497 results match your criteria corresponding rois

An examination of histomorphometric relationships in the anterior and posterior human femoral cortex.

J Bone Miner Metab 2021 Mar 13. Epub 2021 Mar 13.

Centre for Forensic Anthropology, Mail Bag Delivery Point M420, University of Western Australia, 35 Stirling Hwy, Crawley, WA, 6009, Australia.

Introduction: Static cortical bone histomorphometry utilised in forensic age-at-death estimation generally examines only the anterior femoral mid-shaft, as biomechanical strain at the posterior femur is thought to result in increased bone remodelling, osteon density and adversely affect age-at-death estimates. As osteon density increases there is a corresponding decrease in geometric variables, such as osteon area and Haversian canal diameter. The present study tests whether the inverse relationship between osteon density and osteon geometry is reflected in a modern documented Australian sample, and if this relationship differs between the anterior and posterior femoral mid-shaft. Read More

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Automatic delineation of cardiac substructures using a region-based fully convolutional network.

Med Phys 2021 Mar 2. Epub 2021 Mar 2.

Department of Radiation Oncology and Winship Cancer Institute, Emory University, Atlanta, GA, USA.

Purpose: Radiation dose to specific cardiac substructures, such as the atria and ventricles, has been linked to post-treatment toxicity and has shown to be more predictive of these toxicities than dose to the whole heart. A deep learning-based algorithm for automatic generation of these contours is proposed to aid in either retrospective or prospective dosimetric studies to better understand the relationship between radiation dose and toxicities.

Methods: The proposed method uses a mask-scoring regional convolutional neural network (RCNN) which consists of five major subnetworks: backbone, regional proposal network (RPN), RCNN head, mask head, and mask-scoring head. Read More

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Convolutional neural network-based ambient light-independent panel digit surveillance technique for infusion pumps.

Proc Inst Mech Eng H 2021 Feb 21:954411921996090. Epub 2021 Feb 21.

Research Institute for Convergence of Biomedical Science and Technology, Pusan National University Yangsan Hospital, Yangsan, Korea.

For effective patient therapy and improved patient safety, it is critical to administer medication accurately in accordance with doctor's prescription. However, accidents owing to the erroneous programing of infusion pumps caused by users have been consistently reported in several documents. In this study, the authors propose a novel surveillance technique for infusion pumps to continuously monitor the variations in panel digits using a convolutional neural network model, and evaluate the performance of the implemented technique. Read More

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February 2021

Application of a Novel Ultra-High Resolution Multi-Detector CT in Quantitative Imaging of Trabecular Microstructure.

Proc SPIE Int Soc Opt Eng 2020 Feb 5;11317. Epub 2020 Mar 5.

Department of Biomedical Engineering, Johns Hopkins University, Baltimore, MD USA 21205.

Purpose: To evaluate the performance of a novel ultra-high resolution multi-detector CT scanner (Canon Aquilion Precision UHR CT), capable of visualizing ~150 μm details, in quantitative assessment of bone microarchitecture. Compared to conventional CT, the spatial resolution of UHR CT begins to approach the size of the trabeculae. This might enable measurements of microstructural correlates of osteoporosis, osteoarthritis, and other bone disease. Read More

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February 2020

Analysis of decay kinetics of the cytosolic calcium transient induced by oxytocin in rat myometrium smooth muscle cells.

J Muscle Res Cell Motil 2021 03 15;42(1):117-127. Epub 2021 Feb 15.

Taras Shevchenko Kyiv National University, Educational-Scientific Center "Biology and Medicine Institute", 64/13 Volodymyrska Street, Kyiv, 01601, Ukraine.

The method of kinetic analysis of the relaxation phase of the mechanical response of the smooth muscle previously proposed by Burdyga and Kosterin was applied to study the dynamics of the decay of oxytocin-induced calcium transients in cytosol of the rat myometrium smooth muscle cell detected by a fluorescence signal generated by a calcium-sensitive probe fluo-4 using a laser scanning confocal microscope. The experimental data were well linearized in the coordinates ln [(F - F)/F] vs lnt (F and F are the current fluorescence intensity of the calcium probe and the fluorescence intensity at the maximum of the calcium transient, respectively, while t is the time). The empirical parameters n and τ were determined by which the maximal normalized relaxation rate V was calculated for five different ROIs (regions of interest) in the myocyte cytosol. Read More

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Diagnostic performance of dynamic volume perfusion CT for differentiation of head and neck cancer from healthy tissue and post-therapeutic changes.

Clin Hemorheol Microcirc 2021 Jan 30. Epub 2021 Jan 30.

Department of Radiology, Charité - Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Campus Benjamin Franklin, Berlin, Germany.

Background: Post-therapeutic tissue is bradytrophic and thus has low perfusion values in PCT. In contrast, malignant tissue is expected to show higher perfusion values as cancer growth partially depends on angiogenesis.

Objectives: This prospective study investigates perfusion computed tomography (PCT) for the post-therapeutic detection of cancer in the head and neck region. Read More

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January 2021

Altered functional network connectivity and working memory dysfunction in adolescents with epilepsy.

Brain Imaging Behav 2021 Feb 2. Epub 2021 Feb 2.

Cincinnati Children's Hospital Medical Center, Cincinnati, OH, 45229, USA.

Adolescents with epilepsy are at risk for deficits in working memory, which could lead to learning difficulties and poor academic outcomes. We used task-based functional magnetic resonance imaging (fMRI) to examine potential disruption in working memory function in adolescents with epilepsy as compared to healthy controls. We recruited 29 adolescents (13-17 years) with non-lesional epilepsy and 20 healthy controls. Read More

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February 2021

Measuring myocardial extracellular volume of the right ventricle in patients with congenital heart disease.

Sci Rep 2021 Jan 29;11(1):2679. Epub 2021 Jan 29.

DZHK (German Centre for Cardiovascular Research), partner site Berlin, Berlin, Germany.

The right ventricle´s (RV) characteristics-thin walls and trabeculation-make it challenging to evaluate extracellular volume (ECV). We aimed to assess the feasibility of RV ECV measurements in congenital heart disease (CHD), and to introduce a novel ECV analysis tool. Patients (n = 39) and healthy controls (n = 17) underwent cardiovascular magnetic resonance T1 mapping in midventricular short axis (SAX) and transverse orientation (TRANS). Read More

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January 2021

Early Segmental White Matter Fascicle Microstructural Damage Predicts the Corresponding Cognitive Domain Impairment in Cerebral Small Vessel Disease Patients by Automated Fiber Quantification.

Front Aging Neurosci 2020 11;12:598242. Epub 2021 Jan 11.

Department of Neurology, Drum Tower Hospital, Medical School and the State Key Laboratory of Pharmaceutical Biotechnology, Institute of Brain Science, Nanjing University, Nanjing, China.

To characterize earlier damage pattern of white matter (WM) microstructure in cerebral small vessel disease (CSVD) and its relationship with cognitive domain dysfunction. A total of 144 CSVD patients and 100 healthy controls who underwent neuropsychological measurements and diffusion tensor imaging (DTI) examination were recruited. Cognitive function, emotion, and gait were assessed in each participant. Read More

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January 2021

Ultra-low-activity total-body dynamic PET imaging allows equal performance to full-activity PET imaging for investigating kinetic metrics of F-FDG in healthy volunteers.

Eur J Nucl Med Mol Imaging 2021 Jan 22. Epub 2021 Jan 22.

Department of Nuclear Medicine, Zhongshan Hospital, Fudan University, No. 180 Fenglin Road, Shanghai, 200032, People's Republic of China.

Purpose: To investigate the feasibility of ultra-low-activity total-body positron emission tomography (PET) dynamic imaging for quantifying kinetic metrics of 2-[F]-fluoro-2-deoxy-D-glucose (F-FDG) in normal organs and to verify its clinical relevance with full-activity imaging.

Methods: Dynamic total-body PET imaging was performed in 20 healthy volunteers, with eight using full activity (3.7 MBq/kg) of F-FDG and 12 using 10× activity reduction (0. Read More

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January 2021

Spatial correspondence of spinal cord white matter tracts using diffusion tensor imaging, fibre tractography, and atlas-based segmentation.

Neuroradiology 2021 Mar 14;63(3):373-380. Epub 2021 Jan 14.

Orthopaedic Biomechanics Laboratory, Sunnybrook Research Institute, 2075 Bayview Ave, S621, Toronto, Ontario, M4N 3M5, Canada.

Purpose: Neuroimaging provides great utility in complex spinal surgeries, particularly when anatomical geometry is distorted by pathology (tumour, degeneration, etc.). Spinal cord MRI diffusion tractography can be used to generate streamlines; however, it is unclear how well they correspond with white matter tract locations along the cord microstructure. Read More

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2D-Perfusion Angiography Using Carbon Dioxide (CO2): A Feasible Tool to Monitor Immediate Treatment Response to Endovascular Therapy of Peripheral Arterial Disease?

Cardiovasc Intervent Radiol 2021 Apr 16;44(4):635-641. Epub 2020 Dec 16.

Institute for Diagnostic and Interventional Radiology, Hannover Medical School, Carl-Neuberg-Str. 1, 30625, Hannover, Germany.

Purpose: Patients with peripheral arterial disease (PAD) or critical limb ischemia (CLI) require revascularization. Traditionally, endovascular therapy (EVT) is performed with iodinated contrast agent (ICM), which can provoke potential deterioration in renal function. CO2 is a safe negative contrast agent to guide vascular procedures, but interpretation of CO2 angiography is challenging. Read More

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Initial results of the use of a novel semiquantitative parameter in three-phase bone scan to predict 99mTc-HMPAO-labeled leukocyte scintigraphy in patients with unilateral total knee replacement.

Nucl Med Commun 2021 Feb;42(2):198-204

Nuclear Medicine Unit, A.R.N.A.S. Ospedali Civico, Di Cristina e Benfratelli, Palermo.

Objectives: The aim of the study was to predict the results of 99mTc-hexamethylpropyleneamine oxime (HMPAO)-labeled autologous leukocytes scintigraphy assessing count ratios in the perfusion (Pr) and blood-pool (BPr) phase images in three-phase bone scan (3PBSr) between the prosthetic knee and the 'healthy' knee and a novel semiquantitative parameter (P/BP ratio) in patients with unilateral knee arthroplasty.

Methods: Patients with unilateral knee arthroplasty and available 3PBS and 99mTc-HMPAO-labeled autologous leukocytes scintigraphic images were searched in two hospitals (A and B). In center A, the perfusion phase was not available. Read More

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February 2021

A radiomics nomogram for the prediction of overall survival in patients with hepatocellular carcinoma after hepatectomy.

Cancer Imaging 2020 Nov 16;20(1):82. Epub 2020 Nov 16.

Department of Hepatobiliary Surgery, the Second Affiliated Hospital of Army Medical University, No. 183 Xinqiao High Street, Shapingba District, Chongqing, 400037, China.

Background: Hepatocellular carcinoma (HCC) is associated with a dismal prognosis, and prediction of the prognosis of HCC can assist in therapeutic decision-makings. An increasing number of studies have shown that the texture parameters of images can reflect the heterogeneity of tumors, and may have the potential to predict the prognosis of patients with HCC after surgical resection. The aim of this study was to investigate the prognostic value of computed tomography (CT) texture parameters in patients with HCC after hepatectomy and to develop a radiomics nomogram by combining clinicopathological factors and the radiomics signature. Read More

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November 2020

A Novel Three-Stage Framework for Association Analysis Between SNPs and Brain Regions.

Front Genet 2020 24;11:572350. Epub 2020 Sep 24.

School of Software, East China Jiaotong University, Nanchang, China.

At present, a number of correlation analysis methods between SNPs and ROIs have been devised to explore the pathogenic mechanism of Alzheimer's disease. However, some of the deficiencies inherent in these methods, including lack of statistical efficacy and biological meaning. This study aims at addressing issues: insufficient correlation by previous methods (relative high regression error) and the lack of biological meaning in association analysis. Read More

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September 2020

Assessing Periprosthetic Bone in Total Wrist Arthroplasty: The Validity of DXA.

J Clin Densitom 2020 Oct 18. Epub 2020 Oct 18.

Division of Orthopaedic Surgery, Oslo University Hospital, Oslo, Norway; Institute of Clinical Medicine, University of Oslo, Oslo, Norway.

Introduction: Dual-energy X-ray absorptiometry (DXA) can measure bone mineral density (BMD) around joint arthroplasties. DXA has never been used in total wrist arthroplasties (TWA). We investigated (1) whether BMD differs between 2 TWAs implanted in the same cadaver forearm, (2) the effect of forearm rotation and wrist extension on measured BMD around TWA in a cadaver, and (3) the precision of DXA in a cadaver and patients. Read More

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October 2020

Automated phantom analysis for gamma cameras and SPECT: A methodology for use in a clinical setting.

J Appl Clin Med Phys 2020 Nov 3;21(11):205-214. Epub 2020 Nov 3.

Department of Radiology and Medical Imaging, UVA Health, Charlottesville, VA, USA.

Purpose: We introduce an automated, quantitative image analysis package for gamma camera and single photon emission computed tomography quality control. Our focus was to produce consistent methods that are feasible in clinical settings and use standard phantoms.

Methods: Four gamma cameras were used to acquire planar images of four-quadrant bar phantoms and projection views of an American College of Radiology (ACR) phantom as part of a standard gamma camera quality control program. Read More

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November 2020

Breast tumor segmentation in 3D automatic breast ultrasound using Mask scoring R-CNN.

Med Phys 2021 Jan 18;48(1):204-214. Epub 2020 Nov 18.

Department of Radiation Oncology and Winship Cancer Institute, Emory University, Atlanta, GA, 30322, USA.

Purpose: Automatic breast ultrasound (ABUS) imaging has become an essential tool in breast cancer diagnosis since it provides complementary information to other imaging modalities. Lesion segmentation on ABUS is a prerequisite step of breast cancer computer-aided diagnosis (CAD). This work aims to develop a deep learning-based method for breast tumor segmentation using three-dimensional (3D) ABUS automatically. Read More

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January 2021

Computational quantitative measures of Gd-EOB-DTPA enhanced MRI hepatobiliary phase images can predict microvascular invasion of small HCC.

Eur J Radiol 2020 Dec 23;133:109361. Epub 2020 Oct 23.

Department of Radiology, Harbin Medical University Cancer Hospital, 150 Haping Road, Harbin 150010, Heilongjiang, China. Electronic address:

Purpose: This study was designed to preoperatively predict microvascular invasion (MVI) of solitary small hepatocellular carcinoma (sHCC) by quantitative analysis of Gd-EOB-DTPA enhanced hepatobiliary phase (HBP) magnetic resonance imaging (MRI).

Method: Sixty-one patients, 19 with and 42 without histologically confirmed MVI following hepatic resection for solitary sHCC (≤ 3 cm), were preoperatively examined with Gd-EOB-DTPA-enhanced MRI. The regions of interest (ROIs) of the hepatic lesions were manually delineated on the maximum cross-sectional area in the HBP images and used to calculate the lesion boundary index (LBI) and marginal gray changes (MGC). Read More

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December 2020

Reliability of quantitative transverse relaxation time mapping with [Formula: see text]-prepared whole brain pCASL.

Sci Rep 2020 10 27;10(1):18299. Epub 2020 Oct 27.

Department of Epileptology, University of Bonn Medical Center, Bonn, Germany.

Arterial spin labeling (ASL) is increasingly applied for cerebral blood flow mapping, but [Formula: see text] relaxation of the ASL signal magnetization is often ignored, although it may be clinically relevant. To investigate the extent, to which quantitative [Formula: see text] values in gray matter (GM) obtained by pseudocontinuous ASL (pCASL) perfusion MRI can be reproduced, are reliable and a potential neuroscientific biomarker, a prospective study was performed with ten healthy volunteers (5F,28 ± 3y) at a 3 T scanner. A [Formula: see text]-prepared pCASL sequence enabled the measurement of quantitative [Formula: see text] and perfusion maps. Read More

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October 2020

Cerebral microinfarcts disruption of remote cortical thickness.

J Neurol Sci 2021 01 4;420:117170. Epub 2020 Oct 4.

Sackler Faculty of Medicine, Tel Aviv University, Tel-Aviv, Israel; Department of Neurology, Rabin Medical Center, Petah-Tikva, Israel. Electronic address:

Introduction: Cerebral microinfarcts (CMI) are common lesions, carrying an important contribution to small-vessel-related cognitive impairment. CMIs were previously found to cause local microstructural damage and disruption of white matter integrity. This study examines CMIs influence on cortical thickness in remote brain areas. Read More

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January 2021

Quantitative serosal and mucosal optical imaging perfusion assessment in gastric conduits for esophageal surgery: an experimental study in enhanced reality.

Surg Endosc 2020 Oct 7. Epub 2020 Oct 7.

Institute of Image-Guided Surgery, IHU-Strasbourg, 1 place de l'Hôpital, 67091, Strasbourg, France.

Introduction/objective: Gastric conduit (GC) is used for reconstruction after esophagectomy. Anastomotic leakage (AL) incidence remains high, given the extensive disruption of the gastric circulation. Currently, there is no reliable method to intraoperatively quantify gastric perfusion. Read More

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October 2020

A Multiscale Consensus Method Using Factor Analysis to Extract Modular Regions in the Functional Brain Network.

Annu Int Conf IEEE Eng Med Biol Soc 2020 07;2020:2824-2828

The brain functional connectivity network is complex, generally constructed using correlations between the regions of interest (ROIs) in the brain, corresponding to a parcellation atlas. The brain is known to exhibit a modular organization, referred to as "functional segregation." Generally, functional segregation is extracted from edge-filtered, and optionally, binarized network using community detection and clustering algorithms. Read More

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Statistical pattern recognition reveals shared neural signatures for displaying and recognizing specific facial expressions.

Soc Cogn Affect Neurosci 2020 10;15(8):803-813

Turku PET Centre and Department of Psychology, University of Turku, FI-20520 Turku, Finland.

Human neuroimaging and behavioural studies suggest that somatomotor 'mirroring' of seen facial expressions may support their recognition. Here we show that viewing specific facial expressions triggers the representation corresponding to that expression in the observer's brain. Twelve healthy female volunteers underwent two separate fMRI sessions: one where they observed and another where they displayed three types of facial expressions (joy, anger and disgust). Read More

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October 2020

Joint Bayesian Estimation of Voxel Activation and Inter-regional Connectivity in fMRI Experiments.

Psychometrika 2020 12 19;85(4):845-869. Epub 2020 Sep 19.

Department of Statistics, University of California, Santa Cruz, CA, USA.

Brain activation and connectivity analyses in task-based functional magnetic resonance imaging (fMRI) experiments with multiple subjects are currently at the forefront of data-driven neuroscience. In such experiments, interest often lies in understanding activation of brain voxels due to external stimuli and strong association or connectivity between the measurements on a set of pre-specified groups of brain voxels, also known as regions of interest (ROI). This article proposes a joint Bayesian additive mixed modeling framework that simultaneously assesses brain activation and connectivity patterns from multiple subjects. Read More

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December 2020

Diffusion tensor imaging in renal artery stenosis: a preliminary report.

Br J Radiol 2020 Nov 9;93(1115):20200101. Epub 2020 Sep 9.

Department of Radiology, Azienda Ospedaliero-Universitaria di Bologna, Via Albertoni 15, Bologna- Italia, Bologna, Italy.

Objective: To investigate the diffusion properties in the kidneys affected by renal artery stenosis (RAS) using diffusion tensor imaging (DTI).

Methods: In this prospective study, 35 patients with RAS and 15 patients without renal abnormalities were enrolled and examined using DTI. Cortical and medullary regions of interest (ROIs) were located to obtain the corresponding values of the apparent diffusion coefficient (ADC) and fractional anisotropy (FA). Read More

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November 2020

Normal appearing brain white matter changes in relapsing multiple sclerosis: Texture image and classification analysis in serial MRI scans.

Magn Reson Imaging 2020 11 2;73:192-202. Epub 2020 Sep 2.

Departement of Computer Science, University of Cyprus, Nicosia, Cyprus; Research Centre on Interactive Media, Smart Systems and Emerging Technologies (RISE CoE), Nicosia, Cyprus. Electronic address:

Objective: There is a clinical interest in identifying normal appearing white matter (NAWM) areas in brain T2-weighted (TW) MRI scans in multiple sclerosis (MS) subjects. These areas are susceptible to disease development and areas need to be studied in order to find potential associations between texture feature changes and disease progression.

Methods: The subjects investigated had a first demyelinating event (Clinically Isolated Syndrome-CIS) at baseline (Time), and the NAWM (i. Read More

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November 2020

Emotion reactivity-related brain network analysis in generalized anxiety disorder: a task fMRI study.

BMC Psychiatry 2020 09 2;20(1):429. Epub 2020 Sep 2.

Nanjing Brain Hospital Affiliated to Nanjing Medical University, No 264, Guangzhou Road, Nanjing, 210029, China.

Background: Generalized anxiety disorder (GAD) is closely associated with emotional dysregulation. Patients with GAD tend to overreact to emotional stimuli and are impaired in emotional regulation. Using emotional regulation task, studies have found hypo-activation in prefrontal cortex (PFC) of GAD patients and concluded with inadequate top-down control. Read More

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September 2020

T1 and T2 MR fingerprinting measurements of prostate cancer and prostatitis correlate with deep learning-derived estimates of epithelium, lumen, and stromal composition on corresponding whole mount histopathology.

Eur Radiol 2021 Mar 2;31(3):1336-1346. Epub 2020 Sep 2.

Department of Biomedical Engineering, Case Western Reserve University, Cleveland, OH, 44106, USA.

Objectives: To explore the associations between T1 and T2 magnetic resonance fingerprinting (MRF) measurements and corresponding tissue compartment ratios (TCRs) on whole mount histopathology of prostate cancer (PCa) and prostatitis.

Materials And Methods: A retrospective, IRB-approved, HIPAA-compliant cohort consisting of 14 PCa patients who underwent 3 T multiparametric MRI along with T1 and T2 MRF maps prior to radical prostatectomy was used. Correspondences between whole mount specimens and MRI and MRF were manually established. Read More

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Association of Regional Bone Synthetic Activities of Vertebral Corners and Vertebral Bodies Quantified Using F-Fluoride Positron Emission Tomography with Bone Mineral Density on Dual Energy X-ray Absorptiometry in Patients with Ankylosing Spondylitis.

J Clin Med 2020 Aug 17;9(8). Epub 2020 Aug 17.

Biomedical Research Institute, Pusan National University Hospital, Busan 49241, Korea.

We investigated whether the bone-synthetic activities of vertebral bodies or vertebral corners quantified using F-fluoride positron emission tomography (PET) was associated with bone mineral density (BMD) at the corresponding lumbar vertebrae in ankylosing spondylitis (AS) at each vertebra level. We analyzed 48 lumbar vertebrae in 12 AS patients who underwent F-fluoride PET and dual energy X-ray absorptiometry (DXA). The mean standardized uptake values (SUVmean) of the vertebral body and corners from L1 to L4 were measured using the spatially separated region of interest (ROI). Read More

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