Search PubMed⌕ Search

Biomedical subjects

J C Honeyman

Publications and source records attributed to J C Honeyman.

At least 19 recordsLinked to original sources
PubMed2001

Managing predefined templates and macros for a departmental speech recognition system using common software.

The authors have developed a networked database system to create, store, and manage predefined radiology report definitions. This was prompted by complete departmental conversion to a computer speech recognition system (SRS) for clinical reporting. The software complements and extends the capabilities of the SRS, and 2 systems are integrated by means of a simple text file format and import/export functions within each program. This report describes the functional requirements, design considerations, and implementation details of the structured report management software. The database and its interface are designed to allow all radiologists and division managers to define and update template structures relevant to their practice areas. Two key conceptual extensions supported by the template management system are the addition of a template type construct and allowing individual radiologists to dynamically share common organ system or modality-specific templates. In addition, the template manager software enables specifying predefined report structures that can be triggered at the time of dictation from printed lists of barcodes. Initial experience using the program in a regional, multisite, academic radiology practice has been positive.

Computer Peripherals↗
PubMed2000

Effects of a large-scale deployment of soft-copy devices for picture archiving and communication systems viewing.

A study was developed to investigate several aspects of deployment of stand-alone computers and a web-based server for displaying digital images. The costs associated with installation, upgrades, training, and maintenance of both systems were documented, as well as patterns of usage and preferences of physicians for the two types of systems. A clinical archive was created to store relevant images with a web-based front end. Users were classified according to their imaging requirements and were given access to images from either the diagnostic archive (full study sets) or the clinical archive. The range of functionality of the web-based system was significantly lower than that of the stand-alone system; however, the costs associated with the administration of the stand-alone systems were far higher than those associated with a web server. A clinical archive was created to store relevant images with a web-based front end. This study illustrates the different approaches to distribution of images to clinicians with the costs of administration of each system.

Computer Storage Devices↗
PubMed1999

Information systems integration in radiology.

Advances in information systems and technology in conjunction with outside forces requiring improved reporting are driving sweeping changes in the practice of radiology. In most academic radiology departments, there can be at least five separate information systems in daily use, a clinical picture archiving and communication system (PACS), a hospital information system (HIS), a radiology information system (RIS), a voice-recognition dictation system, and an electronic teaching/research file system. A PACS will have incomplete, incorrect, and inconsistent data if manual data entry is used. Correct routing of studies for diagnostic reporting and clinical review requires accurate information about the study type and the referring physician or service, often not easily entered manually. An HIS is a hospital-wide information system used to access patient information, reports from various services, and billing information. The RIS is typically a system specifically designed to place radiology orders, to receive interpretations, and to prepare bills for patients. Voice-recognition systems automatically transcribe the radiologist's dictation, eliminating transcription delays. Another system that is needed in a teaching hospital holds images and data for research and education. Integration of diverse systems must be performed to provide the functionality required by an electronic radiology department and the services it supports. Health Level 7 (HL7) and Digital Imaging and Communications in Medicine (DICOM) have enabled sharing of data among systems and can be used as the building blocks for truly integrated systems, but the user community and manufacturers need to specify the types of functionality needed to build clinically useful systems. Although technology development has produced the tools for interoperability for clinical and research/educational use, more work needs to be done to define the types of interaction that needs to be performed to realize the potential of these systems.

Computer Communication Networks↗
PubMed1998

Nuclear medicine data communications.

Nuclear Medicine was one of the earliest imaging modalities to adopt the use of computers for acquisition, processing, storage, and display of digital images. Originally used for processing images, computer technologies were quickly adopted for image storage, display, and transmission. Modern nuclear medicine cameras produce digital images that can be transmitted over computer networks to other cameras, storage devices, workstations, and printers. In order to achieve nuclear medicine data communication, images must be successfully acquired and transmitted to the appropriate location to be displayed or printed. Standards have been developed over the years to facilitate the creation of interfaces between vendors and equipment, notably the interfile format for nuclear medicine and the DICOM standard for medical images. Studies can be transmitted over network communication links to other sites using telecommunication protocol standards where they can be stored and/or displayed on a wide variety of devices. This ability to move images in a well-understood format to general purpose devices using standard equipment enables the use of the Internet to disseminate nuclear medicine study information over a wide area for clinical use, research, and education. A number of universities have created Internet sites with nuclear medicine teaching files and information. As technology advances, it will be feasible to transmit medical images of all kinds to virtually anyone who needs them in near real-time, without regard to the distance between locations, or the types of instrumentation and computers used. The next few years should prove to be very interesting for digital medical imaging in general and nuclear medicine in particular.

Computer Communication Networks↗
PubMed1996

A cost-analysis of computed radiography and picture archiving and communication systems in portable radiography.

A total of 40,000 portable examinations are performed each year at Shands Hospital (Gainesville, FL), a 570-bed teaching hospital. Radiographs are obtained using a screen-film combination with the films digitized for transmission to displays in four intensive care units. A cost-analysis of replacing screen-film with computed radiography (CR) integrated into a filmless picture archiving and communication system (PACS) network was performed. Equipment requirements included two CR units, three high-resolution dual monitor displays, and an archive to store 3 months of image data. The capital costs were amortized over a 5-year period. Capital and operating costs of the proposed expansion to the existing PACS network, together with anticipated cost savings, were determined. The maximum data transfer rate for portable examinations was 150 MByte per hour and approximately 400 GByte of image data are generated each year. These figures were used to determine the hardware requirements for handling the acquisition, transfer, and display of the images. Annual costs of the proposed expansion were about $220,000. Cost savings were achieved by elimination of film, including its handling by technologists/library clerks, and amounted to about $200,000 per year.

Adult↗
PubMed1996

Picture archiving and communication system bandwidth and storage requirements.

The purpose of this work was to determine the requirements for image storage and network bandwidth for a total digital department in a moderate sized academic radiology department. Data from the radiology information system was combined with image production information to produce a model of image acquisition. Destinations of images to reading rooms were studied to determine the final distributions of film. All findings were used to model the flow of data that would be expected if the images in the department were completely digital. Using today's standards, the department would produce approximately 15.7 Gbytes of data per day or 3.5 Tbytes of data per year if all acquisitions were digital. The peak acquisition rate would be 1.8 Gbytes per hour with a sustained rate greater than 1 Gbyte per hour for most of the working day. The anticipated bandwidth for the total digital department exceeded the capabilities of the existing picture archiving and communication system equipment. A distributed networked archive solution was shown to optimize access to images by radiologists and referring clinicians.

Computer Storage Devices↗
PubMed1996

Computed radiography and film digitizer inputs to an intensive care unit teleradiology system: an image quality comparison.

RATIONALE AND OBJECTIVES: We compared computed radiography (CR) with a film digitizer as an image input device for transmitting radiographs to intensive care unit (ICU) displays. METHODS: Limiting spatial resolution and low-contrast detectability performance were determined for a 600-speed screen-film combination and CR films. The same image data were transmitted to ICU displays directly from the CR or by digitizing the conventional film. RESULTS: CR resolution ranged from 2.5 to 3 line pairs per millimeter (Ip/ mm) depending on cassette size. Display station resolution for the CR image data was 1.5-1.9 lp/mm, but improved resolution could be achieved using display magnification modes. Film digitization resulted in a loss of resolution. Direct transmission of CR image data to display stations gave low-contrast detectability similar to that obtained with CR film. CONCLUSION: ICU teleradiology displays that use CR, rather than film digitizers, offer improved image quality and superior operational efficiency.

Intensive Care Units↗
PubMed1996

Medical physics.

Explore the source record for details and available documents.

Biophysics↗
PubMed1994

A technique to localize activation in the human brain with technetium-99m-HMPAO SPECT: a validation study using visual stimulation.

UNLABELLED: This study extends and validates a system for localizing brain activity changes based on fiducial markers, coregistration of SPECT and MRI structural images and atlas/MRI-assisted localization. METHODS: Ten normal subjects underwent 99mTc-HMPAO SPECT during a resting eyes-closed baseline measurement and during visual stimulation (8-Hz reversing checkerboard). SPECT scans were registered with MRI scans obtained from each individual using a fiducial-based system that minimized z-axis and rotational errors, and registration was further refined along the x- and y-axes by superimposing corresponding axial SPECT and MRI slices. Regions of interest (ROIs) were located on MRI slices with the aid of an atlas. Corresponding loci on SPECT slices were chosen and incrementally adjusted such that the center of a ROI was located precisely at the maximum of activity in the visual cortex or the cortical gray matter ribbon. RESULTS: Activity in the calcarine cortex increased by 44.39% during visual stimulation (p < 0.001). Adjustment of ROI location in accordance with local activity maxima yielded superior results to a method relying strictly on atlas/MRI localization. Premotor cortex activity declined by 16.91% on the right (p < 0.01) and 13.85% on the left (p > 0.05), whereas no changes occurred in the somatosensory cortex. CONCLUSION: Changes in visual cortical activity were most comparable to previous functional MRI studies but also congruent with PET and SPECT findings. Using the locus of peak activity to aid in defining cortical ROIs improves the signal-to-noise ratio by reducing noise related to inevitable minor registration errors.

Adolescent↗
PubMed1993

Angelman and Prader-Willi syndrome: a magnetic resonance imaging study of differences in cerebral structure.

Recent improvements in magnetic resonance imaging techniques now allow the developing brain to be visualized in sufficient detail to perform "in vivo neuropathology." In this study we compared the cortical morphology in six children with Angelman and four with Prader-Willi syndrome. These two syndromes are of special interest because, although they are both caused by deletions in the same region of chromosome 15, Angelman children are far more severely affected, and do not speak. We measured the length of the banks of the Sylvian fissure in a gapless series of thin sagittal images. Angelman children had a significantly larger proportion (75%) of anomalous fissures than the Prader-Willi children (12%). Anomalous cortical growth could result from mistimed expression and recognition of macromolecules involved in axonal guidance, target recognition, and pruning. We hypothesize that misrouting of long projection axons may be related to the Sylvian fissure anomalies and the language disorder in Angelman syndrome.

Angelman Syndrome↗
PubMed1993

Anomalous cerebral structure in dyslexia revealed with magnetic resonance imaging.

OBJECTIVE: To develop quantitative methods for identifying cerebral anomalies on magnetic resonance images of subjects with language disorders and other learning disabilities. DESIGN: Partially blinded comparison of subjects with dyslexia, unaffected relatives, and a control group balanced for age and socioeconomic status. Criterion standard: clinical diagnosis of dyslexia by physician or learning disabilities specialist on the basis of clinical assessment and family history. SETTINGS: Hospital pediatric neurology clinic and private reading clinic. PATIENTS AND OTHER PARTICIPANTS VOLUNTEERS: individuals with dyslexia (seven male and two female, aged 15 to 65 years) from professional families; unaffected first- and second-degree relatives (four male and six female, aged 6 to 63 years) available in the geographical area; and controls (five male and seven female, aged 14 to 52 years). INTERVENTIONS: Gradient echo three-dimensional scan in Seimens 1-Tesla Magnetom; 128 1.25-mm consecutive sagittal images. MAIN OUTCOME MEASURES: (1) Average length of the temporal (T) and parietal (P) banks of the planum temporale; (2) interhemispheric coefficients of asymmetry for T and P banks: Left-Right interhemispheric coefficients of asymmetry = (L-R)/[(L+R)/2]; (3) intrahemispheric coefficients of asymmetry = (T-P)/[(T+P)/2]; and (4) qualitative assessment of gyral variants in the parietotemporal operculum. RESULTS: All groups had left-sided asymmetry for the temporal bank and right-sided asymmetry for the parietal bank. The group with dyslexia had exaggerated asymmetries, owing to a significant shift of right planar tissue from the temporal to parietal bank. They also had a higher incidence of cerebral anomalies bilaterally (subjects with dyslexia, six of nine; relatives, two of 10; and controls, zero of 12). CONCLUSIONS: Quantitative assessment of high-resolution magnetic resonance images can reveal functionally relevant variations and anomalies in cerebral structure. Further refinement of these measurement techniques should improve the diagnosis, classification, and treatment of language disorders and other learning disabilities.

Adolescent↗
PubMed1993

Historical perspective on computer development and glossary of terms.

This article contains a concise history of the development of mechanical and electronic computers, descriptions of the milestones in software development, discussion of the introduction and adoption of computers in radiology, and a glossary of computer terms used frequently in radiology. One of the earliest devices designed to mechanize calculations was the calculating clock, built in 1623. The first programmable electronic computer, the ENIAC (electronic numerical integration and computer), was completed in 1945 at the University of Pennsylvania. Software has developed from early machine language through fourth-generation languages and graphic user interfaces used today. The computer was introduced to radiology initially in the 1960s in nuclear medicine and is now incorporated in many digital imaging modalities throughout radiology. The development of picture archiving and communication systems has resulted in the implementation of several totally digital departments of radiology.

Computers↗
PubMed1992

Evaluation of requirements and planning for picture archiving and communication systems.

Successful implementation of a picture archiving and communication system (PACS) requires extensive planning and the input of the users in the planning and evaluation stages. System design is conducted in nine stages: systems analysis, stages 1-4; system design, stages 5 and 6; and system implementation, stages 7-9. Users of the PACS are actively involved in systems analysis. At stage 1, problems are identified, project scope is defined, and whether the problems can be successfully addressed with a PACS is determined. If the project is feasible, current systems are studied at stage 2. Data are collected on the volume of image data to be transmitted, stored, retrieved, and displayed; distribution of imaging through the day; radiologists' reading patterns and volumes; job functions of technologists; characteristics of images to be included; types of equipment to be interfaced; physical placement of cables, connections, and equipment; and operational restrictions. All these data and more are used in stage 3 to specify requirements of the PACS. Rigorous specifications are needed to ensure that the final system performs at the desired level. At stage 4, users evaluate alternative solutions to problems. Although consultants and equipment manufacturers do much of the design, implementation, and installation, users must understand project scope and limitations of the technology and must ultimately be responsible for planning a system that meets their needs.

Cluster Analysis↗
PubMed1992

Image archival technologies.

A typical radiology department can create many gigabytes of image data per day and as much as 1 terabyte of data per year. Archiving and accessing this much data are substantial problems. One solution is data compression, which decreases data storage requirements and increases the rate of data transfer; however, standards are not yet available. Other solutions involve improvements in archival media. Jukebox subsystems allow automated access to multiple units. Digital magnetic tape, the standard medium, can store large amounts of information and enables easy updates or replacements; more practical technologies have been introduced in recent years. Digital videotape allows storage of digital video data and features a high rate of data transfer. Optical disks, now the preferred permanent archival medium, have a large storage capacity and provide excellent long-term stability. Optical tape is also being investigated as a solution to the archiving dilemma. Which technology to choose depends on many factors, including needs of the institution and the cost, stability, transfer time, and storage capacity of the system.

Computer Storage Devices↗
PubMed1992

PACS mini refresher course. Wide area network strategies for teleradiology systems.

Teleradiology systems require the use of wide area networks (WANs). Design and implementation of a WAN depend on the number of images to be transmitted, desired digital image throughput (based on signaling rate), and cost of the communications link. Image transmission load must be estimated before the communications link can be selected. Communications links used in WANs include T-1 carrier point-to-point service, digital service (DS)-1 dial-up service, DS-3 point-to-point service, DS-0 dial-up service, digital microwave, fiberoptic local loop carriers, and metropolitan area networks (MANs). Depending on the distance between sites, T-1 service may be less costly than DS-1 service; however, for distances more than 200 miles, DS-1 service can be less expensive and more flexible. Both of these services and DS-0 service have lower signaling rates than DS-3 service, which is the fastest and most expensive link. Microwave and fiberoptic links are less expensive but have distance limitations of 14 and 30 miles, respectively. MANs are still being developed but hold the promise of higher signaling rates at lower costs.

Computer Communication Networks↗
PubMed1992

Performance characteristics and image fidelity of gray-scale monitors.

Gray-scale monitors are an essential element of electronic radiology, and their ability to provide images that are perceived to be identical to those available on conventional or laser-printed film is crucial to success of electronic radiology. Image fidelity is measured in physical characteristics (luminance, dynamic range, distortion, resolution, and noise) and with psychophysical techniques, including receiver operator characteristics analysis with clinical images and testing with contrast-detail patterns to determine threshold contrast. Currently, laser-printed images facilitate greater information transfer than does a gray-scale monitor because of their higher absolute luminance (500 ft-L vs 60 ft-L), greater perceived dynamic range, and better spatial resolution. In the near future, the developments of gray-scale monitors with 150-200 ft-L luminance, a display standard based on just noticeable differences, and algorithms to improve similarities between gray-scale display images and laser-printed images will help increase the acceptability of monitors as a means to make primary diagnoses.

Computer Peripherals↗