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  1. Article ; Online: Evaluation of an automatic needle-loading system.

    Morrier, Janelle / Varfalvy, Nicolas / Chrétien, Mario / Beaulieu, Luc

    Journal of applied clinical medical physics

    2004  Volume 5, Issue 2, Page(s) 82–90

    Abstract: ... RP) performance of a new automatic needle-loading system for permanent prostate implants ... that the Isoloader is a safe, fast, and effective needle-loading system. ... verification and needle loading. The reproducibility of the detector was tested and its accuracy was determined ...

    Abstract The purpose of this paper is to evaluate the dosimetric capabilities and the radiation protection (RP) performance of a new automatic needle-loading system for permanent prostate implants, the Isoloader (Mentor Corp.). The unit has been used in more than 100 clinical cases at our institution. The Isoloader is a computerized workstation that allows automated seed testing by a solid-state CdZnTe radiation detector and loading in surgical needles. The seeds are received in a shielded and ready-to-use cartridge. Radiation protection measurements were done on a cartridge filled with 67 (125)I seeds and during dosimetric seed verification and needle loading. The reproducibility of the detector was tested and its accuracy was determined by comparison to specified activities of six calibration seeds and to their measurements in a calibrated well-chamber (WC). Finally, the times required to complete dosimetric verification and needle loading were evaluated. The cartridge was found to be adequately shielded, since no significant amount of radiation was detected around it. Radiation during seed assay was found to be worst at the cartridge's bottom, where it has a value of 15.2 microSv/h (1.4 microSv/h at 10 cm). For the needle-loading task, measurements were performed with a typical needle (three seeds) at the shielded needle holder surface yielding 307.2 microSv/h (8.3 microSv/h at 20 cm). Seed dosimetric verification takes an average of 15 s/seed, while it takes a mean time of 50 s/needle to complete the loading task. Measurements of the six seed activities were within 0.65% of the ordered activities and 1.9% higher on average than those from the WC (min = 0.7%; max = 3.5%). The reproducibility of the measurements of the CdZnTe detector was excellent, with an average of 0.01% of deviation from a reference measurement (N = 120; = 1.9%). We therefore conclude that the Isoloader is a safe, fast, and effective needle-loading system.
    MeSH term(s) Brachytherapy/instrumentation ; Equipment Design ; Equipment Failure Analysis ; Injections/instrumentation ; Injections/methods ; Iodine Radioisotopes/analysis ; Iodine Radioisotopes/therapeutic use ; Needles ; Radiation Dosage ; Radiation Monitoring ; Radiation Protection/instrumentation ; Radiation Protection/methods ; Risk Assessment/methods ; Risk Factors ; Robotics/instrumentation ; Robotics/methods ; Specimen Handling/instrumentation ; Specimen Handling/methods
    Chemical Substances Iodine Radioisotopes
    Language English
    Publishing date 2004-04-01
    Publishing country United States
    Document type Evaluation Studies ; Journal Article
    ZDB-ID 2010347-5
    ISSN 1526-9914 ; 1526-9914
    ISSN (online) 1526-9914
    ISSN 1526-9914
    DOI 10.1120/jacmp.v5i2.1971
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  2. Article ; Audio / Video: Performance evaluation of an automated detection and control system for volunteer potatoes in sugar beet fields

    Nieuwenhuizen, A.T / Hofstee, J.W / Henten, E.J. van

    Biosystems engineering. 2010 Sept., v. 107, issue 1

    2010  

    Abstract: ... with a micro-sprayer with five needles and a working width of 0.2 m. The accuracy of the system was ±14 mm ... Incomplete control of volunteer potato plants causes a high environmental load through increased ...

    Abstract Incomplete control of volunteer potato plants causes a high environmental load through increased crop protection chemical usage in potato cropping. A joint effort of industry, policy makers and science initiated a four year scientific project on detection and control of volunteer potato plants. A proof-of-principle machine for automated detection and control of volunteer potato plants in sugar beet fields has been tested in experimental fields. Machine vision-based detection at 100 mm2 precision is combined with a micro-sprayer with five needles and a working width of 0.2 m. The accuracy of the system was ±14 mm in longitudinal direction and ±7.5 mm in transverse direction. The main error source was the variability in micro-sprayer droplet velocity that caused longitudinal errors. However, 77% of volunteer plants with a size larger than 1200 mm2 were successfully controlled at machine speeds up to 0.8 m s−1. Within the crop row, glyphosate was applied on weed potato plants and this resulted in the unwanted death of up to 1.0% of sugar beet plants.
    Keywords automatic detection ; potatoes ; sugar beet ; weed control ; crop-weed competition ; field experimentation ; image analysis ; precision agriculture ; Netherlands
    Language English
    Dates of publication 2010-09
    Size p. 46-53.
    Document type Article ; Audio / Video
    ZDB-ID 2075942-3
    ISSN 1537-5110
    ISSN 1537-5110
    DOI 10.1016/j.biosystemseng.2010.06.011
    Database NAL-Catalogue (AGRICOLA)

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  3. Book: A comparative report of four small field digital imaging systems for mammography

    Great Britain. / Medical Devices Agency.

    (MDA evaluation report ; MDA/99/15)

    1999  

    Abstract: ... evaluated are provided with automatic control of exposure through the detector system in addition to manual ... workstations provide a range of image processing and handling facilities plus the operating system for image ... given in the operator's manual. Typical exposure parameters showed considerable variation from system to system and ...

    Author's details King's Centre for the Assessment of Radiological Equipment (KCARE)
    Series title MDA evaluation report ; MDA/99/15
    Abstract Currently, four suppliers in the United Kingdom offer small field digital imaging systems for use with mammography X-ray units. These are designed primarily for stereotactic localisations but may also be used for spot imaging and magnified views. They may also have applications in specimen radiography. All of the systems offered employ detectors based on charge coupled device (CCD) camera technology. The associated workstations provide a range of image processing and handling facilities plus the operating system for image acquisition and patient information management. The user evaluation confirmed that the major use of small field imaging systems is for stereotactic procedures. At all evaluation sites, the clinical image quality was considered acceptable for the range of examinations undertaken. Two advantages of digital imaging, when compared to film screen imaging, are the speed with which images are displayed and the ability to manipulate and enhance the image. In general, the use of digital imaging has significantly reduced the examination times for stereotactic procedures. However, at a number of evaluation sites, the use of digital imaging has led to an increased number of core biopsies per patient. This is due to the convenience of the systems. Digital acquisition also allows the radiographer to remain in the X-ray room throughout the examination. This was considered a positive benefit and reassuring for the patient. Three of the systems evaluated are provided with automatic control of exposure through the detector system in addition to manual control. One unit has manual control only for which suggested exposure parameters are given in the operator's manual. Typical exposure parameters showed considerable variation from system to system and ranged from levels comparable to up to three times that for film screen imaging. Estimates of mean glandular dose (for typical exposure parameters) were in all cases higher than would expected for film screen methods. Image quality measurements, using a range of test objects, showed that when compared to film screen imaging, low contrast sensitivity was improved although limiting (spatial) resolution was poorer.
    MeSH term(s) Image Processing, Computer-Assisted ; Mammography/instrumentation ; Radiographic Image Enhancement/instrumentation ; Biopsy, Needle/instrumentation ; Biopsy, Needle/methods ; Consumer Behavior ; Costs and Cost Analysis ; Equipment Design/standards ; Equipment Safety/standards ; Radiographic Image Enhancement/methods ; Stereotaxic Techniques/instrumentation ; Humans
    Keywords United Kingdom
    Language English
    Size 26 p. :, ill.
    Publisher Medical Devices Agency
    Publishing place London
    Document type Book
    Note "September 1999."
    Database Catalogue of the US National Library of Medicine (NLM)

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