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  1. Article ; Online: Conebeam CT of the head and neck, part 1: physical principles.

    Miracle, A C / Mukherji, S K

    AJNR. American journal of neuroradiology

    2009  Volume 30, Issue 6, Page(s) 1088–1095

    Abstract: ... high-spatial-resolution visualization of high-contrast structures in the head and neck and ... CBCT imaging as it is used in dedicated head and neck scanners. Concepts related to CBCT acquisition ... other anatomic areas. This first installment in a 2-part review will address the physical principles underlying ...

    Abstract Conebeam x-ray CT (CBCT) is a developing imaging technique designed to provide relatively low-dose high-spatial-resolution visualization of high-contrast structures in the head and neck and other anatomic areas. This first installment in a 2-part review will address the physical principles underlying CBCT imaging as it is used in dedicated head and neck scanners. Concepts related to CBCT acquisition geometry, flat panel detection, and image quality will be explored in detail. Particular emphasis will be placed on technical limitations to low-contrast detectability and radiation dose. Proposed methods of x-ray scatter reduction will also be discussed.
    MeSH term(s) Algorithms ; Cone-Beam Computed Tomography/methods ; Head/diagnostic imaging ; Head and Neck Neoplasms/diagnostic imaging ; Humans ; Imaging, Three-Dimensional/methods ; Neck/diagnostic imaging ; Pattern Recognition, Automated/methods ; Radiographic Image Enhancement/methods ; Radiographic Image Interpretation, Computer-Assisted/methods
    Language English
    Publishing date 2009-05-13
    Publishing country United States
    Document type Journal Article ; Review
    ZDB-ID 603808-6
    ISSN 1936-959X ; 0195-6108
    ISSN (online) 1936-959X
    ISSN 0195-6108
    DOI 10.3174/ajnr.A1653
    Database MEDical Literature Analysis and Retrieval System OnLINE

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    In stock of ZB MED Cologne/Königswinter

    Zs.A 1580: Show issues Location:
    Je nach Verfügbarkeit (siehe Angabe bei Bestand)
    bis Jg. 1994: Bestellungen von Artikeln über das Online-Bestellformular
    Jg. 1995 - 2021: Lesesall (1.OG)
    ab Jg. 2022: Lesesaal (EG)

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  2. Article ; Online: Reconstructing cone-beam CT with spatially varying qualities for adaptive radiotherapy: a proof-of-principle study.

    Lu, Wenting / Yan, Hao / Gu, Xuejun / Tian, Zhen / Luo, Ouyang / Yang, Liu / Zhou, Linghong / Cervino, Laura / Wang, Jing / Jiang, Steve / Jia, Xun

    Physics in medicine and biology

    2014  Volume 59, Issue 20, Page(s) 6251–6266

    Abstract: ... based on these projection data. We have validated our method on a simulated head-and-neck (HN) patient ... radiation therapy (ART), we propose in this paper a new cone beam CT (CBCT) acquisition and reconstruction method ... for the entire image and ~1% within the ROI compared to the ground truth have been observed. These numbers ...

    Abstract With the aim of maximally reducing imaging dose while meeting requirements for adaptive radiation therapy (ART), we propose in this paper a new cone beam CT (CBCT) acquisition and reconstruction method that delivers images with a low noise level inside a region of interest (ROI) and a relatively high noise level outside the ROI. The acquired projection images include two groups: densely sampled projections at a low exposure with a large field of view (FOV) and sparsely sampled projections at a high exposure with a small FOV corresponding to the ROI. A new algorithm combining the conventional filtered back-projection algorithm and the tight-frame iterative reconstruction algorithm is also designed to reconstruct the CBCT based on these projection data. We have validated our method on a simulated head-and-neck (HN) patient case, a semi-real experiment conducted on a HN cancer patient under a full-fan scan mode, as well as a Catphan phantom under a half-fan scan mode. Relative root-mean-square errors (RRMSEs) of less than 3% for the entire image and ~1% within the ROI compared to the ground truth have been observed. These numbers demonstrate the ability of our proposed method to reconstruct high-quality images inside the ROI. As for the part outside ROI, although the images are relatively noisy, it can still provide sufficient information for radiation dose calculations in ART. Dose distributions calculated on our CBCT image and on a standard CBCT image are in agreement, with a mean relative difference of 0.082% inside the ROI and 0.038% outside the ROI. Compared with the standard clinical CBCT scheme, an imaging dose reduction of approximately 3-6 times inside the ROI was achieved, as well as an 8 times outside the ROI. Regarding computational efficiency, it takes 1-3 min to reconstruct a CBCT image depending on the number of projections used. These results indicate that the proposed method has the potential for application in ART.
    MeSH term(s) Algorithms ; Cone-Beam Computed Tomography/methods ; Head and Neck Neoplasms/diagnostic imaging ; Head and Neck Neoplasms/radiotherapy ; Humans ; Image Processing, Computer-Assisted/methods ; Phantoms, Imaging ; Radiotherapy Planning, Computer-Assisted/methods
    Language English
    Publishing date 2014-09-26
    Publishing country England
    Document type Journal Article ; Research Support, N.I.H., Extramural ; Research Support, Non-U.S. Gov't ; Validation Study
    ZDB-ID 208857-5
    ISSN 1361-6560 ; 0031-9155
    ISSN (online) 1361-6560
    ISSN 0031-9155
    DOI 10.1088/0031-9155/59/20/6251
    Database MEDical Literature Analysis and Retrieval System OnLINE

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    In stock of ZB MED Cologne/Königswinter

    Zs.A 199: Show issues Location:
    Je nach Verfügbarkeit (siehe Angabe bei Bestand)
    bis Jg. 1994: Bestellungen von Artikeln über das Online-Bestellformular
    Jg. 1995 - 2021: Lesesall (1.OG)
    ab Jg. 2022: Lesesaal (EG)

    Order via subito

    This service is chargeable due to the Delivery terms set by subito. Orders including an article and supplementary material will be classified as separate orders. In these cases, fees will be demanded for each order.

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