1,262 results match your criteria estimating volumes

Deep neural network ensemble for on-the-fly quality control-driven segmentation of cardiac MRI T1 mapping.

Med Image Anal 2021 Mar 11;71:102029. Epub 2021 Mar 11.

Oxford University Centre for Clinical Magnetic Resonance Research (OCMR), Level 0, John Radcliffe Hospital, Headington, Oxford OX3 9DU, United Kingdom.

Recent developments in artificial intelligence have generated increasing interest to deploy automated image analysis for diagnostic imaging and large-scale clinical applications. However, inaccuracy from automated methods could lead to incorrect conclusions, diagnoses or even harm to patients. Manual inspection for potential inaccuracies is labor-intensive and time-consuming, hampering progress towards fast and accurate clinical reporting in high volumes. Read More

View Article and Full-Text PDF

Tissue dose estimation after extravasation of Lu-DOTATATE.

EJNMMI Phys 2021 Mar 31;8(1):33. Epub 2021 Mar 31.

Service de Physique Médicale et Radioprotection, Hospices Civils de Lyon, Lyon, France.

Background: Extravasation of radiopharmaceuticals used for vectorized internal radiotherapy can lead to severe tissue damage (van der Pol et al., Eur J Nucl Med Mol Imaging 44:1234-1243, 2017). Clinical management of these extravasations requires the preliminary estimation of the dose distribution in the extravasation area. Read More

View Article and Full-Text PDF

Tumor attention networks: Better feature selection, better tumor segmentation.

Neural Netw 2021 Mar 13;140:203-222. Epub 2021 Mar 13.

School of Data and Computer Science, Shandong Women's University, Jinan 250014, China. Electronic address:

Compared with the traditional analysis of computed tomography scans, automatic liver tumor segmentation can supply precise tumor volumes and reduce the inter-observer variability in estimating the tumor size and the tumor burden, which could further assist physicians to make better therapeutic choices for hepatic diseases and monitoring treatment. Among current mainstream segmentation approaches, multi-layer and multi-kernel convolutional neural networks (CNNs) have attracted much attention in diverse biomedical/medical image segmentation tasks with remarkable performance. However, an arbitrary stacking of feature maps makes CNNs quite inconsistent in imitating the cognition and the visual attention of human beings for a specific visual task. Read More

View Article and Full-Text PDF

Volume and accumulation patterns of physical activity and sedentary time: longitudinal changes and tracking from early to late childhood.

Int J Behav Nutr Phys Act 2021 Mar 17;18(1):39. Epub 2021 Mar 17.

Institute for Physical Activity and Nutrition (IPAN), School of Exercise and Nutrition Sciences, Deakin University, Geelong, Australia.

Background: Physical activity (PA) decreases and sedentary time (SED) increases across childhood, with both behaviours tracking. However, no studies have examined how accumulation patterns of PA and SED (i.e. Read More

View Article and Full-Text PDF

Deep Learning-Based Computed Tomography Perfusion Mapping (DL-CTPM) for Pulmonary CT-to-Perfusion Translation.

Int J Radiat Oncol Biol Phys 2021 Mar 6. Epub 2021 Mar 6.

Department of Health Technology and Informatics, The Hong Kong Polytechnic University, Hong Kong. Electronic address:

Purpose: To develop a deep learning-based computed tomography (CT) perfusion mapping (DL-CTPM) method that synthesizes lung perfusion images from CT images.

Methods And Materials: This paper presents a retrospective analysis of the pulmonary technetium-99m-labeled macro-aggregated albumin (MAA) single-photon emission computed tomography (SPECT)/CT scans obtained from 73 patients at xx Hospital in Hong Kong in 2019. The left and right lung scans were separated to double the size of the dataset to 146. Read More

View Article and Full-Text PDF

Accuracy of Clarius, Handheld Wireless Point-of-Care Ultrasound, in Evaluating Prostate Morphology and Volume Compared to Radical Prostatectomy Specimen Weight: Is There a Difference between Transabdominal Transrectal Approach?

J Endourol 2021 Mar 26. Epub 2021 Mar 26.

Division of Urology, Department of Surgery, University of Montreal Hospital Center, Montreal, Canada.

Prostate size estimation is a valuable clinical measure widely utilized in urology. This study evaluated the accuracy of preoperative transabdominal ultrasound (TAUS) compared to radical prostatectomy specimens and transrectal ultrasound (TRUS) in estimating prostate volume and identifying presence of median lobe, across different size groups, using the standard ellipsoid formula. The effect of median lobe on accuracy was also assessed. Read More

View Article and Full-Text PDF

Estimating the Impact of Economic Fluctuations on Unemployment in Russian Regions Based on the Okun Model.

Stud Russ Econ Dev 2021 19;32(1):103-110. Epub 2021 Feb 19.

Yu. Gagarin Saratov State Technical University, 410054 Saratov, Russia.

Based on the modified Okun's model, the article evaluates the impact of changes in production volumes on the dynamics of unemployment in Russia and three regional clusters differing in the unemployment rate and behavioral responses to economic shocks. Assessing the specifications of the basic Okun model on the data of 2010-2020 made it possible to identify a cyclical reaction of the unemployment rate in heterogeneous regional clusters to changes in output volumes. Read More

View Article and Full-Text PDF
February 2021

Accuracy of the dynamic signal analysis approach in respiratory mechanics during noninvasive pressure support ventilation: a bench study.

J Int Med Res 2021 Feb;49(2):300060521992184

Department of Pulmonary and Critical Care Medicine, Shanghai Chest Hospital, Shanghai Jiao Tong University, Shanghai, China.

Objective: To evaluate the accuracy of respiratory mechanics using dynamic signal analysis during noninvasive pressure support ventilation (PSV).

Methods: A Respironics V60 ventilator was connected to an active lung simulator to model normal, restrictive, obstructive, and mixed obstructive and restrictive profiles. The PSV was adjusted to maintain tidal volumes (V) that achieved 5. Read More

View Article and Full-Text PDF
February 2021

Tumor Metabolism and Neurocognition in CNS Lymphoma.

Neuro Oncol 2021 Feb 24. Epub 2021 Feb 24.

Helen Diller Family Comprehensive Cancer Center, UCSF.

Background: The mechanistic basis for neurocognitive deficits in CNS lymphoma and other brain tumors is incompletely understood. We tested the hypothesis that tumor metabolism impairs neurotransmitter pathways and neurocognitive function.

Methods: We performed serial cerebrospinal fluid (CSF) metabolomic analyses using liquid chromatography-electrospray tandem mass spectrometry to evaluate changes in the tumor microenvironment in 14 patients with recurrent CNS lymphoma, focusing on 18 metabolites involved in neurotransmission and bioenergetics. Read More

View Article and Full-Text PDF
February 2021

Intracranial Volume Measured and Correlated to Cephalic Index in Syndromic and Nonsyndromic Anterior Brachycephaly.

Ann Plast Surg 2021 Feb 12. Epub 2021 Feb 12.

From the Department of Plastic and Reconstructive Surgery, University Medical Center Utrecht, The Netherlands.

Background: Premature fusion of both coronal sutures (anterior brachycephaly) alters skull shape and potentially affects intracranial volume (ICV). Currently little is known about preoperative ICV in anterior brachycephaly. Aim is to measure preoperative ICV and compare this with normative data. Read More

View Article and Full-Text PDF
February 2021

Estimating Brain Functional Networks Based on Adaptively-Weighted fMRI Signals for MCI Identification.

Front Aging Neurosci 2020 14;12:595322. Epub 2021 Jan 14.

Department of Research and Development, Shanghai United Imaging Intelligence Co. Ltd., Shanghai, China.

Brain functional network (BFN) analysis is becoming a crucial way to explore the inherent organized pattern of the brain and reveal potential biomarkers for diagnosing neurological or psychological disorders. In so doing, a well-estimated BFN is of great concern. In practice, however, noises or artifacts involved in the observed data (i. Read More

View Article and Full-Text PDF
January 2021

Estimating the effect of selective border relaxation on COVID-19 in New Zealand.

N Z Med J 2021 02 5;134(1529):10-25. Epub 2021 Feb 5.

Senior Lecturer, University of Auckland, Section of Epidemiology and Biostatistics, Faculty of Medical and Health Sciences, Auckland.

Aims: We developed a model, updated daily, to estimate undetected COVID-19 infections exiting quarantine following selectively opening New Zealand's borders to travellers from low-risk countries.

Methods: The prevalence of infectious COVID-19 cases by country was multiplied by expected monthly passenger volumes to predict the rate of arrivals. The rate of undetected infections entering the border following screening and quarantine was estimated. Read More

View Article and Full-Text PDF
February 2021

A method for evaluation of patient-specific lean body mass from limited-coverage CT images and its application in PERCIST: comparison with predictive equation.

EJNMMI Phys 2021 Feb 8;8(1):12. Epub 2021 Feb 8.

Department of Nuclear Medicine and PET/CT-MRI Center, The First Affiliated Hospital of Jinan University, No. 613 West Huangpu Road, Guangzhou, 510630, China.

Background: Standardized uptake value (SUV) normalized by lean body mass ([LBM] SUL) is recommended as metric by PERCIST 1.0. The James predictive equation (PE) is a frequently used formula for LBM estimation, but may cause substantial error for an individual. Read More

View Article and Full-Text PDF
February 2021

Relationship of Antenna Work and Ablation Cavity Volume Following Percutaneous Microwave Ablation of Hepatic Tumors.

J Vasc Interv Radiol 2021 04 4;32(4):536-543. Epub 2021 Feb 4.

Department of Vascular and Interventional Radiology, University of Virginia, Charlottesville, Virginia.

Purpose: To formulate a statistical model relating ablation time, power, and work with posttreatment cavity volume following percutaneous microwave ablation of hepatic tumors in vivo.

Materials And Methods: A retrospective review (October 2015 to October 2018) yielded 122 hepatic tumors treated with microwave ablation. Ablation cavity dimensions were measured at 1-month follow-up examination and calculated using an ellipsoid volume formula. Read More

View Article and Full-Text PDF

Relative tidal volume and respiratory airflow estimation using tracheal sound and movement during sleep.

J Sleep Res 2021 Feb 3:e13279. Epub 2021 Feb 3.

KITE, Toronto Rehabilitation Institute-University Health Network, Toronto, ON, Canada.

Airflow is the reference signal to assess sleep respiratory disorders, such as sleep apnea. Previous studies estimated airflow using tracheal sounds in short segments with specific airflow rates, while requiring calibration or a few breaths for tuning the relationship between sound energy and airflow. Airflow-sound relationship can change by posture, sleep stage and airflow rate or tidal volume. Read More

View Article and Full-Text PDF
February 2021

In-vivo lung biomechanical modeling for effective tumor motion tracking in external beam radiation therapy.

Comput Biol Med 2021 Mar 20;130:104231. Epub 2021 Jan 20.

School of Biomedical Engineering, Western University, London, ON, Canada; Department of Medical Biophysics, Western University, London, ON, Canada; Department of Electrical and Computer Engineering, Western University, London, ON, Canada; Imaging Research Laboratories, Robarts Research Institute, London, ON, Canada. Electronic address:

Lung cancer is the most common cause of cancer-related death in both men and women. Radiation therapy is widely used for lung cancer treatment; however, respiratory motion presents challenges that can compromise the accuracy and/or effectiveness of radiation treatment. Respiratory motion compensation using biomechanical modeling is a common approach used to address this challenge. Read More

View Article and Full-Text PDF

Estimating Dining Plate Size From an Egocentric Image Sequence Without a Fiducial Marker.

Front Nutr 2020 14;7:519444. Epub 2021 Jan 14.

Department of Electrical & Computer Engineering, University of Pittsburgh, Pittsburgh, PA, United States.

Despite the extreme importance of food intake in human health, it is currently difficult to conduct an objective dietary assessment without individuals' self-report. In recent years, a passive method utilizing a wearable electronic device has emerged. This device acquires food images automatically during the eating process. Read More

View Article and Full-Text PDF
January 2021

Chemoreduction with topotecan and vincristine: Quantifying tumor response in bilateral retinoblastoma patients.

Pediatr Blood Cancer 2021 Apr 28;68(4):e28882. Epub 2021 Jan 28.

Department of Ophthalmology, Hamilton Eye Institute, University of Tennessee Health Science Center, College of Medicine, Memphis, Tennessee.

Background: Evaluate the efficacy of two courses of vincristine and topotecan (VT) neoadjuvant intravenous chemotherapy in reducing retinoblastoma tumor volumes.

Methods: Twenty-seven patients with previously untreated, bilateral advanced retinoblastoma who were enrolled on a prospective treatment protocol (NCT00186888). Patients underwent high-resolution ophthalmic imaging at diagnosis and were reimaged following treatment with two cycles of VT. Read More

View Article and Full-Text PDF

Estimating PQoS of Video Streaming on Wi-Fi Networks Using Machine Learning.

Sensors (Basel) 2021 Jan 17;21(2). Epub 2021 Jan 17.

Department of Technology Systems, University of Oslo, 2007 Kjeller, Norway.

Video on demand (VoD) services such as YouTube have generated considerable volumes of Internet traffic in homes and buildings in recent years. While Internet service providers deploy fiber and recent wireless technologies such as 802.11ax to support high bandwidth requirement, the best-effort nature of 802. Read More

View Article and Full-Text PDF
January 2021

Estimating the potential impact of implementing pre-emptive pharmacogenetic testing in primary care across the UK.

Br J Clin Pharmacol 2021 Jan 19. Epub 2021 Jan 19.

Boots UK, Thane Road, Nottingham, UK.

Aims: Pharmacogenetics (PGx) in the UK is currently implemented in secondary care for a small group of high-risk medicines. However, most prescribing takes place in primary care, with a large group of medicines influenced by commonly occurring genetic variations. The goal of this study is to quantitatively estimate the volumes of medicines impacted by implementation of a population-level, pre-emptive pharmacogenetic screening programme for nine genes related to medicines frequently dispensed in primary care in 2019. Read More

View Article and Full-Text PDF
January 2021

Physiological changes and compensatory mechanisms by the action of respiratory muscles in a porcine model of phrenic nerve injury.

J Appl Physiol (1985) 2021 Mar 14;130(3):813-826. Epub 2021 Jan 14.

Section of Anaesthesiology and Intensive Care, Department of Surgical Sciences, Uppsala University, Uppsala, Sweden.

Phrenic nerve damage may occur as a complication of specific surgical procedures, prolonged mechanical ventilation, or physical trauma. The consequent diaphragmatic paralysis or dysfunction can lead to major complications. The purpose of this study was to elucidate the role of the nondiaphragmatic respiratory muscles during partial or complete diaphragm paralysis induced by unilateral and bilateral phrenic nerve damage at different levels of ventilatory pressure support in an animal model. Read More

View Article and Full-Text PDF

Noncontrast Computed Tomography e-Stroke Infarct Volume Is Similar to RAPID Computed Tomography Perfusion in Estimating Postreperfusion Infarct Volumes.

Stroke 2021 Jan 12;52(2):634-641. Epub 2021 Jan 12.

Department of Neurology, Marcus Stroke and Neuroscience Center, Grady Memorial Hospital, Emory University School of Medicine, Atlanta, GA (M.B., K.R., G.M.R., L.P., D.C.H., M.R.F., R.G.N.).

Background And Purpose: The e-Stroke Suite software (Brainomix, Oxford, United Kingdom) is a tool designed for the automated quantification of The Alberta Stroke Program Early CT Score and ischemic core volumes on noncontrast computed tomography (NCCT). We sought to compare the prediction of postreperfusion infarct volumes and the clinical outcomes across NCCT e-Stroke software versus RAPID (IschemaView, Menlo Park, CA) computed tomography perfusion measurements.

Methods: All consecutive patients with anterior circulation large vessel occlusion stroke presenting at a tertiary care center between September 2010 and November 2018 who had available baseline infarct volumes on both NCCT e-Stroke Suite software and RAPID CTP as well as final infarct volume (FIV) measurements and achieved complete reperfusion (modified Thrombolysis in Cerebral Infarction scale 2c-3) post-thrombectomy were included. Read More

View Article and Full-Text PDF
January 2021

Impact of macular fluid volume fluctuations on visual acuity during anti-VEGF therapy in eyes with nAMD.

Eye (Lond) 2021 Jan 7. Epub 2021 Jan 7.

Novartis Pharma AG, Basel, Switzerland.

Objectives: To study the effect of repeated retinal thickness fluctuations during the anti-VEGF therapy maintenance phase in neovascular age-related macular degeneration (nAMD).

Methods: Data were extracted from electronic medical records of 381 nAMD patients, aged ≥50 years; baseline VA ≥33 and ≤73 letters; ≥24 months' follow-up and ≥2 optical coherence tomography (OCT) measurements. OCT scans were analysed using an artificial intelligence algorithm that quantified the volumes of intraretinal fluid (IRF), subretinal fluid (SRF), pigment epithelial detachments (PED) and central subfield thickness (CSFT). Read More

View Article and Full-Text PDF
January 2021

Manual and automated tissue segmentation confirm the impact of thalamus atrophy on cognition in multiple sclerosis: A multicenter study.

Neuroimage Clin 2021 25;29:102549. Epub 2020 Dec 25.

Center for Neurological Imaging, Department of Radiology, Brigham and Women's Hospital, Harvard Medical School, 1249 Boylston Street, Boston, MA 02215, USA. Electronic address:

Background And Rationale: Thalamus atrophy has been linked to cognitive decline in multiple sclerosis (MS) using various segmentation methods. We investigated the consistency of the association between thalamus volume and cognition in MS for two common automated segmentation approaches, as well as fully manual outlining.

Methods: Standardized neuropsychological assessment and 3-Tesla 3D-T1-weighted brain MRI were collected (multi-center) from 57 MS patients and 17 healthy controls. Read More

View Article and Full-Text PDF
December 2020

Surgical repair of ischemic mitral regurgitation: one ring does not fit all.

Curr Opin Cardiol 2021 Mar;36(2):154-162

Cardiac Surgery Innovation Lab, Queen's University, Kingston.

Purpose Of Review: The review summarizes the key parameters that can aid in determining the optimal treatment of ischemic mitral regurgitation (IMR).

Recent Findings: Left ventricular (LV) and mitral valve (MV) parameters are important for surgical planning and risk stratification in IMR. Although LV dimensions is one of the main parameters used in the guidelines, volumes more accurately depict LV remodelling. Read More

View Article and Full-Text PDF

Estimating temporal and spatial levels of PAHs in air using rain samples and SPME analysis: Feasibility evaluation in an urban scenario.

Sci Total Environ 2021 Mar 17;762:144184. Epub 2020 Dec 17.

Department of Science and High Technology (DiSAT), University of Insubria, via Valleggio 11, 22100 Como, Italy. Electronic address:

There is a growing interest in evaluating the role of concentration changes of contaminants in temporal and spatial gradients. This is often relevant for fast moving environmental phases such as air and water. In this paper, small volumes of rainwater were sampled as proxy for air concentrations of Polycyclic Aromatic Hydrocarbons (PAHs): rain was collected in three sampling sites (high traffic, restricted traffic and a low traffic zone) in Como. Read More

View Article and Full-Text PDF

Combined quality and dose-volume histograms for assessing the predictive value of Tc-MAA SPECT/CT simulation for personalizing radioembolization treatment in liver metastatic colorectal cancer.

EJNMMI Phys 2020 Dec 14;7(1):75. Epub 2020 Dec 14.

Medical Physics Department, Jules Bordet Institute, Université Libre de Bruxelles, 1 Rue Héger-Bordet, B-1000, Brussels, Belgium.

Background: The relationship between the mean absorbed dose delivered to the tumour and the outcome in liver metastases from colorectal cancer patients treated with radioembolization has already been presented in several studies. The optimization of the personalized therapeutic activity to be administered is still an open challenge. In this context, how well the Tc-MAA SPECT/CT predicts the absorbed dose delivered by radioembolization is essential. Read More

View Article and Full-Text PDF
December 2020

Predictive value of Excel forms based on an automatic calculation of dose equivalent in 2 Gy per fraction in adaptive brachytherapy for cervical cancer.

J Contemp Brachytherapy 2020 Oct 30;12(5):454-461. Epub 2020 Oct 30.

Department of Radiation Oncology, China-Japan Union Hospital of Jilin University, Changchun, China.

Purpose: External beam radiotherapy (EBRT) combined with brachytherapy (BT) is the standard mode of radical radiotherapy for locally advanced cervical cancer. The cumulative equivalent doses in 2 Gy per fraction (EQD) is an important basis for estimating the probability of local control of tumors and monitoring the occurrence of side effects in normal tissues. The purpose of this study was to explore the predictive value of Excel forms based on an automatic calculation in radical adaptive BT for cervical cancer. Read More

View Article and Full-Text PDF
October 2020

Validation of a new open-source method for automatic delineation and dose assessment of the heart and LADCA in breast radiotherapy with simultaneous uncertainty estimation.

Phys Med Biol 2021 Jan 26;66(3):035014. Epub 2021 Jan 26.

Institute of Medical Physics, School of Physics, University of Sydney, Sydney, Australia. Ingham Institute for Applied Medical Research, Liverpool, Australia.

Radiotherapy has been shown to increase risks of cardiotoxicities for breast cancer patients. Automated delineation approaches are necessary for consistent and efficient assessment of cardiac doses in large, retrospective datasets, while patient-specific estimation of the uncertainty in these doses provides valuable additional data for modelling and understanding risks. In this work, we aim to validate the consistency of our previously described open-source software model for automatic cardiac delineation in the context of dose assessment, relative to manual contouring. Read More

View Article and Full-Text PDF
January 2021

Reliability and Reproducibility of the Diameters Method in Rapid Determination of Acute Infarct Volume in Magnetic Resonance Diffusion-Weighted Imaging.

Cerebrovasc Dis 2020 11;49(6):575-582. Epub 2020 Nov 11.

Department of Medical Imaging, Jinling Hospital, Nanjing University School of Medicine, Nanjing, China,

Background: In acute ischemic stroke, diffusion-weighted imaging (DWI) volume is an independent predictive factor of poor outcome and an exclusion criterion for thrombolytic treatment. A simplified diameters method (ABC/2, orthogonal diameter [OD], and the maximum diameter [MD]) was proposed to replace the conventional measuring method and overcome the tedious and time-consuming defects, but its accuracy remains to be determined.

Objective: The objective of this study is to clarify the reliability and reproducibility of the diameter-based estimations in the infarct volume in DWI (Vol-DWI) measured by automated software. Read More

View Article and Full-Text PDF