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The aim of this study was to validate a previously developed deep learning model in 5 independent clinical trials. The predictive performance of this model was compared with the international prognostic index (IPI) and 2 models incorporating radiomic PET/CT features (clinical PET and PET models). Methods: In total, 1,132 diffuse large B-cell lymphoma patients were included: 296 for training and 836 for external validation. The primary outcome was 2-y time to progression. The deep learning model was trained on maximum-intensity projections from PET/CT scans. The clinical PET model included metabolic tumor volume, maximum distance from the bulkiest lesion to another lesion, SUV peak , age, and performance status. The PET model included metabolic tumor volume, maximum distance from the bulkiest lesion to another lesion, and SUV peak Model performance was assessed using the area under the curve (AUC) and Kaplan-Meier curves. Results: The IPI yielded an AUC of 0.60 on all external data. The deep learning model yielded a significantly higher AUC of 0.66 ( P < 0.01). For each individual clinical trial, the model was consistently better than IPI. Radiomic model AUCs remained higher for all clinical trials. The deep learning and clinical PET models showed equivalent performance (AUC, 0.69; P > 0.05). The PET model yielded the highest AUC of all models (AUC, 0.71; P < 0.05). Conclusion: The deep learning model predicted outcome in all trials with a higher performance than IPI and better survival curve separation. This model can predict treatment outcome in diffuse large B-cell lymphoma without tumor delineation but at the cost of a lower prognostic performance than with radiomics., (© 2024 by the Society of Nuclear Medicine and Molecular Imaging.)

Objectives: To investigate the prognostic value of clinical, volumetric, and radiomics-based textural parameters in baseline [18F]FDG-PET/CT scans of diffuse large B-cell lymphoma (DLBCL) patients., Methods: We retrospectively investigated baseline PET/CT scans and collected clinical data of fifty DLBCL patients. PET images were segmented semiautomatically to determine metabolic tumor volume (MTV), then the largest segmented lymphoma volume of interest (VOI) was used to extract first-, second-, and high-order textural features. A novel value, MTVrate was introduced as the quotient of the largest lesion's volume and total body MTV. Receiver operating characteristics (ROC) analyses were performed and 24-months progression-free survival (PFS) of low- and high-risk cohorts were compared by log-rank analyses. A machine learning algorithm was used to build a prognostic model from the available clinical, volumetric, and textural data based on logistic regression., Results: The area-under-the-curve (AUC) on ROC analysis was the highest of MTVrate at 0.74, followed by lactate-dehydrogenase, MTV, and skewness, with AUCs of 0.68, 0.63, and 0.55, respectively which parameters were also able to differentiate the PFS. A combined survival analysis including MTV and MTVrate identified a subgroup with particularly low PFS at 38%. In the machine learning-based model had an AUC of 0.83 and the highest relative importance was attributed to three textural features and both MTV and MTVrate as important predictors of PFS., Conclusion: Individual evaluation of different biomarkers yielded only limited prognostic data, whereas a machine learning-based combined analysis had higher effectivity. MTVrate had the highest prognostic ability on individual analysis and, combined with MTV, it identified a patient group with particularly poor prognosis., (Copyright © 2024 The Author(s). Published by Wolters Kluwer Health, Inc.)

Abstract: A 76-year-old man with hepatocellular carcinoma was referred for liver radioembolization. Given a prior left hemihepatectomy, it was clinically important to consider potentially irradiated healthy liver at planning. Thus, at the SPECT/CT imaging of the scout dose 166 Ho-microparticles before injected superselectively in the right hepatic artery, 99m Tc-mebrofenin was injected intravenously, and functional volumetry SPECT was performed simultaneously. Based on the 2 image sets, the nonirradiated healthy liver was calculated as 1589 mL (functional liver reserve of 85.5% on 99m Tc-mebrofenin SPECT). Posttreatment dosimetry calculations showed optimal normal tissue and tumor absorbed doses, and the patient is clinically well after 3 months., Competing Interests: Conflicts of interest and sources of funding: none declared., (Copyright © 2023 The Author(s). Published by Wolters Kluwer Health, Inc.)

The staff of the Radiation Protection Service of a European clinical center measured the radiation dose by type-tested thermoluminescent dosemeter systems to which the medical staff was exposed, to assess the effectiveness of current procedures and equipment for optimalisation prompted by the requirements EU Basic Safety Standard 2013. There were three participating sites, the Site 1 was an external hospital, whereas Sites 2 and 3 are part of the same clinical center, who provided data regarding their personnel, from technologists, nurses and medical doctors. In this preliminary study, only a low number of cases were available and used to establish a new, more realistic yearly dose constraint, namely 6 (from two) mSv for whole-body effective dose, 15 (from two) mSv for eye lens dose and 300 (from 50) mSv for extremity dose. Furthermore, the state of safety culture and protection equipment was assessed. Collection of the sufficient amount of data for statistical evaluation is ongoing., (© The Author(s) 2023. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.)

Objective: 2-[ 18 F]fluoro-2-deoxy- d -glucose PET/computed tomography ([ 18 F]FDG-PET/CT) is a widely used imaging method in the management of diffuse large B-cell lymphomas (DLBCL). Our aim was to investigate the prognostic performance of different PET biomarkers in a multicenter setting., Methods: We investigated baseline volumetric values [metabolic tumor volume (MTV) and total lesion glycolysis (TLG), also normalized for body weight] segmented with three different methods [>SUV4 (glob4); 41% isocontour (41pc), and a gradient-based lesion growing algorithm (grad)] and interim parameters [Deauville score, maximal standardized uptake value (ΔSUVmax), modified qPET, and ratio PET (rPET)] alongside clinical parameters (stage, revised International Prognostic Index), using 24-month progression-free survival as the clinical endpoint. Receiver operating characteristics analyses were performed to define optimal cutoff points for the continuous PET parameters., Results: A total of 107 diffuse large B-cell lymphoma patients were included (54 women; mean age: 53.7 years). MTV and TLG calculations showed good correlation among glob4, 41pc, and grad methods; however, optimal cutoff points were markedly different.Significantly different PFS was observed between low- and high-risk groups according to baseline MTV, body weight-adjusted (bwa) MTV, TLG, bwaTLG, as well as interim parameters Deauville score, ΔSUVmax, mqPET, and rPET. Univariate Cox regression analyses showed hazard ratios (HRs) lowest for bwaMTVglob4 (HR = 2.3) and highest for rPET (HR = 9.09). In a multivariate Cox-regression model, rPET was shown to be an independent predictor of PFS ( P  = 0.041; HR = 9.15). Combined analysis showed that ΔSUVmax positive patients with high MTV formed a group with distinctly poor PFS (35.3%)., Conclusion: Baseline MTV and TLG values and optimal cutoff points achieved with different segmentation methods varied markedly and showed a limited prognostic impact. Interim PET/CT parameters provided more accurate prognostic information with semiquantitative 'Deauville-like' parameters performing best in the present study., (Copyright © 2023 The Author(s). Published by Wolters Kluwer Health, Inc.)

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Cardiac amyloidosis is an infiltrative disease primarily caused by extracellular tissue deposition of amyloid fibrils in the myocardial interstitium. The aim of the present review was to summarize findings regarding changes in myocardial mechanics, valvular abnormalities, and vascular remodeling detected in patients with cardiac amyloidosis. [ABSTRACT FROM AUTHOR]

According to current guidelines, only clinical surveillance is recommended for patients with moderate aortic valve stenosis (AS), while aortic valve replacement may be considered in patients undergoing surgery for other indications. Recent studies have shown that moderate AS is associated with a high risk of adverse cardiovascular events, including death, especially in patients with left ventricular dysfunction. In this context, multimodality imaging can help to improve the accuracy of moderate AS diagnosis and to assess left ventricular remodeling response. This review discusses the natural history of this valve disease and the role of multimodality imaging in the diagnostic process, summarizes current evidence on the medical and non-medical management, and highlights ongoing trials on valve replacement. [ABSTRACT FROM AUTHOR]

Cardiac amyloidosis (CA) is an underdiagnosed condition caused by the deposition of misfolded proteins, namely immunoglobulin light chains and transthyretin, in the extracellular spaces of the heart. Any cardiovascular structure can be affected by amyloid infiltration, including the valves. Amyloid accumulation within the cardiac valves may lead to their structural and functional impairment, with a profound impact on patients' prognosis and quality of life. The most common forms of valvular disease in CA are aortic stenosis (AS), mitral regurgitation (MR), and tricuspid regurgitation (TR). CA and AS share similar risk factors, disease mechanisms, and remodeling patterns, which make their diagnosis particularly challenging. Patients with both CA and AS experience worse outcomes than CA or AS alone, and transcatheter aortic valve replacement may represent a useful therapeutic strategy in this population. Data on MR and TR are quite limited and mainly coming from case reports or small series. This review paper will summarize our current understanding on the epidemiology, disease mechanisms, echocardiographic features, clinical implications, and therapeutic options of AS, MR, and TR in patients with CA. [ABSTRACT FROM AUTHOR]

Cardiac amyloidosis (CA) occurs when the insoluble fibrils formed by misfolded precursor proteins deposit in cardiac tissues. The early clinical manifestations of CA are not evident, but it is easy to progress to refractory heart failure with an inferior prognosis. Echocardiography is the most commonly adopted non-invasive modality of imaging to visualize cardiac structures and functions, and the preferred modality in the evaluation of patients with cardiac symptoms and suspected CA, which plays a vital role in the diagnosis, prognosis, and long-term management of CA. The present review summarizes the echocardiographic manifestations of CA, new echocardiographic techniques, and the application of multi-parametric echocardiographic models in CA diagnosis. [ABSTRACT FROM AUTHOR]

Background: Technetium-99 m 3,3-diphosphono-1,2-propanodicarboxylic acid (DPD) and technetium-99 m sodium pyrophosphate (PYP) are the two most commonly used radiotracers for cardiac amyloidosis (CA), but no studies have directly compared them. Therefore, in this study, we directly compared the diagnostic and clinical utility of DPD and PYP scintigraphy in patients with CA. Methods: Ten patients with CA were enrolled. Eight clinical variables and 12 scintigraphic parameters were used. Clinical variables were age, sex, estimated glomerular filtration rate (eGFR), N-terminal pro brain natriuretic peptide (NT-proBNP), and the results of electromyography (EMG), a sensory test, electrocardiogram, and echocardiography (EchoCG). Four heart retention ratios (heart/whole-body profile, heart/pelvis, heart/skull, and heart/contralateral lung) were calculated from the DPD and PYP scans and two visual scoring systems (Perugini and Dorbala systems) were used. Comparative analyses were performed between radiotracers and between visual scoring systems using clinical variables and scintigraphic parameters. Results: Twenty DPD parameters and nine PYP parameters had significant associations with age, eGFR, NT-proBNP, EchoCG, and EMG. DPD parameters had more frequent significant associations with clinical variables than PYP parameters. Compared to visual scores in the DPD scan, the proportion of patients with higher visual scores in the PYP scan was relatively greater than those with lower visual scores, and there were more patients with a visual score of 2 or higher in PYP scans than DPD scans. Conclusions: DPD scintigraphy may reflect the disease severity of CA better than PYP scintigraphy, whereas PYP scintigraphy may be a more sensitive imaging modality for identifying CA involvement. [ABSTRACT FROM AUTHOR]

The purpose of this study was to examine how the flipped learning readiness, engagement, autonomous learning, and computing achievements of university students in an online flipped classroom differ according to gender and feedback groups (verbal, written, and grade reporting) before and after a computing course. An 8‐week application was conducted with 104 university students enrolled Computing course at a state university, İstanbul, Turkey. Students were randomly assigned to three different feedback groups. An experimental design was used in this study and quantitative data was collected. Students did homework and written/verbal or grade feedback was given to students through Moodle. A flipped learning readiness scale, computing achievement test, online student engagement scale, and autonomous learning scale were given to participants as pretests and posttests. The results showed that computing academic achievement, flipped learning readiness, and engagement variables increased significantly. There were differences in online engagement regarding gender but no difference between feedback types. The research includes suggestions for future studies. [ABSTRACT FROM AUTHOR]

Aims Aortic stenosis (AS) and cardiac amyloidosis (CA) frequently coexist but the diagnosis of CA in AS patients remains a diagnostic challenge. We aim to evaluate the echocardiographic parameters that may aid in the detection of the presence of CA in AS patients. Method and results We performed a systematic literature search of electronic databases for peer-reviewed articles from inception until 10 January 2022. Of the 1449 patients included, 160 patients had both AS–CA whereas the remaining 1289 patients had AS-only. The result of our meta-analyses showed that interventricular septal thickness [standardized mean difference (SMD): 0.74, 95% CI: 0.36–1.12, P  = 0.0001), relative wall thickness (SMD: 0.74, 95% CI: 0.17–1.30, P  < 0.0001), posterior wall thickness (SMD: 0.74, 95% CI 0.51 to 0.97, P  = 0.0011), LV mass index (SMD: 1.62, 95% CI: 0.63–2.62, P  = 0.0014), E/A ratio (SMD: 4.18, 95% CI: 1.91–6.46, P  = 0.0003), and LA dimension (SMD: 0.73, 95% CI: 0.43–1.02, P  < 0.0001)] were found to be significantly higher in patients with AS–CA as compared with AS-only patients. In contrast, myocardial contraction fraction (SMD: −2.88, 95% CI: −5.70 to −0.06, P  = 0.045), average mitral annular S′ (SMD: −1.14, 95% CI: −1.86 to −0.43, P  = 0.0017), tricuspid annular plane systolic excursion (SMD: −0.36, 95% CI: −0.62 to −0.09, P  = 0.0081), and tricuspid annular S′ (SMD: −0.77, 95% CI: −1.13 to −0.42, P  < 0.0001) were found to be significantly lower in AS–CA patients. Conclusion Parameters based on echocardiography showed great promise in detecting CA in patients with AS. Further studies should explore the optimal cut-offs for these echocardiographic variables for better diagnostic accuracy. [ABSTRACT FROM AUTHOR]