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Title: Calibration setting numbers for dose calibrators for the PET isotopes 52 Mn, 64 Cu, 76 Br, 86 Y, 89 Zr, 124 I

Authors:
; ; ; ; ; ; ;
Publication Date:
Sponsoring Org.:
USDOE
OSTI Identifier:
1358795
Grant/Contract Number:
NA0000979
Resource Type:
Journal Article: Publisher's Accepted Manuscript
Journal Name:
Applied Radiation and Isotopes
Additional Journal Information:
Journal Volume: 113; Journal Issue: C; Related Information: CHORUS Timestamp: 2017-10-03 22:15:44; Journal ID: ISSN 0969-8043
Publisher:
Elsevier
Country of Publication:
United Kingdom
Language:
English

Citation Formats

Wooten, A. Lake, Lewis, Benjamin C., Szatkowski, Daniel J., Sultan, Deborah H., Abdin, Kinda I., Voller, Thomas F., Liu, Yongjian, and Lapi, Suzanne E. Calibration setting numbers for dose calibrators for the PET isotopes 52 Mn, 64 Cu, 76 Br, 86 Y, 89 Zr, 124 I. United Kingdom: N. p., 2016. Web. doi:10.1016/j.apradiso.2016.04.025.
Wooten, A. Lake, Lewis, Benjamin C., Szatkowski, Daniel J., Sultan, Deborah H., Abdin, Kinda I., Voller, Thomas F., Liu, Yongjian, & Lapi, Suzanne E. Calibration setting numbers for dose calibrators for the PET isotopes 52 Mn, 64 Cu, 76 Br, 86 Y, 89 Zr, 124 I. United Kingdom. doi:10.1016/j.apradiso.2016.04.025.
Wooten, A. Lake, Lewis, Benjamin C., Szatkowski, Daniel J., Sultan, Deborah H., Abdin, Kinda I., Voller, Thomas F., Liu, Yongjian, and Lapi, Suzanne E. 2016. "Calibration setting numbers for dose calibrators for the PET isotopes 52 Mn, 64 Cu, 76 Br, 86 Y, 89 Zr, 124 I". United Kingdom. doi:10.1016/j.apradiso.2016.04.025.
@article{osti_1358795,
title = {Calibration setting numbers for dose calibrators for the PET isotopes 52 Mn, 64 Cu, 76 Br, 86 Y, 89 Zr, 124 I},
author = {Wooten, A. Lake and Lewis, Benjamin C. and Szatkowski, Daniel J. and Sultan, Deborah H. and Abdin, Kinda I. and Voller, Thomas F. and Liu, Yongjian and Lapi, Suzanne E.},
abstractNote = {},
doi = {10.1016/j.apradiso.2016.04.025},
journal = {Applied Radiation and Isotopes},
number = C,
volume = 113,
place = {United Kingdom},
year = 2016,
month = 7
}

Journal Article:
Free Publicly Available Full Text
Publisher's Version of Record at 10.1016/j.apradiso.2016.04.025

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  • Purpose: In nuclear medicine, the activity of a radionuclide is measured with a radionuclide calibrator that often has a calibration coefficient independent of the container type and filling. Methods: To determine the effect of the container on the accuracy of measuring the activity injected into a patient, The authors simulated a commercial radionuclide calibrator and 18 container types most typically used in clinical practice. The instrument sensitivity was computed for various container thicknesses and filling levels. Monoenergetic photons and electrons as well as seven common radionuclides were considered. Results: The quality of the simulation with gamma-emitting sources was validated bymore » an agreement with measurements better than 4% in five selected radionuclides. The results show that the measured activity can vary by more than a factor of 2 depending on the type of container. The filling level and the thickness of the container wall only have a marginal effect for radionuclides of high energy but could induce differences up to 4%. Conclusions: The authors conclude that radionuclide calibrators should be tailored to the uncertainty required by clinical applications. For most clinical cases, and at least for the low-energy gamma and x-ray emitters, measurements should be performed with calibration coefficients specific to the container type.« less
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  • Megavoltage cone-beam CT (MV CBCT) is used for three-dimensional imaging of the patient anatomy on the treatment table prior to or just after radiotherapy treatment. To use MV CBCT images for radiotherapy dose calculation purposes, reliable electron density (ED) distributions are needed. Patient scatter, beam hardening and softening effects result in cupping artifacts in MV CBCT images and distort the CT number to ED conversion. A method based on transmission images is presented to correct for these effects without using prior knowledge of the object's geometry. The scatter distribution originating from the patient is calculated with pencil beam scatter kernelsmore » that are fitted based on transmission measurements. The radiological thickness is extracted from the scatter subtracted transmission images and is then converted to the primary transmission used in the cone-beam reconstruction. These corrections are performed in an iterative manner, without using prior knowledge regarding the geometry and composition of the object. The method was tested using various homogeneous and inhomogeneous phantoms with varying shapes and compositions, including a phantom with different electron density inserts, phantoms with large density variations, and an anthropomorphic head phantom. For all phantoms, the cupping artifact was substantially removed from the images and a linear relation between the CT number and electron density was found. After correction the deviations in reconstructed ED from the true values were reduced from up to 0.30 ED units to 0.03 for the majority of the phantoms; the residual difference is equal to the amount of noise in the images. The ED distributions were evaluated in terms of absolute dose calculation accuracy for homogeneous cylinders of different size; errors decreased from 7% to below 1% in the center of the objects for the uncorrected and corrected images, respectively, and maximum differences were reduced from 17% to 2%, respectively. The presented method corrects the MV CBCT images for cupping artifacts and extracts reliable ED information of objects with varying geometries and composition, making these corrected MV CBCT images suitable for accurate dose calculation purposes.« less
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