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OBJECTIVES: We examined whether providing a quantitative report (QReport) of regional brain volumes improves radiologists' accuracy and confidence in detecting volume loss, and in differentiating Alzheimer's disease (AD) and frontotemporal dementia (FTD), compared with visual assessment alone. METHODS: Our forced-choice multi-rater clinical accuracy study used MRI from 16 AD patients, 14 FTD patients, and 15 healthy controls; age range 52-81. Our QReport was presented to raters with regional grey matter volumes plotted as percentiles against data from a normative population (n = 461). Nine raters with varying radiological experience (3 each: consultants, registrars, 'non-clinical image analysts') assessed each case twice (with and without the QReport). Raters were blinded to clinical and demographic information; they classified scans as 'normal' or 'abnormal' and if 'abnormal' as 'AD' or 'FTD'. RESULTS: The QReport improved sensitivity for detecting volume loss and AD across all raters combined (p = 0.015* and p = 0.002*, respectively). Only the consultant group's accuracy increased significantly when using the QReport (p = 0.02*). Overall, raters' agreement (Cohen's κ) with the 'gold standard' was not significantly affected by the QReport; only the consultant group improved significantly (κs 0.41â0.55, p = 0.04*). Cronbach's alpha for interrater agreement improved from 0.886 to 0.925, corresponding to an improvement from 'good' to 'excellent'. CONCLUSION: Our QReport referencing single-subject results to normative data alongside visual assessment improved sensitivity, accuracy, and interrater agreement for detecting volume loss. The QReport was most effective in the consultants, suggesting that experience is needed to fully benefit from the additional information provided by quantitative analyses. KEY POINTS: ⢠The use of quantitative report alongside routine visual MRI assessment improves sensitivity and accuracy for detecting volume loss and AD vs visual assessment alone. ⢠Consultant neuroradiologists' assessment accuracy and agreement (kappa scores) significantly improved with the use of quantitative atrophy reports. ⢠First multi-rater radiological clinical evaluation of visual quantitative MRI atrophy report for use as a diagnostic aid in dementia.
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Enfermedad de Alzheimer , Demencia Frontotemporal , Anciano , Anciano de 80 o más Años , Enfermedad de Alzheimer/diagnóstico por imagen , Atrofia , Demencia Frontotemporal/diagnóstico por imagen , Sustancia Gris , Humanos , Imagen por Resonancia Magnética , Persona de Mediana EdadRESUMEN
OBJECTIVES: Hippocampal sclerosis (HS) is a common cause of temporal lobe epilepsy. Neuroradiological practice relies on visual assessment, but quantification of HS imaging biomarkers-hippocampal volume loss and T2 elevation-could improve detection. We tested whether quantitative measures, contextualised with normative data, improve rater accuracy and confidence. METHODS: Quantitative reports (QReports) were generated for 43 individuals with epilepsy (mean age ± SD 40.0 ± 14.8 years, 22 men; 15 histologically unilateral HS; 5 bilateral; 23 MR-negative). Normative data was generated from 111 healthy individuals (age 40.0 ± 12.8 years, 52 men). Nine raters with different experience (neuroradiologists, trainees, and image analysts) assessed subjects' imaging with and without QReports. Raters assigned imaging normal, right, left, or bilateral HS. Confidence was rated on a 5-point scale. RESULTS: Correct designation (normal/abnormal) was high and showed further trend-level improvement with QReports, from 87.5 to 92.5% (p = 0.07, effect size d = 0.69). Largest magnitude improvement (84.5 to 93.8%) was for image analysts (d = 0.87). For bilateral HS, QReports significantly improved overall accuracy, from 74.4 to 91.1% (p = 0.042, d = 0.7). Agreement with the correct diagnosis (kappa) tended to increase from 0.74 ('fair') to 0.86 ('excellent') with the report (p = 0.06, d = 0.81). Confidence increased when correctly assessing scans with the QReport (p < 0.001, η2p = 0.945). CONCLUSIONS: QReports of HS imaging biomarkers can improve rater accuracy and confidence, particularly in challenging bilateral cases. Improvements were seen across all raters, with large effect sizes, greatest for image analysts. These findings may have positive implications for clinical radiology services and justify further validation in larger groups. KEY POINTS: ⢠Quantification of imaging biomarkers for hippocampal sclerosis-volume loss and raised T2 signal-could improve clinical radiological detection in challenging cases. ⢠Quantitative reports for individual patients, contextualised with normative reference data, improved diagnostic accuracy and confidence in a group of nine raters, in particular for bilateral HS cases. ⢠We present a pre-use clinical validation of an automated imaging assessment tool to assist clinical radiology reporting of hippocampal sclerosis, which improves detection accuracy.
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Epilepsia del Lóbulo Temporal , Epilepsia , Adulto , Epilepsia/patología , Epilepsia del Lóbulo Temporal/diagnóstico por imagen , Epilepsia del Lóbulo Temporal/patología , Hipocampo/diagnóstico por imagen , Hipocampo/patología , Humanos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Esclerosis/diagnóstico por imagen , Esclerosis/patologíaRESUMEN
Cardiovascular assessment of patients with Marfan syndrome has normally focused on the aortic root and vascular manifestations of the disease due to the high risk of aortic dissection. Although primary myocardial impairment has long been suspected in these patients, the evidence has been controversial. Advanced echocardiography and cardiovascular magnetic resonance imaging have proven to be effective, accurate, and more sensitive in the detection of subtle cardiac dysfunction. The application of these techniques to Marfan syndrome over the last 10 years has made significant progress in demonstrating the presence of primary myocardial impairment in these patients, but further work is still required to obtain confirmatory molecular, pathophysiological, and prognostic clinical data. Phenotypic expression of the disease has prognostic value, also suggesting potential effective medical therapy.
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Técnicas de Imagen Cardíaca/métodos , Ecocardiografía/métodos , Imagen por Resonancia Cinemagnética/métodos , Síndrome de Marfan/diagnóstico por imagen , Imagen Multimodal/métodos , Disfunción Ventricular/diagnóstico por imagen , Medicina Basada en la Evidencia , Humanos , Aumento de la Imagen/métodos , Reproducibilidad de los Resultados , Sensibilidad y EspecificidadRESUMEN
BACKGROUND: While speckle tracking echocardiography (2DSTE) can be used to study longitudinal, circumferential, and radial function, real time 3D echocardiography (3DE) generates dynamic time-volume curves, offering a wide array of new parameters for characterizing mechanical and volumetric properties of the left ventricle (LV). Our aim was to investigate the merit of these new techniques to separate normal from abnormal echocardiograms as well as to identify subclinical disease in reportedly normal subjects. METHODS: Eighty-one patients (mean age 61 ± 16 years) underwent standard 2D echocardiography (2DE) enhanced by 2DSTE and 3DE. The data included LV volumes and ejection fraction (EF), velocities, strain/strain rate, and peak ejection/filling rates. The patients were divided into Group 1: normal (n = 42) and Group 2: abnormal (n = 39) on the basis of an expert interpretation of the resting 2DE. RESULTS: Global longitudinal strain (%) was 17 ± 4 in Group1 and 14 ± 4 in Group2 (P < 0.002). Strain rates (SR, 1/sec) at peak systole (1.1 ± 0.2 vs 0.9 ± 0.3, P < 0.001) and early diastole (1.3 ± 0.3 vs 0.9 ± 0.3, P < 0.001) were also higher in Group1. Three-dimensional peak ejection and filling rates (EDV/sec) were significantly higher in Group1 (-2.5 ± 0.4 vs -2.1 ± 0.7, and 1.8 ± 0.2 vs 1.5 ± 0.5, P < 0.002, P < 0.001, respectively). The best discriminatory power for predicting a normal 2DE was systolic SR with a sensitivity of 82% and a specificity of 54% using a cutoff value of 1.09. Interestingly, 19/41 (46%) of Group1 patients had systolic SR < 1.09, suggesting subclinical disease. CONCLUSIONS: 2DSTE and 3DE can discriminate between normal and abnormal echocardiograms and have the potential to detect subclinical LV dysfunction.
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Ecocardiografía Tridimensional/métodos , Ecocardiografía/métodos , Diagnóstico por Imagen de Elasticidad/métodos , Disfunción Ventricular Izquierda/diagnóstico por imagen , Adulto , Anciano , Anciano de 80 o más Años , Sistemas de Computación , Femenino , Humanos , Masculino , Persona de Mediana Edad , Variaciones Dependientes del Observador , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Adulto JovenRESUMEN
BACKGROUND: Extracellular matrix remodeling in the aortic wall results in increased aortic stiffness (AoS) in Marfan syndrome (MFS). Pulsed-wave velocity (PWV) constitutes the best indirect AoS measurement. We aimed to assess PWV in MFS patients using two-dimensional (2D) and Doppler echocardiography. METHODS: Thirty-one MFS patients, (mean age 31 ± 14 years, 16 men) and 31 controls were examined. Blood flow was recorded in the aorta near the aortic valve and immediately after in the descending aorta with simultaneous electrocardiography. PWV was calculated by dividing the distance between the two sample volume positions (D) by the time difference (TD) between the intervals from the QRS start to the ascending and descending aortic flow onsets. B-stiffness was also measured. RESULTS: TD (described in "Methods" section) and, aortic arch length were significantly increased in MFS patients, P < 0.001. Thus, PWV values were significantly higher in patients when compared with controls, 7.20 m/s (5.12, 9.43) versus 4.64 m/s (3.37, 6.24), P < 0.001. B-stiffness was also significantly increased in MFS patients; 5.15 (3.69, 7.65) versus 2.44 (1.82, 3.66), P < 0.001. Multiple regression analysis showed a positive association with MFS diagnosis and age, (P = 0.002 and 0.009, respectively). Reproducibility of PWV measurements was <5%. CONCLUSIONS: AoS was significantly higher in MFS patients as expected. Our data demonstrated that PWV measurements can be performed, in the absence of serious musculoskeletal abnormalities in MFS adults, as part of a cardiac ultrasound scan. This technique can be helpful in diagnosis and management in MFS.
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Aorta/diagnóstico por imagen , Aorta/patología , Ecocardiografía Doppler , Síndrome de Marfan/diagnóstico por imagen , Adolescente , Adulto , Factores de Edad , Estudios de Casos y Controles , Femenino , Humanos , Masculino , Persona de Mediana Edad , Variaciones Dependientes del Observador , Adulto JovenRESUMEN
OBJECTIVE: To investigate the presence of any regional myocardial deformation abnormalities in Marfan syndrome (MFS) and determine the benefits of using advanced echocardiography compared to conventional techniques. BACKGROUND: Myocardial dysfunction in MFS may be caused by extracellular matrix remodeling thus, resulting in uniform reduced functionality. However, increased aortic stiffness may cause segmental ventricular abnormalities. Strain rate imaging (SRI) constitutes a validated technique to assess regional deformation in various clinical conditions. With this in mind, we aimed to investigate biventricular function in MFS using SRI. METHODS: Forty-four MFS patients (mean age 30 ± 12 years, 26 men) and 49 controls without valvular disease were examined using SRI. Ejection fraction (EF) was calculated by the Simpson's biplane method. Biventricular deformation was assessed by measuring strain/strain rate. Strain values were divided by left ventricular (LV) end-diastolic volume to adjust LV deformation for geometry changes providing a strain index (SI). Aortic stiffness was evaluated using the ß-stiffness index. RESULTS: EF (%) was reduced in MFS patients (59 ± 5 vs 72 ± 4, P < 0.001), whereas ß-stiffness was increased (P < 0.001). LV radial and LV and right ventricular (RV) long-axis strain values (%) were reduced in the patient group (70 ± 17 vs 93 ± 10; 19 ± 2 vs 25 ± 2; 30 ± 9 vs 36 ± 8, respectively, P < 0.001). Strain rate measurements were also reduced (P < 0.001). In a multiple regression analysis, MFS diagnosis was negatively associated with LV SI (-0.262 [-0.306, -0.219], P < 0.001). ß-Stiffness was negatively associated with SI obtained from the septum, inferior and anterior walls. ROC analyses demonstrated that SRI, when compared with conventional echocardiography, had higher sensitivity and specificity in predicting biventricular dysfunction in MFS. CONCLUSIONS: Our study showed a uniform reduction in biventricular deformation in MFS. These findings suggest that assessment of myocardial function using advanced echocardiographic techniques could be more accurate in MFS patient evaluation than conventional echocardiography alone.
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Ecocardiografía/métodos , Síndrome de Marfan/diagnóstico por imagen , Síndrome de Marfan/fisiopatología , Disfunción Ventricular Izquierda/diagnóstico por imagen , Disfunción Ventricular Izquierda/fisiopatología , Adulto , Estudios de Casos y Controles , Diástole/fisiología , Ecocardiografía Doppler , Electrocardiografía , Femenino , Humanos , Masculino , Curva ROC , Reproducibilidad de los Resultados , Sístole/fisiologíaRESUMEN
AIMS: Previous studies provided evidence about left ventricular systolic and diastolic dysfunction in adults with Marfan syndrome (MFS). However, in the literature, data on right ventricular and bi-atrial diastolic function are limited. We aimed to investigate whether, in the absence of significant valvular disease, diastolic dysfunction is present not only in both ventricles but also in the atrial cavities. METHODS AND RESULTS: Seventy-two adult unoperated MFS patients and 73 controls without significant differences in age, sex, and body surface area from the patient group were studied using two-dimensional, pulsed, and colour-Doppler and tissue-Doppler imaging (TDI). Biventricular early filling measurements were significantly decreased in MFS patients when compared with controls (P < 0.001). Pulsed TDI early filling measurements obtained from five mitral annular regions and over the lateral tricuspid valve corner were significantly reduced in the patient group (P < 0.001). Indices reflecting atrial function at the reservoir, conduit and contractile phases were also significantly decreased in MFS patients (P < 0.001). CONCLUSION: This study demonstrated significant biventricular diastolic and biatrial systolic and diastolic dysfunction in MFS patients. Our findings suggest that MFS affects diastolic function independently. Diastolic abnormalities could be attributed to fibrillin-1 deficiency and dysregulation of transforming growth factor-beta activity in the cardiac extracellular matrix.
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Ecocardiografía Doppler/métodos , Ecocardiografía/métodos , Síndrome de Marfan/diagnóstico por imagen , Disfunción Ventricular Izquierda/diagnóstico por imagen , Disfunción Ventricular Derecha/diagnóstico por imagen , Adulto , Estudios de Casos y Controles , Distribución de Chi-Cuadrado , Diástole/fisiología , Femenino , Fibrilina-1 , Fibrilinas , Humanos , Masculino , Síndrome de Marfan/fisiopatología , Proteínas de Microfilamentos/análisis , Análisis de Regresión , Sístole/fisiología , Factor de Crecimiento Transformador beta/análisis , Disfunción Ventricular Izquierda/fisiopatología , Disfunción Ventricular Derecha/fisiopatologíaRESUMEN
AIMS: The right ventricle (RV) ejects the same volume of blood at the same rate as the left ventricle (LV). Mild LV dysfunction has been demonstrated in Marfan syndrome (MFS). However, little attention has been paid to the functioning of the RV. The aim of this study was to assess RV function in unoperated adult MFS patients. METHODS AND RESULTS: In 66 unoperated (15-58 years) MFS patients and 61 controls, rate of pressure rise (dp/dt) in RV, and tricuspid annular motion (TAM) were studied using conventional echocardiography and tissue Doppler imaging (TDI). When compared with controls, MFS patients showed impaired RV systolic function as expressed by a reduced dp/dt, TAM obtained by M-mode echocardiography, and peak TDI systolic velocities at the basal lateral wall (745.36+/-37.85 vs. 1103.30+/-27.30 mmHg, P<0.001; 2.2+/-0.05 vs. 2.5+/-0.05 cm, P<0.001; and 0.13+/-0.002 vs. 0.16+/-0.002 m/s, P<0.001, respectively). CONCLUSION: This study demonstrated a primary impairment of RV systolic function in MFS. This is the first study to report RV dysfunction in MFS. Such data could prove valuable during the peri-operative and long-term medical management of MFS patients.
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Nodo Atrioventricular/patología , Ventrículos Cardíacos/fisiopatología , Síndrome de Marfan/fisiopatología , Válvula Tricúspide/patología , Disfunción Ventricular Derecha/fisiopatología , Función Ventricular Derecha , Adolescente , Antagonistas Adrenérgicos beta/uso terapéutico , Adulto , Factores de Edad , Nodo Atrioventricular/diagnóstico por imagen , Velocidad del Flujo Sanguíneo , Estudios de Casos y Controles , Femenino , Ventrículos Cardíacos/diagnóstico por imagen , Humanos , Masculino , Síndrome de Marfan/diagnóstico por imagen , Síndrome de Marfan/tratamiento farmacológico , Metaanálisis como Asunto , Persona de Mediana Edad , Sístole , Ultrasonografía Doppler , Disfunción Ventricular Derecha/diagnóstico por imagen , Adulto JovenRESUMEN
BACKGROUND: Fibrillin-1 deficiency, dysregulated cytokine transforming growth factor-beta, and increased collagen deposition related to fibrillin-1 gene mutations could predispose to impaired carotid compliance (CC) in Marfan syndrome (MFS). We sought to detect any alterations in CC using the vascular image analysis system (VIA). METHODS AND RESULTS: Thirty-two MFS patients, 20 men and 12 women (mean age 34.2 +/- 12.05 years), and 29 controls matched for age, sex, and body surface area (BSA) were recruited. The entire length of each carotid system was initially scanned longitudinally using a 14 MHz linear transducer. Then, a stereotactic clamp held the transducer in contact with the carotid artery. Arterial diameter changes during the cardiac cycle were recorded for 1 minute from both right (RCCA) and left common carotid arteries (LCCA) separately using the VIA system. RCCA and LCCA compliance and distensibility measurements were significantly reduced in MFS patients when compared to controls, P < 0.05. RCCA and LCCA intima-media thickness did not differ between patients and controls, P > 0.05. MFS diagnosis and age were associated with reduced CC in both carotid arteries after adjusting for variables such as, sex, BSA, heart rate, beta-blockade, intima-media thickness, and aortic root size. CONCLUSIONS: Our findings showed a reduction in CC in adult patients with MFS. This could be attributed to fibrillin-1 deficiency resulting in structural abnormalities in the carotid arterial wall.
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Arterias Carótidas/diagnóstico por imagen , Enfermedades de las Arterias Carótidas/diagnóstico por imagen , Ecocardiografía/métodos , Diagnóstico por Imagen de Elasticidad/métodos , Síndrome de Marfan/diagnóstico por imagen , Adulto , Sistemas de Computación , Módulo de Elasticidad , Femenino , Humanos , Masculino , Reproducibilidad de los Resultados , Sensibilidad y EspecificidadRESUMEN
There are numerous challenges to identifying, developing and implementing quantitative techniques for use in clinical radiology, suggesting the need for a common translational pathway. We developed the quantitative neuroradiology initiative (QNI), as a model framework for the technical and clinical validation necessary to embed automated segmentation and other image quantification software into the clinical neuroradiology workflow. We hypothesize that quantification will support reporters with clinically relevant measures contextualized with normative data, increase the precision of longitudinal comparisons, and generate more consistent reporting across levels of radiologists' experience. The QNI framework comprises the following steps: (1) establishing an area of clinical need and identifying the appropriate proven imaging biomarker(s) for the disease in question; (2) developing a method for automated analysis of these biomarkers, by designing an algorithm and compiling reference data; (3) communicating the results via an intuitive and accessible quantitative report; (4) technically and clinically validating the proposed tool pre-use; (5) integrating the developed analysis pipeline into the clinical reporting workflow; and (6) performing in-use evaluation. We will use current radiology practice in dementia as an example, where radiologists have established visual rating scales to describe the degree and pattern of atrophy they detect. These can be helpful, but are somewhat subjective and coarse classifiers, suffering from floor and ceiling limitations. Meanwhile, several imaging biomarkers relevant to dementia diagnosis and management have been proposed in the literature; some clinically approved radiology software tools exist but in general, these have not undergone rigorous clinical validation in high volume or in tertiary dementia centres. The QNI framework aims to address this need. Quantitative image analysis is developing apace within the research domain. Translating quantitative techniques into the clinical setting presents significant challenges, which must be addressed to meet the increasing demand for accurate, timely and impactful clinical imaging services.
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Encéfalo/diagnóstico por imagen , Encéfalo/patología , Demencia/diagnóstico , Demencia/patología , Imagen por Resonancia Magnética/métodos , Neuroimagen/métodos , Estudios de Evaluación como Asunto , HumanosRESUMEN
AIM: In the early stages of hypertension (HTN), when global left ventricular (LV) function is still unaffected, localized geometrical changes suggest changes in regional function. We investigated regional geometry and systolic deformation (using strain/strain rate (S/SR) imaging) in HTN. METHODS AND RESULTS: We studied 74 untreated mild to moderate HTNs and 34 matched normotensives (NTN). All had a standard echo including myocardial velocity data for regional radial and longitudinal deformation. Despite the absence of abnormalities in standard functional indices and LVH, non-uniform changes in regional geometry and deformation were observed. Besides a significant increase in wall thickness (WT) in all HTN segments, there was a gradual increase in WT from apex to base resulting in prominent basal septal hypertrophy. In HTN, regional longitudinal peak systolic SR (SSR) and end-systolic S (ESS) were significantly (P < 0.0001) reduced in the basal septum. In the lateral wall there was an increase in peak SSR and ESS (P < 0.05) basally. The basal septal ESS correlated both with mean arterial pressure and basal septal WT, with lower ESS for higher BP and thicker septum. CONCLUSION: Regionally differing geometrical remodelling occurs early in HTN. Longitudinal ESS and peak SSR are sensitive markers of early changes occurring in HTN.
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Hipertensión/diagnóstico por imagen , Disfunción Ventricular Izquierda/diagnóstico por imagen , Remodelación Ventricular , Adulto , Femenino , Humanos , Hipertensión/complicaciones , Hipertensión/fisiopatología , Masculino , Persona de Mediana Edad , Ultrasonografía , Disfunción Ventricular Izquierda/etiología , Disfunción Ventricular Izquierda/fisiopatologíaRESUMEN
AIMS: Marfan syndrome (MFS) is a connective tissue disorder caused by mutations in the fibrillin-1 (FBN1) gene. It has been observed that FBN1 deficient mice have reduced left ventricular (LV) systolic function which is correlated to increased transforming growth factor-beta activity. This study aimed to ascertain LV functional abnormalities in MFS patients using M-mode and tissue Doppler imaging (TDI). METHODS AND RESULTS: In 66 (15-58 years) MFS patients and 61 normal controls, ejection fraction (EF) was evaluated by Simpson's biplane method. Atrioventricular plane displacement (AVPD) obtained from five mitral annular regions was also assessed using M-mode and TDI techniques. To overcome limitations associated with conventional M-mode echocardiography, anatomical and colour anatomical M-mode were also utilized. Ejection fraction was significantly reduced in MFS patients when compared to controls (66.3 +/- 0.74 vs. 71.9 +/- 0.56, P < 0.001), although it was within the normal range. M-mode and TDI AVPD measurements obtained from lateral, septal, inferior, anterior and posterior mitral annular regions were also significantly reduced in MFS patients in comparison to controls (P <0.001, for all measurements). CONCLUSION: Left ventricular long-axis systolic function is significantly reduced in MFS patients. This data suggests that LV function should be monitored in MFS and appropriate treatment applied if necessary.
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Nodo Atrioventricular/fisiopatología , Ventrículos Cardíacos/fisiopatología , Síndrome de Marfan/fisiopatología , Adolescente , Adulto , Anciano , Nodo Atrioventricular/diagnóstico por imagen , Femenino , Ventrículos Cardíacos/diagnóstico por imagen , Humanos , Masculino , Síndrome de Marfan/diagnóstico por imagen , Persona de Mediana Edad , Volumen Sistólico , Sístole , Factores de Tiempo , Ultrasonografía , Adulto JovenRESUMEN
BACKGROUND: Although ultrasound systems generally archive to Picture Archiving and Communication Systems (PACS), their archiving workflow typically involves storage to an internal hard disk before data are transferred onwards. Deleting records from the local system will delete entries in the database and from the file allocation table or equivalent but, as with a PC, files can be recovered. Great care is taken with disposal of media from a healthcare organisation to prevent data breaches, but ultrasound systems are routinely returned to lease companies, sold on or donated to third parties without such controls. METHODS: In this project, five methods of hard disk erasure were tested on nine ultrasound systems being decommissioned: the system's own delete function; full reinstallation of system software; the manufacturer's own disk wiping service; open source disk wiping software for full and just blank space erasure. Attempts were then made to recover data using open source recovery tools. RESULTS: All methods deleted patient data as viewable from the ultrasound system and from browsing the disk from a PC. However, patient identifiable data (PID) could be recovered following the system's own deletion and the reinstallation methods. No PID could be recovered after using the manufacturer's wiping service or the open source wiping software. CONCLUSION: The typical method of reinstalling an ultrasound system's software may not prevent PID from being recovered. When transferring ownership, care should be taken that an ultrasound system's hard disk has been wiped to a sufficient level, particularly if the scanner is to be returned with approved parts and in a fully working state.
RESUMEN
OBJECTIVES: Clinical imaging data are essential for developing research software for computer-aided diagnosis, treatment planning and image-guided surgery, yet existing systems are poorly suited for data sharing between healthcare and academia: research systems rarely provide an integrated approach for data exchange with clinicians; hospital systems are focused towards clinical patient care with limited access for external researchers; and safe haven environments are not well suited to algorithm development. We have established GIFT-Cloud, a data and medical image sharing platform, to meet the needs of GIFT-Surg, an international research collaboration that is developing novel imaging methods for fetal surgery. GIFT-Cloud also has general applicability to other areas of imaging research. METHODS: GIFT-Cloud builds upon well-established cross-platform technologies. The Server provides secure anonymised data storage, direct web-based data access and a REST API for integrating external software. The Uploader provides automated on-site anonymisation, encryption and data upload. Gateways provide a seamless process for uploading medical data from clinical systems to the research server. RESULTS: GIFT-Cloud has been implemented in a multi-centre study for fetal medicine research. We present a case study of placental segmentation for pre-operative surgical planning, showing how GIFT-Cloud underpins the research and integrates with the clinical workflow. CONCLUSIONS: GIFT-Cloud simplifies the transfer of imaging data from clinical to research institutions, facilitating the development and validation of medical research software and the sharing of results back to the clinical partners. GIFT-Cloud supports collaboration between multiple healthcare and research institutions while satisfying the demands of patient confidentiality, data security and data ownership.
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Nube Computacional , Conducta Cooperativa , Diagnóstico por Imagen , Difusión de la Información , Seguridad Computacional , Administración Hospitalaria , Universidades/organización & administraciónRESUMEN
BACKGROUND: The assumption that the vastus medialis oblique (VMO) is involved in medial patellar stabilisation has led to speculation that patellofemoral pain (PF) may be a result of abnormal patellar tracking, due to weakness or difference in fibre orientation of the VMO. Recent studies have reported that the VMO fibre angle, measured in vivo with ultrasound (US), is reduced in patellofemoral pain (PF) patients. However, the validity of US in measuring this parameter was not investigated and this would inevitably cast doubt on whether the US results are comparable to direct measurement. The aim of this study was to validate the use of ultrasound (US) in measuring VMO fibre angle by comparing results obtained both from US and direct measurement. METHODS: The VMO fibre angle was determined in relation to the femoral axis in nine lower limbs from five soft-fixed cadavers, first using US and then by direct measurement. RESULTS: The Pearson correlation coefficient between the two methods was 0.92 (p<0.01) indicating a very strong relationship. The average difference in measurements between the two methods was 0.20. Bland/Altman analysis showed 95% limit of agreement to be between -2.550 and 30, showing minimal discrepancies between results obtained by the two methods. CONCLUSION: In conclusion, the VMO fibre angle values obtained by the US method were proved to be valid and comparable to those obtained from direct measurement. We show, therefore, that US can be used with confidence to measure VMO fibre angles in the cadaver, and, by implication, in clinical practice.
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Articulación de la Rodilla/diagnóstico por imagen , Músculo Cuádriceps/diagnóstico por imagen , Anciano , Anciano de 80 o más Años , Cadáver , Humanos , Articulación de la Rodilla/anatomía & histología , Persona de Mediana Edad , Músculo Cuádriceps/anatomía & histología , Reproducibilidad de los Resultados , UltrasonografíaRESUMEN
INTRODUCTION: several studies have documented increased aortic stiffness in patients with Marfan syndrome (MFS) using echocardiography and magnetic resonance imaging. Recent studies have also shown primary myocardial impairment in MFS. We investigated whether left ventricular (LV) function could be further impaired when acting against a stiff vascular system. METHODS: twenty-six MFS patients (mean age 30 ± 2 years, 17 males) and 30 normal controls were examined. Mitral annular displacement, as a surrogate for LV systolic function, was evaluated from septal, anterolateral, anterior and inferior regions using M-mode and tissue Doppler imaging. Septal/anterolateral and anterior/inferior M-mode displacement measurements were normalised by dividing them by the longitudinal inner distance obtained at end diastole from the 4- and 2-chamber views, respectively. Carotid-femoral and carotid-radial (CF and CR) pulse wave velocities (PWV) were determined using an automated applanation tonometry device. Central aortic pressure was assessed by recording radial waveforms with the tonometer and central waveforms were reconstructed using a generalised transfer function. RESULTS: CF- and CR-PWV were significantly increased in the patient group (p<0.001), whilst mitral annular displacement measurements were significantly reduced (p<0.001, all regions). Regression analysis demonstrated that the disease status and CF-PWV were strongly associated with reduced LV systolic function (p<0.001, p=0.002, respectively). CONCLUSIONS: our study showed reduced LV systolic function and increased aortic stiffness in MFS patients. The efficiency of a fibrillin-1 deficient heart may be further reduced by ejection into a stiff vascular system. Care should be taken to ensure that any treatment regime addresses both increased aortic stiffness and myocardial dysfunction in MFS.
Asunto(s)
Aorta/patología , Síndrome de Marfan/patología , Función Ventricular Izquierda/fisiología , Adulto , Velocidad del Flujo Sanguíneo , Elasticidad , Diagnóstico por Imagen de Elasticidad , Femenino , Humanos , Masculino , Manometría , Síndrome de Marfan/fisiopatología , Sístole/fisiologíaRESUMEN
BACKGROUND AND OBJECTIVES: Early changes in left atrial function in hypertension are difficult to assess quantitatively. Measuring atrial reversal flow into the pulmonary veins and regional left atrial deformation parameters assessed by Tissue Doppler-derived strain/rate (S/SR) imaging could provide quantitative assessment of left atrial deformation. We aimed to quantify changes in left atrial volume and deformation and pulmonary flow reversal (PVREVERS) in hypertension to detect subclinical left atrial dysfunction. DESIGN, SETTING AND PATIENTS: In 74 hypertensive and 34 age-matched normotensive patients (mean age 49 +/- 1.4 vs. 44.2 +/- 2.1 years) echo studies were performed, including measurements of LAV during reservoir, conduit and pump phases and standard indices reflecting left ventricular filling. S/SR was measured in the lateral left atrial wall. Total deformation (STOTAL) and the contribution to early (SE-index) and late (SA-index) filling were calculated. RESULTS: Hypertensive patients had significantly impaired diastolic function and increased left atrial volume during all phases. Only LAVCONDUIT significantly correlated with both ventricular hypertrophy and parameters of diastolic function. Velocity time integral of PVREVERS correlated with blood pressure and LAVCONDUIT. In hypertensive patients STOTAL was significantly higher (54.9 +/- 2.6 vs. 45.5 +/- 2.7%, P < 0.03) and SE-index was lower (P < 0.0001). This was compensated for by an increased SA-index (P < 0.0001) and SR during atrial contraction (-4.9 +/- 0.2 vs. -2.9 +/- 0.3 1/s, P < 0.0001). SA-index correlated significantly with blood pressure (R = 0.4; P < 0.0001) and PVREVERS (R = 0.3; P < 0.001). CONCLUSION: Changes in left atrial function due to hypertensive diastolic impairment are best reflected by LAVCONDUIT expansion. Hypertensive atrial dilatation is related to increase in PVREVERS. Left atrial S/SR offers a clinically valuable approach to detecting subclinical atrial dysfunction.