MRI-based treatment planning for radiotherapy: Dosimetric verification for prostate IMRT

Chen, Lili; Price, Robert A.; Wang, Lu; Li, Jinsheng; Qin, Lianjie; McNeeley, Shawn; Charlie, C.‐M.; Freedman, Gary M.; Pollack, Alan

doi:10.1016/j.ijrobp.2004.05.068

Cited by 132 publications

(81 citation statements)

References 24 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…However, this increased uncertainty in patients with nonstandard internal geometry (21). Another approach is to manually (6,22,23) or automatically (18) segment MR images into one or more material classifications (eg bone, water) and assign bulk CT values to each class. Rank et al (18) performed a variation of this method that, rather than segmenting based on material characteristics, divided the full HU range into a large number of equally spaced regions.…”

Section: Discussionmentioning

confidence: 99%

Implementation of a Novel Algorithm For Generating Synthetic CT Images From Magnetic Resonance Imaging Data Sets for Prostate Cancer Radiation Therapy

Kim

Glide-Hurst

Doemer

et al. 2015

International Journal of Radiation Oncology*Biology*Physics

101

View full text Add to dashboard Cite

Section: Discussionmentioning

confidence: 99%

Implementation of a Novel Algorithm For Generating Synthetic CT Images From Magnetic Resonance Imaging Data Sets for Prostate Cancer Radiation Therapy

Kim

Glide-Hurst

Doemer

et al. 2015

International Journal of Radiation Oncology*Biology*Physics

101

View full text Add to dashboard Cite

“…The prescribed dose (78 Gy) in PTV was defined in both plans as D50 % ∆V75 Gy ∆V70 Gy ∆V50 Gy ∆V30 Gy Rectum % − 0.6 ± 2.6 − 0.9 ± 3.2 − 3.3 ± 3.5 − 4.0 ± 2.6 cm 3 − 0.4 ± 1.9 − 0. 6 bination of the MRI and CT. However, with modern techniques allowing detection and correction of such movement, it may be relevant to reduce the margins to 3-4 mm within the operating limits of the movement tracking systems.…”

Section: Intermodality Differencesmentioning

confidence: 99%

“…The determination of geometrical accuracy has included evaluation of the locations of the body and pelvic bone surfaces, as well as the border between the prostate and rectum, which are sensitive to susceptibility artefacts [2,3]. The radiation dose in the planning target volume (PTV) of the prostate can be calculated with a sufficient accuracy of 1-3 % using MRI images [4][5][6][7][8][9]. CT and MRI image coregistration includes a registration uncertainty, which may decrease the accuracy of clinical target volume (CTV) definition.…”

mentioning

confidence: 99%

Converting from CT- to MRI-only-based target definition in radiotherapy of localized prostate cancer

et al. 2015

View full text Add to dashboard Cite

show abstract

“…feasibility of MR-based dose calculation has been demonstrated for radiotherapy on different treatment regions using manual segmentation and bulk-density assignment [13] [14]. Conversion from MRI to pseudo-CT images has also been reported using anatomy-and voxel-based methods.…”

Section: Introductionmentioning

confidence: 99%

Feasibility of a Direct-Conversion Method from Magnetic Susceptibility to Relative Electron Density for Radiation Therapy Treatment Planning

Ito¹,

Nakajima²,

Saito³

et al. 2017

IJMPCERO

View full text Add to dashboard Cite

Recently, several institutions have been developing magnetic resonance imaging (MRI)-guided radiotherapy treatment systems. In this study, we examine whether it is possible to perform radiation therapy planning (RTP) using a magnetic susceptibility map obtained using MRI. The head of a healthy volunteer was scanned using dual-energy computed tomography (CT) and MRI. A T2-star-weighted 3D gradient echo-based sequence (GRE) with images taken at four different echo times was acquired using the MRI scanner. The CT images were converted to relative electron density (rED) using a predefined ΔCT-rED conversion table. ΔCT was derived using the energy-subtraction method. The rED map was obtained from a single-linear relationship with the ΔCT-rED conversion table, whereas the magnetic susceptibility map was obtained from quantitative susceptibility mapping (QSM) via MRI. Subsequently, to obtain the relationship between the magnetic susceptibility and the rED, the rED map was rigidly aligned to the susceptibility map and resampled at the susceptibility map's resolution. Finally, the magnetic susceptibility rED conversion table was obtained via voxel-by-voxel mapping between the two maps. No strong relationship between magnetic susceptibility and rED was obtained in the healthy volunteer's head or in this study. The coefficient correlation between these parameters was 0.0145. Magnetic susceptibility values may be not able to convert to rED using our proposed method in How to cite this paper: Ito, K., Kadoya, N., Nakajima, Y., Saito, M., Sato, K., Nagasaka, T., Yamanaka, K., Dobashi, S., Takeda healthy volunteer's head. In contrast to the magnetic-susceptibility values obtained from the QSM algorithm, which were strongly affected by calcification and iron content, the rED or CT number was not considerably affected by such materials.

show abstract

MRI-based treatment planning for radiotherapy: Dosimetric verification for prostate IMRT

Cited by 132 publications

References 24 publications

Implementation of a Novel Algorithm For Generating Synthetic CT Images From Magnetic Resonance Imaging Data Sets for Prostate Cancer Radiation Therapy

Implementation of a Novel Algorithm For Generating Synthetic CT Images From Magnetic Resonance Imaging Data Sets for Prostate Cancer Radiation Therapy

Converting from CT- to MRI-only-based target definition in radiotherapy of localized prostate cancer

Feasibility of a Direct-Conversion Method from Magnetic Susceptibility to Relative Electron Density for Radiation Therapy Treatment Planning

Contact Info

Product

Resources

About