37,111 results match your criteria scans performed

Cross-cohort generalizability of deep and conventional machine learning for MRI-based diagnosis and prediction of Alzheimer's disease.

Neuroimage Clin 2021 Jun 4;31:102712. Epub 2021 Jun 4.

Department of Radiology and Nuclear Medicine, Erasmus MC, Rotterdam, The Netherlands.

This work validates the generalizability of MRI-based classification of Alzheimer's disease (AD) patients and controls (CN) to an external data set and to the task of prediction of conversion to AD in individuals with mild cognitive impairment (MCI). We used a conventional support vector machine (SVM) and a deep convolutional neural network (CNN) approach based on structural MRI scans that underwent either minimal pre-processing or more extensive pre-processing into modulated gray matter (GM) maps. Classifiers were optimized and evaluated using cross-validation in the Alzheimer's Disease Neuroimaging Initiative (ADNI; 334 AD, 520 CN). Read More

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Robotic-assisted total knee arthroplasty improves the outlier of rotational alignment of the tibial prosthesis using 3DCT measurements.

Knee 2021 Jun 9;31:64-76. Epub 2021 Jun 9.

Department of Orthopedic Surgery, Toho University School of Medicine, Japan. Electronic address:

Background: The aim of the present study was to compare the accuracy of prosthetic alignment with three-dimensional computed tomography (3DCT) measurements following total knee arthroplasty (TKA) performed using a robotic-assisted surgical technique versus a conventional TKA.

Methods: 41 TKAs were performed with a handheld robotic-assisted surgical procedure (Robot group) between 2019 and 2020. Another 41 patients underwent TKA with a conventional manual surgical procedure (Manual group) using the same prosthesis. Read More

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Preoperative histogram parameters of dynamic contrast-enhanced MRI as a potential imaging biomarker for assessing the expression of Ki-67 in prostate cancer.

Cancer Med 2021 Jun 12. Epub 2021 Jun 12.

Department of Radiology, The First Affiliated Hospital of Zhejiang Chinese Medical University, Hangzhou, China.

Purpose: To investigate whether preoperative histogram parameters of dynamic contrast-enhanced MRI (DCE-MRI) can assess the expression of Ki-67 in prostate cancer (PCa).

Materials And Methods: A consecutive series of 76 patients with pathology-proven PCa who underwent routine DCE-MRI scans were retrospectively recruited. Quantitative parameters including the volume transfer constant (K ), rate contrast (K ), extracellular-extravascular volume fraction (V ), and plasma volume (V ) by outlining the three-dimensional volume of interest (VOI) of all lesions were processed. Read More

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Risk factors analysis according to regional distribution of white matter hyperintensities in a stroke cohort.

Eur Radiol 2021 Jun 11. Epub 2021 Jun 11.

Department of Neurology, Hospital del Mar; Neurovascular Research Group, IMIM (Institut Hospital del Mar d'Investigacions Mèdiques), Universitat Autònoma de Barcelona (UAB)/DCEXS-Universitat Pompeu Fabra (UPF), Barcelona, Spain.

Objectives: The spectrum of distribution of white matter hyperintensities (WMH) may reflect different functional, histopathological, and etiological features. We examined the relationships between cerebrovascular risk factors (CVRF) and different patterns of WMH in MRI using a qualitative visual scale in ischemic stroke (IS) patients.

Methods: We assembled clinical data and imaging findings from patients of two independent cohorts with recent IS. Read More

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Diagnostic Accuracy and Failure Mode Analysis of a Deep Learning Algorithm for the Detection of Cervical Spine Fractures.

AJNR Am J Neuroradiol 2021 Jun 11. Epub 2021 Jun 11.

Department of Radiology (M.E.L., J.W.G., J.-P.J.Y.), University of Wisconsin-Madison, Madison, Wisconsin

Background And Purpose: Artificial intelligence decision support systems are a rapidly growing class of tools to help manage ever-increasing imaging volumes. The aim of this study was to evaluate the performance of an artificial intelligence decision support system, Aidoc, for the detection of cervical spinal fractures on noncontrast cervical spine CT scans and to conduct a failure mode analysis to identify areas of poor performance.

Materials And Methods: This retrospective study included 1904 emergent noncontrast cervical spine CT scans of adult patients (60 [SD, 22] years, 50. Read More

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18F-Choline PET/CT, MRI, and Software-Based Image Fusion Analysis in Patients With Primary Hyperparathyroidism.

Clin Nucl Med 2021 Jun 10. Epub 2021 Jun 10.

From the Institute of Nuclear Medicine and Endocrinology, Kepler University Hospital Linz GmbH Medical Faculty, Johannes Kepler University Linz Central Radiology Institute Department of General Surgery, Kepler University Hospital Linz GmbH, Linz Department of Nuclear Medicine, Medical University of Innsbruck, Innsbruck, Austria.

Purpose: The aim of this study was to evaluate the diagnostic performance of 18F-choline PET and MRI in patients with primary hyperparathyroidism. Furthermore, the additional value of software-based PET/MRI scan fusion was analyzed.

Patients And Methods: This retrospective study includes 42 patients (38 women) with an age between 32. Read More

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Y-90 SIRT: evaluation of TCP variation across dosimetric models.

EJNMMI Phys 2021 Jun 10;8(1):45. Epub 2021 Jun 10.

Department of Radiation Oncology, University of Michigan, Ann Arbor, 48109, MI, USA.

Introduction: Much progress has been made in implementing selective internal radiation therapy (SIRT) as a viable treatment option for hepatic malignancies. However, there is still much need for improved options for calculating the amount of activity to be administered. To make advances towards this goal, this study examines the relationship between predicted biological outcomes of liver tumors via tumor control probabilities (TCP) and parenchyma via normal tissue complication probabilities (NTCP) given variations in absorbed dose prescription methodologies. Read More

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The cumulative effects and clinical safety of repeat magnetic resonance imaging on an MRI-conditional pacemaker system at 1.5 tesla.

Heart Rhythm O2 2021 Feb 18;2(1):73-79. Epub 2020 Dec 18.

Divisions of Cardiovascular Medicine and Mallinckrodt Institute of Radiology, Washington University, Saint Louis, Missouri.

Background: Studies have demonstrated magnetic resonance imaging (MRI) safety in the presence of MRI-conditional permanent pacemakers (PPM). However, since patients' care may require serial MRIs, it is necessary to evaluate device safety and performance after multiple scans.

Objectives: We evaluated safety and performance of MRI-conditional PPMs after serial MRIs over various anatomic regions performed during a multicenter, prospective, single-arm study (ProMRI). Read More

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February 2021

Cardiac 18F-FDG Positron Emission Tomography: An Accurate Tool to Monitor Metabolic and Functional Alterations in Murine Myocardial Infarction.

Front Cardiovasc Med 2021 25;8:656742. Epub 2021 May 25.

Department of Nuclear Medicine, University Hospital, Ludwig-Maximilians-Universität (LMU) Munich, Munich, Germany.

Cardiac monitoring after murine myocardial infarction, using serial non-invasive cardiac 18F-FDG positron emissions tomography (PET) represents a suitable and accurate tool for studies. Cardiac PET imaging enables tracking metabolic alterations, heart function parameters and provides correlations of the infarct size to histology. ECG-gated 18F-FDG PET scans using a dedicated small-animal PET scanner were performed in mice at baseline, 3, 14, and 30 days after myocardial infarct (MI) by permanent ligation of the left anterior descending (LAD) artery. Read More

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Early Changes in [F]FDG Uptake as a Readout for PI3K/Akt/mTOR Targeted Drugs in HER-2-Positive Cancer Xenografts.

Mol Imaging 2021 25;2021:5594514. Epub 2021 May 25.

Molecular Imaging Center Antwerp, University of Antwerp, Universiteitsplein 1, B-2610 Wilrijk, Belgium.

We investigated the potential use of [F]FDG PET as a response biomarker for PI3K pathway targeting therapies in two HER-2-overexpressing cancer models. . CD-1 nude mice were inoculated with HER-2-overexpressing JIMT1 (trastuzumab-resistant) or SKOV3 (trastuzumab-sensitive) human cancer cells. Read More

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Changes of Neuroretinal Rim and Retinal Nerve Fiber Layer Thickness Assessed by Optical Coherence Tomography After Filtration Surgery in Glaucomatous Eyes.

Clin Ophthalmol 2021 3;15:2335-2344. Epub 2021 Jun 3.

Ludwig-Maximilians University, Eye Clinic, Campus Innenstadt, Munich, D-80336, Germany.

Purpose: Lowering the intraocular pressure (IOP) in patients with primary open-angle glaucoma (POAG) with filtration surgery can induce morphological changes to the bulbus and structures of the retina. In this study, we have evaluated changes of Bruch's membrane-based parameters and retinal nerve fiber layer (RNFL) derived by spectral-domain optical coherence tomography (SD-OCT) in eyes that have undergone glaucoma filtration surgery.

Patients And Methods: SD-OCT imaging of the optic nerve head (ONH) and of the RNFL was performed in 54 eyes of 54 patients with medically uncontrolled POAG before and after IOP-lowering surgery (trabeculectomy or deep sclerectomy). Read More

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Extradural anterior clinoidectomy through endoscopic transorbital approach: laboratory investigation for surgical perspective.

Acta Neurochir (Wien) 2021 Jun 10. Epub 2021 Jun 10.

Laboratory of Surgical Neuroanatomy, Faculty of Medicine, University of Barcelona, Barcelona, Spain.

Background: The endoscopic transorbital approach (eTOA) is a new mini-invasive procedure used to explore different areas of the skull base. Authors propose an extradural anterior clinoidectomy (AC) through this corridor, defining the anatomical landmarks of the anterior clinoid process (ACP) projection onto the posterior orbit wall and the technical feasibility of this approach. We describe the exposure of the opticocarotid region and the surgical freedom and the angles of attack obtained with this novel approach. Read More

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"Benefits of the pedicled osteoplastic flap as a surgical approach of mastoidectomy in cochlear implant surgery".

Eur Arch Otorhinolaryngol 2021 Jun 10. Epub 2021 Jun 10.

Otorhinolaryngology Department, PhD, National Institute of Rehabilitation, Mexico City, Mexico.

Objective: To evaluate the esthetic and functional results of an osteoplastic flap for mastoid cavity closure in cochlear implant surgery.

Study Design: Double-blind, prospective, randomized clinical trial.

Setting: tertiary referral center. Read More

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Estimated Utility of the Short-term Assessment of Glaucoma Progression Model in Clinical Practice.

JAMA Ophthalmol 2021 Jun 10. Epub 2021 Jun 10.

Hamilton Glaucoma Center, Shiley Eye Institute, Viterbi Family Department of Ophthalmology, University of California, San Diego, La Jolla.

Importance: Clinical trials of glaucoma therapies focused on protecting the optic nerve have required large sample sizes and lengthy follow-up to detect clinically relevant change due to its slow rate of progression. Whether shorter trials may be possible with more frequent testing and use of rate of change as the end point warrants further investigation.

Objective: To describe the design for the Short-term Assessment of Glaucoma Progression (STAGE) model and provide guidance on sample size and power calculations for shorter clinical trials. Read More

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Greater trochanteric pain syndrome in women: Analysis of magnetic resonance, sagittal alignment, muscular strength and endurance of the hip and trunk.

Int J Rheum Dis 2021 Jun 10. Epub 2021 Jun 10.

Postgraduation program in Rehabilitation Sciences, UEL/UNOPAR, Paraná, Brazil.

Introduction: There are many studies on the Greater Trochanteric Pain Syndrome (GTPS), however its relationship with radiographic and biomechanics parameters is not established.

Objective: To compare the magnetic resonance images (MRI) of the hip, radiographic parameters of sagittal alignment (pelvic incidence, sacral slope and lumbar lordosis), muscular strength and endurance in women with and without GTPS.

Methods: Forty women, age over 45, IMC <30 Kg/m and sedentary, were recruited and distributed in two groups: GTPS group (GTPSG, n = 20) and Control group (CG, n = 20). Read More

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Body Composition Parameters May Be Prognostic Factors in Upper Urinary Tract Urothelial Carcinoma Treated by Radical Nephroureterectomy.

Front Oncol 2021 24;11:679158. Epub 2021 May 24.

West China Hospital, Sichuan University, Chengdu, China.

Objective: This study assessed the association between body composition and prognosis of patients with upper urinary tract urothelial carcinoma (UTUC) patients treated by radical nephroureterectomy.

Methods: We retrospectively collected baseline data on age, sex, body mass index (BMI), hypertension, diabetes, and tumor-related factors. Computed tomography (CT) scans were performed to measure body composition parameters such as muscle attenuation (MA), total abdominal muscle area (TAMA), visceral fat area (VFA), intermuscular fat area (IMF), and lateral/posterior perirenal fat thickness (L/P PNF), visceral fat density (VD), and subcutaneous fat density (SD). Read More

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Palmar Musculature: Does It Affect the Development of Carpal Tunnel Syndrome? A Pilot Study.

J Wrist Surg 2021 Jun 3;10(3):196-200. Epub 2021 Jan 3.

Departments of Orthopaedic Surgery and Radiology, School of Medicine, New York University, New York.

 The etiology of carpal tunnel syndrome (CTS) is multifactorial. Static mechanical characteristics of CTS have been described, but dynamic (muscular) parameters remain obscure. We believe that musculature overlying the transverse carpal ligament may have an effect on carpal tunnel pressure and may explain the prevalence of CTS in manual workers. Read More

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Immediate Analgesic Effect of Acupuncture in Patients With Primary Dysmenorrhea: A fMRI Study.

Front Neurosci 2021 24;15:647667. Epub 2021 May 24.

Acupuncture and Tuina School, Chengdu University of Traditional Chinese Medicine, Chengdu, China.

Primary dysmenorrhea (PDM) is a common gynecological disease characterized by lower abdominal pain. Acupuncture is considered a good alternative therapy for PDM. However, the central mechanism of the analgesic effect of acupuncture is largely unknown. Read More

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The Effect of Congenital and Acquired Bilateral Anophthalmia on Brain Structure.

Neuroophthalmology 2021 1;45(2):75-86. Epub 2021 Mar 1.

Oxford Eye Hospital, John Radcliffe Hospital, Oxford, UK.

The aim of this study was to compare the pattern of changes in brain structure resulting from congenital and acquired bilateral anophthalmia. Brain structure was investigated using 3T magnetic resonance imaging (MRI) in Oxford (congenital) or Manchester (acquired). T1-weighted structural and diffusion-weighted scans were acquired from people with anophthalmia and sighted control participants. Read More

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Vitamin D Status in Patients with Atrial Fibrillation and Heart Failure - Is there a Link?

Clin Lab 2021 Jun;67(6)

Background: The disturbed pleiotropic functions of vitamin D are related to numerous chronic non-skeletal diseases. The role of vitamin D insufficiency/deficiency in cardiovascular diseases (CVD) is controversial. Therefore, the aim was to study the vitamin D status in CVD patients and to reveal possible relationships with CVD risk factors. Read More

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The role of cortical perforations in allogeneic block grafting for lateral augmentation in maxilla: A randomized clinical trial.

Clin Implant Dent Relat Res 2021 Jun 9. Epub 2021 Jun 9.

Department of Dental Clinical Specialties, Faculty of Dentistry, Complutense University, Madrid, Spain.

Background: The need of decortication on the recipient site remains unclear for bone regeneration. To our knowledge, there are no human clinical trials that studied the influence of decortication on cancellous allogeneic block grafting.

Purpose: The aim of the present study is to evaluate the influence of perforating the cortex of the recipient site on cancellous allogeneic block graft integration and revascularization in the maxilla. Read More

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Early Neurological Deterioration and Hypoperfusion Volume Ratio on Arterial Spin Labeling in Patients with Acute Ischemic Stroke.

J Stroke Cerebrovasc Dis 2021 Jun 6;30(8):105885. Epub 2021 Jun 6.

Department of Neurology, Jinling Hospital Affiliated to Nanjing Medical University, Nanjing, Jiangsu Province, China. Electronic address:

Background: Arterial spin labeling (ASL) is a magnetic resonance imaging (MRI) technique used to quantify cerebral blood perfusion by labeling blood water as it flows throughout the brain. Hypoperfusion volume ratio (HVR) can be calculated using proportional hypoperfusion volume on ASL-based cerebral blood flow (CBF). This study aimed to explore the relation between HVR and early neurological deterioration (END) in AIS patients. Read More

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Pulmonary embolism severity before and during the COVID-19 pandemic.

Br J Radiol 2021 Jun 9:20210264. Epub 2021 Jun 9.

Department of Radiology, Royal Infirmary of Edinburgh, Edinburgh, UK.

Objectives: Early in the coronavirus 2019 (COVID-19) pandemic, a high frequency of pulmonary embolism was identified. This audit aims to assess the frequency and severity of pulmonary embolism in 2020 compared to 2019.

Methods: In this retrospective audit, we compared computed tomography pulmonary angiography (CTPA) frequency and pulmonary embolism severity in April and May 2020, compared to 2019. Read More

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Cerebral and tumoral blood flow in adult gliomas: a systematic review of results from magnetic resonance imaging.

Br J Radiol 2021 Jun 9:20201450. Epub 2021 Jun 9.

Department of Neurosurgery, Salford Royal NHS Foundation Trust, Salford, UK.

Objective: Blood flow is the rate of blood movement and relevant to numerous processes, though understudied in gliomas. The aim of this review was to pool blood flow metrics obtained from MRI modalities in adult supratentorial gliomas.

Methods: MEDLINE, EMBASE and the Cochrane database were queried 01/01/2000-31/12/2019. Read More

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New mutation in WT1 gene in a boy with an incomplete form of Denys-Drash syndrome: A CARE-compliant case report.

Medicine (Baltimore) 2021 May;100(19):e25864

Children's Republican Clinical Hospital of the Ministry of Health of the Republic of Tatarstan, Kazan, Russian Federation.

Rationale: Pediatric patients with WTl-associated syndromes (including Wilms' tumor-aniridia syndrome and Denys-Drash syndrome), Perlman syndrome, mosaic aneuploidy, and Fanconi anemia with a biallelic breast cancer type 2 susceptibility protein mutation have the highest risk of developing Wilms' tumor.

Patient Concerns And Diagnosis: We describe a patient with bilateral metachronous Wilms' tumor, ambiguous genitalia characterized by 46, XY disorder of sexual development (DSD) with scrotal hypospadias and bilateral abdominal cryptorchidism, but without nephropathy. At the age of 7 months, the child underwent left nephrectomy with left orchiopexy. Read More

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Chronic eosinophilic pneumonitis due to the inhalation of aerosolized face lotion: A case report.

Medicine (Baltimore) 2021 May;100(19):e25860

Respiratory Disease Center, Fukujuji Hospital, Japan Anti-Tuberculosis Association (JATA), Kiyose City, Tokyo.

Rationale: Inhalation of toxic agents can induce eosinophilic pneumonia. However, only a few case reports demonstrate that exposure to materials can induce chronic eosinophilic pneumonia (CEP). Here, we describe a rare case of CEP with mild alveolar hemorrhage due to the inhalation of aerosols from face lotion. Read More

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Magnetic resonance radiomics signatures for predicting poorly differentiated hepatocellular carcinoma: A SQUIRE-compliant study.

Medicine (Baltimore) 2021 May;100(19):e25838

Department of Radiology, Beijing Friendship Hospital, Capital Medical University, Beijing, China.

Abstract: Radiomics contributes to the extraction of undetectable features with the naked eye from high-throughput quantitative images. In this study, 2 predictive models were constructed, which allowed recognition of poorly differentiated hepatocellular carcinoma (HCC). In addition, the effectiveness of the as-constructed signature was investigated in HCC patients. Read More

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Posterior Extra-articular Ischiofemoral Impingement Can Be Caused by the Lesser and Greater Trochanter in Patients With Increased Femoral Version: Dynamic 3D CT-Based Hip Impingement Simulation of a Modified FABER Test.

Orthop J Sports Med 2021 May 28;9(5):2325967121990629. Epub 2021 May 28.

Department of Orthopaedic Surgery, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland.

Background: Posterior extra-articular hip impingement has been described for valgus hips with increased femoral version (FV). These patients can present clinically with lack of external rotation (ER) and extension and with a positive posterior impingement test. But we do not know the effect of the combination of deformities, and the impingement location in early flexion is unknown. Read More

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Comparison of the effectiveness of celiac versus common hepatic artery injection for the detection of hepatocellular carcinoma and of the feeding artery on cone-beam computed tomographs obtained during hepatic angiography.

Acta Radiol Open 2021 Feb 22;10(2):2058460121994735. Epub 2021 Feb 22.

Department of Diagnostic Radiology, Graduate School of Biomedical and Health Sciences, Hiroshima University, Hiroshima, Japan.

Background: Cone-beam computed tomography (CBCT) has been widely used during transcatheter arterial chemoembolization for hepatocellular carcinoma.

Purpose: To evaluate the sensitivity of CBCT for the detection of hepatocellular carcinomas and the tumor feeders by comparing celiac artery (CA) and common hepatic artery (CHA) injection.

Material And Methods: We retrospectively enrolled 30 patients (52 hepatocellular carcinoma lesions) who had undergone CBCT-assisted transcatheter arterial chemoembolization. Read More

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February 2021

Accuracy of Microcomputed Tomography in Detecting Dentinal Cracks: A Correlative Study with Scanning Electron and Operative Microscopy.

Scanning 2021 15;2021:5571123. Epub 2021 May 15.

Faculty of Dentistry, Iguaçu University, Nova Iguaçu, RJ, Brazil.

The aim of the study was to evaluate the accuracy of microcomputed tomography (mCT) to detect dentinal cracks when compared with scanning electron microscopy (SEM) and operating microscopy (OM). Different conditions of pixel size (10 or 17 m), sample moisture (dry/moist), and transillumination (with/without) were evaluated. Additionally, the influence of the dentinal defect width on its detection was analyzed. Read More

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