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1.
BMC Health Serv Res ; 23(1): 1209, 2023 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-37932722

RESUMO

BACKGROUND: Health literacy holds significant importance for medical professionals, as it is widely acknowledged as a key element in enhancing health promotion and overall well-being. The primary objective of this study is to explore Greek physicians' comprehension of health literacy, the significance they attribute to it, their strategies for addressing patients with low health literacy, and the potential barriers they face while striving to enhance a patient's health literacy. In this context, we examine the communication methods employed by physicians as an integral part of their approach to improving a patient's health literacy. METHODS: A qualitative study was conducted between April 29, 2021, and February 17, 2022, utilizing in-depth, semi-structured interviews with 30 Greek medical professionals, of whom 15 were university professors. The research sample selection methodology employed in this study was purposive sampling. Data analysis was conducted using inductive thematic analysis. RESULTS: The majority of physicians were not familiar with the concept of health literacy. The most significant barriers to the development of health literacy among physicians are a lack of time, issues within the healthcare system, and interference from third parties, although they acknowledge that a significant portion of the responsibility lies with them. Effective communication with patients is important for all physicians, as it plays a crucial role in the therapeutic process. When they realize that their patients are not understanding them, they employ communication methods such as using plain language, providing numerous examples, incorporating visuals like pictures and even using drawings. CONCLUSIONS: The findings of this study underscore the importance of implementing targeted initiatives to promote health literacy within the Greek medical and academic community. Integrating health literacy training for physicians into the educational and training curriculum is essential. To accomplish this goal, it is imperative to first address the shortcomings within the healthcare system and improve the working conditions for physicians.


Assuntos
Letramento em Saúde , Médicos , Humanos , Promoção da Saúde , Pesquisa Qualitativa , Idioma
2.
Invest Radiol ; 54(8): 500-516, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31058661

RESUMO

OBJECTIVES: The aim of this study was to provide an ultrasound-based super-resolution methodology that can be implemented using clinical 2-dimensional ultrasound equipment and standard contrast-enhanced ultrasound modes. In addition, the aim is to achieve this for true-to-life patient imaging conditions, including realistic examination times of a few minutes and adequate image penetration depths that can be used to scan entire organs without sacrificing current super-resolution ultrasound imaging performance. METHODS: Standard contrast-enhanced ultrasound was used along with bolus or infusion injections of SonoVue (Bracco, Geneva, Switzerland) microbubble (MB) suspensions. An image analysis methodology, translated from light microscopy algorithms, was developed for use with ultrasound contrast imaging video data. New features that are tailored for ultrasound contrast image data were developed for MB detection and segmentation, so that the algorithm can deal with single and overlapping MBs. The method was tested initially on synthetic data, then with a simple microvessel phantom, and then with in vivo ultrasound contrast video loops from sheep ovaries. Tracks detailing the vascular structure and corresponding velocity map of the sheep ovary were reconstructed. Images acquired from light microscopy, optical projection tomography, and optical coherence tomography were compared with the vasculature network that was revealed in the ultrasound contrast data. The final method was applied to clinical prostate data as a proof of principle. RESULTS: Features of the ovary identified in optical modalities mentioned previously were also identified in the ultrasound super-resolution density maps. Follicular areas, follicle wall, vessel diameter, and tissue dimensions were very similar. An approximately 8.5-fold resolution gain was demonstrated in vessel width, as vessels of width down to 60 µm were detected and verified (λ = 514 µm). Best agreement was found between ultrasound measurements and optical coherence tomography with 10% difference in the measured vessel widths, whereas ex vivo microscopy measurements were significantly lower by 43% on average. The results were mostly achieved using video loops of under 2-minute duration that included respiratory motion. A feasibility study on a human prostate showed good agreement between density and velocity ultrasound maps with the histological evaluation of the location of a tumor. CONCLUSIONS: The feasibility of a 2-dimensional contrast-enhanced ultrasound-based super-resolution method was demonstrated using in vitro, synthetic and in vivo animal data. The method reduces the examination times to a few minutes using state-of-the-art ultrasound equipment and can provide super-resolution maps for an entire prostate with similar resolution to that achieved in other studies.


Assuntos
Meios de Contraste , Aumento da Imagem/métodos , Microvasos/diagnóstico por imagem , Ovário/irrigação sanguínea , Ovário/diagnóstico por imagem , Fosfolipídeos , Hexafluoreto de Enxofre , Ultrassonografia/métodos , Algoritmos , Animais , Feminino , Humanos , Técnicas In Vitro , Microbolhas , Modelos Animais , Imagens de Fantasmas , Ovinos
3.
IEEE Trans Med Imaging ; 38(1): 194-204, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30059295

RESUMO

Minimum Variance (MV) beamforming is known to improve the lateral resolution of ultrasound images and enhance the separation of isolated point scatterers. This paper aims to evaluate the adaptive beamformer's performance with flowing microbubbles (MBs) which are relevant to super-resolution ultrasound imaging. Simulations using point scatterer data from single emissions were complemented by an experimental investigation performed using a capillary tube phantom and the Synthetic Aperture Real-time Ultrasound System (SARUS). The MV performance was assessed by the minimum distance that allows the display of two scatterers positioned side-by-side, the lateral Full-Width-at-Half-Maximum (FWHM), and the Peak-Sidelobe-Level (PSL). In the tube, scatterer responses separated by down to [Formula: see text] (or 1.05λ ) were distinguished by the MV method, while the standard Delay-And-Sum (DAS) beamformers were unable to achieve such separation. Up to ninefold FWHM decrease was also measured in favor of the MV beamformer for individual echoes from MBs. The lateral distance between two scatterers impacted on their FWHM value, and additional differences in the scatterers' axial or out-of-plane position also impacted on their size and appearance. The simulation and experimental results were in agreement in terms of lateral resolution. The point scatterer study showed that the proposed MV imaging scheme provided clear resolution benefits compared to DAS. Current super-resolution methods mainly depend on DAS beamformers. Instead, the use of the MV method may provide a larger number of detected, and potentially better localized, MB scatterers.


Assuntos
Processamento de Imagem Assistida por Computador/métodos , Processamento de Sinais Assistido por Computador , Ultrassonografia/métodos , Microbolhas , Imagens de Fantasmas
4.
IEEE Trans Biomed Eng ; 65(8): 1840-1851, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29989960

RESUMO

OBJECTIVE: This paper aims to develop a method for achieving micrometre axial scatterer localization for medical ultrasound, surpassing the inherent, pulse length dependence limiting ultrasound imaging. METHODS: The method, directly translated from cellular microscopy, is based on multi-focal imaging and the simple, aberration-dependent, image sharpness metric of a single point scatterer. The localization of a point scatterer relies on the generation of multiple overlapping sharpness curves, created by deploying three foci during receive processing, and by assessing the sharpness values after each acquisition as a function of depth. Each derived curve peaks around the receive focus and the unique position of the scatterer is identified by combining the data from all curves using a maximum likelihood algorithm with a calibration standard. RESULTS: Simulated and experimental ultrasound point scatter data show that the sharpness method can provide scatterer axial localization with an average accuracy down to 10.21 m ( 21) and with up to 11.4 times increased precision compared to conventional localization. The improvements depend on the rate of change of sharpness using each focus, and the signal to noise ratio in each image. CONCLUSION: Super-resolution axial imaging from optical microscopy has been successfully translated into ultrasound imaging by using raw ultrasound data and standard beamforming. SIGNIFICANCE: The normalized sharpness method has the potential to be used in scatterer localization applications and contribute in current super-resolution ultrasound imaging techniques.


Assuntos
Processamento de Imagem Assistida por Computador/métodos , Processamento de Sinais Assistido por Computador , Ultrassonografia/métodos , Algoritmos , Imagens de Fantasmas
5.
Ultrasonics ; 79: 87-95, 2017 08.
Artigo em Inglês | MEDLINE | ID: mdl-28458062

RESUMO

Recent progress in adaptive beamforming techniques for medical ultrasound has shown that current resolution limits can be surpassed. One method of obtaining improved lateral resolution is the Minimum Variance (MV) beamformer. The frequency domain implementation of this method effectively divides the broadband ultrasound signals into sub-bands (MVS) to conform with the narrow-band assumption of the original MV theory. This approach is investigated here using experimental Synthetic Aperture (SA) data from wire and cyst phantoms. A 7MHz linear array transducer is used with the SARUS experimental ultrasound scanner for the data acquisition. The lateral resolution and the contrast obtained, are evaluated and compared with those from the conventional Delay-and-Sum (DAS) beamformer and the MV temporal implementation (MVT). From the wire phantom the Full-Width-at-Half-Maximum (FWHM) measured at a depth of 52mm, is 16.7µm (0.08λ) for both MV methods, while the corresponding values for the DAS case are at least 24 times higher. The measured Peak-Side-lobe-Level (PSL) may reach -41dB using the MVS approach, while the values from the DAS and MVT beamforming are above -24dB and -33dB, respectively. From the cyst phantom, the power ratio (PR), the contrast-to-noise ratio (CNR), and the speckle signal-to-noise ratio (sSNR) measured at a depth of 30mm are at best similar for MVS and DAS, with values ranging between -29dB and -30dB, 1.94 and 2.05, and 2.16 and 2.27 respectively. In conclusion the MVS beamformer is not suitable for imaging continuous targets, and significant resolution gains were obtained only for isolated targets.

6.
Artigo em Inglês | MEDLINE | ID: mdl-26737920

RESUMO

An ultrasound imaging technique providing sub-diffraction limit axial resolution for point sources is proposed. It is based on simultaneously acquired multi-focal images of the same object, and on the image metric of sharpness. The sharpness is extracted by image data and presents higher values for in-focus images. The technique is derived from biological microscopy and is validated here with simulated ultrasound data. A linear array probe is used to scan a point scatterer phantom that moves in depth with a controlled step. From the beamformed responses of each scatterer position the image sharpness is assessed. Values from all positions plotted together form a curve that peaks at the receive focus, which is set during the beamforming. Selection of three different receive foci for each acquired dataset will result in the generation of three overlapping sharpness curves. A set of three calibration curves combined with the use of a maximum-likelihood algorithm is then able to estimate, with high precision, the depth location of any emitter fron each single image. Estimated values are compared with the ground truth demonstrating that an accuracy of 28.6 µm (0.13λ) is achieved for a 4 mm depth range.


Assuntos
Imageamento Tridimensional/métodos , Ultrassom/métodos , Algoritmos , Calibragem , Simulação por Computador , Humanos , Imagens de Fantasmas
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