1,720,980 research outputs found
Radiomics and machine learning applications in rectal cancer: Current update and future perspectives
Full text linkThe high incidence of rectal cancer in both sexes makes it one of the most common tumors, with significant morbidity and mortality rates. To define the best treatment option and optimize patient outcome, several rectal cancer biological variables must be evaluated. Currently, medical imaging plays a crucial role in the characterization of this disease, and it often requires a multimodal approach. Magnetic resonance imaging is the first-choice imaging modality for local staging and restaging and can be used to detect high-risk prognostic factors. Computed tomography is widely adopted for the detection of distant metastases. However, conventional imaging has recognized limitations, and many rectal cancer characteristics remain assessable only after surgery and histopathology evaluation. There is a growing interest in artificial intelligence applications in medicine, and imaging is by no means an exception. The introduction of radiomics, which allows the extraction of quantitative features that reflect tumor heterogeneity, allows the mining of data in medical images and paved the way for the identification of potential new imaging biomarkers. To manage such a huge amount of data, the use of machine learning algorithms has been proposed. Indeed, without prior explicit programming, they can be employed to build prediction models to support clinical decision making. In this review, current applications and future perspectives of artificial intelligence in medical imaging of rectal cancer are presented, with an imaging modality-based approach and a keen eye on unsolved issues. The results are promising, but the road ahead for translation in clinical practice is rather long
A rare case of congenital aneurysm of the portal system at level of spleno-porto-mesenteric confluence complicated by massive thrombosis
Full text linkPortal venous aneurysm is a rare and potential dangerous vascular pathology, which can result in thrombosis or rupture. It may be congenital or acquired. Acquired form can be related mainly to portal hypertension, chronic hepatic disease, and trauma. We present a peculiar case of a congenital aneurysm involving the hepatic portal system in nearly all its extra-hepatic components: the main portal trunk, the spleno-porto-mesenteric confluence and the distal segment of splenic, superior, and inferior mesenteric veins, in a 20-year-old male patient. The aneurysm was complicated by massive thrombosis in absence of further predisposing factors
Radiomics in Cross-Sectional Adrenal Imaging: A Systematic Review and Quality Assessment Study
No full textIn this study, we aimed to systematically review the current literature on radiomics applied to cross-sectional adrenal imaging and assess its methodological quality. Scopus, PubMed and Web of Science were searched to identify original research articles investigating radiomics applications on cross-sectional adrenal imaging (search end date February 2021). For qualitative synthesis, details regarding study design, aim, sample size and imaging modality were recorded as well as those regarding the radiomics pipeline (e.g., segmentation and feature extraction strategy). The methodological quality of each study was evaluated using the radiomics quality score (RQS). After duplicate removal and selection criteria application, 25 full-text articles were included and evaluated. All were retrospective studies, mostly based on CT images (17/25, 68%), with manual (19/25, 76%) and two-dimensional segmentation (13/25, 52%) being preferred. Machine learning was paired to radiomics in about half of the studies (12/25, 48%). The median total and percentage RQS scores were 2 (interquartile range, IQR = −5–8) and 6% (IQR = 0–22%), respectively. The highest and lowest scores registered were 12/36 (33%) and −5/36 (0%). The most critical issues were the absence of proper feature selection, the lack of appropriate model validation and poor data openness. The methodological quality of radiomics studies on adrenal cross-sectional imaging is heterogeneous and lower than desirable. Efforts toward building higher quality evidence are essential to facilitate the future translation into clinical practice
Diagnostic Imaging of Patients with Pancreato-Biliary Diseases: Comparison between Ultrasound, Computed Tomography and Magnetic Resonance
No full textColorectal cancer: Parametric evaluation of morphological, functional and molecular tomographic imaging
Full text linkColorectal cancer (CRC) represents one of the leading causes of tumor-related deaths worldwide. Among the various tools at physicians' disposal for the diagnostic management of the disease, tomographic imaging (e.g.,CT,MRI,and hybrid PET imaging) is considered essential.The qualitative and subjective evaluation of tomographic images is the main approach used to obtain valuable clinical information,although this strategy suffers from both intrinsic and operator-dependent limitations.More recently,advanced imaging techniques have been developed with the aim of overcoming these issues.Such techniques,such as diffusion-weighted MRI and perfusion imaging,were designed for the "in vivo"evaluation of specific biological tissue features in order to describe them in terms of quantitative parameters,which could answer questions difficult to address with conventional imaging alone(e.g., questions related to tissue characterization and prognosis).Furthermore,it has been observed that a large amount of numerical and statistical information is buried inside tomographic images,resulting in their invisibility during conventional assessment.This information can be extracted and represented in terms of quantitative parameters through different processes(e.g., texture analysis).Numerous researchers have focused their work on the significance of these quantitative imaging parameters for the management of CRC patients.In this review,we aimed to focus on evidence reported in the academic literature regarding the application of parametric imaging to the diagnosis, staging and prognosis of CRC while discussing future perspectives and present limitations.While the transition from purely anatomical to quantitative tomographic imaging appears achievable for CRC diagnostics,some essential milestones, such as scanning and analysis standardization and the definition of robust cut-off values,must be achieved before quantitative tomographic imaging can be incorporated into daily clinical practice
Diagnostic Imaging of Patients with Pancreato-Biliary Disease: Comparison between Ultrasound, Computed Tomography and Magnetic Resonance
No full textGoing Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Precocious ischemia preceding bilateral adrenal hemorrhage: A case report
Full text linkWe present a case of a middle-age male who presented in emergency room with nonspecific abdominal pain. A contrast-enhanced computer tomography (ceCT) scan showed a reduced perfusion of both adrenal glands. The clinical examinations and the laboratory tests were negative for an adrenal pathological process. To reassess the adrenal ischemia, a second ceCT scan was performed 5 days later showing an acute bilateral adrenal hemorrhage. These findings demonstrated that the previous adrenal hypoperfusion represented the prodromal manifestation of a hemorrhagic intraglandular process. This case suggests that adrenal hypoperfusion detected on tomographic imaging dictates a prompt clinical management finalized to strictly monitor the potential evolution towards a more aggressive pathological condition and confirms the pivotal role of imaging in the diagnosis of such uncommon disorder
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