Conference Papers

The Presence of Regional Accents in Electrolarynx Speech and the Resultant Effect on Overall Intelligibility.

Brian Madden et al. — Wed, 12 Sep 2012 04:10:29 PDT

During voiced speech, the larynx provides quasi-periodic acoustic excitation of the vocal tract. In most electrolarynxes, mechanical vibrations are produced by a linear electromechanical actuator, the armature of which percusses against a metal or plastic plate at a frequency within the range of glottal excitation. In this paper, a phonological analysis of a section of results from an online perceptual intelligibility test was performed which compared speech produced using a novel hands-free electrolarynx and a commercially available electrolarynx. A portion of the test consisted of a closed-set format containing a selection of four sets of four random CVC audio samples (recorded by two speakers - 1 male, 1 female - using the Servox™ and the hands-free pager motor design). Each survey participant was requested to listen to every recording and then choose the word they thought most closely resembled the recording in which they heard. The phenomenon referred to as Irish-English, as documented by Hickey [1], highlights the historical development of the English language and how its pronunciation currently varies throughout the country. The two speakers used in the intelligibility test originated from two phonologically contrasting regions – a male from the East and a female from the West. These differences are analysed with the aid of findings by Hickey and assessed as to whether they could potentially improve or hinder the intelligibility of an utterance.

A Wireless and Digital Electrode Bus Topology for Biopotential Measurement

Mark Nolan et al. — Thu, 26 Jul 2012 00:56:07 PDT

The conventional biopotential measurement configuration utilises long lead wires which connect measuring electrodes to signal conditioning circuitry. The majority of bioelectric signals that are measured from the human body have a tiny signal amplitude (5µV-5mV range) and thus any interference that is induced on the lead wires can have a detrimental effect on the original signal. In this paper, we present an alternative configuration, in which digitisation occurs on the electrode, potentially providing enhanced signal measurement as well as significant benefits in terms of the simplification of the physical interconnections between electrodes. Multiple electrodes are combined to form a digital electrode bus. This proposed topology represents the next stage in the evolution of bioelectric measurement as, due to the decrease in cost and size of integrated circuits, more of the bioinstrumentation circuitry is shifted away from a base measurement station and into the electrode itself. The prototype wireless device outlined in this paper consists of a grid of electrode nodes. By adding a circuit weighing less than 0.45g and with a diameter of 1.5cm to standard button clip electrodes, each node contains a high resolution analog-to-digital converter, and a microcontroller. With this design, the lead length has been reduced to a copper PCB track with dimensions of less than 3.5x0.3mm. All of the nodes are connected onto a shared I2C bus on which a master node synchronises slave electrode sampling and coordinates inter-device communication. The system is currently capable of a 215 Hz sampling rate (for one node at 16-bit resolution) with a limit of up to 79 nodes connected. The system has been demonstrated to work on the electrooculogram and the electrocardiogram and the results for these have been outlined.

Performance Analysis and Assessment of a TF-IDF Based Archetype-SNOMED-CT Binding Algorithm

Sheng Yu et al. — Wed, 26 Oct 2011 01:17:55 PDT

Term bindings in archetypes are at a boundary between health information models and health terminology for dual model-based electronic health-care record (EHR) systems. The development of archetypes and the population of archetypes with bound terms is in its infancy. Terminological binding is currently performed “manually” by the teams who create archetypes. This process could be made more efficient, if it was supported by automatic tools. This paper presents a method for evaluating the performance of automatic code search approaches. In order to assess the quality of the automatic search, the authors extracted all the unique bound codes from 1133 archetypes from an archetype repository. These “manually bound ”SNOMED-CT codes were compared against the codes suggested by the authors' automatic search and used for assessing the algorithm's performance in terms of accuracy and category matching. The result of this study shows a sensitivity analysis of a set of parameters relevant to the matching process.

An Analysis Framework for Electronic Health Record Systems

Jesus Bisbal et al. — Wed, 19 Jan 2011 06:42:58 PST

Background: The timely provision of complete and up-to-date patient data to clini-cians has for decades been one of the most pressing objectives to be fulfilled by infor-mation technology in the healthcare domain. The so-called e lectronic health record (EHR), which provides a unified view of all relevant clinical data, has received much attention in this context from both research and industry. This situation has given rise to a large number of research projects and commercial products that aim to address this challenge. Different projects and initiatives have attempted to address this challenge from various points of view, which are not easily comparable. Objectives: This paper aims to clarify the challenges, concepts, and approaches in-volved, which is essential in order to consistently compare existing solutions and objec-tively assess progress in the field. Methods: This is achieved by two different means. Firstly, the paper will identify the most significant issues that differentiate the points of view and intended scope of existing approaches. As a result, a framework for analysis of EHR systems will be produced. Secondly, the most representative EHR-related projects and initiatives will be described and compared within the context of this framework. Results: The main result of the present paper is an analysis framework for EHR systems. This is intended as an initial step towards an attempt to structure research on this field, clearly lacking sound principles to evaluate and compare results, and ultimately focusing its efforts and being able to objectively evaluate scientific progress. Conclusions: Evaluation and comparison of results in medical informatics, and specifically EHR systems, must address technical and non-technical aspects. It is challenging to condensate in a single framework all potential views of such a field, and any chosen approach is bound to have its limitations. That being said, any well structured comparison approach, such as the framework presented here, is better than no comparison framework at all, as has been the current situation to date. This paper has presented the first attempt known to the authors to define such a framework.

Archetype alignment: A two-level driven semantic matching approach to interoperability in the clinical domain

Damon Berry et al. — Tue, 18 Jan 2011 04:45:07 PST

Semantic interoperability between electronic health record systems and other information systems in the health domain implies agreement about the structure and the meaning of the information that is communicated. There are still a number of similar but different EHR system approaches. Some of the newer approaches adopt the two-layer model approach where a generic reference model is constrained by archetypes into valid clinical concepts which can be exchanged. The meaning of the concepts that are represented by an archetype can be conveyed by embedding codes from a commonly recognised terminology at appropriate points in the archetype. However, as the number of archetypes multiply it will become necessary to match archetypes from different sources to facilitate interoperability. This paper describes an approach that supports semantic interoperability between heterogeneous two-level health information systems by identifying similarities between archetypes. The approach identifies relationships between ontological terms which have been embedded in pairs of archetypes as a means of matching these terms. The matched terms can then in turn be used to identify similarities between archetypes. The limited contextual scope of an archetype simplifies this matching process.

A Mobile ECG Monitoring System with Context Collection

Jin Peng Li et al. — Mon, 17 Jan 2011 08:38:54 PST

Preventative health management represents a shift from the traditional approach of reactive treatment-based healthcare towards a proactive wellness-management approach where patients are encouraged to stay healthy with expert support when they need it, at any location and any time. This work represents a step along the road towards proactive, preventative healthcare for cardiac patients. It seeks to develop a smart mobile ECG monitoring system that requests and records context information about what is happening around the subject when an arrhythmia event occurs. Context information about the subject’s activities of daily living will, it is hoped, provide an enriched data set for clinicians and so improve clinical decision making. As a first step towards a mobile cardiac wellness guideline system, the authors present a system which can receive bio-signals that are wirelessly streamed across a body area network from Bluetooth enabled electrocardiographs. The system can store signals as they arrive while also responding to significant changes in Electrocardiogram activity. The authors have developed a prototype on a handheld computer that detects and responds to changes in the calculated heart rate as detected in an ECG signal. Although the general approach taken in this work could be applied to a wide range of bio-signals, the work focuses on ECG signals. The components of the system are, - A Bluetooth receiver, data collection and storage module - A real-time ECG beat detection algorithm. - An Event-Condition-Action (E-CA) rule base which decides when to request context information from the user. – A simple user interface which can request additional information from the user. A selection of real-time ECG detection algorithms were investigated for this work and one algorithm was tested in MATLAB and then implemented in Java. In order to collect ECG signals (and in principle any signals), the generalised data collection architecture has also been developed using Java and Bluetooth technology. An Event-Condition-Action (ECA) rule based expert system evaluates the changes in heart beat interval to decide when to interact with the user to request context information.

Attitudes of Health Professionals to Electronic Data Sharing within an Integrated Care Electronic Health Record (ICEHR)

Charyl O'Malley et al. — Mon, 17 Jan 2011 08:38:52 PST

It is estimated that 98,000 people die in hospitals yearly in the USA as a result of medical errors (Agency for Healthcare Research and Quality, 2009). Electronic Health Records (EHR) can offer improved patient safety. EHRs are being implemented by many countries, however, not all health professionals have welcomed them (MORI Social Research Institute, 2006). As outlined in the National Health Information Strategy (NHIS) document, Ireland has plans to introduce an EHR. Attitudes of health professionals are a significant factor for the successful implementation and adoption of a new clinical information system. This study aimed to gauge the attitude of health professionals in Ireland to electronic data sharing within an integrated care electronic health record (ICEHR). A questionnaire identified attitudes of health professionals in Ireland to EHRs. This resulted in the majority supporting the introduction of an ICEHR system and indicating patient care and safety as the reasons for their support. They believed patient care, communications, data quality and work practices would be improved as a result. Most were in favour of the introduction of a Unique Health Identifier (UHI). Many respondents indicated that they believe patient confidentiality could be jeopardised due to electronically sharing detailed patient clinical information. Internal threats to the organisation, staff inappropriately accessing patient information, and external threats, such as hackers or insurance companies, were a concern. Many respondents reported that they would use the clinical information from an ICEHR system. Their experiences with similar recently implemented systems have left them with a very positive attitude.

An Investigation of the use of a High Resolution ADC as a Digital Biopotential Amplifier

Damon Berry et al. — Mon, 17 Jan 2011 08:38:50 PST

Sigma delta analogue to digital converters have been used in many signal processing applications including some commercially available systems for sampling of bio-signals Bio-potential amplifiers have traditionally utilised specialised highquality analogue components to amplify bio-signals.

The central aim of this work is to investigate the benefits of using high-resolution sigma delta conversion as a digital amplification stage in the signal path of a bio-potential amplifier. A number of system arrangements specific to bio-potential measurement are presented and discussed. These arrangements are designed to use the high resolution capacity of the sigma delta converter in different ways, providing different benefits. To explore these benefits, the authors have implemented a digital bio-potential signal capture system consisting of a sigma delta converter interfaced to a PC running MATLAB via an inexpensive microcontroller and to test it with a number of test signals.

A signal generator which simulates the attributes of an Electrocardiogram was used together with analogue signal conditioning for two electrode and three electrode measurement to provide suitable signal sources for capture using the digital bioamplifier. The results were analysed to investigate the trade off between signal resolution and analogue amplification.

Novel Bioelectrical Measurement using a Digital Biopotential Monode

Mark Nolan et al. — Fri, 14 Jan 2011 07:53:13 PST

In conventional biopotential recording, two or more electrodes are placed on the body. A unipolar lead records the time-varying electrical potential at a single point (relative to a reference potential) via one signal electrode. A bipolar lead records the time-varying potential difference between two points via two signal electrodes. In each case, the signal electrodes are connected to high impedance amplifier inputs, while an additional electrode provides a low-impedance path between the amplifier and human subject.

Bipolar leads are usually preferred since interference appearing at both signal electrodes can be eliminated using an instrumentation amplifier with high CMRR. A drawback of bipolar lead recording is that wires must connect all electrodes to the amplifier. This paper presents preliminary work on a novel design for a digital biopotential measurement device which we call the biopotential monode.

Identity Management to Support Access Control in E-Health Systems

Xu Chen et al. — Fri, 14 Jan 2011 03:25:05 PST

The related and often challenging topics of identity management and access control form an essential foundation for e-health infrastructure. Several approaches and supporting specifications for electronic healthcare record system (EHR-S) communication have been proposed by research projects and standards development organizations in recent years. For instance, part four of the CEN TC251 EN13606 EHRcom standard and the HL7 Role Based Access Control Draft Standard for Trial Use have helped to specify the nature of access control behaviour in relation to EHR communication within and between healthcare organisations. Access control services are a core component not only of the integrated care EHR-S but also for other information systems in the e-health domain. To underpin functionality of this type in a distributed environment, it is necessary to provide access to scalable, secure and uniform ID domains for users and patients.

This paper considers the use of part four of the EHRcom standard in the context of the availability (or lack thereof) of national identification systems for patients and for users of an integrated care EHR-S. This work begins with a brief summary of the state-of-the-art in identity management and access control in the health domain and a description of approaches that could lead to a secure and interoperable identification mechanism. To address the identification problem, the authors describe well known EHR access control viewpoints that are compatible with the CEN standard for EHR communication, EN13606 and describe how an identification service can support this functionality.

On Improving Electrooculogram-based Computer Mouse Systems: the Accelerometer Trigger

Johnalan Keegan et al. — Fri, 14 Jan 2011 02:35:47 PST

Eye tracking is a well-established method of computer control for profoundly paralysed people (Anson et al., 2002). Cameras are commonly used to track eye

movements (Morimoto et al., 2005) but one alternative is the bioelectrical signal known as the electrooculogram (EOG).

There are some EOG mouse control systems that facilitate the use of GUI applications, but certain actions, which are straightforward using a conventional mouse, remain impossible. Unless the eyes are tracking a target, they move in saccades

(jumps), making it impossible to voluntarily trace out smooth trajectories with one's gaze, as would be required to draw a smooth curve.

The conventional paradigm for EOG mouse control maps horizontal and vertical angular displacement of the eyes onto the coordinates of the mouse pointer (Gips et al. and Estrany et al., 2008), while the head remains stationary. Reversing this paradigm, if the

point of fixation remains unchanged, the EOG can measure head movement. The present system adopts this approach, mapping smooth, saccade-free head movement onto mouse pointer movement, while the

gaze remains fixed on a point that is either stationary or moving smoothly (e.g. the mouse pointer). Because the eyes move in pursuit mode rather than in saccades, smooth mouse control is possible. Voltage drift, which arises due to changing electrode junction voltages, poses a serious problem for EOG-based mouse control. In this paper we show how an accelerometer can be used to mitigate the effect of voltage drift.

Augmented control of a hands-free electrolarynx

Brian Madden et al. — Thu, 13 Jan 2011 07:20:25 PST

During voiced speech, the larynx acts as the sound source, providing a quasi-periodic excitation of the vocal tract. Following a total laryngectomy, some people speak using an electrolarynx which employs an electromechanical actuator to perform the excitatory function of the absent larynx. Drawbacks of conventional electrolarynx designs include the monotonic sound emitted, the need for a free-hand to operate the device, and the difficulty experienced by many laryngectomees in adapting to its use. One improvement to the electrolarynx, which clinicians and users frequently suggest, is the provision of a convenient hands-free control facility. This would allow more natural use of body language, as well as enabling the user to perform other manual tasks whilst speaking. An additional enhancement is the redevelopment of the devices' actuator to remove the self-radiated buzzing sound which is emitted during operation. The overall goal of this research is to investigate the implementation of a more natural sounding, hands-free electrolarynx, with an activation method which uses accelerometers that are placed on the chest and abdomen to detect torso based breathing prior to the initiation of speech. Results illustrate from intelligibility tests carried out that the speech produced using our novel actuator is substantially more intelligible to all the listeners than that produced using the conventional electrolarynx. Also, the abrupt change in breathing pattern which occurs at the onset of speech is clearly observable in signals recorded by the accelerometers, facilitating a possible automatic activation of an electro-larynx which will be investigated further in user trials.

Design of a Wireless System for Patient-Hospital Communication and Result Validation in Point of Care Testing

John McGrory et al. — Wed, 12 Jan 2011 08:59:32 PST

This paper discuses mobile phone (cell phone) and wireless applications for linking patients who manage their healthcare outside the hospital using Point of Care Testing (POCT) to hospital information systems (HIS). Certain medical conditions require patients to manage their healthcare by performing on themselves POC testing and act faithfully on the result. This raises quality control issue, as these POC samples and testing procedures are not independently overseen by professional hospital staff. In hospitals, samples taken by clinicians are validated by hi-tech computerised validation systems to ensure plausibility, before physicians rely on them. Patients in the home must often use results from these POCT to determine medication dosage or to monitor their condition. Thus, there is a need to implement a system of result validation, either locally or by the hospital validation system itself, for people testing with POCT devices.

Design of Mobile Phone Applications for Point-Of-Care test result validation.

John McGrory et al. — Wed, 12 Jan 2011 08:56:19 PST

Patients with many different conditions are required to take the management of their condition into their own hands and perform Point of Care Testing (POCT) at home. However, this raises quality control issues that would not arise in a clinical setting, since the sample acquisition and testing procedures are not overseen by professional hospital staff. Another major issue, the main focus of this research, is that results from such tests are not clinically validated to ensure that they are plausible for that patient at the time of testing. In hospital, tests taken by clinicians are validated by hi-tech computerised validation systems, before a diagnosis is made. Patients at home must often use the results of tests they take to determine medication dosage or monitor their condition, but these results do not undergo a validation procedure. Thus, there is a need to implement a system of result validation, either locally or by the hospital validation system itself, for people testing at home with POCT devices. This paper describes how mobile phone applications may be used to link patients, who manage their condition in the home, with the hospital information system (HIS) to upload and validate their results.

Patient-Centred Laboratory Validation Using Software Agents

John McGrory et al. — Wed, 12 Jan 2011 07:15:14 PST

Guidelines are self-contained documents which healthcare professionals reference to obtain knowledge about a specific condition or process. They interface with these documents and apply known facts about specific patients to gain useful supportive information to aid in developing a diagnosis or manage a condition. To automate this process a series of Standard Operating Procedures (SOP) and workflow processes are constructed using the contents of these documents in order to manage the validation flow of a patient sample. These processes decompose the guidelines into workflow plans, which are then called using condition triggers controlled by a centralised management engine. The software BDI agent offers an alternative dynamic which more closely matches the modus operandi of narrative based medical guidelines. An agent’s beliefs capture information attributes, plans capture the deliberative and action attributes, and desire captures the motivational attributes of the guideline in a self-contained autonomous software module. Agents acting on behalf of guidelines which overlap and interweave in similar domains can collaborate and coordinate in a loosely coupled fashion without the need for an all encompassing centralised plan.

A quiet success story in the laboratory: survey of 30 implementations of the ASTM 1394 standard for analyser interfaces

Brian Markey et al. — Wed, 12 Jan 2011 05:32:22 PST

In 1991 the American Society of Testing and Materials (ASTM) introduced the first version of a standard called ASTM E1394-91 for communication between centralised clinical analysers and host systems. For nearly 20 years this low key standard has been used as the basis for analyser host communications. A minor revision of the standard (ASTM1394-97) was published in 1998.

This work gives a brief summary of the development of lab messages that led to the introduction and continued use of the standard. The authors also present a review and preliminary analysis of 30 implementations of ASTM E1394. The authors investigated 30 relevant analyser interfaces in order to identify the successfuland unsuccessful features of the ASTM E1394-97 standard by assessing the compliance and non-compliance of the chosen implementations with respect to different features of the standard.

Intelligibility of Electrolarynx Speech Using a Novel Actuator

Brian Madden et al. — Mon, 10 Jan 2011 06:48:32 PST

During voiced speech, the larynx provides quasi-periodic acoustic excitation of the vocal tract. Following a laryngectomy, some people speak using an electrolarynx which replaces the excitatory function of the absent larynx. Drawbacks of conventional electrolarynx designs include the buzzing monotonic sound emitted, the need for a free hand to operate the device, and difficulty experienced by many laryngectomees in adapting to its use. Despite these shortcomings, it remains the preferred method of speech rehabilitation for a substantial minority of laryngectomees.

In most electrolarynxes, mechanical vibrations are produced by a linear electromechanical actuator, the armature of which percusses against a metal or plastic plate at a frequency within the range of glottal phonation. As part of the ongoing development of a hands-free alternative to the conventional electrolarynx, the authors have developed a novel actuator which is based on a lightweight pager motor similar to those used to produce vibration in many mobile phones.

In this paper, the intelligibility of speech produced using the novel actuator is compared to speech produced using a conventional electrolarynx. Three able-bodied speakers (two male, one female) performed a closed response test containing 48 monosyllabic words, once using a conventional electrolarynx and a second time using the novel actuator. The resulting audio recordings were randomized and replayed to four listeners who recorded each word that they heard. The results show that the speech produced using the novel actuator was substantially more intelligible to all listeners than that produced using the conventional electrolarynx.

The new actuator has properties (size, weight, shape, cost) which lends itself as a suitable candidate for possible hands-free operation. This is one of the research ideals for the group and this test methodology presented as a means of testing intelligibility. Any further actuators which exhibit desirable characteristics are also to be examined for electrolaryngeal intelligibility using this test procedure.

Software Agents Representing Medical Guidelines

John McGrory et al. — Mon, 10 Jan 2011 06:48:31 PST

Guidelines are self-contained documents which healthcare professionals reference to obtain specific disease or medical condition knowledge for a particular population cohort. They view these documents and apply known facts about their patients to access useful supportive information to aid in developing a diagnosis or manage a condition. Traditional CIG models decompose these guidelines into workflow plans, which are then called using certain motivational trigger conditions controlled by a centralised management engine.

Therefore, CIG guidelines are not self-contained documents, which specialise in a particular condition or disease, but are effectively a list of workflow plans, which are called and used when the patient information is available. The software BDI agent offers an alternative approach which more closely matches the modus operandi of narrative based medical guidelines. An agent’s beliefs capture information attributes, plans capture the deliberative and action attributes, and desire captures the motivational attributes of the guideline in a self-contained autonomous software module. This synergy between the narrative guideline and the BDI agent offers an improved solution for computerising medical guidelines when compared to the CIG approach

Communication of Medical Information Using Agents

John McGrory et al. — Mon, 10 Jan 2011 06:48:29 PST

Agents are self-contained software entities which act faithfully and autonomously on behalf of a body of knowledge. They can operate in a standalone capacity, or as part of a social group collaborating and

coordinating activities with other software agents. To access their knowledge, agents are interfaced with

using message passing communication. The principle behind medical communications is to provide a means

for exchanging information and knowledge from one computerised location to another, whilst preserving its

true meaning and understanding between the listener and sender. Agent communication is similar to medical

communications, but must provide an additional framework element to allow agents to interact at a social

and operational level. Social aspects relate to agents collaborating on shared objectives, and operational

aspects relate to coordination of tasks between the loosely coupled agents working as part of a group.

Medical communications focus on data exchanges specific to the medical domain, while agent

communication was designed for a much broader audience. Therefore, it is essential to verify if agent

communications can support standard medical data exchanges. This paper investigates current forms of

agent based communications and demonstrates they can support medical communication, yet retain their

social and interaction information exchange functionality.

Intelligibility of Electrolarynx Speech using a Novel Hands-Free Actuator

Brian Madden et al. — Mon, 10 Jan 2011 06:48:28 PST

During voiced speech, the larynx provides quasi-periodic acoustic excitation of the vocal tract. In most electrolarynxes, mechanical vibrations are produced by a linear electromechanical actuator, the armature of which percusses against a metal or plastic plate at a frequency within the range of glottal excitation. In this paper, the intelligibility of speech produced using a novel hands-free actuator is compared to speech produced using a conventional electrolarynx. Two able-bodied speakers (one male, one female) performed a closed response test containing 28 monosyllabic words, once using a conventional electrolarynx and a second time using the novel design. The resulting audio recordings were randomized and replayed to ten listeners who recorded each word that they heard. The results show that the speech produced using the hands-free actuator was substantially more intelligible to the majority of listeners than that produced using the conventional electrolarynx. The new actuator has properties (size, weight, shape, cost) which lends itself as a suitable candidate for possible hands-free operation. This is one of the research ideals for the group and this test methodology presented as a means of testing intelligibility. This paper outlines the procedure for the possible testing of intelligibility of electrolarynx designs.