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  1. Buch ; Online: Review of radiologic physics

    Huda, Walter

    2010  

    Verfasserangabe Walter Huda
    Schlagwörter Health physics - examination questions
    Sprache Englisch
    Umfang 1 Online-Ressource
    Ausgabenhinweis 3rd ed.
    Verlag Lippincott Williams & Wilkins
    Erscheinungsort Baltimore, MD
    Dokumenttyp Buch ; Online
    Anmerkung Includes bibliographical references and index
    Bemerkung Zugriff für angemeldete ZB MED-Nutzerinnen und -Nutzer
    ISBN 978-0-7817-8569-3 ; 0-7817-8569-3
    Datenquelle ZB MED Katalog Medizin, Gesundheit, Ernährung, Umwelt, Agrar

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  2. Artikel ; Online: Radiation risks: what is to be done?

    Huda, Walter

    AJR. American journal of roentgenology

    2015  Band 204, Heft 1, Seite(n) 124–127

    Abstract: Objective: What is currently known about radiologic risks is reviewed, policies that should be adopted based on our current knowledge are proposed, and how these policies can be applied to adequately protect patients in everyday clinical practice is ... ...

    Abstract Objective: What is currently known about radiologic risks is reviewed, policies that should be adopted based on our current knowledge are proposed, and how these policies can be applied to adequately protect patients in everyday clinical practice is described.
    Conclusion: All activities in life (e.g., driving automobiles) are associated with risks, and medical imaging is no different, so the most important message to convey to patients is whether a proposed examination is worthwhile. Our collective goal should be ensuring that all radiologic examinations are justified and are as low as reasonably achievable (ALARA), which maximizes the benefits of medical imaging for our patients.
    Mesh-Begriff(e) Humans ; Patient Safety/standards ; Patient Safety/statistics & numerical data ; Practice Guidelines as Topic ; Radiation Dosage ; Radiation Injuries/epidemiology ; Radiation Injuries/prevention & control ; Radiation Protection/methods ; Radiation Protection/standards ; Risk Factors ; Tomography, X-Ray Computed/standards ; Tomography, X-Ray Computed/statistics & numerical data
    Sprache Englisch
    Erscheinungsdatum 2015-01
    Erscheinungsland United States
    Dokumenttyp Journal Article ; Review
    ZDB-ID 82076-3
    ISSN 1546-3141 ; 0361-803X ; 0092-5381
    ISSN (online) 1546-3141
    ISSN 0361-803X ; 0092-5381
    DOI 10.2214/AJR.14.12834
    Datenquelle MEDical Literature Analysis and Retrieval System OnLINE

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  3. Artikel ; Online: Kerma-area product in diagnostic radiology.

    Huda, Walter

    AJR. American journal of roentgenology

    2014  Band 203, Heft 6, Seite(n) W565–9

    Mesh-Begriff(e) Absorption, Radiation ; Algorithms ; Computer Simulation ; Models, Biological ; Radiography/methods ; Radiometry/methods ; Tomography, X-Ray Computed ; X-Rays
    Sprache Englisch
    Erscheinungsdatum 2014-12
    Erscheinungsland United States
    Dokumenttyp Journal Article ; Review
    ZDB-ID 82076-3
    ISSN 1546-3141 ; 0361-803X ; 0092-5381
    ISSN (online) 1546-3141
    ISSN 0361-803X ; 0092-5381
    DOI 10.2214/AJR.14.12513
    Datenquelle MEDical Literature Analysis and Retrieval System OnLINE

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  4. Artikel ; Online: Understanding (and explaining) imaging performance metrics.

    Huda, Walter

    AJR. American journal of roentgenology

    2014  Band 203, Heft 1, Seite(n) W1–2

    Mesh-Begriff(e) Diagnostic Imaging/standards ; Humans ; Models, Statistical ; Predictive Value of Tests ; Sensitivity and Specificity
    Sprache Englisch
    Erscheinungsdatum 2014-07
    Erscheinungsland United States
    Dokumenttyp Journal Article
    ZDB-ID 82076-3
    ISSN 1546-3141 ; 0361-803X ; 0092-5381
    ISSN (online) 1546-3141
    ISSN 0361-803X ; 0092-5381
    DOI 10.2214/AJR.13.10827
    Datenquelle MEDical Literature Analysis and Retrieval System OnLINE

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  5. Buch: Review of radiologic physics

    Huda, Walter

    2016  

    Abstract: This book remains focused on imaging using X-rays (i.e., projection radiography, fluoroscopy, and CT), as well as nuclear medicine, ultrasound, and MR"--Provided by publisher. ...

    Verfasserangabe Walter Huda ; illustrations by R. Brad Abrahams
    Abstract "This book remains focused on imaging using X-rays (i.e., projection radiography, fluoroscopy, and CT), as well as nuclear medicine, ultrasound, and MR"--Provided by publisher.
    Mesh-Begriff(e) Health Physics
    Sprache Englisch
    Umfang xv, 315 pages :, illustrations
    Ausgabenhinweis Fourth edition.
    Dokumenttyp Buch
    ISBN 9781496325082 ; 1496325087
    Datenquelle Katalog der US National Library of Medicine (NLM)

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  6. Artikel ; Online: A radiation exposure index for CT.

    Huda, Walter

    Radiation protection dosimetry

    2013  Band 157, Heft 2, Seite(n) 172–180

    Abstract: The purpose of this study is to define an Exposure Index for CT (EI(CT)) and to estimate the magnitude of the EI(CT) for common clinical CT examinations. For a single-axial rotation of a CT X-ray tube that includes only rays that pass through the patient, ...

    Abstract The purpose of this study is to define an Exposure Index for CT (EI(CT)) and to estimate the magnitude of the EI(CT) for common clinical CT examinations. For a single-axial rotation of a CT X-ray tube that includes only rays that pass through the patient, the CT Exposure Index (EI(CT)) is defined as the average Air Kerma that would be incident on an extended 360° detector array completely surrounding the patient. For an axial scan of a uniform cylindrical phantom, EI(CT) can be approximated as T × [(CTDI(air))/4] × [β°/360°] where T is the fractional transmission through the cylinder, CTDI(air) is the CT Dosimetry Index-determined 'free in air' at isocentre, and β/2 is the fan beam angle that will completely irradiate a cylindrical phantom at isocentre. The value of CTDI(air) can be estimated from the weighted CTDI (CTDI(w)) for a given CT examination, and the angle β depends on the irradiation geometry that can be obtained from the cylinder diameter (r) and the focus to isocentre distance (R). At a voltage of 120 kV, transmission through an adult head was ∼2.6%, through an adult abdomen∼0.4% and through a 5-y-old paediatric abdomen ∼3%. Average ratios of CTDI(air)/CTDI(w) were 1.42 ± 0.12 in 16-cm dosimetry phantom and 2.82 ± 0.37 in 32-cm phantom. Values of β ranged from 30.1° (R = 61 cm and r=8 cm) to 85.3° (R = 55 cm and r=20 cm). For an adult head CT examination, EI(CT) was estimated to be∼70 µGy at a CTDI(vol) of 75 mGy (16 cm), and for an adult abdominal CT examination, EI(CT) was estimated to be∼11 µGy at a CTDI(vol) of 25 mGy (32 cm). For an abdomen CT examination in a 5-y-old child, EI(CT) was estimated to be ∼21 µGy at a CTDI(vol) of 20 mGy (16 cm). The EI(CT) is introduced that provides a quantitative measure of the amount of the radiation used to generate images in any CT examination and is analogous to the average image receptor Exposure Index recently proposed for use in projection imaging. The EI(CT) metric provides operators with an objective index of the amount of the radiation used to create CT images and can be used to control quantum mottle in CT.
    Mesh-Begriff(e) Adult ; Algorithms ; Child, Preschool ; Head/diagnostic imaging ; Humans ; Phantoms, Imaging ; Radiation Dosage ; Radiation Protection ; Radiometry/methods ; Tomography, X-Ray Computed
    Sprache Englisch
    Erscheinungsdatum 2013-12
    Erscheinungsland England
    Dokumenttyp Journal Article
    ZDB-ID 225912-6
    ISSN 1742-3406 ; 0144-8420
    ISSN (online) 1742-3406
    ISSN 0144-8420
    DOI 10.1093/rpd/nct128
    Datenquelle MEDical Literature Analysis and Retrieval System OnLINE

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  7. Artikel ; Online: CT dose metrics.

    Huda, Walter

    Radiology

    2013  Band 267, Heft 3, Seite(n) 964–965

    Mesh-Begriff(e) Humans ; Radiation Dosage ; Radiation Injuries/prevention & control ; Radiation Protection/methods ; Terminology as Topic ; Tomography, X-Ray Computed/adverse effects ; Tomography, X-Ray Computed/methods
    Sprache Englisch
    Erscheinungsdatum 2013-06
    Erscheinungsland United States
    Dokumenttyp Comment ; Letter
    ZDB-ID 80324-8
    ISSN 1527-1315 ; 0033-8419
    ISSN (online) 1527-1315
    ISSN 0033-8419
    DOI 10.1148/radiol.13122469
    Datenquelle MEDical Literature Analysis and Retrieval System OnLINE

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  8. Buch: Review of radiologic physics

    Huda, Walter / Slone, Richard M.

    1995  

    Verfasserangabe Walter Huda ; Richard M. Slone
    Schlagwörter Health Physics / examination questions
    Sprache Englisch
    Umfang XV, 286 S. : Ill., graph. Darst.
    Verlag Williams & Wilkins
    Erscheinungsort Baltimore u.a.
    Erscheinungsland Vereinigte Staaten
    Dokumenttyp Buch
    HBZ-ID HT006736587
    ISBN 0-683-04230-0 ; 978-0-683-04230-6
    Datenquelle Katalog ZB MED Medizin, Gesundheit

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  9. Artikel ; Online: What ER radiologists need to know about radiation risks.

    Huda, Walter

    Emergency radiology

    2009  Band 16, Heft 5, Seite(n) 335–341

    Abstract: The annual per capita medical dose in the US is currently 3 mSv, and has increased by about 600% since the early 1980s. Medical doses now account for approximately 50% of the total US population dose, and will likely continue to increase for the ... ...

    Abstract The annual per capita medical dose in the US is currently 3 mSv, and has increased by about 600% since the early 1980s. Medical doses now account for approximately 50% of the total US population dose, and will likely continue to increase for the foreseeable future. An average patient at a Level 1 trauma center, with an Injury Severity Score of 14, is expected to undergo imaging procedures that will result in an effective dose of approximately 40 mSv. The median age of a trauma patient in the ER setting is about 30 years, and the male cancer incidence from this amount of radiation is estimated to be approximately 0.3%, with the female risk being approximately 55% higher. For radiation protection purposes, scientific radiation protection authorities consider that the available evidence shows the linear no threshold (LNT) model to be the most prudent one for radiation protection purposes. Accepting that diagnostic examinations are associated with finite radiation risks requires policies that protect patients from unnecessary radiation. Clinical practice should therefore ensure that: (a) tests should only be ordered when the results are expected to affect patient management; (b) non-ionizing alternatives (i.e., US and MR) be considered, particularly for pediatric patients; (c) only indicated exams should be performed where the patient benefit is judged to exceed any radiation risk; and (d) for indicated examinations, all radiation exposures are kept As Low As Reasonably Achievable (ALARA).
    Mesh-Begriff(e) Adult ; Emergency Medicine ; Female ; Humans ; Male ; Radiation Monitoring ; Risk
    Sprache Englisch
    Erscheinungsdatum 2009-02-27
    Erscheinungsland United States
    Dokumenttyp Journal Article
    ZDB-ID 1425144-9
    ISSN 1438-1435 ; 1070-3004
    ISSN (online) 1438-1435
    ISSN 1070-3004
    DOI 10.1007/s10140-009-0801-2
    Datenquelle MEDical Literature Analysis and Retrieval System OnLINE

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  10. Artikel ; Online: Doses metrics and patient age in CT.

    Huda, Walter / Tipnis, Sameer V

    Radiation protection dosimetry

    2016  Band 168, Heft 3, Seite(n) 374–380

    Abstract: The aim of this study was to investigate how effective dose and size-specific dose estimate (SSDE) change with patient age (size) for routine head and abdominal/pelvic CT examinations. Heads and abdomens of patients were modelled as a mass-equivalent ... ...

    Abstract The aim of this study was to investigate how effective dose and size-specific dose estimate (SSDE) change with patient age (size) for routine head and abdominal/pelvic CT examinations. Heads and abdomens of patients were modelled as a mass-equivalent cylinder of water corresponding to the patient 'effective diameter'. Head CT scans were performed at CTDIvol(S) of 40 mGy, and abdominal CT scans were performed at CTDIvol(L) of 10 mGy. Values of SSDE were obtained using conversion factors in AAPM Task Group Report 204. Age-specific scan lengths for head and abdominal CT scans obtained from the authors' clinical practice were used to estimate the dose-length product for each CT examination. Effective doses were calculated from previously published age- and sex-specific E/DLP conversion factors, based on ICRP 103 organ-weighting factors. For head CT examinations, the scan length increased from 15 cm in a newborn to 20 cm in adults, and for an abdominal/pelvic CT, the scan length increased from 20 cm in a newborn to 45 cm in adults. For head CT scans, SSDE ranged from 37.2 mGy in adults to 48.8 mGy in a newborn, an increase of 31 %. The corresponding head CT effective doses range from 1.4 mSv in adults to 5.2 mSv in a newborn, an increase of 270 %. For abdomen CT scans, SSDE ranged from 13.7 mGy in adults to 23.0 mGy in a newborn, an increase of 68 %. The corresponding abdominal CT effective doses ranged from 6.3 mSv in adults to 15.4 mSv in a newborn, an increase of 140 %. SSDE increases much less than effective dose in paediatric patients compared with adults because it does not account for scan length or scattered radiation. Size- and age-specific effective doses better quantify the total radiation received by patients in CT by explicitly accounting for all organ doses, as well as their relative radio sensitivity.
    Mesh-Begriff(e) Adolescent ; Adult ; Female ; Head/diagnostic imaging ; Humans ; Infant, Newborn ; Male ; Pelvis/diagnostic imaging ; Radiation Dosage ; Tomography, X-Ray Computed/methods ; Young Adult
    Sprache Englisch
    Erscheinungsdatum 2016-03
    Erscheinungsland England
    Dokumenttyp Comparative Study ; Journal Article
    ZDB-ID 225912-6
    ISSN 1742-3406 ; 0144-8420
    ISSN (online) 1742-3406
    ISSN 0144-8420
    DOI 10.1093/rpd/ncv310
    Datenquelle MEDical Literature Analysis and Retrieval System OnLINE

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