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1.
Cureus ; 14(11): e31669, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36545166

RESUMO

Minorities, particularly non-White minorities, often encounter implicit biases from healthcare professionals that may impact their standard of care and quality of life. The study of dermatology has long been based on Whites, unintentionally affecting the treatment of non-White patients. Melanoma, although mostly curable, can become fatal in those presenting with advanced stages at diagnosis. Despite being rare in racial minorities, melanoma is associated with a worse prognosis among them compared to White populations. In light of this, the objective of this study was to determine the role of education in preventing biases and improving the diagnosis and treatment of melanoma in minority groups to improve patient outcomes. This study was designed as a scoping review to gather evidence on the impact of implicit bias and lack of education on the treatment of melanoma in people of color. Following Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, we searched for peer-reviewed studies involving melanoma, education, and treatment bias in people of color on the databases PubMed, Medline EBSCO, CINAHL, and Cochrane. The data were extracted pertaining to the following main aspects: (1) risk factors, (2) surveys of current knowledge, and 3) educational interventions. This scoping review identified socioeconomic factors, bias, and lack of education in minority populations as causes of increased mortality rates in melanoma. Moreover, because preventative dermatology is largely based on White skin types, incorporating darker skin tones into education will help dispel implicit bias. Additionally, there is evidence to indicate that current patient knowledge and understanding of skin cancer is inaccurate among many and can be significantly improved through educational interventions, such as brochures and videos. Further educational interventions may be beneficial to increase understanding of melanoma in populations of color to address health disparities in dermatological care.

3.
Philos Trans A Math Phys Eng Sci ; 380(2233): 20210299, 2022 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-35965467

RESUMO

We report on an ongoing collaboration between epidemiological modellers and visualization researchers by documenting and reflecting upon knowledge constructs-a series of ideas, approaches and methods taken from existing visualization research and practice-deployed and developed to support modelling of the COVID-19 pandemic. Structured independent commentary on these efforts is synthesized through iterative reflection to develop: evidence of the effectiveness and value of visualization in this context; open problems upon which the research communities may focus; guidance for future activity of this type and recommendations to safeguard the achievements and promote, advance, secure and prepare for future collaborations of this kind. In describing and comparing a series of related projects that were undertaken in unprecedented conditions, our hope is that this unique report, and its rich interactive supplementary materials, will guide the scientific community in embracing visualization in its observation, analysis and modelling of data as well as in disseminating findings. Equally we hope to encourage the visualization community to engage with impactful science in addressing its emerging data challenges. If we are successful, this showcase of activity may stimulate mutually beneficial engagement between communities with complementary expertise to address problems of significance in epidemiology and beyond. See https://ramp-vis.github.io/RAMPVIS-PhilTransA-Supplement/. This article is part of the theme issue 'Technical challenges of modelling real-life epidemics and examples of overcoming these'.


Assuntos
COVID-19 , Pandemias , COVID-19/epidemiologia , Humanos
4.
Artigo em Inglês | MEDLINE | ID: mdl-35271448

RESUMO

We present the results of a double-blind phase 2b randomized control trial that used a custom built virtual reality environment for the cognitive rehabilitation of stroke survivors. A stroke causes damage to the brain and problem solving, memory and task sequencing are commonly affected. The brain can recover to some extent, however, and stroke patients have to relearn how to carry out activities of daily living. We have created an application called VIRTUE to enable such activities to be practiced using immersive virtual reality. Gamification techniques enhance the motivation of patients such as by making the level of difficulty of a task increase over time. The design and implementation of VIRTUE is described together with the results of the trial conducted within the Stroke Unit of a large hospital. We report on the safety and acceptability of VIRTUE. We have also observed particular benefits of VR treatment for stroke survivors that experienced more severe cognitive impairment, and an encouraging reduction in time spent in the hospital for all patients that received the VR treatment.


Assuntos
Reabilitação do Acidente Vascular Cerebral , Acidente Vascular Cerebral , Terapia de Exposição à Realidade Virtual , Realidade Virtual , Atividades Cotidianas , Cognição , Humanos , Acidente Vascular Cerebral/psicologia , Reabilitação do Acidente Vascular Cerebral/métodos , Sobreviventes , Terapia de Exposição à Realidade Virtual/métodos
5.
IEEE Trans Vis Comput Graph ; 27(7): 3213-3225, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31944959

RESUMO

We present VRIA, a Web-based framework for creating Immersive Analytics (IA) experiences in Virtual Reality. VRIA is built upon WebVR, A-Frame, React and D3.js, and offers a visualization creation workflow which enables users, of different levels of expertise, to rapidly develop Immersive Analytics experiences for the Web. The use of these open-standards Web-based technologies allows us to implement VR experiences in a browser and offers strong synergies with popular visualization libraries, through the HTML Document Object Model (DOM). This makes VRIA ubiquitous and platform-independent. Moreover, by using WebVR's progressive enhancement, the experiences VRIA creates are accessible on a plethora of devices. We elaborate on our motivation for focusing on open-standards Web technologies, present the VRIA creation workflow and detail the underlying mechanics of our framework. We also report on techniques and optimizations necessary for implementing Immersive Analytics experiences on the Web, discuss scalability implications of our framework, and present a series of use case applications to demonstrate the various features of VRIA. Finally, we discuss current limitations of our framework, the lessons learned from its development, and outline further extensions.

6.
IEEE Trans Med Imaging ; 39(5): 1615-1625, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-31751268

RESUMO

Surgical smoke removal algorithms can improve the quality of intra-operative imaging and reduce hazards in image-guided surgery, a highly desirable post-process for many clinical applications. These algorithms also enable effective computer vision tasks for future robotic surgery. In this article, we present a new unsupervised learning framework for high-quality pixel-wise smoke detection and removal. One of the well recognized grand challenges in using convolutional neural networks (CNNs) for medical image processing is to obtain intra-operative medical imaging datasets for network training and validation, but availability and quality of these datasets are scarce. Our novel training framework does not require ground-truth image pairs. Instead, it learns purely from computer-generated simulation images. This approach opens up new avenues and bridges a substantial gap between conventional non-learning based methods and which requiring prior knowledge gained from extensive training datasets. Inspired by the Generative Adversarial Network (GAN), we have developed a novel generative-collaborative learning scheme that decomposes the de-smoke process into two separate tasks: smoke detection and smoke removal. The detection network is used as prior knowledge, and also as a loss function to maximize its support for training of the smoke removal network. Quantitative and qualitative studies show that the proposed training framework outperforms the state-of-the-art de-smoking approaches including the latest GAN framework (such as PIX2PIX). Although trained on synthetic images, experimental results on clinical images have proved the effectiveness of the proposed network for detecting and removing surgical smoke on both simulated and real-world laparoscopic images.


Assuntos
Processamento de Imagem Assistida por Computador , Fumaça , Algoritmos , Redes Neurais de Computação , Radiografia
7.
Carbohydr Polym ; 198: 109-118, 2018 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-30092980

RESUMO

Sargassum in the Caribbean region has affected the livelihood of several coastal communities due to the influx of large quantities of the seaweed in recent times. This article seeks to explore how waste Sargassum natans can be utilized to produce sodium alginate. The novelty in this research lies in the optimization process, whereby multistage extraction and precipitation were investigated over commonly used single stage processing, in an effort to maximize both yield and purity. The results showed that a maximum yield of 19% was observed after 1 stage, while the purity was 74% after 4 stages. In addition, optimization of the multistage precipitation process using the Global Optimization Toolbox in MATLAB R2017b provided a novel model which indicated that a compromise between the maximum purity and yield can be obtained at 3 stages; 71-74% and 12-16% respectively. Furthermore, characterization was done using FTIR and NMR, with results comparable to a commercial sodium alginate brand, giving absorption bands at 1610 cm-1 and 1395 cm-1 and an M/G ratio of 0.51 respectively.

8.
Artigo em Inglês | MEDLINE | ID: mdl-30136971

RESUMO

Visualization and virtual environments (VEs) have been two interconnected parallel strands in visual computing for decades. Some VEs have been purposely developed for visualization applications, while many visualization applications are exemplary showcases in general-purpose VEs. Because of the development and operation costs of VEs, the majority of visualization applications in practice have yet to benefit from the capacity of VEs. In this paper, we examine this status quo from an information-theoretic perspective. Our objectives are to conduct cost-benefit analysis on typical VE systems (including augmented and mixed reality, theater-based systems, and large powerwalls), to explain why some visualization applications benefit more from VEs than others, and to sketch out pathways for the future development of visualization applications in VEs. We support our theoretical propositions and analysis using theories and discoveries in the literature of cognitive sciences and the practical evidence reported in the literatures of visualization and VEs.

9.
Comput Methods Programs Biomed ; 158: 135-146, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29544779

RESUMO

BACKGROUND AND OBJECTIVE: While Minimally Invasive Surgery (MIS) offers considerable benefits to patients, it also imposes big challenges on a surgeon's performance due to well-known issues and restrictions associated with the field of view (FOV), hand-eye misalignment and disorientation, as well as the lack of stereoscopic depth perception in monocular endoscopy. Augmented Reality (AR) technology can help to overcome these limitations by augmenting the real scene with annotations, labels, tumour measurements or even a 3D reconstruction of anatomy structures at the target surgical locations. However, previous research attempts of using AR technology in monocular MIS surgical scenes have been mainly focused on the information overlay without addressing correct spatial calibrations, which could lead to incorrect localization of annotations and labels, and inaccurate depth cues and tumour measurements. In this paper, we present a novel intra-operative dense surface reconstruction framework that is capable of providing geometry information from only monocular MIS videos for geometry-aware AR applications such as site measurements and depth cues. We address a number of compelling issues in augmenting a scene for a monocular MIS environment, such as drifting and inaccurate planar mapping. METHODS: A state-of-the-art Simultaneous Localization And Mapping (SLAM) algorithm used in robotics has been extended to deal with monocular MIS surgical scenes for reliable endoscopic camera tracking and salient point mapping. A robust global 3D surface reconstruction framework has been developed for building a dense surface using only unorganized sparse point clouds extracted from the SLAM. The 3D surface reconstruction framework employs the Moving Least Squares (MLS) smoothing algorithm and the Poisson surface reconstruction framework for real time processing of the point clouds data set. Finally, the 3D geometric information of the surgical scene allows better understanding and accurate placement AR augmentations based on a robust 3D calibration. RESULTS: We demonstrate the clinical relevance of our proposed system through two examples: (a) measurement of the surface; (b) depth cues in monocular endoscopy. The performance and accuracy evaluations of the proposed framework consist of two steps. First, we have created a computer-generated endoscopy simulation video to quantify the accuracy of the camera tracking by comparing the results of the video camera tracking with the recorded ground-truth camera trajectories. The accuracy of the surface reconstruction is assessed by evaluating the Root Mean Square Distance (RMSD) of surface vertices of the reconstructed mesh with that of the ground truth 3D models. An error of 1.24 mm for the camera trajectories has been obtained and the RMSD for surface reconstruction is 2.54 mm, which compare favourably with previous approaches. Second, in vivo laparoscopic videos are used to examine the quality of accurate AR based annotation and measurement, and the creation of depth cues. These results show the potential promise of our geometry-aware AR technology to be used in MIS surgical scenes. CONCLUSIONS: The results show that the new framework is robust and accurate in dealing with challenging situations such as the rapid endoscopy camera movements in monocular MIS scenes. Both camera tracking and surface reconstruction based on a sparse point cloud are effective and operated in real-time. This demonstrates the potential of our algorithm for accurate AR localization and depth augmentation with geometric cues and correct surface measurements in MIS with monocular endoscopes.


Assuntos
Procedimentos Cirúrgicos Minimamente Invasivos/métodos , Visão Monocular , Algoritmos , Simulação por Computador , Humanos , Imageamento Tridimensional/métodos
10.
IEEE Trans Vis Comput Graph ; 24(5): 1867-1878, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-28475060

RESUMO

Navigating a powered wheelchair and avoiding collisions is often a daunting task for new wheelchair users. It takes time and practice to gain the coordination needed to become a competent driver and this can be even more of a challenge for someone with a disability. We present a cost-effective virtual reality (VR) application that takes advantage of consumer level VR hardware. The system can be easily deployed in an assessment centre or for home use, and does not depend on a specialized high-end virtual environment such as a Powerwall or CAVE. This paper reviews previous work that has used virtual environments technology for training tasks, particularly wheelchair simulation. We then describe the implementation of our own system and the first validation study carried out using thirty three able bodied volunteers. The study results indicate that at a significance level of 5 percent then there is an improvement in driving skills from the use of our VR system. We thus have the potential to develop the competency of a wheelchair user whilst avoiding the risks inherent to training in the real world. However, the occurrence of cybersickness is a particular problem in this application that will need to be addressed.


Assuntos
Educação de Pacientes como Assunto/métodos , Realidade Virtual , Cadeiras de Rodas , Adulto , Gráficos por Computador , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
11.
Healthc Technol Lett ; 4(5): 163-167, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29184658

RESUMO

The potential of augmented reality (AR) technology to assist minimally invasive surgery (MIS) lies in its computational performance and accuracy in dealing with challenging MIS scenes. Even with the latest hardware and software technologies, achieving both real-time and accurate augmented information overlay in MIS is still a formidable task. In this Letter, the authors present a novel real-time AR framework for MIS that achieves interactive geometric aware AR in endoscopic surgery with stereo views. The authors' framework tracks the movement of the endoscopic camera and simultaneously reconstructs a dense geometric mesh of the MIS scene. The movement of the camera is predicted by minimising the re-projection error to achieve a fast tracking performance, while the three-dimensional mesh is incrementally built by a dense zero mean normalised cross-correlation stereo-matching method to improve the accuracy of the surface reconstruction. The proposed system does not require any prior template or pre-operative scan and can infer the geometric information intra-operatively in real time. With the geometric information available, the proposed AR framework is able to interactively add annotations, localisation of tumours and vessels, and measurement labelling with greater precision and accuracy compared with the state-of-the-art approaches.

12.
Stud Health Technol Inform ; 220: 134-41, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27046566

RESUMO

Control of a powered wheelchair is often not intuitive, making training of new users a challenging and sometimes hazardous task. Collisions, due to a lack of experience can result in injury for the user and other individuals. By conducting training activities in virtual reality (VR), we can potentially improve driving skills whilst avoiding the risks inherent to the real world. However, until recently VR technology has been expensive and limited the commercial feasibility of a general training solution. We describe Wheelchair-Rift, a cost effective prototype simulator that makes use of the Oculus Rift head mounted display and the Leap Motion hand tracking device. It has been assessed for face validity by a panel of experts from a local Posture and Mobility Service. Initial results augur well for our cost-effective training solution.


Assuntos
Instrução por Computador/economia , Instrução por Computador/métodos , Treinamento com Simulação de Alta Fidelidade/economia , Interface Usuário-Computador , Cadeiras de Rodas/economia , Instrução por Computador/instrumentação , Análise Custo-Benefício , Treinamento com Simulação de Alta Fidelidade/métodos , Ensino , Reino Unido
13.
Int J Intell Sci ; 5(1): 44-62, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26594595

RESUMO

Efficiently querying Description Logic (DL) ontologies is becoming a vital task in various data-intensive DL applications. Considered as a basic service for answering object queries over DL ontologies, instance checking can be realized by using the most specific concept (MSC) method, which converts instance checking into subsumption problems. This method, however, loses its simplicity and efficiency when applied to large and complex ontologies, as it tends to generate very large MSCs that could lead to intractable reasoning. In this paper, we propose a revision to this MSC method for DL [Formula: see text], allowing it to generate much simpler and smaller concepts that are specific enough to answer a given query. With independence between computed MSCs, scalability for query answering can also be achieved by distributing and parallelizing the computations. An empirical evaluation shows the efficacy of our revised MSC method and the significant efficiency achieved when using it for answering object queries.

14.
Med Biol Eng Comput ; 53(10): 961-74, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25947095

RESUMO

Two-dimensional asymmetry, border irregularity, colour variegation and diameter (ABCD) features are important indicators currently used for computer-assisted diagnosis of malignant melanoma (MM); however, they often prove to be insufficient to make a convincing diagnosis. Previous work has demonstrated that 3D skin surface normal features in the form of tilt and slant pattern disruptions are promising new features independent from the existing 2D ABCD features. This work investigates that whether improved lesion classification can be achieved by combining the 3D features with the 2D ABCD features. Experiments using a nonlinear support vector machine classifier show that many combinations of the 2D ABCD features and the 3D features can give substantially better classification accuracy than using (1) single features and (2) many combinations of the 2D ABCD features. The best 2D and 3D feature combination includes the overall 3D skin surface disruption, the asymmetry and all the three colour channel features. It gives an overall 87.8 % successful classification, which is better than the best single feature with 78.0 % and the best 2D feature combination with 83.1 %. These demonstrate that (1) the 3D features have additive values to improve the existing lesion classification and (2) combining the 3D feature with all the 2D features does not lead to the best lesion classification. The two ABCD features not selected by the best 2D and 3D combination, namely (1) the border feature and (2) the diameter feature, were also studied in separate experiments. It found that inclusion of either feature in the 2D and 3D combination can successfully classify 3 out of 4 lesion groups. The only one group not accurately classified by either feature can be classified satisfactorily by the other. In both cases, they have shown better classification performances than those without the 3D feature in the combinations. This further demonstrates that (1) the 3D feature can be used to improve the existing 2D-based diagnosis and (2) including the 3D feature with subsets of the 2D features can be used in distinguishing different benign lesion classes from MM. It is envisaged that classification performance may be further improved if different 2D and 3D feature subsets demonstrated in this study are used in different stages to target different benign lesion classes in future studies.


Assuntos
Interpretação de Imagem Assistida por Computador/métodos , Imageamento Tridimensional/métodos , Melanoma/diagnóstico , Neoplasias Cutâneas/diagnóstico , Humanos , Melanoma/patologia , Neoplasias Cutâneas/patologia , Propriedades de Superfície
15.
Artif Intell Appl ; 2(1): 8-31, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26848490

RESUMO

The extraction of logically-independent fragments out of an ontology ABox can be useful for solving the tractability problem of querying ontologies with large ABoxes. In this paper, we propose a formal definition of an ABox module, such that it guarantees complete preservation of facts about a given set of individuals, and thus can be reasoned independently w.r.t. the ontology TBox. With ABox modules of this type, isolated or distributed (parallel) ABox reasoning becomes feasible, and more efficient data retrieval from ontology ABoxes can be attained. To compute such an ABox module, we present a theoretical approach and also an approximation for SHIQ ontologies. Evaluation of the module approximation on different types of ontologies shows that, on average, extracted ABox modules are significantly smaller than the entire ABox, and the time for ontology reasoning based on ABox modules can be improved significantly.

16.
IEEE Trans Med Imaging ; 34(10): 1993-2024, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25494501

RESUMO

In this paper we report the set-up and results of the Multimodal Brain Tumor Image Segmentation Benchmark (BRATS) organized in conjunction with the MICCAI 2012 and 2013 conferences. Twenty state-of-the-art tumor segmentation algorithms were applied to a set of 65 multi-contrast MR scans of low- and high-grade glioma patients-manually annotated by up to four raters-and to 65 comparable scans generated using tumor image simulation software. Quantitative evaluations revealed considerable disagreement between the human raters in segmenting various tumor sub-regions (Dice scores in the range 74%-85%), illustrating the difficulty of this task. We found that different algorithms worked best for different sub-regions (reaching performance comparable to human inter-rater variability), but that no single algorithm ranked in the top for all sub-regions simultaneously. Fusing several good algorithms using a hierarchical majority vote yielded segmentations that consistently ranked above all individual algorithms, indicating remaining opportunities for further methodological improvements. The BRATS image data and manual annotations continue to be publicly available through an online evaluation system as an ongoing benchmarking resource.


Assuntos
Imageamento por Ressonância Magnética , Neuroimagem , Algoritmos , Benchmarking , Glioma/patologia , Humanos , Imageamento por Ressonância Magnética/métodos , Imageamento por Ressonância Magnética/normas , Neuroimagem/métodos , Neuroimagem/normas
17.
Proc Int World Wide Web Conf ; 2014: 405-406, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25844402

RESUMO

Instance checking is considered a central tool for data retrieval from description logic (DL) ontologies. In this paper, we propose a revised most specific concept (MSC) method for DL SHI, which converts instance checking into subsumption problems. This revised method can generate small concepts that are specific-enough to answer a given query, and allow reasoning to explore only a subset of the ABox data to achieve efficiency. Experiments show effectiveness of our proposed method in terms of concept size reduction and the improvement in reasoning efficiency.

19.
Stud Health Technol Inform ; 184: 20-3, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23400123

RESUMO

VCath is a neurosurgery training tool for the catheterization of the lateral ventricle that has been designed for use on tablet devices. We believe this is the first use of a tablet (iPad) for this purpose and demonstrates future utility for this approach, particularly for Objective Structured Clinical Exams (OSCEs). This paper outlines the implementation and use of VCath.


Assuntos
Cateterismo Cardíaco/métodos , Instrução por Computador/métodos , Computadores de Mão , Procedimentos Neurocirúrgicos/educação , Procedimentos Neurocirúrgicos/métodos , Cirurgia Assistida por Computador/métodos , Interface Usuário-Computador , Humanos , Tato
20.
Stud Health Technol Inform ; 184: 202-4, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23400156

RESUMO

Osteoarthritis of the hip is commonly caused by the repetitive contact between abnormal skeletal prominences between the anterosuperior femoral head-neck junction and the rim of the acetabular socket. Current methods for estimating femoroacetabular impingement by analyzing the sphericity of the femoral head require manual measurements which are both inaccurate and open to interpretation. In this research we provide a prototype software tool for improving this estimation.


Assuntos
Algoritmos , Impacto Femoroacetabular/diagnóstico por imagem , Imageamento Tridimensional/métodos , Interpretação de Imagem Radiográfica Assistida por Computador/métodos , Software , Tomografia Computadorizada por Raios X/métodos , Interface Usuário-Computador , Sistemas Computacionais , Humanos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
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