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1.
Medicine (Baltimore) ; 99(40): e22460, 2020 Oct 02.
Artículo en Inglés | MEDLINE | ID: mdl-33019435

RESUMEN

In scaphoid nonunion, pseudarthrosis and sclerotic change occur at the nonunion site. These changes make a distal fragment look like a trapezium on plain radiographs and we called this phenomenon the double trapezia sign. The purpose of this study was to estimate the diagnostic reliability of the double trapezia sign and its clinical and prognostic implications for the scaphoid nonunion.A retrospective review of 124 patients who underwent surgical treatment because of scaphoid nonunion between January 2007 and December 2017 was performed. Two hand surgeons and 1 musculoskeletal radiologist reviewed preoperative plain radiographs independently. Each observer evaluated the plain radiographs in 2 separate sessions at least 3 weeks apart to assess intraobserver and interobserver reliabilities of the double trapezia sign. To assess clinical and prognostic implications of the double trapezia sign, the patients were divided into the positive and nonpositive groups, and several variables such as age, sex, duration of nonunion, size of the distal fragment, avascular necrosis (AVN) of the proximal fragment, type of bone graft, healing time, and failure rate were compared between the 2 groups.The kappa values of intraobserver and interobserver reliabilities were >0.8, corresponding to almost perfect agreement. There were 58 patients in the positive group and 66 patients in the nonpositive group. The mean duration of nonunion was 38.5 months in the positive group and 12.2 months in the nonpositive group (P < .001). The size of distal fragment was 49.6% and 60.9%, respectively (P < .001). The AVN of proximal fragment was 24.1% and 54.5%, respectively (P = .001). The mean healing time was 4.1 and 6.4 months, respectively (P < .001). The failure rate was 13.8% and 27.3%, respectively (P = .066).In conclusion, the double trapezia sign is a valuable radiographic sign of scaphoid nonunion. The double trapezia sign is easily identifiable on plain radiographs and has excellent intra- and interobserver reliabilities. The positive double trapezia sign implies mid-waist nonunion, long duration of nonunion, less possibility of AVN, and favorable postoperative prognosis.


Asunto(s)
Hueso Escafoides/lesiones , Adulto , Estudios de Casos y Controles , Femenino , Fracturas no Consolidadas/diagnóstico por imagen , Fracturas no Consolidadas/patología , Humanos , Masculino , Persona de Mediana Edad , Variaciones Dependientes del Observador , Radiografía , Estudios Retrospectivos , Hueso Escafoides/diagnóstico por imagen , Hueso Escafoides/patología
2.
J Comput Assist Tomogr ; 44(5): 673-680, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32936576

RESUMEN

OBJECTIVES: This study aimed to evaluate the image quality of 7 iterative reconstruction (IR) algorithms in comparison to filtered back-projection (FBP) algorithm. METHODS: An anthropomorphic chest phantom was scanned on 4 computed tomography scanners and reconstructed with FBP and IR algorithms. Image quality of anatomical details-large/medium-sized pulmonary vessels, small pulmonary vessels, thoracic wall, and small and large lesions-was scored. Furthermore, general impression of noise, image contrast, and artifacts were evaluated. Visual grading regression was used to analyze the data. Standard deviations were measured, and the noise power spectrum was calculated. RESULTS: Iterative reconstruction algorithms showed significantly better results when compared with FBP for these criteria (regression coefficients/P values in parentheses): vessels (FIRST: -1.8/0.05, AIDR Enhanced: <-2.3/0.01, Veo: <-0.1/0.03, ADMIRE: <-2.1/0.04), lesions (FIRST: <-2.6/0.01, AIDR Enhanced: <-1.9/0.03, IMR1: <-2.7/0.01, Veo: <-2.4/0.02, ADMIRE: -2.3/0.02), image noise (FIRST: <-3.2/0.004, AIDR Enhanced: <-3.5/0.002, IMR1: <-6.1/0.001, iDose: <-2.3/0.02, Veo: <-3.4/0.002, ADMIRE: <-3.5/0.02), image contrast (FIRST: -2.3/0.01, AIDR Enhanced: -2.5/0.01, IMR1: -3.7/0.001, iDose: -2.1/0.02), and artifacts (FIRST: <-3.8/0.004, AIDR Enhanced: <-2.7/0.02, IMR1: <-2.6/0.02, iDose: -2.1/0.04, Veo: -2.6/0.02). The iDose algorithm was the only IR algorithm that maintained the noise frequencies. CONCLUSIONS: Iterative reconstruction algorithms performed differently on all evaluated criteria, showing the importance of careful implementation of algorithms for diagnostic purposes.


Asunto(s)
Procesamiento de Imagen Asistido por Computador/métodos , Fantasmas de Imagen , Radiografía Torácica/métodos , Tomografía Computarizada por Rayos X/métodos , Algoritmos , Artefactos , Variaciones Dependientes del Observador , Reproducibilidad de los Resultados , Relación Señal-Ruido
3.
Ther Adv Cardiovasc Dis ; 14: 1753944720958982, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32993464

RESUMEN

AIM: To evaluate inter-core laboratory variability of quantitative coronary angiography (QCA) parameters in comparison with intra-core laboratory variability in a randomized controlled trial evaluating drug-eluting stents. METHODS: A total of 50 patients with 62 coronary lesions were analyzed by four analysis experts belonging to an Angiographic Core Laboratory (ACL: 1 expert) and a Cardiovascular Imaging Core Laboratory (CICL: 3 experts). QCA was based on the same standard operating procedure, but selections of projection and cine frames were at the discretion of each analyst. Inter- and intra-core laboratory variabilities were evaluated by accuracy, precision, Bland Altman analysis, and coefficient of variation. RESULTS: Pre-MLD (minimal lumen diameter) was significantly smaller in results from ACL than those from all CICL experts. Number of analyzed projections did not affect pre-MLD results. Acute gain was larger in ACL than in CICL2. No significant difference was observed in late loss and loss index between inter-core laboratories. Agreement between core labs in the Bland-Altman analysis for each QCA parameter was as follows (mean difference, 95% limits of agreement): pre-MLD (-0.32, -0.74 to 0.10), stent MLD (0.08, -0.28 to 0.44), acute gain (0.22, -0.44 to 0.88), and late loss (-0.07, -0.69 to 0.55). Agreement between analysts in CICL (mean difference, 95% limits of agreement) was: pre MLD (-0.03, -0.37 to 0.31), stent MLD (0.15, -0.15 to 0.45), acute gain (0.05, -0.45 to 0.55), and late loss (0.04, -0.52 to 0.60). The widest limits of agreement among three analyses were shown in both analyses. Width of limited agreement in the intra-core laboratory analysis tended to be smaller than the inter-core laboratory analysis with these parameters. Coefficient of variation tended to be larger in lesion length (LL), acute gain, late loss, and loss index in inter- and in intra- core laboratory comparisons. CONCLUSION: Inter-core laboratory QCA variability in late loss and loss index analysis could be similar to intra-core laboratory variability, but more strict alignment between core laboratories would be necessary for initial procedural data analysis.


Asunto(s)
Cineangiografía , Angiografía Coronaria , Enfermedad de la Arteria Coronaria/diagnóstico por imagen , Enfermedad de la Arteria Coronaria/terapia , Vasos Coronarios/diagnóstico por imagen , Stents Liberadores de Fármacos , Intervención Coronaria Percutánea/instrumentación , Anciano , Femenino , Humanos , Japón , Masculino , Persona de Mediana Edad , Variaciones Dependientes del Observador , Intervención Coronaria Percutánea/efectos adversos , Valor Predictivo de las Pruebas , Reproducibilidad de los Resultados , Factores de Tiempo , Resultado del Tratamiento
4.
Zhonghua Kou Qiang Yi Xue Za Zhi ; 55(9): 654-660, 2020 Sep 09.
Artículo en Chino | MEDLINE | ID: mdl-32878401

RESUMEN

Objective: To establish and to evaluate a computer-aided system based on deep-learning for detection and diagnosis of dental approximal caries on periapical radiographs. Methods: One hundred and sixty human premolars and molars extracted for orthodontic or periodontal reasons were obtained from Department of Oral and Maxillofacial Surgery, Affiliated Stomatological Hospital, Fujian Medical University. A total of 160 periapical radiographic images were divided into a training dataset (n=80) and a test dataset (n=80). A deep-learning based computer-aided caries diagnosis system was established and trained. The performances of computer-aided diagnosis system and human observer were compared using receiver operating characteristic (ROC) curves, precision-recall (P-R) curves, the area under the curve (AUC), sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV). The AUC values of human observers and caries diagnosis system was compared by using an online statistical tool (SPSSAU 20.0). Chi-square test was used to analyze the differences between human observers and caries diagnosis system (ɑ=0.05). Results: The AUC values of human observers and caries diagnosis system were 0.729 (95%CI: 0.650-0.808) and 0.762 (95%CI: 0.685-0.839), respectively (P>0.05). No significant differences were found for the specificity, PPV and NPV between the caries diagnosis system and human observers (P all>0.05). The caries diagnosis system was significantly more sensitive in detecting dental proximal caries than human observers (P<0.05). For the diagnosis of level-1 caries (caries limited to outer 1/2 of enamel), the sensitivity of human observers and computer-aided detection system were 27% and 77%, respectively (P<0.05). Conclusions: The computer-aided diagnosis system provided similar accuracy as human observers and significantly better sensitivity than human observers, especially for shallow caries in enamel.


Asunto(s)
Caries Dental/diagnóstico , Radiografía Dental Digital , Área Bajo la Curva , Esmalte Dental , Humanos , Variaciones Dependientes del Observador , Curva ROC , Sensibilidad y Especificidad
6.
Br J Radiol ; 93(1114): 20200543, 2020 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-32877210

RESUMEN

OBJECTIVES: To evaluate interobserver agreement for T2 weighted (T2W) and diffusion-weighted MRI (DW-MRI) contours of locally advanced rectal cancer (LARC); and to evaluate manual and semi-automated delineations of restricted diffusion tumour subvolumes. METHODS: 20 cases of LARC were reviewed by 2 radiation oncologists and 2 radiologists. Contours of gross tumour volume (GTV) on T2W, DW-MRI and co-registered T2W/DW-MRI were independently delineated and compared using Dice Similarity Coefficient (DSC), mean distance to agreement (MDA) and other metrics of interobserver agreement. Restricted diffusion subvolumes within GTVs were manually delineated and compared to semi-automatically generated contours corresponding to intratumoral apparent diffusion coefficient (ADC) centile values. RESULTS: Observers were able to delineate subvolumes of restricted diffusion with moderate agreement (DSC 0.666, MDA 1.92 mm). Semi-automated segmentation based on the 40th centile intratumoral ADC value demonstrated moderate average agreement with consensus delineations (DSC 0.581, MDA 2.44 mm), with errors noted in image registration and luminal variation between acquisitions. A small validation set of four cases with optimised planning MRI demonstrated improvement (DSC 0.669, MDA 1.91 mm). CONCLUSION: Contours based on co-registered T2W and DW-MRI could be used for delineation of biologically relevant tumour subvolumes. Semi-automated delineation based on patient-specific intratumoral ADC thresholds may standardise subvolume delineation if registration between acquisitions is sufficiently accurate. ADVANCES IN KNOWLEDGE: This is the first study to evaluate the feasibility of semi-automated diffusion-based subvolume delineation in LARC. This approach could be applied to dose escalation or 'dose painting' protocols to improve delineation reproducibility.


Asunto(s)
Adenocarcinoma/diagnóstico por imagen , Imagen de Difusión por Resonancia Magnética/métodos , Interpretación de Imagen Asistida por Computador/métodos , Neoplasias del Recto/diagnóstico por imagen , Adenocarcinoma/patología , Adenocarcinoma/terapia , Adulto , Anciano , Anciano de 80 o más Años , Competencia Clínica , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estadificación de Neoplasias , Variaciones Dependientes del Observador , Neoplasias del Recto/patología , Neoplasias del Recto/terapia , Reproducibilidad de los Resultados , Estudios Retrospectivos , Carga Tumoral
7.
West J Emerg Med ; 21(5): 1067-1075, 2020 Aug 17.
Artículo en Inglés | MEDLINE | ID: mdl-32970556

RESUMEN

INTRODUCTION: Pulmonary opacities in COVID-19 increase throughout the illness and peak after ten days. The radiological literature mainly focuses on CT findings. The purpose of this study was to assess the diagnostic and prognostic value of chest radiographs (CXR) for coronavirus disease 2019 (COVID-19) at presentation. METHODS: We retrospectively identified consecutive reverse transcription polymerase reaction-confirmed COVID-19 patients (n = 104, 75% men) and patients (n = 75, 51% men) with repeated negative severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) tests. Two radiologists blindly and independently reviewed the CXRs, documented findings, assigned radiographic assessment of lung edema (RALE) scores, and predicted the patients' COVID-19 status. We calculated interobserver reliability. The score use for diagnosis and prognosis of COVID-19 was evaluated with the area under the receiver operating characteristic curve. RESULTS: The overall RALE score failed to identify COVID-19 patients at presentation. However, the score was inversely correlated with a COVID-19 diagnosis within ≤2 days, and a positive correlation was found six days after symptom onset.Interobserver agreement with regard to separating normal from abnormal CXRs was moderate (k = 0.408) with low specificity (25% and 27%). Definite pleural effusion had almost perfect agreement (k = 0.833) and substantially reduced the odds of a COVID-19 diagnosis. Disease distribution and experts' opinion on COVID-19 status had only fair interobserver agreement. The RALE score interobserver reliability was moderate to good (intraclass correlation coefficient = 0.745). A high RALE score predicted a poor outcome (intensive care unit hospitalization, intubation, or death) in COVID-19 patients; a score of ≥5 substantially increased the odds of having a poor outcome. CONCLUSION: Chest radiography was found not to be a valid diagnostic tool for COVID-19, as normal or near-normal CXRs are more likely early in the disease course. Pleural effusions at presentation suggest a diagnosis other than COVID-19. More extensive lung opacities at presentation are associated with poor outcome in COVID-19 patients. Thus, patients with more than minimal opacities should be monitored closely for clinical deterioration. This clinical application of CXR is its greatest strength in COVID-19 as it impacts patient care.


Asunto(s)
Betacoronavirus , Reglas de Decisión Clínica , Técnicas de Laboratorio Clínico/métodos , Infecciones por Coronavirus/diagnóstico por imagen , Pulmón/diagnóstico por imagen , Neumonía Viral/diagnóstico por imagen , Adulto , Anciano , Anciano de 80 o más Años , Área Bajo la Curva , Betacoronavirus/aislamiento & purificación , Estudios de Casos y Controles , Infecciones por Coronavirus/diagnóstico , Femenino , Humanos , Masculino , Persona de Mediana Edad , Variaciones Dependientes del Observador , Pandemias , Pronóstico , Curva ROC , Radiografía Torácica , Reproducibilidad de los Resultados , Estudios Retrospectivos , Método Simple Ciego
8.
Arch Cardiovasc Dis ; 113(8-9): 542-550, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32771348

RESUMEN

BACKGROUND: Screening for Fabry disease is sub-optimal in non-specialised centres. AIM: To assess the diagnostic value of electrocardiographic scores of left ventricular hypertrophy and a combined electrocardiographic and echocardiographic model in Fabry disease. METHODS: We retrospectively reviewed the electrocardiograms and echocardiograms of 61 patients (mean age 55.6±11.5 years; 57% men) with Fabry disease and left ventricular hypertrophy, and compared them with those from 59 patients (mean age 44.8±18.3 years; 66% men) with sarcomeric hypertrophic cardiomyopathy. Six electrocardiography criteria for left ventricular hypertrophy were specifically analysed: Sokolow-Lyon voltage index; Cornell voltage index; Gubner index; Romhilt-Estes score; Sokolow-Lyon product (voltage index×QRS duration); and Cornell product (voltage index×QRS duration). RESULTS: Right bundle branch block was more frequent in patients with Fabry disease (54% vs. 22%; P=0.001). QRS duration, Gubner score and Sokolow-Lyon product were significantly higher in patients with Fabry disease. Maximal wall thickness was higher in patients with sarcomeric hypertrophic cardiomyopathy (21.9±5.1 vs. 15.5±2.9mm; P<0.001). Indexed sinus of Valsalva diameter was larger in patients with Fabry disease. After multivariable analysis, right bundle branch block, Sokolow-Lyon product, maximal wall thickness and aortic diameter were independently associated with Fabry disease. A model including these four variables yielded an area under the receiver operating characteristic curve of 0.918 (95% confidence interval 0.868-0.968) for Fabry disease. CONCLUSION: Our model combining easy-to-assess electrocardiographic and echocardiographic variables may be helpful in improving screening and reducing diagnosis delay in Fabry disease.


Asunto(s)
Cardiomiopatía Hipertrófica/diagnóstico , Ecocardiografía , Electrocardiografía , Enfermedad de Fabry/diagnóstico , Adulto , Anciano , Cardiomiopatía Hipertrófica/diagnóstico por imagen , Cardiomiopatía Hipertrófica/fisiopatología , Diagnóstico Diferencial , Enfermedad de Fabry/diagnóstico por imagen , Enfermedad de Fabry/fisiopatología , Femenino , Frecuencia Cardíaca , Humanos , Masculino , Persona de Mediana Edad , Variaciones Dependientes del Observador , Valor Predictivo de las Pruebas , Reproducibilidad de los Resultados , Estudios Retrospectivos , Volumen Sistólico , Función Ventricular Izquierda , Función Ventricular Derecha , Remodelación Ventricular
10.
J Comput Assist Tomogr ; 44(5): 759-765, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32842061

RESUMEN

OBJECTIVE: To compare the intravoxel incoherent motion (IVIM) parameters of rectal tumors before and after lumen distension obtained with sonography transmission gel. METHODS: Twenty-five patients were enrolled. The multiple b values of IVIM including 0, 20, 50, 100, 150, 200, 400, 600, 800, 1000, 1500, and 2000 s/mm. Two blinded readers have drawn the region of interests and calculated the D, D*, and f values. Interobserver variability between the 2 readers was measured by intraclass correlation coefficients and Altman-Bland plots. The intergroup differences of the average values were compared with the paired sample t test. RESULTS: After distention, the interrater agreement of the D* value increased obviously (from 0.547 to 0.692) and that of the D and f values increased slightly (from 0.731 and 0.618 to 0.807 and 0.666). The difference in the D value had statistical significance (P = 0.0043). CONCLUSIONS: Intraluminal distension can increase the repeatability of IVIM parameters and the value of IVIM.


Asunto(s)
Imagen de Difusión por Resonancia Magnética/métodos , Geles/uso terapéutico , Neoplasias del Recto/diagnóstico por imagen , Recto/diagnóstico por imagen , Adulto , Medios de Contraste , Femenino , Humanos , Interpretación de Imagen Asistida por Computador , Masculino , Persona de Mediana Edad , Movimiento/fisiología , Variaciones Dependientes del Observador , Neoplasias del Recto/fisiopatología , Recto/fisiopatología , Ultrasonografía
11.
Bone Joint J ; 102-B(8): 1041-1047, 2020 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-32731824

RESUMEN

AIMS: The Wrightington classification system of fracture-dislocations of the elbow divides these injuries into six subtypes depending on the involvement of the coronoid and the radial head. The aim of this study was to assess the reliability and reproducibility of this classification system. METHODS: This was a blinded study using radiographs and CT scans of 48 consecutive patients managed according to the Wrightington classification system between 2010 and 2018. Four trauma and orthopaedic consultants, two post CCT fellows, and one speciality registrar based in the UK classified the injuries. The seven observers reviewed preoperative radiographs and CT scans twice, with a minimum four-week interval. Radiographs and CT scans were reviewed separately. Inter- and intraobserver reliability were calculated using Fleiss and Cohen kappa coefficients. The Landis and Koch criteria were used to interpret the strength of the kappa values. Validity was assessed by calculating the percentage agreement against intraoperative findings. RESULTS: Of the 48 patients, three (6%) had type A injury, 11 (23%) type B, 16 (33%) type B+, 16 (33%) Type C, two (4%) type D+, and none had a type D injury. All 48 patients had anteroposterior (AP) and lateral radiographs, 44 had 2D CT scans, and 39 had 3D reconstructions. The interobserver reliability kappa value was 0.52 for radiographs, 0.71 for 2D CT scans, and 0.73 for a combination of 2D and 3D reconstruction CT scans. The median intraobserver reliability was 0.75 (interquartile range (IQR) 0.62 to 0.79) for radiographs, 0.77 (IQR 0.73 to 0.94) for 2D CT scans, and 0.89 (IQR 0.77 to 0.93) for the combination of 2D and 3D reconstruction. Validity analysis showed that accuracy significantly improved when using CT scans (p = 0.018 and p = 0.028 respectively). CONCLUSION: The Wrightington classification system is a reliable and valid method of classifying fracture-dislocations of the elbow. CT scans are significantly more accurate than radiographs when identifying the pattern of injury, with good intra- and interobserver reproducibility. Cite this article: Bone Joint J 2020;102-B(8):1041-1047.


Asunto(s)
Articulación del Codo/diagnóstico por imagen , Articulación del Codo/lesiones , Fractura-Luxación/clasificación , Imagenología Tridimensional , Tomografía Computarizada por Rayos X/métodos , Adolescente , Adulto , Estudios de Cohortes , Femenino , Fractura-Luxación/diagnóstico por imagen , Fracturas Óseas/clasificación , Fracturas Óseas/diagnóstico por imagen , Humanos , Puntaje de Gravedad del Traumatismo , Masculino , Persona de Mediana Edad , Variaciones Dependientes del Observador , Reproducibilidad de los Resultados , Estudios Retrospectivos , Adulto Joven
12.
APMIS ; 128(11): 573-582, 2020 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-32860265

RESUMEN

Human epidermal growth factor receptor 2 (HER2) gene status and overexpression, occurring in ~ 13.6% of primary breast cancers, is essential for identifying patients likely to benefit from biological treatment. In this method of evaluation study, we tested and compared the HER2 gene-protein assay (GPA) with routine HER2 immunohistochemistry (IHC) and fluorescence in situ hybridization (FISH). The GPA was evaluated using 67 formalin-fixed paraffin-embedded (FFPE) HER2 equivoval IHC (2+) breast cancer tissue samples. Overall, agreement between GPA silver in situ hybridization (SISH) and FISH was 91.9% (57/62). Regression analysis revealed slightly higher, but non-significant difference in HER2/chromosome enumeration probe 17 (CEP17) ratio for GPA as compared to FISH (p = 0.074). Intraclass correlation coefficients (ICCs) of 0.94 and Spearman´s rank correlation coefficients of 0.93 (p < 0.0001) for FISH and GPA SISH suggested strong inter-observer association for methods with one observer counting on average 0.23 significant higher for GPA SISH (p = 0.014). Intra-observer IHC method reproducibility was 52.6% (κ = 0.3122, p = 0.004) and 79.7% (κ = 0.6428, p = 0.9197), suggesting fair significant and substantial non-significant difference between tests for reviewers. Inter-observer reproducibility for IHC methods was 53%. While inter-observer reproducibility for experienced IHC interpretation suggested significant differences (κ = 0.3636, p = 0.0332), unexperienced interpretation of IHC GPA suggested fair non-significant difference between reviewers (κ = 0.3101, p = 0.0747). Using FISH as reference, the diagnostic indices for GPA SISH were as follows: sensitivity 100%, specificity 95% and accuracy 92%. Inaccuracy between tests was in 80% of cases due to ISH categorization as equivocal by one of the methods. IHC results highlight that it may be beneficial with a method for simultaneously visualization of HER2 gene and protein status.


Asunto(s)
Neoplasias de la Mama/diagnóstico , Carcinoma/diagnóstico , Receptor ErbB-2/genética , Biomarcadores de Tumor/genética , Neoplasias de la Mama/genética , Neoplasias de la Mama/patología , Neoplasias de la Mama/cirugía , Carcinoma/genética , Carcinoma/patología , Carcinoma/cirugía , Femenino , Expresión Génica , Humanos , Inmunohistoquímica , Hibridación Fluorescente in Situ , Metástasis Linfática , Variaciones Dependientes del Observador , Análisis por Matrices de Proteínas , Reproducibilidad de los Resultados , Sensibilidad y Especificidad
13.
Eur J Vasc Endovasc Surg ; 60(3): 462-468, 2020 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-32763120

RESUMEN

OBJECTIVE: Ankle brachial index (ABI) is widely used for the diagnosis of lower extremity artery disease (LEAD). The purpose of this prospective study was to validate the diagnostic ability and reproducibility of a four cuff automated oscillometric device vs. the Doppler method. METHODS: Patients with suspected LEAD or asymptomatic individuals at risk because of the presence two or more cardiovascular risk factors were enrolled. For each patient, Doppler and oscillometric ABI measurements were repeated by two observers to address intra- and interobserver reproducibility. RESULTS: In total, 118 patients were evaluated. The prevalence of Doppler ABI (Dop-ABI) ≤ 0.90 was 45.8%. Taking the Dop-ABI as the reference, the sensitivity, specificity, accuracy, positive and negative predictive values of oscillometric ABI (Osc-ABI) during the first measurement by the first observer were 89.1%, 94.4%, 94.1%, 91.8%, and 92.4%, respectively. The concordance for diagnosing ABI ≤0.90 between methods was excellent (kappa coefficients ranging from 0.80 to 0.88 with different observers). Intra-observer reproducibility assessed by intraclass correlation coefficient (ICC) between methods were 0.94 for observer 1 and 0.96 for observer 2. The intra-observer reproducibility using the same method was also excellent (ICC 0.94, 95% confidence interval [CI] 0.91-0.95) for Dop-ABI and 0.95 (95% CI 0.93-0.97) for Osc-ABI). The ICC for interobserver reproducibility using the same method was 0.95 (95% CI 0.92-0.96) for Dop-ABI and 0.96 (95% CI 0.94-0.97) for Osc-ABI. CONCLUSION: This study validates the excellent diagnostic performances of a four cuff oscillometric device specifically designed for screening for LEAD. The simple measurement method could therefore be advocated in primary care where fast, easy, and reliable methods are suitable.


Asunto(s)
Índice Tobillo Braquial/instrumentación , Extremidad Inferior/irrigación sanguínea , Oscilometría/instrumentación , Enfermedad Arterial Periférica/diagnóstico , Ultrasonografía Doppler , Anciano , Anciano de 80 o más Años , Diseño de Equipo , Femenino , Francia , Humanos , Japón , Masculino , Persona de Mediana Edad , Variaciones Dependientes del Observador , Enfermedad Arterial Periférica/diagnóstico por imagen , Enfermedad Arterial Periférica/fisiopatología , Valor Predictivo de las Pruebas , Estudios Prospectivos , Reproducibilidad de los Resultados
15.
PLoS One ; 15(8): e0238196, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32841291

RESUMEN

The need for an efficacious vaccine against highly pathogenic filoviruses was reinforced by the devastating 2014-2016 outbreak of Ebola virus (EBOV) disease (EVD) in Guinea, Sierra Leone, and Liberia that resulted in over 28,000 cases and over 11,300 deaths. In addition, the 2018-2020 outbreak in the Democratic Republic of the Congo currently has over 3,400 cases and over 2,200 deaths. A fully licensed vaccine and at least one other investigational vaccine are being deployed to combat this EVD outbreak. To support vaccine development and pre-clinical/clinical testing a Filovirus Animal Nonclinical Group (FANG) human anti-EBOV GP IgG ELISA was developed to measure anti-EBOV GP IgG antibodies. This ELISA is currently being used in multiple laboratories. Reported here is a characterization of an interlaboratory statistical analysis of the human anti-EBOV GP IgG ELISA as part of a collaborative study between five participating laboratories. Each laboratory used similar method protocols and reagents to measure anti-EBOV GP IgG levels in human serum samples from a proficiency panel consisting of ten serum samples created by the differential dilution of a serum sample positive for anti-GP IgG antibodies (BMIZAIRE105) with negative serum (BMI529). The total assay variability (inter- and intra-assay variability) %CVs observed at each laboratory ranged from 12.2 to 30.6. Intermediate precision (inter-assay variability) for the laboratory runs ranged from 8.9 to 21.7%CV and repeatability (intra-assay variability) %CVs ranged from 7.2 to 23.7. The estimated slope for the relationship between log10(Target Concentration) and the log10(Observed Concentration) across all five laboratories was 0.95 with a 90% confidence interval of (0.93, 0.97). Equivalence test results showed that the 90% confidence interval for the ratios for the sample-specific mean concentrations at the five individual labs to the overall laboratory consensus value were within the equivalence bounds of 0.80 to 1.25 for each laboratory and test sample, except for six test samples from Lab D, two samples from Lab B1, and one sample from Lab B2. The mean laboratory concentrations for Lab D were less than those from the other laboratories by 20% on average across the serum samples. The evaluation of the proficiency panel at these laboratories provides a limited assessment of assay precision (intermediate precision, repeatability, and total assay variability), dilutional linearity, and accuracy. This evaluation suggests that the within-laboratory performance of the anti-EBOV GP IgG ELISA as implemented at the five laboratories is consistent with the intended use of the assay based on the acceptance criteria used by laboratories that have validated the assay. However, the assessment of between-laboratory performance revealed lower observed concentrations at Lab D and greater variability in assay results at Lab B1 relative to other laboratories.


Asunto(s)
Anticuerpos Antivirales/sangre , Ebolavirus/inmunología , Ensayo de Inmunoadsorción Enzimática/normas , Fiebre Hemorrágica Ebola/inmunología , Proteínas Virales/inmunología , África Occidental/epidemiología , Animales , República Democrática del Congo/epidemiología , Brotes de Enfermedades , Vacunas contra el Virus del Ébola/inmunología , Vacunas contra el Virus del Ébola/aislamiento & purificación , Ensayo de Inmunoadsorción Enzimática/estadística & datos numéricos , Fiebre Hemorrágica Ebola/epidemiología , Fiebre Hemorrágica Ebola/prevención & control , Humanos , Inmunoglobulina G/sangre , Laboratorios , Variaciones Dependientes del Observador
16.
Braz Oral Res ; 34: e082, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32785477

RESUMEN

This study aims to assess the influence of high-density material on the radiographic diagnosis of proximal caries in digital systems with automatic exposure compensation, and to evaluate the effect of subjective adjustment of brightness and contrast to undertake this diagnostic task. Twenty bitewing radiographs of forty posterior human teeth with non-cavitated carious lesions, confirmed by micro-CT, were obtained with two digital systems. A porcelain-fused-to-metal crown attached to a titanium implant was inserted into the exposed area, and all the radiographs were repeated. Five radiologists assessed the radiographs and diagnosed proximal carious lesions. Afterwards, the observers were asked to adjust image brightness and contrast, based on their subjective perception, and to reassess the images. Thirty percent of each experimental group was reassessed to test intraobserver reproducibility, totaling 208 images per observer. Intraobserver and interobserver agreements ranged from fair to substantial. Sensitivity, specificity, predictive values, and area under the ROC curve were calculated and compared for each radiographic system, using ANOVA (α = 0.05). Overall, presence of high-density material and adjustment of brightness and contrast did not significantly influence the radiographic diagnosis of proximal caries (p ≥ 0.05). Regarding Digora Optime, adjustment of brightness and contrast significantly increased (p < 0.05) the diagnostic accuracy of proximal carious lesions in the presence of high-density material. In conclusion, the presence of high-density material in the X-rayed region does not influence radiographic diagnosis of proximal caries. However, when it is present in the X-rayed area, subjective adjustment of brightness and contrast is recommended for use with the Digora Optime digital system.


Asunto(s)
Caries Dental , Radiografía Dental Digital , Humanos , Variaciones Dependientes del Observador , Curva ROC , Intensificación de Imagen Radiográfica , Reproducibilidad de los Resultados
17.
PLoS One ; 15(8): e0237352, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32797085

RESUMEN

PURPOSE: To analyze the individual value and the contribution of color fundus photography (CFP) and optical coherence tomography (OCT) in the screening of age-related macular degeneration (AMD) of an unselected population. METHODS: CFP and OCT images of 15957 eyes of 8069 subjects older than 55 years, obtained during a population-based screening for AMD using a single diagnostic non-mydriatic imaging device, were analyzed by a blinded examiner. The two techniques were preliminary evaluated considering the dichotomous parameter "gradable/ungradable", then gradable images were classified. CFP were graded according to the standardized classification of AMD lesions. OCT images were also categorized considering the presence of signs of early/intermediate AMD, late AMD, or other retinal diseases. Another blinded operator re-graded 1978 randomly selected images (for both CFP and OCT), to assess test reproducibility. RESULTS: Of the 15957 eyes, 8356 CFP (52.4%) and 15594 (97.7%) OCT scans were gradable. Moreover, most of the eyes with ungradable CFP (7339, 96.6%) were gradable at OCT. AMD signs were revealed in 7.4% of gradable CFP and in 10.4% of gradable OCT images. Moreover, at OCT, AMD signs were found in 1110 (6.9%) eyes whose CFP were ungradable or without AMD (847 and 263 eyes, respectively). The inter-operator agreement was good for the gradable versus ungradable parameter, and optimal for the AMD grading parameter of CFP. The agreement was optimal for all OCT parameters. CONCLUSIONS: OCT provided gradable images in almost all examined eyes, compared to limited CFP efficiency. Moreover, OCT images allowed to detect more AMD eyes compared to gradable photos. OCT imaging appears to significantly improve the power of AMD screening in a general, unselected population, compared to CFP alone.


Asunto(s)
Fondo de Ojo , Degeneración Macular/diagnóstico , Tamizaje Masivo/estadística & datos numéricos , Fotograbar/estadística & datos numéricos , Tomografía de Coherencia Óptica/estadística & datos numéricos , Humanos , Tamizaje Masivo/métodos , Persona de Mediana Edad , Variaciones Dependientes del Observador , Reproducibilidad de los Resultados , Estudios Retrospectivos
18.
Br J Radiol ; 93(1113): 20200552, 2020 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-32614611

RESUMEN

OBJECTIVE: T2 blackout (TBO) effect, which is a common finding in the brains of multiple sclerosis (MS) patients and older population that are imaged for other reasons on diffusion weighted imagings (DWI) and apparent diffusion coefficient (ADC) map show the existence of paramagnetic materials in the tissue. Because iron is known to accumulate in especially deep gray matter (DGM) structures in MS brains, we aimed to investigate the relationship between TBO and clinico-radiological parameters that may be iron-related in MS. METHODS: We retrospectively reviewed the latest MR images of MS patients on 3 Tesla MR scanner between 2018 and 2019. TBO existence and severity on DWI-ADC was assessed by two radiologists and its correlation with several outcomes of MS was investigated. RESULTS: No significant relationship was found between TBO and gender, subtype of MS whereas TBO was positively correlated with parameters such as black-hole lesions, cortical atrophy, duration of disease, age and extended disability status scale (EDSS) score. CONCLUSIONS: TBO shows correlation with the conditions which were revealed to be associated with iron accumulation in the brain of MS patients in the literature. Therefore, we concluded that TBO and its severity in DGM may represent iron accumulation in MS brains. ADVANCES IN KNOWLEDGE: TBO effect as a frequent imaging finding in daily practice may be used as predictor of the disease course of MS due to possible effects of iron accumulation in brain and thereby may be useful in modifying treatment strategies.


Asunto(s)
Encéfalo/diagnóstico por imagen , Encéfalo/metabolismo , Imagen de Difusión por Resonancia Magnética/métodos , Hierro/metabolismo , Esclerosis Múltiple/diagnóstico por imagen , Adulto , Femenino , Humanos , Masculino , Persona de Mediana Edad , Esclerosis Múltiple/metabolismo , Variaciones Dependientes del Observador , Estudios Retrospectivos , Estadísticas no Paramétricas , Adulto Joven
19.
Am J Physiol Heart Circ Physiol ; 319(2): H360-H369, 2020 08 01.
Artículo en Inglés | MEDLINE | ID: mdl-32678708

RESUMEN

Proper inlet boundary conditions are essential for accurate computational fluid dynamics (CFD) modeling. We developed methodology to derive noninvasive FFRB using CFD and computed tomography coronary angiography (CTCA) images. This study aims to assess the influence of brachial mean blood pressure (MBP) and total coronary inflow on FFRB computation. Twenty-two patients underwent both CTCA and FFR measurements. Total coronary flow was computed from left ventricular mass (LVM) measured from CTCA. A total of 286 CFD simulations were run by varying MBP and LVM at 70, 80, 90, 100, 110, 120, and 130% of the measured values. FFRB increased with incrementally higher input values of MBP: 0.78 ± 0.12, 0.80 ± 0.11, 0.82 ± 0.10, 0.84 ± 0.09, 0.85 ± 0.08, 0.86 ± 0.08, and 0.87 ± 0.07, respectively. Conversely, FFRB decreased with incrementally higher inputs value of LVM: 0.86 ± 0.08, 0.85 ± 0.08, 0.84 ± 0.09, 0.84 ± 0.09, 0.83 ± 0.10, 0.83 ± 0.10, and 0.82 ± 0.10, respectively. Noninvasive FFRB calculated using measured MBP and LVM on a total of 30 vessels was 0.84 ± 0.09 and correlated well with invasive FFR (0.83 ± 0.09) (r = 0.92, P < 0.001). Positive association was observed between FFRB and MBP input values (mmHg) and negative association between FFRB and LVM values (g). Respective slopes were 0.0016 and -0.005, respectively, suggesting potential application of FFRB in a clinical setting. Inaccurate MBP and LVM inputs differing from patient-specific values could result in misclassification of borderline ischemic lesions.NEW & NOTEWORTHY While brachial mean blood pressure (MBP) and left ventricular mass (LVM) measured from CTCA are the two CFD simulation input parameters, their effects on noninvasive fractional flow reserve (FFRB) have not been systematically investigated. We demonstrate that inaccurate MBP and LVM inputs differing from patient-specific values could result in misclassification of borderline ischemic lesions. This is important in the clinical application of noninvasive FFR in coronary artery disease diagnosis.


Asunto(s)
Presión Arterial , Arteria Braquial/fisiopatología , Angiografía por Tomografía Computarizada , Angiografía Coronaria , Enfermedad de la Arteria Coronaria/diagnóstico por imagen , Vasos Coronarios/diagnóstico por imagen , Reserva del Flujo Fraccional Miocárdico , Ventrículos Cardíacos/diagnóstico por imagen , Modelos Cardiovasculares , Tomografía Computarizada Multidetector , Modelación Específica para el Paciente , Interpretación de Imagen Radiográfica Asistida por Computador , Anciano , Enfermedad de la Arteria Coronaria/fisiopatología , Vasos Coronarios/fisiopatología , Femenino , Ventrículos Cardíacos/fisiopatología , Humanos , Hidrodinámica , Masculino , Persona de Mediana Edad , Variaciones Dependientes del Observador , Valor Predictivo de las Pruebas , Reproducibilidad de los Resultados , Estudios Retrospectivos
20.
Clin Radiol ; 75(9): 710.e9-710.e14, 2020 09.
Artículo en Inglés | MEDLINE | ID: mdl-32631626

RESUMEN

AIM: To validate the British Society of Thoracic Imaging issued guidelines for the categorisation of chest radiographs for coronavirus disease 2019 (COVID-19) reporting regarding reproducibility amongst radiologists and diagnostic performance. MATERIALS AND METHODS: Chest radiographs from 50 patients with COVID-19, and 50 control patients with symptoms consistent with COVID-19 from prior to the emergence of the novel coronavirus were assessed by seven consultant radiologists with regards to the British Society of Thoracic Imaging guidelines. RESULTS: The findings show excellent specificity (100%) and moderate sensitivity (44%) for guideline-defined Classic/Probable COVID-19, and substantial interobserver agreement (Fleiss' k=0.61). Fair agreement was observed for the "Indeterminate for COVID-19" (k=0.23), and "Non-COVID-19" (k=0.37) categories; furthermore, the sensitivity (0.26 and 0.14 respectively) and specificity (0.76, 0.80) of these categories for COVID-19 were not significantly different (McNemar's test p=0.18 and p=0.67). CONCLUSION: An amalgamation of the categories of "Indeterminate for COVID-19" and "Non-COVID-19" into a single "not classic of COVID-19" classification would improve interobserver agreement, encompass patients with a similar probability of COVID-19, and remove the possibility of labelling patients with COVID-19 as "Non-COVID-19", which is the presenting radiographic appearance in a significant minority (14%) of patients.


Asunto(s)
Betacoronavirus , Infecciones por Coronavirus/diagnóstico por imagen , Neumonía Viral/diagnóstico por imagen , Guías de Práctica Clínica como Asunto , Radiografía Torácica/métodos , Tomografía Computarizada por Rayos X/métodos , Anciano , Femenino , Humanos , Pulmón/diagnóstico por imagen , Masculino , Persona de Mediana Edad , Variaciones Dependientes del Observador , Pandemias , Reacción en Cadena de la Polimerasa , Reproducibilidad de los Resultados , Sensibilidad y Especificidad
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