Technology and Health Care - Volume 12, issue 1

Authors: Tu, Chengyuan | Zeng, Yanjun | Yang, Xinchun

Article Type: Research Article

Abstract: A new approach based on a histogram analysis to detect QRS-T complexes of the ECG curve rapidly and reliably is described. The aim consists of a rapid and reliable detection of the P-wave (when atrial fibrillation, AF, is absent) or the f-wave (when AF happens). By means of signal processing techniques such as the fractal dimension method and the Shannon entropy method, two types of ECG signals (with or without AF) were analysed and the significant differences between them documented. Accordingly, the methods allow to determine easily whether AF occurs or not.

Keywords: ECG curve, P-wave, f-wave, AF (atrial fibrillation), histogram, fractral dimension, Shannon entropy

DOI: 10.3233/THC-2004-12101

Citation: Technology and Health Care, vol. 12, no. 1, pp. 1-9, 2004

Authors: Wijaya, Sastra Kusuma | Sumikawa, Takuya | Saratani, Keiji | Kawazoe, Takayoshi | Oka, Hisao

Article Type: Research Article

Abstract: This study aimed at developing a dental implant movement (IM) checker for assessing quantitative dental implant mobility. The design of the instrument was based on the tooth mobility (TM) tester, which was previously developed by our group. The IM checker consists of a newly developed measuring probe which has the size of a typical dental drill so that it would be easy to measure at all regions of dental implants. The probe has a bimorph ceramics transducer for actuating an implant at constant frequency and force amplitude and for detecting acceleration response. A set of strain gauges were attached to …the bimorph ceramics for detecting preload during measurement. A new digital data acquisition system was used to eliminate measurement artifacts mainly due to probe handling. The IM checker could discriminate the artificial dental implant models in the range of clinical tooth mobility M0 with variation less than 6%. The measuring time needed by five operators was less than 15 s. Accordingly, the IM checker has sufficient measuring reliability and therefore it could be introduced in dental clinics. Show more

Keywords: tooth mobility, dental implant, mechanical mobility, manual examination

DOI: 10.3233/THC-2004-12102

Citation: Technology and Health Care, vol. 12, no. 1, pp. 11-23, 2004

Authors: Müller, Matthias | Schirm, Simon | Teschner, Matthias

Article Type: Research Article

Abstract: In this paper, we propose an interactive method based on Smoothed Particle Hydrodynamics (SPH) to simulate blood as a fluid with free surfaces. While SPH was originally designed to simulate astronomical objects, we gear the method towards fluid simulation by deriving the force density fields directly from the Navier-Stokes equation and by adding a term to model surface tension effects. In contrast to Eulerian grid-based approaches, the particle-based approach makes mass conservation equations and convection terms dispensable which reduces the complexity of the simulation. In addition, the particles can directly be used to render the surface of the fluid. Our …method can be used in interactive surgical training systems with models of up to 3000 particles. Show more

DOI: 10.3233/THC-2004-12103

Citation: Technology and Health Care, vol. 12, no. 1, pp. 25-31, 2004

Authors: Boulos, Maged N. Kamel

Article Type: Research Article

Abstract: HealthCyberMap (http://healthcybermap.semanticweb.org ) is a Semantic Web project that aims at mapping selected parts of health information resources in cyberspace in novel semantic ways to improve their retrieval and navigation. This paper describes HealthCyberMap semantic subject search engine methodology and early prototype which attempt to overcome the limitations of conventional free text search engines. Explicit concepts in resource metadata map onto a brokering domain ontology (a clinical terminology or classification) allowing a Semantic Web search engine to infer implicit meanings (synonyms and semantic relationships) not directly mentioned in either the resource or its metadata. Similarly, user queries would map to …the same ontology allowing the search engine to infer the implicit semantics of user queries and use them to optimise retrieval. Related issues of metadata, clinical terminologies and automatic vs. manual indexing of medical Web resources are also discussed, together with future methodological directions, which include the use of a true terminology server as an intelligent broker between user queries and HealthCyberMap pool of resource metadata. A comparative evaluation of the new engine based on relevance metrics is also proposed. Show more

Keywords: clinical terminologies for medical resource indexing, medical metadata, medical semantic search engine, medical information retrieval, medical Semantic Web

DOI: 10.3233/THC-2004-12104

Citation: Technology and Health Care, vol. 12, no. 1, pp. 33-41, 2004

Authors: Schmitt, K.-U. | Spierings, A.B. | Derler, S.

Article Type: Research Article

Abstract: The potential of hip protectors to prevent femur fracture is addressed in this study. A mechanical model of the human hip was developed and used to perform impact tests with different types of hip protectors. In addition a finite element model of the test device was established which allows simulations of the impact tests. The different principles of energy-shunting systems and energy-absorbing systems were demonstrated. Furthermore misplacement of a hip protector can be simulated. Hence the FE model was shown to be a suitable tool for future hip protector design.

DOI: 10.3233/THC-2004-12105

Citation: Technology and Health Care, vol. 12, no. 1, pp. 43-49, 2004

Authors: Pandit, Abhay S. | Henry, Jerome A.

Article Type: Research Article

Abstract: There is an increasing use of meshes to surgically repair or reconstruct anatomical defects. The surgical mesh firmly augments the debilitated area, provides a tension-free repair and facilitates the incorporation of fibrocollagenous tissue into the surgical mesh. However, the variant of mesh that facilitates best surgical practice is controversial. Surgical meshes have been predominantly designed with greater emphasis being placed on enhancing the biocompatibility of surgical meshes rather than on the engineering parameters. There is abundant evidence indicating a relationship between post-operative complications and the mesh design. Yet, the design of surgical meshes from an engineering perspective has to come …to fruition. This article endeavours to present a synopsis of the current state of the science of surgical meshes, their clinical applications and the current trends in research. Show more

Keywords: surgical meshes, scaffold, repair, reconstruction

DOI: 10.3233/THC-2004-12106

Citation: Technology and Health Care, vol. 12, no. 1, pp. 51-65, 2004

Authors: Ghunaimi, Bader Al | Hossen, Abdulnasir | Hassan, Mohammed O.

Article Type: Research Article

Abstract: A new technique of time-domain analysis for screening of Obstructive Sleep Apnea (OSA) using R-R interval (RRI) data is investigated. This method is based on the Statistical Signal Characterization (SSC) of the analytical signal that is generated using Hilbert transformation of the RRI data. The four SSC parameters: amplitude mean, period mean, amplitude deviation and period deviation, and their maximum and minimum values are found over a 5-minutes sliding window for both the instantaneous amplitudes and the instantaneous frequencies derived from the analytical signal of the RRI data. Data used in this work are drawn from both MIT database as …well as from the Sleep Laboratory at Sultan Qaboos University (SQU) hospital. Threshold values used in the identification of OSA from normal subjects are selected using the Receiver Operating Characteristics (ROC) curves. The new technique classifies correctly 29/30 of MIT Trial data, 27/30 of MIT challenge data, and 30/30 of SQU data. Show more

Keywords: statistical signal characterization, obstructive sleep apnea, hilbert transform, heart rate variability, time-domain analysis

DOI: 10.3233/THC-2004-12107

Citation: Technology and Health Care, vol. 12, no. 1, pp. 67-78, 2004