operator errors in the workflow. This approach not only allows for comparisons between similar objects but also provides the ability to track structural changes of the same object over time. Overall, the proposed methodology provides a significant improvement over current photogrammetry techniques by reducing the time and effort required to create 3D models while maintaining a high level of accuracy and repeatability

    Capacitance study of thin film SnO2:F/p-type a-Si:H heterojunctions

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    Abstract We characterized SnO 2 :F/p-type a-Si:H heterojunctions by current-voltage (I-V) and capacitance-voltage (C-V) measurements at room temperature to determine the junction parameters. Samples with circular geometry and different diameters were characterized. The current scales with the junction area, and the current density J as a function of the voltage V is a slightly asymmetric curve with a super-linear behaviour (cubic law) for high voltages. Using a transmission line model valid for devices with circular geometry, we studied the effects of the SnO 2 :F resistivity on the measured capacitance when the SnO2:F layer works as an electrical contact. The measured C-V curve allows us to determine junction parameters as doping of p-type a-Si:H, built-in potential and depletion width for the heterojunction with the smallest diameters, demonstrating that for these samples the TCO effects can be neglected. We compared theoretical and measured data to explain qualitatively the transport mechanism in this heterojunction

    Sperimentazione di una procedura per la creazione di un atlante digitale per la documentazione dei soffitti lignei dipinti di Sicilia

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    the naves of churches and the halls of noble palaces. The paintings that decorate these ceilings are precious evidence of the wide cultural connections that linked Sicily to Europe and to the Mediterranean area. The paper reports the results of research aiming at the development of a workflow for the creation of a digital atlas of these ceilings. Digital representation overcomes one of the main obstacles to the study, the preservation and the dissemination of these works of art, i.e. the traditional dichotomy between photographic images and drawings. The chosen case study is the ceiling that covers the main hall of the Steri in Palermo, a 14th-century palace that today hosts the offices of the local university’s rector. The first step of the study, dedicated to laser scanning and SfM photogrammetric surveying, produced a textured mesh model of the ceiling. The following step was addressed to the development of a web-based application that allows a wide range of users to visualize the 3D model of the ceiling and the orthophotos of the paintings; in order to make 3D visualization easier, the 3D textured model was subdivided into base units; the pages dedicated to the orthophotos are linked to an editable database that stores information data

    The Neoplastic Side of the Abdominal Wall: A Comprehensive Pictorial Essay of Benign and Malignant Neoplasms

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    Abdominal wall neoplasms are usually benign and, in the majority of these cases, no further work-up or treatment is indicated. The percentage of malignant abdominal neoplasms, however, is not negligible. Radiologists play a pivotal role in identifying imaging features that should favor malignancy, including larger lesion size, edema, neurovascular involvement, and peripheral or inhomogeneous dynamic enhancement, thus indicating to the clinician the need for further work-up. Histopathology is the reference standard for the characterization of abdominal wall neoplasms. In patients undergoing surgery, radiological assessment is needed to guide the surgeon by providing a comprehensive anatomic guide of the tumor extension. We present a pictorial review of benign and malignant abdominal wall neoplasms that can be encountered on radiological examinations, with a main focus on CT and MRI features that help in narrowing the differential diagnosis

    The Benign Side of the Abdominal Wall: A Pictorial Review of Non-Neoplastic Diseases

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    The abdominal wall is the location of a wide spectrum of pathological conditions, from benign to malignant ones. Imaging is often recommended for the evaluation of known palpable abdominal masses. However, abdominal wall pathologies are often incidentally discovered and represent a clinical and diagnostic challenge. Knowledge of the possible etiologies and complications, combined with clinical history and laboratory findings, is crucial for the correct management of these conditions. Specific imaging clues can help the radiologist narrow the differential diagnosis and distinguish between malignant and benign processes. In this pictorial review, we will focus on the non-neoplastic benign masses and processes that can be encountered on the abdominal wall on cross-sectional imaging, with a particular focus on their management. Distinctive sonographic imaging clues, compared with computed tomography (CT) and magnetic resonance (MR) findings will be highlighted, together with clinical and practical tips for reaching the diagnosis and guiding patient management, to provide a complete diagnostic guide for the radiologist

    Imaging-guided interventions modulating portal venous flow: Evidence and controversies

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    Portal hypertension is defined by an increase in the portosystemic venous gradient. In most cases, increased resistance to portal blood flow is the initial cause of elevated portal pressure. More than 90% of cases of portal hypertension are estimated to be due to advanced chronic liver disease or cirrhosis. Transjugular intrahepatic portosystemic shunts, a non-pharmacological treatment for portal hypertension, involve the placement of a stent between the portal vein and the hepatic vein or inferior vena cava which helps bypass hepatic resistance. Portal hypertension may also be a result of extrahepatic portal vein thrombosis or compression. In these cases, percutaneous portal vein recanalisation restores portal trunk patency, thus preventing portal hypertension-related complications. Any portal blood flow impairment leads to progressive parenchymal atrophy and triggers hepatic regeneration in preserved areas. This provides the rationale for using portal vein embolisation to modulate hepatic volume in preparation for extended hepatic resection. The aim of this paper is to provide a comprehensive evidence-based review of the rationale for, and outcomes associated with, the main imaging-guided interventions targeting the portal vein, as well as to discuss the main controversies around such approaches. (c) 2022 The Authors. Published by Elsevier B.V. on behalf of European Association for the Study of the Liver (EASL). This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/ licenses/by-nc-nd/4.0/)

    Innovative techniques for survey and communication of cultural heritage

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    This paper deals with the survey and communications of Cultural Heritage through the development of innovative methodologies. The case of study is the polychrome wooden ceiling in the \u201cMagna\u201d Hall of \u201cPalazzo Steri\u201d. The \u201cSteri\u201d, built in the XIVth century by the noble family Chiaromonte, is at the present the headquarter of the Rector\u2019s Office of Palermo University. A 3D model of the wooden ceiling has initially been carried out with laser-scanning and digital photogrammetric techniques; successively a multimodal interactive guide has been realized. The guide is integrated to the 3D model, so that visitors can navigate the virtual representation of the ancient wood ceiling and achieve, interacting vocally, relevant meta information about history and sense of painted scenes

    Spectrum of liver lesions hyperintense on hepatobiliary phase: an approach by clinical setting

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    Hepatobiliary MRI contrast agents are increasingly being used for liver imaging. In clinical practice, most focal liver lesions do not uptake hepatobiliary contrast agents. Less commonly, hepatic lesions may show variable signal characteristics on hepatobiliary phase. This pictorial essay reviews a broad spectrum of benign and malignant focal hepatic observations that may show hyperintensity on hepatobiliary phase in various clinical settings. In non-cirrhotic patients, focal hepatic observations that show hyperintensity in the hepatobiliary phase are usually benign and typically include focal nodular hyperplasia. In patients with primary or secondary vascular disorders, focal nodular hyperplasia-like lesions arise as a local hyperplastic response to vascular alterations and tend to be iso- or hyperintense in the hepatobiliary phase. In oncologic patients, metastases and cholangiocarcinoma are hypointense lesions in the hepatobiliary phase; however, occasionally they may show a diffuse, central and inhomogeneous hepatobiliary paradoxical uptake with peripheral rim hypointensity. Post-chemotherapy focal nodular hyperplasia-like lesions may be tricky, and their typical hyperintense rim in the hepatobiliary phase is very helpful for the differential diagnosis with metastases. In cirrhotic patients, hepatocellular carcinoma may occasionally appear hyperintense on hepatobiliary phase

    Chimeric Antigen Receptor T-cell Therapy in Hematologic Malignancies and Patient-reported Outcomes: A Scoping Review

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    The inclusion of patient-reported outcome (PRO) measures in chimeric antigen receptor (CAR) T-cell therapy research is critical for understanding the impact of this novel approach from a unique patient standpoint. We performed a scoping review to map the available literature on the use of PRO measures in CAR T-cell therapy studies of patients with hematologic malignancies published between January 2015 and July 2022. Fourteen studies were identified, of which 7 (50%) were investigational early-phase trials, 6 (42.9%) were observational studies, and 1 (7.1%) was a pilot study. The EQ-5D and the PROMIS-29 were the 2 most frequently used PRO measures, being included in 6 (42.9%) and 5 (35.7%) studies, respectively. Despite differences in study designs, there seems to be evidence of improvements over time since CAR T-cell infusion in important domains such as physical functioning and fatigue, at least in patients who respond to therapy. Overall, the studies identified in our review have shown the added value of PRO assessment in CAR T-cell therapy research by providing novel information that complements the knowledge on safety and efficacy. However, there are several questions which remain to be answered in future research. For example, limited evidence exists regarding patient experience during important phases of the disease trajectory as only 4 (28.6%) and 5 (35.7%) studies provided information on PROs during the first 2 weeks from CAR T-cell infusion and after the first year, respectively. Time is ripe for a more systematic implementation of high-quality PRO assessment in future clinical trials and in real-life settings of patients treated with CAR T-cell therapy
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