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Cardiogoniometry (CGM), a spatiotemporal electrocardiologic 5-lead method with automated analysis, may be useful in primary healthcare for detecting coronary artery disease (CAD) at rest. Our aim was to systematically develop a stenosis-specific parameter set for global CAD detection. In 793 consecutively admitted patients with presumed non-acute CAD, CGM data were collected prior to elective coronary angiography and analyzed retrospectively. 658 patients fulfilled the inclusion criteria, 405 had CAD verified by coronary angiography; the 253 patients with normal coronary angiograms served as the non-CAD controls. Study patients--matched for age, BMI, and gender--were angiographically assigned to 8 stenosis-specific CAD categories or to the controls. One CGM parameter possessing significance (P < .05) and the best diagnostic accuracy was matched to one CAD category. The area under the ROC curve was .80 (global CAD versus controls). A set containing 8 stenosis-specific CGM parameters described variability of R vectors and R-T angles, spatial position and potential distribution of R/T vectors, and ST/T segment alterations. Our parameter set systematically combines CAD categories into an algorithm that detects CAD globally. Prospective validation in clinical studies is ongoing. [ABSTRACT FROM AUTHOR]

Objectives: To review recent research efforts in the field of ubiquitous computing in health care. To identify current research trends and further challenges for medical informatics.Methods: Analysis of the contents of the Yearbook on Medical Informatics 2005 of the International Medical Informatics Association (IMIA).Results: The Yearbook of Medical Informatics 2005 includes 34 original papers selected from 22 peer-reviewed scientific journals related to several distinct research areas: health and clinical management, patient records, health information systems, medical signal processing and biomedical imaging, decision support, knowledge representation and management, education and consumer informatics as well as bioinformatics. A special section on ubiquitous health care systems is devoted to recent developments in the application of ubiquitous computing in health care. Besides additional synoptical reviews of each of the sections the Yearbook includes invited reviews concerning E-Health strategies, primary care informatics and wearable healthcare.Conclusions: Several publications demonstrate the potential of ubiquitous computing to enhance effectiveness of health services delivery and organization. But ubiquitous computing is also a societal challenge, caused by the surrounding but unobtrusive character of this technology. Contributions from nearly all of the established sub-disciplines of medical informatics are demanded to turn the visions of this promising new research field into reality. [ABSTRACT FROM AUTHOR]

Objectives: To summarize the challenges facing clinical applications in the light of growing research results in genomic medicine and bioinformatics.Methods: Analysis of the contents of the Yearbook of Medical Informatics 2004 of the International Medical Informatics Association (IMIA).Results: The Yearbook of Medical Informatics 2004 includes 32 articles selected from 22 peer-reviewed scientific journals. A special section on clinical bioinformatics highlights recent developments in this field. Several guest editors review the promises and limitations of available methods and resources from biomedical informatics that are relevant to clinical medicine. Integrated data and knowledge resources are generally regarded to be central and key issues for clinical bioinformatics. Further review papers deal with public health implications of bioinformatics, knowledge management and trends in health care education. The Yearbook includes for the first time a section on the history of medical informatics, where the significant impact of the Reisensburg protocol 1973 on international health and medical informatics education is examined.Conclusions: Close collaboration between bioinformatics and medical informatics researchers can contribute to new insights in genomic medicine and contribute towards the more efficient and effective use of genomic data to advance clinical care. [ABSTRACT FROM AUTHOR]

Many heart diseases result in or from abnormal atrium and/or ventricle motion; therefore, analysis of shape changes due to heart motion is crucial to diagnostic classification. This paper aimed at investigating the suitability of a medial-based modeling approach to fulfill the task of representing and analyzing the right atrium and ventricle motion during the cardiac cycle. We analyzed the heart of one subject within a cardiac cycle covering 11 different time steps. Based on shape correspondence of the medial method, a common shape model for the object ensemble was generated for the complete cardiac cycle. The time-dependent variations were analyzed using an extended PCA method showing that almost 90% of variations due to cardiac motion are covered within the first three modes. The promising results highlight the method''s value in quantifying shape changes during the cardiac cycle for healthy and for clinical relevant populations. [Copyright &y& Elsevier]

Analysis of shape variability of anatomical structures is a widespread problem on one hand and an essential fundament for the analysis of biological processes and the diagnosis of a large spectrum of pathologies on the other hand. Many diseases affecting the middle ear result from morphological alterations and provoke morphological changes of the middle ear cavity. Therefore, it was our goal to analyze shape and shape variations of a population of this anatomical structure.By segmenting and modeling 10 middle ear cavities using a medial-based representation, which provides inter-individual correspondence, a common shape model of the tympanic cavity has been generated. The results show that medial-based representation is suitable to generate a common shape model of the tympanic cavity and to provide a facility to analyze the complex shape of the anatomical structure and the physiological variations. [Copyright &y& Elsevier]

Objective: This study aims to examine the type of involvement of patient companions in the argumentative exchanges in consultations and explore when their contributions should be taken into account in shared decision-making (SDM)., Methods: A qualitative analysis was carried out using transcribed medical consultations (N = 10) between health professionals (doctors at a regional Dutch hospital), adult patients and informal patient companions. Insights from argumentation theory were used to develop an inventory of twelve theoretically distinct discussion situations involving patient companions, distinguishing possible discussion roles, disagreement types and coalition formations., Results: Consultations contained on average 4.3 discussion situations. In most discussions (37.21 %) the health professional adopted a standpoint, and the patient and their companion only expressed doubt. More complex cases occurred when one of the three parties, including the companion, opposed opinions of the other parties (in 34.88 % of the situations found) and when coalitions were formed (possible in 18.60 % of the situations found). We found that disagreements occurred or were anticipated by all three parties and involved standpoints about the diagnosis as well as treatment options., Conclusion: Using the pragma-dialectical argumentation theory as an analytical framework reveals that patient companions can substantially influence treatment decision-making during medical consultation. This influence is contingent upon the specific role they assume in the discussion, the type of disagreement with the health professional and patient, and the formation of coalitions with these parties., Practice Implications: The contributions by patient companions should be considered in SDM if the companion forms a coalition with the patient. If the companion does not form a coalition, the contributions might have a bearing on SDM as well, but their acceptability and relevance for the treatment decision should be checked by the health professional. In general, it is desirable to explicitly establish the role of patient companions in consultations., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Authors. Published by Elsevier B.V. All rights reserved.)

Functional MRI (fMRI) utilizes changes in metabolic and hemodynamic signals to indirectly infer the underlying local changes in neuronal activity. To investigate the mechanisms of fMRI responses, spontaneous fluctuations, and functional connectivity in the resting-state, it is important to pursue fMRI in animal models. Animal studies commonly use dexmedetomidine sedation. It has been demonstrated that potent sensory stimuli administered under dexmedetomidine are prone to inducing seizures in Sprague-Dawley (SD) rats. Here we combined optical imaging of intrinsic signals and cerebral blood flow with neurophysiological recordings to measure responses in rat area S1FL to electrical forepaw stimulation administered at 8 Hz. We show that the increased susceptibility to seizures starts no later than 1 h and ends no sooner than 3 h after initiating a continuous administration of dexmedetomidine. By administering different combinations of anesthetic and sedative agents, we demonstrate that dexmedetomidine is the sole agent necessary for the increased susceptibility to seizures. The increased susceptibility to seizures prevails under a combination of 0.3-0.5% isoflurane and dexmedetomidine anesthesia. The blood-oxygenation and cerebral blood flow responses to seizures induced by forepaw stimulation have a higher amplitude and a larger spatial extent relative to physiological responses to the same stimuli. The epileptic activity and the associated blood oxygenation and cerebral blood flow responses stretched beyond the stimulation period. We observed seizures in response to forepaw stimulation with 1-2 mA pulses administered at 8 Hz. In contrast, responses to stimuli administered at 4 Hz were seizure-free. We demonstrate that such seizures are generated not only in SD rats but also in Long-Evans rats, but not in C57BL6 mice stimulated with similar potent stimuli under dexmedetomidine sedation. We conclude that high-amplitude hemodynamic functional imaging responses evoked by peripheral stimulation in rats sedated with dexmedetomidine are possibly due to the induction of epileptic activity. Therefore, caution should be practiced in experiments that combine the administration of potent stimuli with dexmedetomidine sedation. We propose stimulation paradigms that elicit seizure-free, well detectable neurophysiological and hemodynamic responses in rats. We further conclude that the increased susceptibility to seizures under dexmedetomidine sedation is species dependent., (Copyright © 2020 Bortel, Pilgram, Yao and Shmuel.)

Semantic feature norms (e.g., STIMULUS: car → RESPONSE: ) are commonly used in cognitive psychology to look into salient aspects of given concepts. Semantic features are typically collected in experimental settings and then manually annotated by the researchers into feature types (e.g., perceptual features, taxonomic features, etc.) by means of content analyses-that is, by using taxonomies of feature types and having independent coders perform the annotation task. However, the ways in which such content analyses are typically performed and reported are not consistent across the literature. This constitutes a serious methodological problem that might undermine the theoretical claims based on such annotations. In this study, we first offer a review of some of the released datasets of annotated semantic feature norms and the related taxonomies used for content analysis. We then provide theoretical and methodological insights in relation to the content analysis methodology. Finally, we apply content analysis to a new dataset of semantic features and show how the method should be applied in order to deliver reliable annotations and replicable coding schemes. We tackle the following issues: (1) taxonomy structure, (2) the description of categories, (3) coder training, and (4) sustainability of the coding scheme-that is, comparison of the annotations provided by trained versus novice coders. The outcomes of the project are threefold: We provide methodological guidelines for semantic feature classification; we provide a revised and adapted taxonomy that can (arguably) be applied to both concrete and abstract concepts; and we provide a dataset of annotated semantic feature norms.

A solid and accurate proximal femur segmentation technique using the popular active shape model (ASM) is proposed. For generating an optimal shape prior, the minimum description length, based on 200 supervised manual segmented proximal femur shapes, is used. The segmentation is based on a coarse to fine scaling technique including a profile scale space method. The segmentation results are compared using an optimal defined initial pose and a pose based on a registration technique. Using ideal template initialization, 95% of the shapes have been recovered exactly (average point-to-point error approximately 13 pixels, average point-to-boundary error approximately 7 pixels). Using a template-based initialization based on a registration technique, a successful segmentation rate of approximately 89% is achieved, with an average point-to-point error approximately 12 pixels, and an average point-to-boundary error approximately 8 pixels. With an adequate template initialization and an improved ASM, this method seems to provide an accurate tool for segmentation of the proximal femur shapes on conventional hip overview x-ray images.

In this paper we present a knowledge-based femur detection algorithm. The algorithm uses femur corpus constraints, Canny edge detection and Hough lines. For optimal femur template placement in the local area we use cross-correlation. The segmentation itself is done with an optimized active shape modeling technique. Using the knowledge-based technique we have located 95% of the femur shapes of N=117 X-rays. From those 83% of the target femur shapes have been segmented successfully (point-to-point error: approximately 14 pixels, point-to-boundary error = approximately 9 pixels).