Dynamic multi feature-class Gaussian process models.

In model-based medical image analysis, three relevant features are the shape of structures of interest, their relative pose, and image intensity profiles representative of some physical properties. Often, these features are modelled separately through statistical models by decomposing the object's features into a set of basis functions through principal geodesic analysis or principal component analysis. However, analysing articulated objects in an image using independent single object models may lead to large uncertainties and impingement, especially around organ boundaries. Questions that come to mind are the feasibility of building a unique model that combines all three features of interest in the same statistical space, and what advantages can be gained for image analysis. This study presents a statistical modelling method for automatic analysis of shape, pose and intensity features in medical images which we call the Dynamic multi feature-class Gaussian process models (DMFC-GPM). The DMFC-GPM is a Gaussian process (GP)-based model with a shared latent space that encodes linear and non-linear variations. Our method is defined in a continuous domain with a principled way to represent shape, pose and intensity feature-classes in a linear space, based on deformation fields. A deformation field-based metric is adapted in the method for modelling shape and intensity variation as well as for comparing rigid transformations (pose). Moreover, DMFC-GPMs inherit properties intrinsic to GPs including marginalisation and regression. Furthermore, they allow for adding additional pose variability on top of those obtained from the image acquisition process; what we term as permutation modelling. For image analysis tasks using DMFC-GPMs, we adapt Metropolis-Hastings algorithms making the prediction of features fully probabilistic. We validate the method using controlled synthetic data and we perform experiments on bone structures from CT images of the shoulder to illustrate the efficacy of the model for pose and shape prediction. The model performance results suggest that this new modelling paradigm is robust, accurate, accessible, and has potential applications in a multitude of scenarios including the management of musculoskeletal disorders, clinical decision making and image processing.

The association between crawling as a first mode of mobilisation and the presentation of atraumatic shoulder instability: a retrospective cohort study.

BACKGROUND AND PURPOSE: To investigate if there is an association between whether an infant crawls as their first mode of mobilisation and the subsequent presentation of atraumatic shoulder instability. PATIENTS AND METHODS: A retrospective cohort of 50 consecutive patients who had presented to a national specialist centre for shoulder instability with a diagnosis of atraumatic instability was compared with a cohort of 50 participants who did not have shoulder instability. Primary outcomes were presence of atraumatic shoulder instability and whether or not the patient crawled as their first mode of mobility. A Pearson chi-squared test was used to evaluate associations. RESULTS: There was a significant association between crawling and shoulder instability (X 2(1) ≥ 11.93, p = 0.001) with a higher prevalence of non-crawlers in the group with shoulder instability compared to the control group. INTERPRETATION: There may be an association between developmental milestones and atraumatic shoulder instability. It cannot be concluded from this study whether association is causal and additional research is needed to further investigate this relationship. Asking patients presenting with shoulder instability about their developmental milestones as part of a full subjective history could guide a more targeted sensorimotor rehabilitation programme.

A user-centred design framework for mHealth.

BACKGROUND: Mobile health (mHealth) has the potential to improve access to healthcare, especially in developing countries. The proliferation of mHealth has not been accompanied by a corresponding growth in design guidelines for mHealth applications. This paper proposes a framework for mHealth application design that combines the Information Systems Research (ISR) framework and design thinking. We demonstrate a use case for the proposed framework in the form of an app to read the result of the tuberculin skin test (TST), which is used to screen for latent tuberculosis infection. The framework was used in the re-design of the TST reading app but could also be used in earlier stages of mHealth app design. METHODS: The ISR framework and design thinking were merged based on how the modes of design thinking integrate with the cycles of the ISR framework. Using the combined framework, we re-designed an mHealth app for TST reading, intended to be used primarily in a developing context by healthcare workers. Using the proposed framework, the app was iterated upon and developed with the aid of personas, observations, prototyping and questionnaires. RESULT: The combined framework was applied through engagement with end-users, namely ten healthcare workers and ten graduate students. Through review of the literature and iterations of the app prototype, we identified various usability requirements and limitations. These included challenges related to image capture and a misunderstanding of instructions. These insights influenced the development and improvement of the app. CONCLUSION: The combined framework allowed for engagement with end-users and for low-cost, rapid development of the app while addressing contextual challenges and needs. The integration of design thinking modes with the ISR cycles was effective in achieving the objectives of each approach. The combined framework acknowledges the importance of engaging users when implementing mHealth technologies, especially in developing and under-resourced contexts. Findings from this study support the use of this framework as a guide in the design of user-centred mHealth interventions.

Engaging Communities on Health Innovation: Experiences in Implementing Design Thinking.

Design thinking is an approach gaining momentum as a strategy for promoting empathy-driven, human-centered innovation. To evaluate the implementation of design thinking for engaging with communities about health and well-being, we undertook a qualitative analysis of an engagement between students and relevant community stakeholders during a project to develop a health intervention aimed at increasing medication compliance in an elderly community in South Africa. Major findings from this research indicated that design thinking offers opportunities for enriching community-university engagements. However, given constraints on time and procedure that are associated with the academy, the fast, dynamic style of design thinking is not optimally suited for developing the level of trust and rapport that is required for engagements in communities where social-cultural differences operate as barriers. Researchers who wish to utilize design thinking will need to devise and tailor additions to tool kits to meet the specific needs of engagements related to personal health and well-being.

Statistical shape-kinematics models of the skeletal joints: Application to the shoulder complex.

Patient-specific biomechanical simulations of joints require accurate reconstruction of bony anatomy from medical image data. The articular geometries of the joints may influence their biomechanics. Statistical shape models (SSMs) have become ubiquitous in the literature and aim to capture the natural variation of biological objects. They work by learning the variation from training examples to define the space of valid biological shapes. However, the kinematic information descriptive of the anato-physiological relationship of two interacting objects is not generally encoded in the SSM. Here, we propose a framework for developing combined statistical shape and kinematics models (SSKMs) as Gaussian process morphable models to analyse the shape and kinematics relationship. We demonstrate the framework on a three-dimensional (3D) image data set consisting of ten right-handed cadaveric shoulder joints acquired using computed tomography. Additionally, we simulate specific bone motions to encode kinematics in the combined model. Our SSKM built from shoulder data (matching scapulae and humeri) correctly depicts a correlation between the shape and kinematics as hypothesized. We furthermore demonstrate the ability to marginalize from the SSKM to obtain shape-only variation and kinematics-only variation. Future work aims to use the SSKM framework to understand the relationships between kinematics and shape for various joints as well as to develop patient-specific computational models to evaluate joint biomechanics.

Review of 2-D/3-D Reconstruction Using Statistical Shape and Intensity Models and X-Ray Image Synthesis: Toward a Unified Framework.

Patient-specific three-dimensional (3-D) bone models are useful for a number of clinical applications such as surgery planning, postoperative evaluation, as well as implant and prosthesis design. Two-dimensional-to-3-D (2-D/3-D) reconstruction, also known as model-to-modality or atlas-based 2-D/3-D registration, provides a means of obtaining a 3-D model of a patient's bones from their 2-D radiographs when 3-D imaging modalities are not available. The preferred approach for estimating both shape and density information (that would be present in a patient's computed tomography data) for 2-D/3-D reconstruction makes use of digitally reconstructed radiographs and deformable models in an iterative, non-rigid, intensity-based approach. Based on a large number of state-of-the-art 2-D/3-D bone reconstruction methods, a unified mathematical formulation of the problem is proposed in a common conceptual framework, using unambiguous terminology. In addition, shortcomings, recent adaptations, and persisting challenges are discussed along with insights for future research.

Nanomedicine for drug delivery in South Africa: a protocol for systematic review.

BACKGROUND: The emergence of nanomedicine in the past decade has changed the landscape of disease diagnosis and treatment. Nanomedicine makes use of nanostructures for applications in different fields of medicine, including drug delivery, biosensors, neuro-electronic interfaces, in vivo imaging, and cell-specific molecular interactions. Despite its relative infancy, nanomedicine has generated a significant body of research as evidenced by peer reviewed literature and several patents. This proposed systematic review will focus specifically on drug delivery systems in which nanoparticles are used to enhance the pharmacological and therapeutic properties of drugs. The strength of nanoparticulate drug delivery systems is their ability to alter the pharmacokinetics and bio-distribution of drugs. Globally, the discourse on nanomedicine is dominated by research being done in the developed countries of Europe and in the United States of America. Less attention has been given to the applications of nanomedicine in developing countries, particularly Africa. There is dearth of information on the applications of nanomedicine in terms of drug delivery with particular reference to which diseases are being targeted generally in Africa. The review will describe the specific diseases that are being targeted and the progress being made in South Africa, with a view to determining whether the applications of nanomedicine are being appropriated to address the context-specific challenges in this country or if they mimic what is being done globally. METHODS: Keywords related to nanomedicine and drug delivery will be combined to build a search strategy for each of the following databases: PubMed, Cochrane Library (including Cochrane Central Register of Controlled Trials (CENTRAL), Cochrane Database of Systematic Reviews, Cochrane Methodology Register), Google Scholar, NHS Health Technology Assessment Database and Web of Science. We will also check reference lists of included studies for other eligible reports and search unpublished data. To ensure that the search is comprehensive, grey literature will be searched extensively. Literature to be included will have nanomedicine in drug delivery as the primary application and report on the specific diseases that are targeted in South Africa. Two authors will independently screen the search output, select studies and extract data; discrepancies will be resolved by consensus and discussion. When no consensus is reached, the third author will be consulted DISCUSSION: The systematic review will inform the government, policy-makers, investors, health professionals, scientists, and engineers about the applications of nanomedicine in drug delivery. In particular, it will identify the diseases targeted by the application of nanomedicine for drug delivery and the progress being made in South Africa as the disease burden of this country differs from that of developed countries where nanomedicine has been widely used for drug delivery. SYSTEMATIC REVIEW REGISTRATION: PROSPERO CRD42017057388.

A modified stakeholder participation assessment framework for design thinking in health innovation.

Increasing pressure to improve health outcomes of populations with limited resources has prompted an emphasis on innovation. Design thinking has been proposed as a systematic approach to innovation in health, owing to its human-centred methodology that prioritises deep empathy for the end-users' desires, needs and challenges, which results in a better understanding of the problem in order to develop more comprehensive and effective solutions. A key feature of design thinking is stakeholder participation. If design thinking is going to be used as an approach to design and implement effective, equitable and sustainable health solutions, assessing stakeholder participation should be integrated into the process. Therefore, the purpose of this review is to i) provide an analysis of the literature on assessing stakeholder participation in health and ii) propose a framework based on the literature analysis that can be used to assess stakeholder participation during the design thinking process in health innovation. Drawing from participatory research in health, where stakeholder participation is recognised as a core principle that facilitates the implementation of solutions, we integrate stakeholder evaluation tools into the design thinking approach. We draw on an assessment framework that describes levels of stakeholder participation by their involvement in making decisions about their health. Using a 5-point continuum where the lower end represents the medical approach (professionals make all the decisions) and the upper end represents the community development approach (all stakeholders are key decision makers), we propose a modified assessment framework to evaluate stakeholder participation during the design thinking process. The modified framework provides a simple and practical tool to evaluate stakeholder participation. Stakeholders can rate their perceived level of participation, as well as that of the other stakeholders. Evaluation of participation in a design thinking project may be used to improve participation, and therefore the uptake and sustainability of innovations. The framework may also be used in design thinking beyond health applications.

Mobile phone-based evaluation of latent tuberculosis infection: Proof of concept for an integrated image capture and analysis system.

BACKGROUND: The tuberculin skin test is the most widely used method for detecting latent tuberculosis infection in adults and active tuberculosis in children. We present the development of a mobile-phone based screening tool for measuring the tuberculin skin test induration. METHOD: The tool makes use of a mobile application developed on the Android platform to capture images of an induration, and photogrammetric reconstruction using Agisoft PhotoScan to reconstruct the induration in 3D, followed by 3D measurement of the induration with the aid of functions from the Python programming language. The system enables capture of images by the person being screened for latent tuberculosis infection. Measurement precision was tested using a 3D printed induration. Real-world use of the tool was simulated by application to a set of mock skin indurations, created by a make-up artist, and the performance of the tool was evaluated. The usability of the application was assessed with the aid of a questionnaire completed by participants. RESULTS: The tool was found to measure the 3D printed induration with greater precision than the current ruler and pen method, as indicated by the lower standard deviation produced (0.3 mm versus 1.1 mm in the literature). There was high correlation between manual and algorithm measurement of mock skin indurations. The height of the skin induration and the definition of its margins were found to influence the accuracy of 3D reconstruction and therefore the measurement error, under simulated real-world conditions. Based on assessment of the user experience in capturing images, a simplified user interface would benefit wide-spread implementation. CONCLUSIONS: The mobile application shows good agreement with direct measurement. It provides an alternative method for measuring tuberculin skin test indurations and may remove the need for an in-person follow-up visit after test administration, thus improving latent tuberculosis infection screening throughput.

Open source modular ptosis crutch for the treatment of myasthenia gravis.

INTRODUCTION: Pharmacologic treatment of Myasthenia Gravis presents challenges due to poor tolerability in some patients. Conventional ptosis crutches have limitations such as interference with blinking which causes ocular surface drying, and frequent irritation of the eyes. To address this problem, a modular and adjustable ptosis crutch for elevating the upper eyelid in Myasthenia Gravis patients has been proposed as a non-surgical and low-cost solution. AREAS COVERED: This paper reviews the literature on the challenges in the treatment of Myasthenia Gravis globally and focuses on a modular and adjustable ptosis crutch that has been developed by the Medical Device Laboratory at the University of Cape Town. EXPERT COMMENTARY: The new medical device has potential as a simple, effective and unobtrusive solution to elevate the drooping upper eyelid(s) above the visual axis without the need for medication and surgery. Access to the technology is provided through an open source platform which makes it available globally. Open access provides opportunities for further open innovation to address the current limitations of the device, ultimately for the benefit not only of people suffering from Myasthenia Gravis but also of those with ptosis from other aetiologies.

The Impact of mHealth Interventions on Breast Cancer Awareness and Screening: Systematic Review Protocol.

BACKGROUND: Mobile health (mHealth) is the use of mobile communication technologies to promote health by supporting health care practices (eg, health data collection, delivery of health care information). mHealth technologies (such as mobile phones) can be used effectively by health care practitioners in the distribution of health information and have the potential to improve access to and quality of health care, as well as reduce the cost of health services. Current literature shows limited scientific evidence related to the benefits of mHealth interventions for breast cancer, which is the leading cause of cancer deaths in women worldwide and contributes a large proportion of all cancer deaths, especially in developing countries. Women, especially in low- and middle-income countries (LMICs), are faced with low odds of surviving breast cancer. This finding is likely due to multiple factors related to health systems: low priority of women's health and cancer on national health agendas; lack of awareness that breast cancer can be effectively treated if detected early; and societal, cultural, and religious factors that are prevalent in LMICs. The proposed systematic review will examine the impact of mHealth interventions on breast cancer awareness and screening among women aged 18 years and older. OBJECTIVE: The objectives of this study are to identify and describe the various mHealth intervention strategies that are used for breast cancer, and assess the impact of mHealth strategies on breast cancer awareness and screening. METHODS: Literature from various databases such as MEDLINE, EMBASE, PsycINFO, CINAHL, and Cochrane Central Register of Controlled Trials will be examined. Trial registers, reports, and unpublished theses will also be included. All mobile technologies such as cell phones, personal digital assistants, and tablets that have short message service, multimedia message service, video, and audio capabilities will be included. mHealth is the primary intervention. The search strategy will include keywords such as "mHealth," "breast cancer," "awareness," and "screening," among other medical subject heading terms. Articles published from January 1, 1964 to December 31, 2016 will be eligible for inclusion. Two authors will independently screen and select studies, extract data, and assess the risk of bias, with discrepancies resolved by dialogue involving a third author. We will assess statistical heterogeneity by examining the types of participants, interventions, study designs, and outcomes in each study, and pool studies judged to be statistically homogeneous. In the assessment of heterogeneity, a sensitivity analysis will be considered to explore statistical heterogeneity. Statistical heterogeneity will be investigated using the Chi-square test of homogeneity on Cochrane's Q statistic and quantified using the I-squared statistic. RESULTS: The search strategy will be refined with the assistance of an information specialist from November 1, 2017 to January 31, 2018. Literature searches will take place from February 2018 to April 2018. Data extraction and capturing in Review Manager (RevMan, Version 5.3) will take place from May 1, 2018 to July 31, 2018. The final stages will include analyses and writing, which is anticipated occur between August 2018 and October 2018. CONCLUSIONS: The knowledge derived from this study will inform health care stakeholders, including researchers, policy makers, investors, health professionals, technologists, and engineers, on the impact of mHealth interventions on breast cancer screening and awareness. TRIAL REGISTRATION: Prospero registration number CRD42016050202.

Towards understanding the drivers of policy change: a case study of infection control policies for multi-drug resistant tuberculosis in South Africa.

BACKGROUND: Explaining policy change is one of the central tasks of contemporary policy analysis. In this article, we examine the changes in infection control policies for multi-drug resistant tuberculosis (MDR-TB) in South Africa from the time the country made the transition to democracy in 1994, until 2015. We focus on MDR-TB infection control and refer to decentralised management as a form of infection control. Using Kingdon's theoretical framework of policy streams, we explore the temporal ordering of policy framework changes. We also consider the role of research in motivating policy changes. METHODS: Policy documents addressing MDR-TB in South Africa over the period 1994 to 2014 were extracted. Literature on MDR-TB infection control in South Africa was extracted from PubMed using key search terms. The documents were analysed to identify the changes that occurred and the factors driving them. RESULTS: During the period under study, five different policy frameworks were implemented. The policies were meant to address the overwhelming challenge of MDR-TB in South Africa, contextualised by high prevalence of HIV infection, that threatened to undermine public health programmes and the success of antiretroviral therapy rollouts. Policy changes in MDR-TB infection control were supported by research evidence and driven by the high incidence and complexity of the disease, increasing levels of dissatisfaction among patients, challenges of physical, human and financial resources in public hospitals, and the ideologies of the political leadership. Activists and people living with HIV played an important role in highlighting the importance of MDR-TB as well as exerting pressure on policymakers, while the mass media drew public attention to infection control as both a cause of and a solution to MDR-TB. CONCLUSION: The critical factors for policy change for infection control of MDR-TB in South Africa were rooted in the socioeconomic and political environment, were supported by extensive research, and can be framed using Kingdon's policy streams approach as an interplay of the problem of the disease, political forces that prevailed and alternative proposals.

Detecting Breast Cancer with a Dual-Modality Device.

Although mammography has been the gold standard for the early detection of breast cancer, if a woman has dense breast tissue, a false negative diagnosis may occur. Breast ultrasound, whether hand-held or automated, is a useful adjunct to mammography but adds extra time and cost. The primary aim was to demonstrate that our second-generation Aceso system, which combines full-field digital mammography (FFDM) and automated breast ultrasound (ABUS) in a single platform, is able to produce improved quality images that provide clinically meaningful results. Aceso was first tested using two industry standards: a Contrast Detail Mammography (CDMAM) phantom to assess the FFDM images, and the CIRS 054GS phantom to evaluate the ABUS images. In addition, 25 women participated in a clinical trial: 14 were healthy volunteers, while 11 were patients referred by the breast clinic at Groote Schuur Hospital. The CDMAM phantom results showed the FFDM results were better than the European Reference (EUREF) standard of "acceptable" and were approaching "achievable". The ABUS results showed a lateral and axial spatial resolution of 0.5 mm and an adequate depth penetration of 80 mm. Our second-generation Aceso system, with its improved quality of clinical FFDM and ABUS images, has demonstrated its potential for the early detection of breast cancer in a busy clinic.

The sociology of space as a catalyst for innovation in the health sector.

This paper reviews the role of space in facilitating innovation. It draws on the sociology of space in exploring the social practices, institutional forces and material complexity of how people and spaces interact. We assess how space influences the development of innovative solutions to challenges in the health sector. Our aim is to advance an understanding of the social production of space for healthcare innovation. We draw empirical examples from the Innovation Hub at Groote Schuur Hospital in Cape Town to illustrate that innovation does not take place in an institutional vacuum, but requires space that facilitates interaction of different players. This paper demonstrates that space matters in promoting innovation, particularly through its influence on social relationships and networks. An attractive and novel space, which is different from the usual workplace, stimulates innovation, mainly through being a base for the creation of an ecosystem for the productive interaction of different players. The interaction is important in inspiring new ideas, facilitating creative thought processes, maintaining the flow of information and bringing innovation to life.

The impact of mHealth interventions on health systems: a systematic review protocol.

BACKGROUND: Mobile health (mHealth) has been described as a health enabling tool that impacts positively on the health system in terms of improved access, quality and cost of health care. The proposed systematic review will examine the impact of mHealth on health systems by assessing access, quality and cost of health care as indicators. METHODS: The systematic review will include literature from various sources including published and unpublished/grey literature. The databases to be searched include: PubMed, Cochrane Library, Google Scholar, NHS Health Technology Assessment Database and Web of Science. The reference lists of studies will be screened and conference proceedings searched for additional eligible reports. Literature to be included will have mHealth as the primary intervention. Two authors will independently screen the search output, select studies and extract data; discrepancies will be resolved by consensus and discussion with the assistance of the third author. DISCUSSION: The systematic review will inform policy makers, investors, health professionals, technologists and engineers about the impact of mHealth in strengthening the health system. In particular, it will focus on three metrics to determine whether mHealth strengthens the health system, namely quality of, access to and cost of health care services. Systematic review registration: PROSPERO CRD42015026070.

Minimally invasive transcatheter aortic valve implantation for the treatment of rheumatic heart disease in developing countries.

INTRODUCTION: The treatment of rheumatic heart disease presents a medical and surgical challenge, particularly in developing countries, where the disease is prevalent. Most of these countries find it prohibitively expensive to import heart valve prostheses that are required for treatment and are largely manufactured in the United States and Europe. Even if the valves were available, the absence of facilities to conduct open-heart surgery for valve replacement results in many people from developing countries dying needlessly of the disease. To address this problem, transcatheter aortic valve implantation, an emerging, minimally invasive, treatment strategy for rheumatic heart disease, has been proposed. Areas covered: This paper reviews the literature on current valve technologies in use globally, and focuses on a minimally invasive transcatheter aortic valve implantation device and aortic valve prosthesis that have been developed by Strait Access Technologies Holdings in South Africa. Expert commentary: This new technology holds the potential of making available heart valve replacements to millions of patients in the developing world who would otherwise have no recourse to treatment.

Testing a dual-modality system that combines full-field digital mammography and automated breast ultrasound.

PURPOSE: The aim of this study was to test a novel dual-modality imaging system that combines full-field digital mammography (FFDM) and automated breast ultrasound (ABUS) in a single platform. Our Aceso system, named after the Greek goddess of healing, was specifically designed for the early detection of cancer in women with dense breast tissue. MATERIALS AND METHODS: Aceso was first tested using two industry standards: a Contrast Detail Mammography (CDMAM) phantom as endorsed by European Reference Organisation for Quality Assured Breast Screening and Diagnostic Services was used to assess the FFDM images; and the CIRS 040GSE ultrasound phantom was imaged to evaluate the quality of the ABUS images. In addition, 58 women participated in a clinical trial: 51 were healthy volunteers aged between 40 and 65, while 7 were patients referred by the breast clinic, 6 of whom had biopsy-proven breast cancer. RESULTS: The CDMAM tests showed that the FFDM results were "acceptable" but fell short of "achievable" which was attributed to the low dose used. The ABUS images had good depth penetration (80 mm) and adequate axial resolution (0.5 mm), but the lateral resolution of 2 mm was judged to be too coarse. In a 42-year-old volunteer with extremely dense breast tissue, the ABUS modality detected a lesion (a benign cyst) that was mammographically occult in the FFDM image. For a 73-year-old patient with fatty breasts, a malignant lesion was successfully detected and co-registered in the FFDM and ABUS images. On average, each woman spent less than 11 min in the acquisition room. CONCLUSIONS: While there is room for improvement in the quality of both the FFDM and ABUS images, Aceso has demonstrated its ability to acquire clinically meaningful images for a range of women with varying breast densities and, therefore, has potential as a screening device.