Abstract:
:Radiation dose in computed tomography (CT) has become a hot topic due to an upward trend in the number of CT procedures worldwide and the relatively high doses associated with these procedures. The main aim of this review article is to provide an overview of the most frequently used metrics for CT radiation dose characterization, discuss their strengths and limitations, and present patient dose assessment methods. Computed tomography dosimetry is still based on a CT dose index (CTDI) measured using 100-mm-long pencil ionization chambers and standard dosimetry phantoms (CTDI100). This dose index is easily measured but has important limitations. Computed tomography dose index underestimates the dose generated by modern CT scanners with wide beam collimation. Manufacturers should report corrected CTDI values in the consoles of CT systems. The size-specific dose estimate has been proposed to provide an estimate of the average dose at the center of the scan volume along the z-axis of a CT scan. Size-specific dose estimate is based on CTDI and conversion factors and, therefore, its calculation incorporates uncertainties associated with the measurement of CTDI. Moreover, the calculation of size-specific dose estimate is straightforward only when the tube current modulation is not activated and when the patient body diameter does not change considerably along the z-axis of the scan. Effective dose can be used to provide typical patient dose values from CT examinations, compare dose between modalities, and communicate radiogenic risks. In practice, effective dose has been used incorrectly, for example, to characterize a CT procedure as a low-dose examination. Organ or tissue doses, not effective doses, are required for assessing the probability of cancer induction in exposed individuals. Monte Carlo simulation is a powerful technique to estimate organ and tissue dose from CT. However, vendors should make available to the research community the required information to model the imaging process of their CT scanners. Personalized dosimetry based on Monte Carlo simulation and patient models allows accurate organ dose estimation. However, it is not user friendly and fast enough to be applied routinely. Future research efforts should involve the development of advanced artificial intelligence algorithms to overcome drawbacks associated with the current equipment-specific and patient-specific dosimetry.
journal_name
Invest Radioljournal_title
Investigative radiologyauthors
Damilakis Jdoi
10.1097/RLI.0000000000000727subject
Has Abstractpub_date
2021-01-01 00:00:00pages
62-68issue
1eissn
0020-9996issn
1536-0210journal_volume
56pub_type
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journal_title:Investigative radiology
pub_type: 杂志文章
doi:10.1097/00004424-198809001-00006
更新日期:1988-09-01 00:00:00
abstract:OBJECTIVE:The objective of this study was to validate quantitation of R2* and DeltaR2* measurements obtained with a 3-dimensional (3-D) multiple gradient-recalled echo (mGRE) sequence for evaluating intrarenal oxygenation in humans. MATERIALS AND METHODS:Validation was accomplished (1) by comparing R2* values with pre...
journal_title:Investigative radiology
pub_type: 杂志文章
doi:10.1097/01.rli.0000187166.43871.fb
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journal_title:Investigative radiology
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doi:10.1097/RLI.0b013e318181538a
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doi:10.1097/RLI.0b013e318262292e
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abstract:RATIONALE AND OBJECTIVES:This study assesses the ability of a cardiac-gated phase-contrast magnetic resonance imaging (MRI) technique to measure renal blood flow (RBF) noninvasively in humans. METHODS:In nine normal volunteers, total RBF in the renal arteries and in the left renal vein was estimated by MRI and correla...
journal_title:Investigative radiology
pub_type: 杂志文章
doi:10.1097/00004424-199206000-00012
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journal_title:Investigative radiology
pub_type: 杂志文章
doi:10.1097/00004424-199212000-00011
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journal_title:Investigative radiology
pub_type: 杂志文章
doi:10.1097/00004424-200012000-00007
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pub_type: 杂志文章
doi:10.1097/01.rli.0000183054.43131.a8
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journal_title:Investigative radiology
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doi:10.1097/RLI.0b013e3181d2eeb1
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journal_title:Investigative radiology
pub_type: 杂志文章
doi:10.1097/00004424-200108000-00008
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journal_title:Investigative radiology
pub_type: 杂志文章
doi:10.1097/00004424-199701000-00011
更新日期:1997-01-01 00:00:00
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journal_title:Investigative radiology
pub_type: 杂志文章
doi:10.1097/RLI.0b013e31817e9b52
更新日期:2008-08-01 00:00:00
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journal_title:Investigative radiology
pub_type: 杂志文章
doi:10.1097/00004424-198908000-00007
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journal_title:Investigative radiology
pub_type: 杂志文章
doi:10.1097/RLI.0b013e31823076a4
更新日期:2012-02-01 00:00:00
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journal_title:Investigative radiology
pub_type: 杂志文章
doi:10.1097/00004424-199007000-00016
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journal_title:Investigative radiology
pub_type: 杂志文章
doi:10.1097/00004424-198805000-00005
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journal_title:Investigative radiology
pub_type: 杂志文章
doi:10.1097/00004424-199201000-00008
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journal_title:Investigative radiology
pub_type: 杂志文章
doi:10.1097/RLI.0000000000000638
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journal_title:Investigative radiology
pub_type: 杂志文章
doi:10.1097/00004424-198105000-00004
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journal_title:Investigative radiology
pub_type: 杂志文章
doi:10.1097/RLI.0b013e31821e62fb
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journal_title:Investigative radiology
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doi:10.1097/RLI.0000000000000582
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journal_title:Investigative radiology
pub_type: 杂志文章
doi:10.1097/00004424-198602000-00014
更新日期:1986-02-01 00:00:00
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journal_title:Investigative radiology
pub_type: 杂志文章
doi:10.1097/00004424-199711000-00010
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journal_title:Investigative radiology
pub_type: 杂志文章
doi:10.1097/00004424-199605000-00010
更新日期:1996-05-01 00:00:00
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journal_title:Investigative radiology
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doi:10.1097/RLI.0b013e3181994a73
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journal_title:Investigative radiology
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journal_title:Investigative radiology
pub_type: 杂志文章
doi:10.1097/01.rli.0000155285.05672.cf
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journal_title:Investigative radiology
pub_type: 杂志文章
doi:10.1097/RLI.0000000000000696
更新日期:2020-09-01 00:00:00