Abstract：
:To estimate the lung tumor position from multiple anatomical features on four-dimensional computed tomography (4D-CT) data sets using single regression analysis (SRA) and multiple regression analysis (MRA) approach and evaluate an impact of the approach on internal target volume (ITV) for stereotactic body radiotherapy (SBRT) of the lung. Eleven consecutive lung cancer patients (12 cases) underwent 4D-CT scanning. The three-dimensional (3D) lung tumor motion exceeded 5 mm. The 3D tumor position and anatomical features, including lung volume, diaphragm, abdominal wall, and chest wall positions, were measured on 4D-CT images. The tumor position was estimated by SRA using each anatomical feature and MRA using all anatomical features. The difference between the actual and estimated tumor positions was defined as the root-mean-square error (RMSE). A standard partial regression coefficient for the MRA was evaluated. The 3D lung tumor position showed a high correlation with the lung volume (R = 0.92 ± 0.10). Additionally, ITVs derived from SRA and MRA approaches were compared with ITV derived from contouring gross tumor volumes on all 10 phases of the 4D-CT (conventional ITV). The RMSE of the SRA was within 3.7 mm in all directions. Also, the RMSE of the MRA was within 1.6 mm in all directions. The standard partial regression coefficient for the lung volume was the largest and had the most influence on the estimated tumor position. Compared with conventional ITV, average percentage decrease of ITV were 31.9% and 38.3% using SRA and MRA approaches, respectively. The estimation accuracy of lung tumor position was improved by the MRA approach, which provided smaller ITV than conventional ITV.
journal_name
J Appl Clin Med Physjournal_title
Journal of applied clinical medical physicsauthors
Ono T,Nakamura M,Hirose Y,Kitsuda K,Ono Y,Ishigaki T,Hiraoka Mdoi
10.1002/acm2.12121subject
Has Abstractpub_date
2017-09-01 00:00:00pages
36-42issue
5issn
1526-9914journal_volume
18pub_type
杂志文章abstract：:An inverse treatment planning (ITP) module on a commercial treatment planning system (TPS) (Helax AB, Uppsala, Sweden) is being used for an in-house clinical trial for treatment of nasopharyngeal cancer with contralateral parotid sparing. Intensity modulated radiation therapy (IMRT) fields are delivered by step and sh...
journal_title：Journal of applied clinical medical physics
pub_type： 杂志文章
doi：10.1120/jacmp.v3i2.2580
更新日期：2002-04-01 00:00:00
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journal_title：Journal of applied clinical medical physics
pub_type： 杂志文章
doi：10.1120/jacmp.v14i3.4203
更新日期：2013-05-06 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：2009-12-03 00:00:00
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journal_title：Journal of applied clinical medical physics
pub_type： 杂志文章
doi：10.1120/jacmp.v17i3.5900
更新日期：2016-05-08 00:00:00
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journal_title：Journal of applied clinical medical physics
pub_type： 杂志文章
doi：10.1002/acm2.12854
更新日期：2020-05-01 00:00:00
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journal_title：Journal of applied clinical medical physics
pub_type： 杂志文章
doi：10.1120/jacmp.v14i2.4111
更新日期：2013-03-04 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：2015-05-08 00:00:00
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journal_title：Journal of applied clinical medical physics
pub_type： 杂志文章
doi：10.1120/jacmp.v16i3.5200
更新日期：2015-05-08 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：2011-11-15 00:00:00
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journal_title：Journal of applied clinical medical physics
pub_type： 杂志文章
doi：10.1120/jacmp.v15i1.4445
更新日期：2014-01-06 00:00:00
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journal_title：Journal of applied clinical medical physics
pub_type： 杂志文章
doi：10.1120/jacmp.v17i1.5876
更新日期：2016-01-08 00:00:00
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journal_title：Journal of applied clinical medical physics
pub_type： 杂志文章
doi：10.1120/jacmp.v2i3.2607
更新日期：2001-07-01 00:00:00
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journal_title：Journal of applied clinical medical physics
pub_type： 杂志文章
doi：10.1002/acm2.13057
更新日期：2020-11-03 00:00:00
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journal_title：Journal of applied clinical medical physics
pub_type： 杂志文章
doi：10.1120/jacmp.v10i3.2979
更新日期：2009-06-02 00:00:00
abstract：:Continuous arterial spin labeling (CASL) is a technique for performing quantitative perfusion measurements without the need for exogenous contrast agent administration. This technique has seen limited use in the clinic due to problems of poor sensitivity and the potential for artifacts. In addition, CASL requires the ...
journal_title：Journal of applied clinical medical physics
pub_type： 临床试验,杂志文章
doi：10.1120/jacmp.v6i1.2068
更新日期：2005-01-01 00:00:00
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journal_title：Journal of applied clinical medical physics
pub_type： 杂志文章
doi：10.1002/acm2.12861
更新日期：2020-05-01 00:00:00
abstract：:Relative dose measurements with small ionization chambers in combination with an electrometer placed in the treatment room ("internal electrometer") show a large dependence on the polarity used. While this was observed previously for percent depth dose curves (PDDs), the effect has not been understood or preventable. ...
journal_title：Journal of applied clinical medical physics
pub_type： 杂志文章
doi：10.1002/acm2.12458
更新日期：2018-11-01 00:00:00
abstract：:Intra-fraction organ motion during the dynamic delivery of IMRT treatment of lung tumors may cause unexpected hot/cold spots even within the target volume, due to the interplay effect between tumor motion and multi-leaf collimator (MLC) leaf motion. In the past, this has been investigated through theoretical analysis,...
journal_title：Journal of applied clinical medical physics
pub_type： 杂志文章
doi：10.1120/jacmp.v7i4.2222
更新日期：2006-11-28 00:00:00
abstract：:The objective of this work is the investigation of intense pulsed light (IPL) photoepilation using Monte Carlo simulation to model the effect of the output dosimetry with millisecond exposure used by typical commercial IPL systems. The temporal pulse shape is an important parameter, which may affect the biological tis...
journal_title：Journal of applied clinical medical physics
pub_type： 杂志文章
doi：10.1120/jacmp.v13i5.3702
更新日期：2012-09-06 00:00:00
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journal_title：Journal of applied clinical medical physics
pub_type： 杂志文章
doi：10.1002/acm2.12560
更新日期：2019-06-01 00:00:00
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pub_type： 杂志文章
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更新日期：2008-04-16 00:00:00
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journal_title：Journal of applied clinical medical physics
pub_type： 杂志文章
doi：10.1002/acm2.12227
更新日期：2018-01-01 00:00:00
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journal_title：Journal of applied clinical medical physics
pub_type： 杂志文章
doi：10.1120/jacmp.v16i3.5283
更新日期：2015-05-08 00:00:00
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journal_title：Journal of applied clinical medical physics
pub_type： 杂志文章
doi：10.1120/jacmp.v10i1.2905
更新日期：2009-01-27 00:00:00
abstract：:A custom-made computer program, SWIMRT, to construct "multileaf collimator (MLC) machine" file for intensity-modulated radiotherapy (IMRT) fluence maps was developed using MATLAB and the sliding window algorithm. The user can either import a fluence map with a graphical file format created by an external treatment-pla...
journal_title：Journal of applied clinical medical physics
pub_type： 杂志文章
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更新日期：2006-05-25 00:00:00
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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： 杂志文章
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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：2019-12-01 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
doi：10.1002/acm2.12709
更新日期：2019-10-01 00:00:00
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journal_title：Journal of applied clinical medical physics
pub_type： 杂志文章
doi：10.1120/jacmp.v17i5.6294
更新日期：2016-09-08 00:00:00
