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PubMed2005

Direct comparison of a tablet computer and a personal digital assistant for point-of-care documentation in eye care.

New mobile computing devices including personal digital assistants (PDAs) and tablet computers have emerged to facilitate data collection at the point of care. Unfortunately, little research has been reported regarding which device is optimal for a given care setting. In this study we created and compared functionally identical applications on a Palm operating system-based PDA and a Windows-based tablet computer for point-of-care documentation of clinical observations by eye care professionals when caring for patients with diabetes. Eye-care professionals compared the devices through focus group sessions and through validated usability surveys. We found that the application on the tablet computer was preferred over the PDA for documenting the complex data related to eye care. Our findings suggest that the selection of a mobile computing platform depends on the amount and complexity of the data to be entered; the tablet computer functions better for high volume, complex data entry, and the PDA, for low volume, simple data entry.

Attitude of Health Personnel↗
PubMed1991

Developing trends in clinical computing.

With the emergence of personal computers and graphical interfaces during the 1980s, advanced computational power has at last become accessible and affordable for practising clinicians in both inpatient and outpatient settings. Many observers have accordingly noted the relatively low level of direct computer use by physicians in their practices. This paper summarises developing trends in clinical computing, emphasising the role of local and wide-access networks, the revolutionary potential of optical storage techniques, and the notion of integrated workstations that will bring a critical mass of diverse functions to the physician. An important lesson of this review is the current availability of most of the technologies needed for high-quality and acceptable clinical computing tools. The barriers to successful implementation tend to be logistical, financial, and political. Despite these obstacles, new technologies, coupled with educational efforts, should allow the computer to emerge as a crucial aid to clinicians in the decade ahead.

Attitude to Computers↗
PubMed1990

Applications of computer technology in dentistry.

Technological advances in industrial manufacturing have contributed to improvement in productivity and quality of dental care. However, computer technology has also been exploited but not to the same extent as other forms of technology. This paper examines computer applications that have been utilised by various groups of dental professionals in the provision of dental care and in dental education. The benefits derived from existing applications and future possibilities are seen in the following fields. In practice management, besides the usual collecting, sorting and searching of data, productivity and efficiency are greatly increased through computer appointments, recall and practice analysis programmes. In patient education, the use of computer graphics has enabled simulation of cosmetic changes to be presented to the patient with before and after possibilities. Dental education and communications have moved forward with the introduction of Computer Assisted Instruction programmes, and bibliographic databases including electronic transmission of Continuing Dental Education which are now easily available. In the field of Diagnostics and Treatment planning, the advent of CAD-CAM has made possible the use of cutting devices which mills a 3-dimensional model of the designed restoration from solid blocks of gold. Computer applications has also been used in forensic dentistry where identification systems describe tooth conditions and other oral characteristics besides automated screening and matching of antemortem databases.

Computer-Assisted Instruction↗
PubMed1986

Computer-aided simulation, analysis, and design in orthopedic surgery.

Three-dimensional computer reconstructions of bony anatomy based on computed tomographic images and radiographs may be used to analyze, simulate, and design certain orthopedic procedures. In osteotomy surgery, the computer-reconstructed models may be used to measure critical angles, surface area, and congruity of the joint surfaces. Computer reconstructions may be used in total joint replacement surgery to simulate the effect of surgical reamers and rasps, to select the geometrically optimum standard implant, or to design a custom implant. In allograft reconstructive surgery, computer reconstructions may be used to measure bony defects and to identify the appropriate allografts for the reconstruction. Plastic models may be sterilized and used as templates to sculpt the allografts immediately preoperatively. In all three applications in orthopedic surgery, three-dimensional, computer-aided reconstructions have the potential to improve results and reduce morbidity.

Bone Transplantation↗
PubMed1995

A desk top computer program for visualized statistical analysis of lesional images in intracerebral hemorrhage.

Statistically identified information on the relationships between the sites of lesions in intracerebral hemorrhage (ICH), risk factors such as a smoking or drinking habit, anamnesis, and biochemical data through blood tests will extend assistance to neuromedical clinicians on their daily clinical duties. It will provide them with a useful guide to determine the method of treatment. Also, it will be a basic research material for their clinical studies on diagnosis, progress, or prognosis in ICH. In order to obtain such statistics with the help of the computer, we need to have a computationally effective image database system. As is generally known, medical image data especially requires a great amount of storage; high-speed processing techniques are therefore also needed to deal with such data effectively. In addition, it is desired that we have outputs from the analysis edited with well-visualized effect, using 3D computer graphics, etc. These are why most existing image processing systems have been designed to work on comparatively large-scale computers. So far as we know, it is hard to find a practical and inexpensive personal computer-based application system for visualized statistical analysis of lesional images in ICH. We have developed a desk top computer-based program for statistical analysis of lesional image data of ICH. With this system, we can organize a medical image database that consists of the personal data of patients with ICH (sex, age, occupation, diagnosis, symptoms, part of physical disorder, etc.), risk factors, anamnesis (cerebral apoplexy, hypertension, hypotension, corpulence, diabetes, hyperlipidemia, atrial fibrillation, valvular endocarditis, etc.), biochemical data of blood, and lesional image data from CT or MRI. This system consists of the following components: 1) database management, 2) information retrieval (IR), 3) lesional image processing, 4) statistical analysis, and 5) prognostic prediction. The images are drawn manually on prescribed data sheets by tracing CT or MRI films and are read through the image scanner; then the compressed data of the digitized images is recorded in the database. Each recorded image data consists of the following two components: the frame image that corresponds to the contour of tissues of interest on the corresponding sliced section, and the actual image that corresponds to the lesion itself. In our system, these two images are separately stored and managed so that we can effectively perform subsequent image analysis. Other variables in the database (risk factors, anamnesis, etc.) are mainly used as search keys for making the aggregate of image data by the IR subsystem. In any aggregate, its elements, namely image data, have common medical background descriptions with the search keys. These aggregates can be used as input for the lesional image processing subsystem. With this subsystem, we can obtain the accumulated distribution of frequencies within a specified range of any sliced section, display planar color maps and profiles associated with the distribution, reconstruct it in 3D form, perform transformations of 3D images (zooming, enhancement, rotation, etc.), and test the significant difference of frequencies between any two different sites. We have been making practical use of this system to find the neurological relationship between the symptom (dysarthria, and paralysis of upper/lower limbs) and the site of lesion with cerebral infarction in pons. This study is quite important since the distributions of pyramidal tract related to the above symptom in pons are not well-known compared to those in cerebral cortex, internal capsule, or cerebral peduncle. With our system, we have obtained several findings expected to be helpful for this study. However, since this study is still in the initial phases, we will only present the outcome as a working example of our system. Our system was originally developed for analyzing lesional images with ICH. However, it could

Cerebral Hemorrhage↗
PubMed1995

A computer-controlled conformal radiotherapy system. III: Graphical simulation and monitoring of treatment delivery.

PURPOSE: Safe and efficient delivery of radiotherapy using computer-controlled machines requires new procedures to design and verify the actual delivery of these treatments. Graphical simulation and monitoring techniques for treatment delivery have been developed for this purpose. METHODS AND MATERIALS: A graphics-based simulator of the treatment machine and a set of procedures for creating and manipulating treatment delivery scripts are used to simulate machine motions, detect collisions, and monitor machine positions during treatment. The treatment delivery simulator is composed of four components: a three-dimensional dynamic model of the treatment machine; a motion simulation and collision detection algorithm, user-interface widgets that mimic the treatment machine's control and readout devices; and an icon-based interface for creating and manipulating treatment delivery scripts. These components are used in a stand-alone fashion for interactive treatment delivery planning and integrated with a machine control system for treatment implementation and monitoring. RESULTS: A graphics-based treatment delivery simulator and a set of procedures for planning and monitoring computer-controlled treatment delivery have been developed and implemented as part of a comprehensive computer-controlled conformal radiotherapy system. To date, these techniques have been used to design and help monitor computer-controlled treatments on a radiotherapy machine for more than 200 patients. Examples using these techniques for treatment delivery planning and on-line monitoring of machine motions during therapy are described. CONCLUSION: A system that provides interactive graphics-based tools for defining the sequence of machine motions, simulating treatment delivery including collision detection, and presenting the therapists with continual visual feedback from the treatment machine has been successfully implemented for routine clinical use as part of an overall system for computer-controlled conformal radiotherapy treatment, and is considered a necessary part of the routine treatment methodology.

Computer Graphics↗
PubMed1997

World Wide Web interface for advanced SPECT reconstruction algorithms implemented on a remote massively parallel computer.

Data from Single Photon Emission Computed Tomography (SPECT) studies are blurred by inevitable physical phenomena occurring during data acquisition. These errors may be compensated by means of reconstruction algorithms which take into account accurate physical models of the data acquisition procedure. Unfortunately, this approach involves high memory requirements as well as a high computational burden which cannot be afforded by the computer systems of SPECT acquisition devices. In this work the possibility of accessing High Performance Computing and Networking (HPCN) resources through a World Wide Web interface for the advanced reconstruction of SPECT data in a clinical environment was investigated. An iterative algorithm with an accurate model of the variable system response was ported on the Multiple Instruction Multiple Data (MIMD) parallel architecture of a Cray T3D massively parallel computer. The system was accessible even from low cost PC-based workstations through standard TCP/IP networking. A speedup factor of 148 was predicted by the benchmarks run on the Cray T3D. A complete brain study of 30 (64 x 64) slices was reconstructed from a set of 90 (64 x 64) projections with ten iterations of the conjugate gradients algorithm in 9 s which corresponds to an actual speed-up factor of 135. The technique was extended to a more accurate 3D modeling of the system response for a true 3D reconstruction of SPECT data; the reconstruction time of the same data set with this more accurate model was 5 min. This work demonstrates the possibility of exploiting remote HPCN resources from hospital sites by means of low cost workstations using standard communication protocols and an user-friendly WWW interface without particular problems for routine use.

Algorithms↗
PubMed2000

Penalized weighted least-squares image reconstruction for dual energy X-ray transmission tomography.

We present a dual-energy (DE) transmission computed tomography (CT) reconstruction method. It is statistically motivated and features nonnegativity constraints in the density domain. A penalized weighted least squares (PWLS) objective function has been chosen to handle the non-Poisson noise added by amorphous silicon (aSi:H) detectors. A Gauss-Seidel algorithm has been used to minimize the objective function. The behavior of the method in terms of bias/standard deviation tradeoff has been compared to that of a DE method that is based on filtered back projection (FBP). The advantages of the DE PWLS method are largest for high noise and/or low flux cases. Qualitative results suggest this as well. Also, the reconstructed images of an object with opaque regions are presented. Possible applications of the method are: attenuation correction for positron emission tomography (PET) images, various quantitative computed tomography (QCT) methods such as bone mineral densitometry (BMD), and the removal of metal streak artifacts.

Algorithms↗
PubMed2002

Nasal airflow diagnosis--comparison of experimental studies and computer simulations.

The lack of suited diagnostic tools providing insight into patient specific flow characteristics of the nasal airflow is one of the main problems in functional diagnosis. Diagnostic methods currently used do not provide the necessary information for flow analysis. But the flow distribution is essential for a physiological respiration, in particular for cleaning, moistening and tempering of the inhaled air as well as for the olfactory function of the nose. To overcome this current situation a cooperation project of the ENT surgeons and computer graphic engineers was established to develop the computer assisted planning system STAN (Simulation Tool for Airflow in the human Nose) combining Computer Fluid Dynamics (CFD) with advanced Computer Graphic Technology. The idea of the STAN system is to perform patient specific airflow simulations in the patient's nasal cavities. Therefore a geometrical model of the nasal airways is derived from the patient's tomography scans. A discretization of the surrounded flow volume is made by a computational grid. To establish the flow simulation Finite Element Methods are performed on the grid. A tailored visualization is offered to the surgeon that overlaps the flow pattern to the patient's tomography data shown in the coronal, sagittal and transversal plane. The surgeon can not only analyze the patient's current respiratory situation he has also the possibility to describe the planned surgical intervention. The goal is to simulate the flow distribution that can be expected after the surgical intervention and to offer a possibility to validate various surgical strategies. To verify the simulation results experimental investigations and measurements are made in nasal models. Silicon Models of patient's nose channels are made to analyze flow characteristics. The CT or MR scans of the same patients are used as input data for the simulation. The experimental outcome is compared to the simulation results to validate this diagnostic approach.

Computer Simulation↗
PubMed2001

CMEIAS: A Computer-Aided System for the Image Analysis of Bacterial Morphotypes in Microbial Communities.

A major challenge in microbial ecology is to develop reliable and facile methods of computer-assisted microscopy that can analyze digital images of complex microbial communities at single cell resolution, and compute useful quantitative characteristics of their organization and structure without cultivation. Here we describe a computer-aided interactive system to analyze the high degree of morphological diversity in growing microbial communities revealed by phase-contrast microscopy. The system, called "CMEIAS" (Center for Microbial Ecology Image Analysis System) consists of several custom plug-ins for UTHSCSA ImageTool, a free downloadable image analysis program operating on a personal computer in a Windows NT environment. CMEIAS uses various measurement features and two object classifiers to extract size and shape measurements of segmented, digital images of microorganisms and classify them into their appropriate morphotype. The first object classifier uses a single measurement feature to analyze relatively simple communities containing only a few morphotypes (e.g., regular rods, cocci, filaments). A second new hierarchical tree classifier uses an optimized subset of multiple measurement features to analyze significantly more complex communities containing greater morphological diversity than ever before possible. This CMEIAS shape classifier automatically categorizes each cell into one of 11 predominant bacterial morphotypes, including cocci, spirals, curved rods, U-shaped rods, regular straight rods, unbranched filaments, ellipsoids, clubs, rods with extended prostheca, rudimentary branched rods, and branched filaments. The training and testing images for development and evaluation of the CMEIAS classifier were obtained from 1,937 phase-contrast grayscale digital images of various diverse communities. The CMEIAS shape classifier had an accuracy of 96.0% on a training set of 1,471 cells and 97.0% on a test set of 4,270 cells representing all 11 bacterial morphotype classes, indicating that accurate classification of rich morphological diversity in microbial communities is now possible. An interactive edit feature was added to address the main sources of error in automatic shape classification, enabling the operator to inspect the assigned morphotype of each bacterium based on visual recognition of its distinctive pseudocolor, reassign it to another morphotype class if necessary, and add up to five other morphotypes to the classification scheme. The shape classifier reports on the number and types of different morphotypes present and the abundance among each of them, thus providing the data needed to compute the morphological diversity within the microbial community. An example of how CMEIAS can augment the analysis of microbial community structure is illustrated by studies of morphological diversity as an indicator of dynamic ecological succession following a nutrient shift-up perturbation in two continuously fed, anaerobic bioreactors with morphologically distinct start communities. Various steps to minimize the limitations of computer-assisted microscopy to classify bacterial morphotypes using CMEIAS are described. In summary, CMEIAS is an accurate, robust, flexible semiautomatic computing tool that can significantly enhance the ability to quantitate bacterial morphotype diversity and should serve as a useful adjunct to the analysis of microbial community structure. This first version of CMEIAS will be released as free, downloadable plug-ins so it can provide wide application in studies of microbial ecology.

Journal Article↗
PubMed2001

The case for responsibility of the IT industry to promote equality for women in computing.

This paper investigates the relationship between the role that information technology (IT) has played in the development of women's employment, the possibility of women having a significant influence on the technology's development, and the way that the IT industry perceives women as computer scientists, users and consumers. The industry's perception of women and men is investigated through the portrayal of them in computing advertisements. While women are increasingly updating their technological skills and know-how, and through this process are entering some positions in the workplace traditionally occupied by men, these achievements are not mirrored in their social and occupational status. The computer industry and higher education have worryingly low numbers of women, while the possibility of women influencing the development of computer technology is just emerging in feminist research. This paper argues that, though the IT industry, through their self-regulatory codes, subscribes to equal treatment of sexes, races and persons with disabilities, the industry nevertheless paints a stereotyped picture of inequality when portraying men and women in computer advertisements. As long as such a perception of women prevails within the industry, it will stand as a barrier to women having equal access to computer technology. If advertisements influence the way society perceives major social constructs and issues, then the computing industry has a social responsibility to portray men and women in an equal and non-stereotypical fashion.

Advertising↗
PubMed1995

Computer workstation adjustment: a novel process and large sample study.

The use of computers in the US workforce is expected to grow throughout the 1990s. Prolonged computer use, repetitive keying, awkward postures and psychosocial issues have been associated with injuries described as cumulative trauma disorders (CTDs). The incidence and reporting of occupationally induced CTDs has increased dramatically since 1980. Proper adjustment of individual computer workstations requires time and technical knowledge. An automated process for computer workstation adjustment was developed using linked-segment anthropometry. Over 3300 employees in a large industrial complex voluntarily participated in this programme by completing a computer workstation questionnaire. Significant relationships were demonstrated comparing both hours and years of computer use with symptoms. A followup questionnaire was completed by 531 programme participants. Ninety percent indicated an improved understanding of proper computer adjustment. Eighty percent of those making recommended adjustments indicated benefits in reduced symptoms and greater work efficiency.

Journal Article↗
PubMed1969

An introduction to hybrid computers and their application to optimization problems.

The author, who is Secretary of the Analog Section of the British Computer Society, describes the way in which some of the logic components of a parallel logic analog computer function, and goes on to discuss the use of such a computer in optimization problems, as for instance in finding the best estimates of the parameters on compartmentation analysis of isotopic tracer experiments. The increased power which is gained when an analog computer is coupled to (hybridized with) a general purpose digital computer is then discussed, as shown for example in the increased speed of random-search optimization techniques when an analog computer is used to integrate the differential equations, or the improvement in steepest ascent methods when the parallel logic can be used to keep the hill-climb path continuously on the line of steepest ascent. Finally, the use of a hybrid computer in solving partial differential equations is briefly outlined.

Journal Article↗
PubMed1992

A comparison of two computer-administered versions of the NIMH Diagnostic Interview Schedule.

This study compared three versions of the NIMH Diagnostic Interview Schedule (DIS): "traditional" interviewer-administered DIS; computer-administered DIS (subject interacting alone with computer); computer-prompted DIS (interviewer using computer program as a guide). Kappas for 20 diagnoses ranged from .15 to .94, and averages for the three method pairs ranged from .57 to .64, which are comparable to other DIS reliability studies. Agreement between pairs of methods were comparable. Subjects' attitudes toward the computer interview were positive. While they felt they could better describe their feelings and ideas to a human, they found the computer contact less embarrassing. Overall, subjects had no preference for one method over another. Measures of social desirability and deviant response biases were correlated with diagnostic results. Reading ability did not affect subject's ability to respond to the DIS, although subjects with lower reading levels preferred the computer interview more.

Adult↗
PubMed1994

Interobserver agreement using computed radiography in the adult intensive care unit.

RATIONALE AND OBJECTIVES: We determined whether computed radiographs in an adult intensive care unit produce greater agreement between readers in descriptions of radiologic findings and interval changes. METHODS: Fifty-six conventional radiographs and 56 computed radiographs were obtained on 28 patients. Computed and conventional radiographs were imaged simultaneously in a single exposure with the use of a sandwich cassette. The two sets of films per patient were taken less than 1 week apart. RESULTS: Four readers evaluated the chest films and judged interval changes with the use of standardized confidence scales. Overall exposure and film quality also were evaluated. Computed radiographs were rated better in overall quality. Tubes and lines were detected with comparable accuracy. Interobserver agreement in the evaluation of radiologic descriptors was generally greater with computed radiographs (intraclass correlation). No differences were noted in interobserver agreement in the judgment of interval changes. CONCLUSIONS: The diagnostic usefulness of computed radiography is comparable to conventional films in the intensive care unit. The higher interobserver agreement rate for radiologic descriptors with computed radiography is an added advantage of the system.

Adult↗
PubMed2006

Efficient correlation-corrected vibrational self-consistent field computation of OH-stretch frequencies using a low-scaling algorithm.

The authors present a new computational scheme to perform accurate and fast direct correlation-corrected vibrational self-consistent field (CC-VSCF) computations for a selected number of vibrational modes, which is aimed at predicting a few vibrations in large molecular systems. The method is based on a systematic selection of vibrational mode-mode coupling terms, leading to the direct ab initio construction of a sparse potential energy surface. The computational scaling of the CC-VSCF computation on the generated surface is then further reduced by using a screening procedure for the correlation-correction contributions. The proposed method is applied to the computation of the OH-stretch frequency of five aliphatic alcohols. The authors investigate the influence of different pseudopotential and all-electron basis sets on the quality of the correlated potential energy surfaces computed and on the OH-stretch frequencies calculated for each surface. With the help of these test systems, the authors show that their method offers a computational scaling that is two orders of magnitude lower than a standard CC-VSCF method and that it is of equal accuracy.

Journal Article↗
PubMed2001

Dynamic 3D computer-assisted reconstruction of a metallic retrobulbar foreign body for diagnostic and surgical purposes. [Case report of orbital injury with ethmoid bone involvement].

The main goal of our dynamic 3D computer-assisted reconstruction of a metallic retrobulbar foreign body following orbital injury with ethmoid bone involvement was to use 3D-information obtained from standard computed tomography (CT) data to explore and evaluate the nasal cavity, ethmoidal sinuses, retrobulbar region, and the foreign body itself by simulated dynamic computed visualization of the human head. A foreign body, 10 x 30 mm in size, partially protruded into the posterior ethmoidal cells and partially into the orbit, causing dislocation and compression of the medial rectus muscle and inferior rectus muscle. The other muscles and the optic nerve were intact. Various steps were taken to further the ultimate diagnosis and surgery. Thin CT sections of the nasal cavity, orbit and paranasal sinuses were made on a conventional CT device at a regional medical center, CT scans were transmitted via a computer network to different locations, and special views very similar to those seen on standard endoscopy were created. Special software for 3D modeling, specially designed and modified for 3D C-FESS purposes, was used, as well as a 3D-digitizer connected to the computer and multimedia navigation through the computer during 3D C-FESS. Our approach achieves the visualization of very delicate anatomical structures within the orbit in unconventional (non-standard) sections and angles of viewing, which cannot be obtained by standard endoscopy or 2D CT scanning. Finally, virtual endoscopy (VE) or a 'computed journey' through the anatomical spaces of the paranasal sinuses and orbit substantially improves the 3D C-FESS procedure by simulating the surgical procedure prior to real surgery.

Journal Article↗
PubMedDate not supplied

Parallel computing in interval mapping of quantitative trait loci.

Linear regression analysis is considered the least computationally demanding method for mapping quantitative trait loci (QTL). However, simultaneous search for multiple QTL, the use of permutations to obtain empirical significance thresholds, and larger experimental studies significantly increase the computational demand. This report describes an easily implemented parallel algorithm, which significantly reduces the computing time in both QTL mapping and permutation testing. In the example provided, the analysis time was decreased to less than 15% of a single processor system by the use of 18 processors. We indicate how the efficiency of the analysis could be improved by distributing the computations more evenly to the processors and how other ways of distributing the data facilitate the use of more processors. The use of parallel computing in QTL mapping makes it possible to routinely use permutations to obtain empirical significance thresholds for multiple traits and multiple QTL models. It could also be of use to improve the computational efficiency of the more computationally demanding QTL analysis methods.

Algorithms↗