Abstract:
PURPOSE:The purpose of this study was to optimize intra-voxel incoherent motion (IVIM) measurement in diffusion-weighted imaging (DWI) of breast cancer by separating perfusion and diffusion effects through the determination of an optimal threshold b-value, thus benign and cancerous breast tissues can be accurately differentiated using IVIM-derived diffusion and perfusion parameters. MATERIALS AND METHODS:Twenty-eight patients, with biopsy-confirmed breast cancers, were studied with a 3T MRI scanner, using T1-weighted dynamic contrast-enhanced MRI images, and diffusion-weighted images with nine b-values, ranging from 0 to 1000 s/mm². IVIM-derived parameter maps for tissue diffusion coefficients D, perfusion fraction f, and pseudo-diffusion coefficients D* were computed using the segmented fitting method with optimized threshold b-value, and the sum of squared residuals (SSR) were calculated for IVIM-derived parameters in different breast lesions. RESULTS:The IVIM analysis method developed in this work can separate perfusion and diffusion effects with the optimal threshold b-value of 300 s/mm², and the results of diffusion and perfusion parameters from IVIM analysis can be used to differentiate pathological changes in breast tissues. It was found that the averages and standard deviations of the diffusion and perfusion parameters, D, f, D*, are the following, for malignant, benign and normal breast tissues respectively: D (0.813 ± 0.225 × 10-3 mm2 /s, 1.437 ± 0.538 × 10-3 mm2 /s, 1.838 ± 0.213 × 10-3 mm2 /s), f (10.73 ± 3.44%, 7.86 ± 3.70%, 8.92 ± 3.72%), D* (15.23 ± 12.17×10-3 mm²/s, 12.02 ± 3.19 × 10-3 mm2 /s, 12.03 ± 7.21 × 10-3 mm2 /s). CONCLUSION:IVIM-derived diffusion and perfusion parameter maps depend highly on the choice of threshold b-value. Using the methodology developed in this work, and with the optimized threshold b-value, the diffusion and perfusion parameters of breast tissues can be accurately assessed, making IVIM MRI a technique of choice for differential diagnosis of breast cancer.
journal_name
J Appl Clin Med Physjournal_title
Journal of applied clinical medical physicsauthors
Chen W,Zhang J,Long D,Wang Z,Zhu JMdoi
10.1002/acm2.12065subject
Has Abstractpub_date
2017-05-01 00:00:00pages
191-199issue
3issn
1526-9914journal_volume
18pub_type
杂志文章abstract::Stereotactic body radiation therapy (SBRT) has been increasingly used as an efficacious treatment modality for early-stage non-small cell lung cancer. The accuracy of dose calculations is compromised due to the presence of inhomogeneity. For the purpose of a consistent prescription, radiation doses were calculated wit...
journal_title:Journal of applied clinical medical physics
pub_type: 杂志文章
doi:10.1120/jacmp.v14i2.4011
更新日期:2013-03-04 00:00:00
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journal_title:Journal of applied clinical medical physics
pub_type: 临床试验,杂志文章
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abstract::The control loop in the Varian DMLC system (V4.8) requires approximately 65 msec to monitor and halt the irradiation of a segment, causing an "overshoot" effect: the segment ends on a fractional monitor unit larger than that planned. As a result, the actual MU delivered may differ from that planned. In general, for st...
journal_title:Journal of applied clinical medical physics
pub_type: 杂志文章
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journal_title:Journal of applied clinical medical physics
pub_type: 杂志文章
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journal_title:Journal of applied clinical medical physics
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abstract::Flattening filter-free (FFF) beams are becoming the preferred beam type for stereotactic radiosurgery (SRS) and stereotactic ablative radiation therapy (SABR), as they enable an increase in dose rate and a decrease in treatment time. This work assesses the effects of the flattening filter on small field output factors...
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journal_title:Journal of applied clinical medical physics
pub_type: 杂志文章
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更新日期:2018-11-01 00:00:00
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journal_title:Journal of applied clinical medical physics
pub_type: 杂志文章
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更新日期:2008-04-16 00:00:00
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更新日期:2010-01-28 00:00:00
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journal_title:Journal of applied clinical medical physics
pub_type: 杂志文章
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更新日期:2012-01-05 00:00:00
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journal_title:Journal of applied clinical medical physics
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更新日期:2006-01-01 00:00:00
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更新日期:2015-01-08 00:00:00
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journal_title:Journal of applied clinical medical physics
pub_type: 杂志文章
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更新日期:2002-07-01 00:00:00
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journal_title:Journal of applied clinical medical physics
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更新日期:2016-09-08 00:00:00
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journal_title:Journal of applied clinical medical physics
pub_type: 杂志文章
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更新日期:2017-01-01 00:00:00
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journal_title:Journal of applied clinical medical physics
pub_type: 杂志文章
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更新日期:2020-01-01 00:00:00
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journal_title:Journal of applied clinical medical physics
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更新日期:2012-05-10 00:00:00
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journal_title:Journal of applied clinical medical physics
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journal_title:Journal of applied clinical medical physics
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journal_title:Journal of applied clinical medical physics
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journal_title:Journal of applied clinical medical physics
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journal_title:Journal of applied clinical medical physics
pub_type: 杂志文章
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更新日期:2018-07-01 00:00:00
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journal_title:Journal of applied clinical medical physics
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更新日期:2013-09-06 00:00:00
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journal_title:Journal of applied clinical medical physics
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更新日期:2020-10-23 00:00:00
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journal_title:Journal of applied clinical medical physics
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更新日期:2015-11-08 00:00:00
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journal_title:Journal of applied clinical medical physics
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