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1.
BMC Med Imaging ; 24(1): 35, 2024 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-38321400

RESUMO

BACKGROUND: Sagittal and coronal standing radiographs have been the standard imaging for assessing spinal alignment. However, their disadvantages include distortion at the image edges and low interobserver reliability in some parameters. EOS® is a low-dose biplanar digital radiographic imaging system that can avoid distortion by obtaining high-definition images. METHODS: This study aimed to evaluate spinopelvic parameters in conventional lateral C1S1 upright radiographs and EOS® images and compare them. Patients with non-deformity changes were subjected to routine clinical examinations. Plain AP and lateral X-ray radiographs were obtained along the entire spine length. Patients were also referred for full-length EOS® of the spine. Thoracic Kyphosis (TK), Lumbar Lordosis (LL), Pelvic Tilt (PT), Sacral Slope (SS), Pelvic Incidence (PI), and Sagittal Vertical Axis (SVA) were measured in the two studies by an orthopedic surgeon and a radiologist using PACS software. Also, the orthopedic surgeon evaluated the studies again after two weeks. Intra- and inter-observer reliability was then assessed using the interclass correlation coefficient (ICC). Also, the coefficient of variation was used to assess intra- and inter-observer reliability. Bland-Altman plots were drawn for each parameter. RESULTS: The mean age was 48.2 ± 6.6 years. Among the 50 patients, 30 (60%) were female. The mean ICC for TK, LL, PT, SS, PI, and SVA in EOS® images are 0.95, 0.95, 0.92, 0.90, 0.94, and 0.98, respectively, and in C1S1 radiography images, it was 0.92, 0.87, 0.94, 0.88, 0.93, and 0.98, respectively which shows good to excellent results. The coefficient of variation for intraobserver reliability was relatively low (< 18.6%), while it showed higher percentages in evaluating interobserver reliability (< 54.5%). Also, the Bland-Altman plot showed good agreement for each parameter. CONCLUSION: Spinopelvic parameters, e.g., TK, LL, SS, PI, and SS, in EOS® are reliable and comparable to those in conventional lateral upright C1S1 radiographs.


Assuntos
Cifose , Coluna Vertebral , Humanos , Feminino , Adulto , Pessoa de Meia-Idade , Masculino , Reprodutibilidade dos Testes , Cifose/diagnóstico por imagem , Radiografia , Posição Ortostática , Vértebras Lombares/cirurgia , Estudos Retrospectivos
2.
PLoS One ; 19(2): e0292069, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38324512

RESUMO

INTRODUCTION: Adolescent Idiopathic Scoliosis (AIS) is a 3D deformity of the spine that affects 3% of the adolescent population. Conservative treatments like bracing aim to halt the progression of the curve to the surgical threshold. Computer-aided design and manufacturing (CAD/CAM) methods for brace design and manufacturing are becoming increasingly used. Linked to CAD/CAM and 3D radiographic reconstruction techniques, we developed a finite element model (FEM) enabling to simulate the brace effectiveness before its fabrication, as well as a semi-automatic design processes. The objective of this randomized controlled trial is to compare and validate such FEM semi-automatic algorithm used to design nighttime Providence-type braces. METHODS AND ANALYSIS: Fifty-eight patients with AIS aged between 10 to 16-years and skeletally immature will be recruited. At the delivery stage, all patients will receive both a Providence-type brace optimized by the semi-automatic algorithm leveraging a patient-specific FEM (Test) and a conventional Providence-type brace (Control), both designed using CAD/CAM methods. Biplanar radiographs will be taken for each patient with both braces in a randomized crossover approach to evaluate immediate correction. Patients will then be randomized to keep either the Test or Control brace as prescribed with a renewal if necessary, and will be followed over two years. The primary outcome will be the change in Cobb angle of the main curve after two years. Secondary outcomes will be brace failure rate, quality of life (QoL) and immediate in-brace correction. This is a single-centre study, double-blinded (participant and outcome assessor) randomized controlled trial (RCT). TRIAL REGISTRATION NUMBER: ClinicalTrials.gov: NCT05001568.


Assuntos
Cifose , Escoliose , Humanos , Adolescente , Criança , Escoliose/diagnóstico por imagem , Escoliose/terapia , Coluna Vertebral , Radiografia , Tratamento Conservador/métodos , Resultado do Tratamento , Ensaios Clínicos Controlados Aleatórios como Assunto
3.
Curr Sports Med Rep ; 23(2): 45-52, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38315432

RESUMO

ABSTRACT: Legg-Calvé-Perthes disease (LCPD), or idiopathic avascular necrosis of the proximal capital femoral epiphysis in children, has a variable presentation and can result in significant femoral head deformity that can lead to long-term functional deficits. Plain radiographic imaging is crucial in diagnosing LCPD and guiding treatment. Although the etiology of LCPD remains unknown, the evolution of the disease has been well characterized to include the phases of ischemia, revascularization, and reossification. The mechanical weakening during these phases of healing place the femoral head at high risk of deformity. Treatment of LCPD, therefore, focuses on minimizing deformity through operative and nonoperative strategies to reduce the risk of premature osteoarthritis. Advanced imaging using perfusion MRI may refine surgical decision making in the future, and biological treatments to improve femoral head healing are on the horizon.


Assuntos
Doença de Legg-Calve-Perthes , Criança , Humanos , Doença de Legg-Calve-Perthes/terapia , Doença de Legg-Calve-Perthes/diagnóstico por imagem , Cabeça do Fêmur/diagnóstico por imagem , Radiografia , Imageamento por Ressonância Magnética , Tomada de Decisões
4.
Sci Rep ; 14(1): 2827, 2024 02 03.
Artigo em Inglês | MEDLINE | ID: mdl-38310147

RESUMO

This study aimed to determine the prevalence of osteoarthritis (OA) and associated clinical signs in young dogs. Owners of dogs aged 8 months-4 years from a single practice, were contacted in random order, to participate in a general health screen. Clinical and orthopedic examinations were performed. Each joint was scored for pain reactions (0-4). Orthogonal radiographs of all joints were made under sedation. Each joint was scored for radiographic OA (rOA) severity on an 11-point scale. Clinical OA (cOA) was defined as an overlap of rOA and joint pain in ≥ 1 joint. Owners completed OA questionnaires. The owners of 123 dogs agreed to participate. Overall, 39.8% (49/123) of dogs had rOA in ≥ 1 joint, and 16.3% (20/123) or 23.6% (29/123) dogs had cOA, depending on the cut-off value of joint pain; moderate (2), or mild (1), respectively. Owners of dogs with cOA observed signs of impairment in approximately 30% of cases. Only 2 dogs with cOA were receiving OA pain management. The most commonly affected joints in descending order of frequency were elbow, hip, tarsus, and stifle. Radiographically visible OA is common in young dogs, and 40-60% of dogs with rOA had cOA. However, OA-pain appears underdiagnosed and undertreated in young dogs.


Assuntos
Osteoartrite , Cães , Animais , Prevalência , Osteoartrite/diagnóstico por imagem , Osteoartrite/epidemiologia , Osteoartrite/veterinária , Artralgia , Dor/diagnóstico por imagem , Dor/epidemiologia , Dor/etiologia , Radiografia
6.
Am J Forensic Med Pathol ; 45(1): 77-80, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38305300

RESUMO

ABSTRACT: As the fifth leading cause of death in individuals aged 1 to 64 years in the United States, forensic pathologists frequently encounter firearm-related deaths and are trained to approach these cases by utilizing information from the investigation, radiographs, and autopsy findings to discern the logical sequence of events that lead to death. We also emphasize the importance and utility of various factors such as bullet wound characteristics, type of ammunition used, and type of tissues involved in a forensic pathologist's determination of events and in medicolegal investigations. However, the unusual presentations of firearm-related deaths can cause confusion and even frustration when there are contradicting circumstances or findings at work. We present the case of a 61-year-old woman with an atypical pattern of 2 distinct irregular entrance gunshot wounds determined to be caused by a single projectile.


Assuntos
Armas de Fogo , Ferimentos por Arma de Fogo , Feminino , Humanos , Pessoa de Meia-Idade , Ferimentos por Arma de Fogo/diagnóstico por imagem , Autopsia , Radiografia , Balística Forense
8.
Acta Orthop ; 95: 108-113, 2024 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-38347730

RESUMO

BACKGROUND AND PURPOSE: The efficacy of bracing larger curves in adolescent idiopathic scoliosis (AIS) patients is uncertain. We aimed to assess the influence of night-time bracing in AIS patients with main curves exceeding 40° Cobb angle at brace initiation. METHODS: We reviewed AIS patients treated with nighttime braces between 2005 and 2018. Patients with curves ≥ 25° and estimated growth potential were included. Patients were monitored with radiographs from brace initiation until brace weaning at skeletal maturity. Patients were grouped based on curve magnitude at initial evaluation: a control group (25-39°) and a large-curves group (≥ 40°). Progression was defined as > 5° increase. RESULTS: We included 299 patients (control group, n = 125; large-curves group, n = 174). In the control group, 65 (52%) patients progressed compared with 101 (58%) in the large-curves group (P = 0.3). The lower-end vertebra (LEV) shifted distally post-bracing in 41 (23%) patients in the largecurves group. Patients with progressive large curves were younger (age 13.2 [SD 1.5] vs. 13.9 [SD 1.1], P = 0.009) and more premenarchal (n = 36 [42%] vs. n = 6 [9%], P < 0.001) compared with non-progressive large curves. CONCLUSION: Progression risk in patients with curves exceeding 40° treated with night-time bracing is similar to smaller curves. The LEV moved distally in almost one-fourth of the larger curves, possibly affecting fusion levels in cases of surgery.


Assuntos
Cifose , Escoliose , Humanos , Adolescente , Escoliose/diagnóstico por imagem , Escoliose/terapia , Coluna Vertebral , Radiografia , Braquetes , Progressão da Doença , Estudos Retrospectivos , Resultado do Tratamento
9.
Oper Orthop Traumatol ; 36(1): 56-72, 2024 Feb.
Artigo em Alemão | MEDLINE | ID: mdl-38319324

RESUMO

Conventional or digital radiography is still the basis of imaging diagnostics of the skeletal system in pediatric patients. It is considered the gold standard for diagnosis, treatment selection, and follow-up. In addition, procedures such as ultrasound, computed tomography (CT), magnetic resonance imaging (MRI), and also nuclear medicine techniques can and should be used. It is advantageous to use trained radiology technicians who are familiar with the handling of children in X­ray diagnostics. If there is no dedicated pediatric radiology department, it is recommended to follow the guidelines from radiology societies (as low as reasonably achievable [ALARA]) and radiation protection commissions. The present article describes how state-of-the-art tools such as dose monitoring systems and software-controlled image processing and also postprocessing can be used. The article provides information on how the various modalities can be optimally used in order to achieve the best result, i.e., diagnosis, with the least possible effort and burden for the child.


Assuntos
Traumatologia , Criança , Humanos , Resultado do Tratamento , Tomografia Computadorizada por Raios X/métodos , Radiografia , Imageamento por Ressonância Magnética
10.
Biomed Phys Eng Express ; 10(2)2024 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-38320327

RESUMO

The inherent biological hazards associated with ionizing radiation necessitate the implementation of effective shielding measures, particularly in medical applications. Interventional radiology, in particular, poses a unique challenge as it often exposes medical personnel to prolonged periods of high x-ray doses. Historically, lead and lead-based compounds have been the primary materials employed for shielding against photons. However, the drawbacks of lead, including its substantial weight causing personnel's inflexibility and its toxicity, have raised concerns regarding its long-term impact on both human health and the environment. Barium tantalate has emerged as a promising alternative, due to its unique attenuation properties against low-energy x-rays, specifically targeting the weak absorption area of lead. In the present study, we employ the Geant4 Monte Carlo simulation tool to investigate various formulations of barium tantalate doped with rare earth elements. The aim is to identify the optimal composition for shielding x-rays in the context of interventional radiology. To achieve this, we employ a reference x-ray spectrum typical of interventional radiology procedures, with energies extending up to 90 keV, within a carefully designed simulation setup. Our primary performance indicator is the reduction in air kerma transmission. Furthermore, we assess the absorbed doses to critical organs at risk within a standard human body phantom protected by the shield. Our results demonstrate that specific concentrations of the examined rare earth impurities can enhance the shielding performance of barium tantalate. To mitigate x-ray exposure in interventional radiology, our analysis reveals that the most effective shielding performance is achieved when using barium tantalate compositions containing 15% Erbium or 10% Samarium by weight. These findings suggest the possibility of developing lead-free shielding solutions or apron for interventional radiology personnel, offering a remarkable reduction in weight (exceeding 30%) while maintaining shielding performance at levels comparable to traditional lead-based materials.


Assuntos
Proteção Radiológica , Radiologia Intervencionista , Humanos , Bário , Radiometria , Proteção Radiológica/métodos , Radiografia
11.
Int J Mol Sci ; 25(3)2024 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-38338829

RESUMO

Molecular Dynamics simulations study material structure and dynamics at the atomic level. X-ray and neutron scattering experiments probe exactly the same time- and length scales as the simulations. In order to benchmark simulations against measured scattering data, a program is required that computes scattering patterns from simulations with good single-core performance and support for parallelization. In this work, the existing program Sassena is used as a potent solution to this requirement for a range of scattering methods, covering pico- to nanosecond dynamics, as well as the structure from some Ångströms to hundreds of nanometers. In the case of nanometer-level structures, the finite size of the simulation box, which is referred to as the finite size effect, has to be factored into the computations for which a method is described and implemented into Sassena. Additionally, the single-core and parallelization performance of Sassena is investigated, and several improvements are introduced.


Assuntos
Benchmarking , Simulação de Dinâmica Molecular , Raios X , Radiografia , Nêutrons , Difração de Nêutrons/métodos , Espalhamento a Baixo Ângulo , Difração de Raios X
12.
Sensors (Basel) ; 24(3)2024 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-38339610

RESUMO

(1) Background: The peripherally inserted central catheter (PICC) is commonly used in medicine. The tip position was shown to be a major determinant in PICC function and related complications. Recent advances in ECG guidance might facilitate daily practice. This study aimed to compare two ECG techniques, in terms of their tip-position accuracy, puncture site layout, and signal quality; (2) Methods: This randomized open study (1:1) included 320 participants. One PICC guidance technique used ECG signal transmission with saline (ST); the other technique used a guidewire (WT). Techniques were compared by the distance between the catheter tip and the cavoatrial junction (DCAJ) on chest X-rays, insertion-point hemostasis time, and the extracorporeal catheter length between the hub and the insertion point; (3) Results: The mean DCAJs were significantly different between ST (1.36 cm, 95% CI: 1.22-1.37) and WT (1.12 cm, 95% CI: 0.98-1.25; p = 0.013) groups. When DCAJs were classified as optimal, suboptimal, or inadequate, the difference between techniques had limited clinical impact (p = 0.085). However, the hemostasis time at the puncture site was significantly better with WT (no delay in 82% of patients) compared to ST (no delay in 50% of patients; p < 0.001). Conversely, ST achieved optimal and suboptimal extracorporeal lengths significantly more frequently than WT (100% vs. 66%; p < 0.001); (4) Conclusions: ECG guidance technologies achieved significantly different tip placements, but the difference had minimal clinical impact. Nevertheless, each technique displayed an important drawback at the PICC insertion point: the extracorporeal catheter was significantly longer with WT and the hemostasis delay was significantly longer with ST.


Assuntos
Cateterismo Venoso Central , Cateteres Venosos Centrais , Humanos , Cateterismo Venoso Central/métodos , Radiografia , Punções , Eletrocardiografia
13.
14.
Phys Med Biol ; 69(4)2024 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-38347732

RESUMO

Objective. Chest x-ray image representation and learning is an important problem in computer-aided diagnostic area. Existing methods usually adopt CNN or Transformers for feature representation learning and focus on learning effective representations for chest x-ray images. Although good performance can be obtained, however, these works are still limited mainly due to the ignorance of mining the correlations of channels and pay little attention on the local context-aware feature representation of chest x-ray image.Approach. To address these problems, in this paper, we propose a novel spatial-channel high-order attention model (SCHA) for chest x-ray image representation and diagnosis. The proposed network architecture mainly contains three modules, i.e. CEBN, SHAM and CHAM. To be specific, firstly, we introduce a context-enhanced backbone network by employing multi-head self-attention to extract initial features for the input chest x-ray images. Then, we develop a novel SCHA which contains both spatial and channel high-order attention learning branches. For the spatial branch, we develop a novel local biased self-attention mechanism which can capture both local and long-range global dependences of positions to learn rich context-aware representation. For the channel branch, we employ Brownian Distance Covariance to encode the correlation information of channels and regard it as the image representation. Finally, the two learning branches are integrated together for the final multi-label diagnosis classification and prediction.Main results. Experiments on the commonly used datasets including ChestX-ray14 and CheXpert demonstrate that our proposed SCHA approach can obtain better performance when comparing many related approaches.Significance. This study obtains a more discriminative method for chest x-ray classification and provides a technique for computer-aided diagnosis.


Assuntos
Diagnóstico por Computador , Tórax , Raios X , Radiografia
15.
Phys Med ; 118: 103295, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38308945

RESUMO

PURPOSE: In CyberKnife® respiratory tracking, tumor positions are predicted from external marker positions using correlation models. With available models, prediction accuracy may deteriorate when respiratory motion baseline drifts occur. Previous investigations have demonstrated that for linear models this can be mitigated by adding a time-dependent term. In this study, we have focused on added value of time-dependent terms for the available non-linear correlation models, and on phase shifts between internal and external motion tracks. METHODS: Treatment simulations for tracking with and without time-dependent terms were performed using computer generated respiratory motion tracks for 60.000 patients with variable baseline drifts and phase shifts. The protocol for acquisition of X-ray images was always the same. Tumor position prediction accuracies in simulated treatments were largely based on cumulative error-time histograms and quantified with R95: in 95% of time the prediction error is < R95 mm. RESULTS: For all available correlation models, prediction accuracy improved by adding a time-dependent term in case of occurring baseline drifts, with and without phase shifts present. For the most accurate model and 150 s between model updates, adding time dependency reduced R95 from 3.9 to 3.1 mm and from 5.4 to 3.3 mm for 0.25 and 0.50 mm/min drift, respectively. Tumor position prediction accuracy improvements with time-dependent models were obtained without increases in X-ray imaging. CONCLUSIONS: Using available correlation models with an added time-dependent term could largely mitigate negative impact of respiratory motion baseline drifts on tumor position prediction accuracy, also in case of large phase shifts.


Assuntos
Neoplasias Pulmonares , Neoplasias , Humanos , Movimento (Física) , Radiografia , Respiração , Movimento , Neoplasias Pulmonares/diagnóstico por imagem
17.
Semin Musculoskelet Radiol ; 28(1): 3-13, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38330966

RESUMO

The integration of biomarkers into medical practice has revolutionized the field of radiology, allowing for enhanced diagnostic accuracy, personalized treatment strategies, and improved patient care outcomes. This review offers radiologists a comprehensive understanding of the diverse applications of biomarkers in medicine. By elucidating the fundamental concepts, challenges, and recent advancements in biomarker utilization, it will serve as a bridge between the disciplines of radiology and epidemiology. Through an exploration of various biomarker types, such as imaging biomarkers, molecular biomarkers, and genetic markers, I outline their roles in disease detection, prognosis prediction, and therapeutic monitoring. I also discuss the significance of robust study designs, blinding, power and sample size calculations, performance metrics, and statistical methodologies in biomarker research. By fostering collaboration between radiologists, statisticians, and epidemiologists, I hope to accelerate the translation of biomarker discoveries into clinical practice, ultimately leading to improved patient care.


Assuntos
Diagnóstico por Imagem , Radiologia , Humanos , Biomarcadores , Radiografia , Diagnóstico por Imagem/métodos , Radiologia/métodos , Assistência ao Paciente
18.
Semin Musculoskelet Radiol ; 28(1): 14-25, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38330967

RESUMO

Currently no disease-modifying osteoarthritis drug has been approved for the treatment of osteoarthritis (OA) that can reverse, hold, or slow the progression of structural damage of OA-affected joints. The reasons for failure are manifold and include the heterogeneity of structural disease of the OA joint at trial inclusion, and the sensitivity of biomarkers used to measure a potential treatment effect.This article discusses the role and potential of different imaging biomarkers in OA research. We review the current role of radiography, as well as advances in quantitative three-dimensional morphological cartilage assessment and semiquantitative whole-organ assessment of OA. Although magnetic resonance imaging has evolved as the leading imaging method in OA research, recent developments in computed tomography are also discussed briefly. Finally, we address the experience from the Foundation for the National Institutes of Health Biomarker Consortium biomarker qualification study and the future role of artificial intelligence.


Assuntos
Cartilagem Articular , Osteoartrite , Humanos , Inteligência Artificial , Osteoartrite/diagnóstico por imagem , Radiografia , Imageamento por Ressonância Magnética/métodos , Biomarcadores , Cartilagem Articular/diagnóstico por imagem , Cartilagem Articular/patologia
19.
Semin Musculoskelet Radiol ; 28(1): 103-104, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38330974

RESUMO

This history page in the series "Leaders in MSK radiology" is dedicated to the memory and achievements of the German radiologist Gustav Peter Bucky who invented the Bucky diaphragm grids. He wanted to become an engineer but bowed to his parents' wishes and went to medical school. By using his technical skills, he made revolutionary contributions to the early X-ray technique.


Assuntos
Radiologia , Masculino , Humanos , Radiografia , Proteínas Adaptadoras de Transdução de Sinal
20.
BMC Musculoskelet Disord ; 25(1): 124, 2024 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-38336653

RESUMO

BACKGROUND: In metaphyseo-diaphyseal (M-D) mismatched Dorr A femurs, it is difficult to achieve proper fixation with a type 1 stem. Proper interpretation of the geometry of the femur is integral at the preoperative stage in an M-D mismatched femur, but there has been a scarcity of studies on the radiologic indices. Therefore, we analyze the previous radiologic indices and suggest the novel ones for M-D mismatched femurs. METHODS: Our study was a retrospective review of preoperative radiographs of patients who underwent total hip arthroplasty with the smallest type 1 stem or with type 3 C stem at a single institution from July 2014 to March 2022. A Type 3 C stem was used when the smallest type 1 stem failed to achieve metaphyseal fixation. One hundred twenty-six patients were categorized into two main groups. Canal-flare index, canal-calcar ratio, modified morphological cortical index, and two novel indices (lesser trochanter-to-distal ratio-α and -ß [LDR-α and -ß]) were assessed on preoperative pelvic radiographs. RESULTS: Multivariate and ROC analysis demonstrated that high LDR-ß (Exp[B]: 485.51, CI: 36.67-6427.97, p < 0.001) was associated with a more mismatched tendency group and had clinically acceptable discriminatory power (AUC: 0.765, CI: 0.675-0.855, p < 0.001) between the two cohorts. CONCLUSION: Correct assessment of preoperative femoral morphology would be fundamental in the selection of a suitable stem. The ratio based on 3 cm below the lesser trochanter of the femur seemed crucial. We recommend evaluating the newly described radiological index preoperatively in M-D mismatched Dorr A femur for planning precisely and selecting a proper stem.


Assuntos
Artroplastia de Quadril , Prótese de Quadril , Humanos , Fêmur/diagnóstico por imagem , Fêmur/cirurgia , Fêmur/anatomia & histologia , Extremidade Inferior/cirurgia , Radiografia , Estudos Retrospectivos , Desenho de Prótese
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